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SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1227 PM CDT Sun Jul 28 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN PLAINS... ...SUMMARY... Scattered strong to severe storms are possible in portions of the Midwest and the northern Plains on Monday. ...Synopsis... Upper ridging is expected to become established from the southern Plains into the Gulf of Mexico on Monday, with modest upper troughing across the Pacific Northwest and an upper low off the coast of southern New England. Some enhanced westerly/northwesterly flow aloft is anticipated between the Pacific Northwest trough and the New England cyclone, extending from the northern Great Basin into the Upper/Mid MS Valley. A pair of shortwave troughs will likely be embedded within this stronger flow, a convectively augmented shortwave expected to begin the period over the Mid MS Valley and a low-amplitude wave expected to develop during the afternoon over the northern High Plains. The convectively augmented shortwave is forecast to continue southeastward across the middle OH Valley throughout the day while the developing wave continues eastward across the northern Plains. A complex surface pattern will likely be in place early Monday, with several areas of low pressure expected to be embedded within a broad area of troughing extending from the Upper Midwest through the central Plains. A moist airmass will exist east of the modest surface trough extending between these lows. ...Northern Plains... Scattered afternoon thunderstorm development appears probable as a weak shortwave trough interacts with the deeply mixed and destabilized airmass across the region. Low-level flow will be weak, but moderate westerly mid-level flow atop these modest southerlies will result in moderate vertical shear (i.e. effective bulk shear around 40 kt), which should be sufficient for updraft organization and a few supercells. Steep mid-level lapse rates will support the potential for large to very large hail, particularly within the earlier, more discrete storms. A transition to a more linear character is possible during the evening as cold pools amalgamate. Damaging gusts are the primary threat with line segments. The severe-weather threat is expected to wane shortly after sunset given increasing inhibition and the low-level jet being displaced well southeast. ...Mid MS Valley into the Lower/Middle OH Valley... Showers and thunderstorms will be likely be ongoing early Monday morning, remnant from overnight development and supported by the low-level jet (and associated warm-air advection). These storms will likely dissipate throughout the morning as the low-level jet weaken, but associated cloud cover and tempered heating could help support the development of an effective warm front in the northern IL/central IN/southern OH vicinity. Convergence along this boundary, combined with ascent attendant to the convectively enhanced shortwave trough/vorticity maximum expected to be progressing southeastward throughout the region, will likely result in renewed thunderstorm development during the afternoon and evening. Modest vertical shear should result in predominantly multicellular mode, but some stronger shear is possible closer to the vorticity maximum, and the potential exists for a few more organized storms. Damaging gusts are the primary hazard, but hail and even a brief tornado are possible as well. Mesoscale details will strongly influence where the greatest severe potential exists, precluding the confidence needed to introduce higher severe probabilities across the region with this outlook. A few afternoon/evening storms are also possible farther north across central/southern WI as a subtle shortwave trough moves across the region. Weak shear should preclude storm organization, but a few precipitation-loaded downbursts are possible. ..Mosier.. 07/28/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1227 PM CDT Sun Jul 28 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN PLAINS... ...SUMMARY... Scattered strong to severe storms are possible in portions of the Midwest and the northern Plains on Monday. ...Synopsis... Upper ridging is expected to become established from the southern Plains into the Gulf of Mexico on Monday, with modest upper troughing across the Pacific Northwest and an upper low off the coast of southern New England. Some enhanced westerly/northwesterly flow aloft is anticipated between the Pacific Northwest trough and the New England cyclone, extending from the northern Great Basin into the Upper/Mid MS Valley. A pair of shortwave troughs will likely be embedded within this stronger flow, a convectively augmented shortwave expected to begin the period over the Mid MS Valley and a low-amplitude wave expected to develop during the afternoon over the northern High Plains. The convectively augmented shortwave is forecast to continue southeastward across the middle OH Valley throughout the day while the developing wave continues eastward across the northern Plains. A complex surface pattern will likely be in place early Monday, with several areas of low pressure expected to be embedded within a broad area of troughing extending from the Upper Midwest through the central Plains. A moist airmass will exist east of the modest surface trough extending between these lows. ...Northern Plains... Scattered afternoon thunderstorm development appears probable as a weak shortwave trough interacts with the deeply mixed and destabilized airmass across the region. Low-level flow will be weak, but moderate westerly mid-level flow atop these modest southerlies will result in moderate vertical shear (i.e. effective bulk shear around 40 kt), which should be sufficient for updraft organization and a few supercells. Steep mid-level lapse rates will support the potential for large to very large hail, particularly within the earlier, more discrete storms. A transition to a more linear character is possible during the evening as cold pools amalgamate. Damaging gusts are the primary threat with line segments. The severe-weather threat is expected to wane shortly after sunset given increasing inhibition and the low-level jet being displaced well southeast. ...Mid MS Valley into the Lower/Middle OH Valley... Showers and thunderstorms will be likely be ongoing early Monday morning, remnant from overnight development and supported by the low-level jet (and associated warm-air advection). These storms will likely dissipate throughout the morning as the low-level jet weaken, but associated cloud cover and tempered heating could help support the development of an effective warm front in the northern IL/central IN/southern OH vicinity. Convergence along this boundary, combined with ascent attendant to the convectively enhanced shortwave trough/vorticity maximum expected to be progressing southeastward throughout the region, will likely result in renewed thunderstorm development during the afternoon and evening. Modest vertical shear should result in predominantly multicellular mode, but some stronger shear is possible closer to the vorticity maximum, and the potential exists for a few more organized storms. Damaging gusts are the primary hazard, but hail and even a brief tornado are possible as well. Mesoscale details will strongly influence where the greatest severe potential exists, precluding the confidence needed to introduce higher severe probabilities across the region with this outlook. A few afternoon/evening storms are also possible farther north across central/southern WI as a subtle shortwave trough moves across the region. Weak shear should preclude storm organization, but a few precipitation-loaded downbursts are possible. ..Mosier.. 07/28/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1227 PM CDT Sun Jul 28 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN PLAINS... ...SUMMARY... Scattered strong to severe storms are possible in portions of the Midwest and the northern Plains on Monday. ...Synopsis... Upper ridging is expected to become established from the southern Plains into the Gulf of Mexico on Monday, with modest upper troughing across the Pacific Northwest and an upper low off the coast of southern New England. Some enhanced westerly/northwesterly flow aloft is anticipated between the Pacific Northwest trough and the New England cyclone, extending from the northern Great Basin into the Upper/Mid MS Valley. A pair of shortwave troughs will likely be embedded within this stronger flow, a convectively augmented shortwave expected to begin the period over the Mid MS Valley and a low-amplitude wave expected to develop during the afternoon over the northern High Plains. The convectively augmented shortwave is forecast to continue southeastward across the middle OH Valley throughout the day while the developing wave continues eastward across the northern Plains. A complex surface pattern will likely be in place early Monday, with several areas of low pressure expected to be embedded within a broad area of troughing extending from the Upper Midwest through the central Plains. A moist airmass will exist east of the modest surface trough extending between these lows. ...Northern Plains... Scattered afternoon thunderstorm development appears probable as a weak shortwave trough interacts with the deeply mixed and destabilized airmass across the region. Low-level flow will be weak, but moderate westerly mid-level flow atop these modest southerlies will result in moderate vertical shear (i.e. effective bulk shear around 40 kt), which should be sufficient for updraft organization and a few supercells. Steep mid-level lapse rates will support the potential for large to very large hail, particularly within the earlier, more discrete storms. A transition to a more linear character is possible during the evening as cold pools amalgamate. Damaging gusts are the primary threat with line segments. The severe-weather threat is expected to wane shortly after sunset given increasing inhibition and the low-level jet being displaced well southeast. ...Mid MS Valley into the Lower/Middle OH Valley... Showers and thunderstorms will be likely be ongoing early Monday morning, remnant from overnight development and supported by the low-level jet (and associated warm-air advection). These storms will likely dissipate throughout the morning as the low-level jet weaken, but associated cloud cover and tempered heating could help support the development of an effective warm front in the northern IL/central IN/southern OH vicinity. Convergence along this boundary, combined with ascent attendant to the convectively enhanced shortwave trough/vorticity maximum expected to be progressing southeastward throughout the region, will likely result in renewed thunderstorm development during the afternoon and evening. Modest vertical shear should result in predominantly multicellular mode, but some stronger shear is possible closer to the vorticity maximum, and the potential exists for a few more organized storms. Damaging gusts are the primary hazard, but hail and even a brief tornado are possible as well. Mesoscale details will strongly influence where the greatest severe potential exists, precluding the confidence needed to introduce higher severe probabilities across the region with this outlook. A few afternoon/evening storms are also possible farther north across central/southern WI as a subtle shortwave trough moves across the region. Weak shear should preclude storm organization, but a few precipitation-loaded downbursts are possible. ..Mosier.. 07/28/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1227 PM CDT Sun Jul 28 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN PLAINS... ...SUMMARY... Scattered strong to severe storms are possible in portions of the Midwest and the northern Plains on Monday. ...Synopsis... Upper ridging is expected to become established from the southern Plains into the Gulf of Mexico on Monday, with modest upper troughing across the Pacific Northwest and an upper low off the coast of southern New England. Some enhanced westerly/northwesterly flow aloft is anticipated between the Pacific Northwest trough and the New England cyclone, extending from the northern Great Basin into the Upper/Mid MS Valley. A pair of shortwave troughs will likely be embedded within this stronger flow, a convectively augmented shortwave expected to begin the period over the Mid MS Valley and a low-amplitude wave expected to develop during the afternoon over the northern High Plains. The convectively augmented shortwave is forecast to continue southeastward across the middle OH Valley throughout the day while the developing wave continues eastward across the northern Plains. A complex surface pattern will likely be in place early Monday, with several areas of low pressure expected to be embedded within a broad area of troughing extending from the Upper Midwest through the central Plains. A moist airmass will exist east of the modest surface trough extending between these lows. ...Northern Plains... Scattered afternoon thunderstorm development appears probable as a weak shortwave trough interacts with the deeply mixed and destabilized airmass across the region. Low-level flow will be weak, but moderate westerly mid-level flow atop these modest southerlies will result in moderate vertical shear (i.e. effective bulk shear around 40 kt), which should be sufficient for updraft organization and a few supercells. Steep mid-level lapse rates will support the potential for large to very large hail, particularly within the earlier, more discrete storms. A transition to a more linear character is possible during the evening as cold pools amalgamate. Damaging gusts are the primary threat with line segments. The severe-weather threat is expected to wane shortly after sunset given increasing inhibition and the low-level jet being displaced well southeast. ...Mid MS Valley into the Lower/Middle OH Valley... Showers and thunderstorms will be likely be ongoing early Monday morning, remnant from overnight development and supported by the low-level jet (and associated warm-air advection). These storms will likely dissipate throughout the morning as the low-level jet weaken, but associated cloud cover and tempered heating could help support the development of an effective warm front in the northern IL/central IN/southern OH vicinity. Convergence along this boundary, combined with ascent attendant to the convectively enhanced shortwave trough/vorticity maximum expected to be progressing southeastward throughout the region, will likely result in renewed thunderstorm development during the afternoon and evening. Modest vertical shear should result in predominantly multicellular mode, but some stronger shear is possible closer to the vorticity maximum, and the potential exists for a few more organized storms. Damaging gusts are the primary hazard, but hail and even a brief tornado are possible as well. Mesoscale details will strongly influence where the greatest severe potential exists, precluding the confidence needed to introduce higher severe probabilities across the region with this outlook. A few afternoon/evening storms are also possible farther north across central/southern WI as a subtle shortwave trough moves across the region. Weak shear should preclude storm organization, but a few precipitation-loaded downbursts are possible. ..Mosier.. 07/28/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1227 PM CDT Sun Jul 28 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN PLAINS... ...SUMMARY... Scattered strong to severe storms are possible in portions of the Midwest and the northern Plains on Monday. ...Synopsis... Upper ridging is expected to become established from the southern Plains into the Gulf of Mexico on Monday, with modest upper troughing across the Pacific Northwest and an upper low off the coast of southern New England. Some enhanced westerly/northwesterly flow aloft is anticipated between the Pacific Northwest trough and the New England cyclone, extending from the northern Great Basin into the Upper/Mid MS Valley. A pair of shortwave troughs will likely be embedded within this stronger flow, a convectively augmented shortwave expected to begin the period over the Mid MS Valley and a low-amplitude wave expected to develop during the afternoon over the northern High Plains. The convectively augmented shortwave is forecast to continue southeastward across the middle OH Valley throughout the day while the developing wave continues eastward across the northern Plains. A complex surface pattern will likely be in place early Monday, with several areas of low pressure expected to be embedded within a broad area of troughing extending from the Upper Midwest through the central Plains. A moist airmass will exist east of the modest surface trough extending between these lows. ...Northern Plains... Scattered afternoon thunderstorm development appears probable as a weak shortwave trough interacts with the deeply mixed and destabilized airmass across the region. Low-level flow will be weak, but moderate westerly mid-level flow atop these modest southerlies will result in moderate vertical shear (i.e. effective bulk shear around 40 kt), which should be sufficient for updraft organization and a few supercells. Steep mid-level lapse rates will support the potential for large to very large hail, particularly within the earlier, more discrete storms. A transition to a more linear character is possible during the evening as cold pools amalgamate. Damaging gusts are the primary threat with line segments. The severe-weather threat is expected to wane shortly after sunset given increasing inhibition and the low-level jet being displaced well southeast. ...Mid MS Valley into the Lower/Middle OH Valley... Showers and thunderstorms will be likely be ongoing early Monday morning, remnant from overnight development and supported by the low-level jet (and associated warm-air advection). These storms will likely dissipate throughout the morning as the low-level jet weaken, but associated cloud cover and tempered heating could help support the development of an effective warm front in the northern IL/central IN/southern OH vicinity. Convergence along this boundary, combined with ascent attendant to the convectively enhanced shortwave trough/vorticity maximum expected to be progressing southeastward throughout the region, will likely result in renewed thunderstorm development during the afternoon and evening. Modest vertical shear should result in predominantly multicellular mode, but some stronger shear is possible closer to the vorticity maximum, and the potential exists for a few more organized storms. Damaging gusts are the primary hazard, but hail and even a brief tornado are possible as well. Mesoscale details will strongly influence where the greatest severe potential exists, precluding the confidence needed to introduce higher severe probabilities across the region with this outlook. A few afternoon/evening storms are also possible farther north across central/southern WI as a subtle shortwave trough moves across the region. Weak shear should preclude storm organization, but a few precipitation-loaded downbursts are possible. ..Mosier.. 07/28/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1227 PM CDT Sun Jul 28 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN PLAINS... ...SUMMARY... Scattered strong to severe storms are possible in portions of the Midwest and the northern Plains on Monday. ...Synopsis... Upper ridging is expected to become established from the southern Plains into the Gulf of Mexico on Monday, with modest upper troughing across the Pacific Northwest and an upper low off the coast of southern New England. Some enhanced westerly/northwesterly flow aloft is anticipated between the Pacific Northwest trough and the New England cyclone, extending from the northern Great Basin into the Upper/Mid MS Valley. A pair of shortwave troughs will likely be embedded within this stronger flow, a convectively augmented shortwave expected to begin the period over the Mid MS Valley and a low-amplitude wave expected to develop during the afternoon over the northern High Plains. The convectively augmented shortwave is forecast to continue southeastward across the middle OH Valley throughout the day while the developing wave continues eastward across the northern Plains. A complex surface pattern will likely be in place early Monday, with several areas of low pressure expected to be embedded within a broad area of troughing extending from the Upper Midwest through the central Plains. A moist airmass will exist east of the modest surface trough extending between these lows. ...Northern Plains... Scattered afternoon thunderstorm development appears probable as a weak shortwave trough interacts with the deeply mixed and destabilized airmass across the region. Low-level flow will be weak, but moderate westerly mid-level flow atop these modest southerlies will result in moderate vertical shear (i.e. effective bulk shear around 40 kt), which should be sufficient for updraft organization and a few supercells. Steep mid-level lapse rates will support the potential for large to very large hail, particularly within the earlier, more discrete storms. A transition to a more linear character is possible during the evening as cold pools amalgamate. Damaging gusts are the primary threat with line segments. The severe-weather threat is expected to wane shortly after sunset given increasing inhibition and the low-level jet being displaced well southeast. ...Mid MS Valley into the Lower/Middle OH Valley... Showers and thunderstorms will be likely be ongoing early Monday morning, remnant from overnight development and supported by the low-level jet (and associated warm-air advection). These storms will likely dissipate throughout the morning as the low-level jet weaken, but associated cloud cover and tempered heating could help support the development of an effective warm front in the northern IL/central IN/southern OH vicinity. Convergence along this boundary, combined with ascent attendant to the convectively enhanced shortwave trough/vorticity maximum expected to be progressing southeastward throughout the region, will likely result in renewed thunderstorm development during the afternoon and evening. Modest vertical shear should result in predominantly multicellular mode, but some stronger shear is possible closer to the vorticity maximum, and the potential exists for a few more organized storms. Damaging gusts are the primary hazard, but hail and even a brief tornado are possible as well. Mesoscale details will strongly influence where the greatest severe potential exists, precluding the confidence needed to introduce higher severe probabilities across the region with this outlook. A few afternoon/evening storms are also possible farther north across central/southern WI as a subtle shortwave trough moves across the region. Weak shear should preclude storm organization, but a few precipitation-loaded downbursts are possible. ..Mosier.. 07/28/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1227 PM CDT Sun Jul 28 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN PLAINS... ...SUMMARY... Scattered strong to severe storms are possible in portions of the Midwest and the northern Plains on Monday. ...Synopsis... Upper ridging is expected to become established from the southern Plains into the Gulf of Mexico on Monday, with modest upper troughing across the Pacific Northwest and an upper low off the coast of southern New England. Some enhanced westerly/northwesterly flow aloft is anticipated between the Pacific Northwest trough and the New England cyclone, extending from the northern Great Basin into the Upper/Mid MS Valley. A pair of shortwave troughs will likely be embedded within this stronger flow, a convectively augmented shortwave expected to begin the period over the Mid MS Valley and a low-amplitude wave expected to develop during the afternoon over the northern High Plains. The convectively augmented shortwave is forecast to continue southeastward across the middle OH Valley throughout the day while the developing wave continues eastward across the northern Plains. A complex surface pattern will likely be in place early Monday, with several areas of low pressure expected to be embedded within a broad area of troughing extending from the Upper Midwest through the central Plains. A moist airmass will exist east of the modest surface trough extending between these lows. ...Northern Plains... Scattered afternoon thunderstorm development appears probable as a weak shortwave trough interacts with the deeply mixed and destabilized airmass across the region. Low-level flow will be weak, but moderate westerly mid-level flow atop these modest southerlies will result in moderate vertical shear (i.e. effective bulk shear around 40 kt), which should be sufficient for updraft organization and a few supercells. Steep mid-level lapse rates will support the potential for large to very large hail, particularly within the earlier, more discrete storms. A transition to a more linear character is possible during the evening as cold pools amalgamate. Damaging gusts are the primary threat with line segments. The severe-weather threat is expected to wane shortly after sunset given increasing inhibition and the low-level jet being displaced well southeast. ...Mid MS Valley into the Lower/Middle OH Valley... Showers and thunderstorms will be likely be ongoing early Monday morning, remnant from overnight development and supported by the low-level jet (and associated warm-air advection). These storms will likely dissipate throughout the morning as the low-level jet weaken, but associated cloud cover and tempered heating could help support the development of an effective warm front in the northern IL/central IN/southern OH vicinity. Convergence along this boundary, combined with ascent attendant to the convectively enhanced shortwave trough/vorticity maximum expected to be progressing southeastward throughout the region, will likely result in renewed thunderstorm development during the afternoon and evening. Modest vertical shear should result in predominantly multicellular mode, but some stronger shear is possible closer to the vorticity maximum, and the potential exists for a few more organized storms. Damaging gusts are the primary hazard, but hail and even a brief tornado are possible as well. Mesoscale details will strongly influence where the greatest severe potential exists, precluding the confidence needed to introduce higher severe probabilities across the region with this outlook. A few afternoon/evening storms are also possible farther north across central/southern WI as a subtle shortwave trough moves across the region. Weak shear should preclude storm organization, but a few precipitation-loaded downbursts are possible. ..Mosier.. 07/28/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1227 PM CDT Sun Jul 28 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN PLAINS... ...SUMMARY... Scattered strong to severe storms are possible in portions of the Midwest and the northern Plains on Monday. ...Synopsis... Upper ridging is expected to become established from the southern Plains into the Gulf of Mexico on Monday, with modest upper troughing across the Pacific Northwest and an upper low off the coast of southern New England. Some enhanced westerly/northwesterly flow aloft is anticipated between the Pacific Northwest trough and the New England cyclone, extending from the northern Great Basin into the Upper/Mid MS Valley. A pair of shortwave troughs will likely be embedded within this stronger flow, a convectively augmented shortwave expected to begin the period over the Mid MS Valley and a low-amplitude wave expected to develop during the afternoon over the northern High Plains. The convectively augmented shortwave is forecast to continue southeastward across the middle OH Valley throughout the day while the developing wave continues eastward across the northern Plains. A complex surface pattern will likely be in place early Monday, with several areas of low pressure expected to be embedded within a broad area of troughing extending from the Upper Midwest through the central Plains. A moist airmass will exist east of the modest surface trough extending between these lows. ...Northern Plains... Scattered afternoon thunderstorm development appears probable as a weak shortwave trough interacts with the deeply mixed and destabilized airmass across the region. Low-level flow will be weak, but moderate westerly mid-level flow atop these modest southerlies will result in moderate vertical shear (i.e. effective bulk shear around 40 kt), which should be sufficient for updraft organization and a few supercells. Steep mid-level lapse rates will support the potential for large to very large hail, particularly within the earlier, more discrete storms. A transition to a more linear character is possible during the evening as cold pools amalgamate. Damaging gusts are the primary threat with line segments. The severe-weather threat is expected to wane shortly after sunset given increasing inhibition and the low-level jet being displaced well southeast. ...Mid MS Valley into the Lower/Middle OH Valley... Showers and thunderstorms will be likely be ongoing early Monday morning, remnant from overnight development and supported by the low-level jet (and associated warm-air advection). These storms will likely dissipate throughout the morning as the low-level jet weaken, but associated cloud cover and tempered heating could help support the development of an effective warm front in the northern IL/central IN/southern OH vicinity. Convergence along this boundary, combined with ascent attendant to the convectively enhanced shortwave trough/vorticity maximum expected to be progressing southeastward throughout the region, will likely result in renewed thunderstorm development during the afternoon and evening. Modest vertical shear should result in predominantly multicellular mode, but some stronger shear is possible closer to the vorticity maximum, and the potential exists for a few more organized storms. Damaging gusts are the primary hazard, but hail and even a brief tornado are possible as well. Mesoscale details will strongly influence where the greatest severe potential exists, precluding the confidence needed to introduce higher severe probabilities across the region with this outlook. A few afternoon/evening storms are also possible farther north across central/southern WI as a subtle shortwave trough moves across the region. Weak shear should preclude storm organization, but a few precipitation-loaded downbursts are possible. ..Mosier.. 07/28/2024 Read more

938
ABPZ20 KNHC 281721
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 AM PDT Sun Jul 28 2024

For the eastern North Pacific...east of 140 degrees west longitude:

South of Southern Mexico:
A large area of disorganized showers and thunderstorms located a few
hundred miles south of the southern coast of Mexico is associated
with a tropical wave. Environmental conditions appear conducive for
gradual development of this system, and a tropical depression is
likely to form during the middle part of the week. The system is
forecast to move westward to west-northwestward at 10 to 15 mph
during the next several days, remaining offshore of the southern
coast of Mexico.
* Formation chance through 48 hours...low...20 percent.
* Formation chance through 7 days...high...70 percent.

Western East Pacific:
An area of low pressure could form by the middle of the week well to
the southwest of the southern tip of the Baja California Peninsula.
Some slow development of this system is possible during the middle
and latter parts of the week while it moves westward to
west-northwestward across the western portion of the basin.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...low...30 percent.

South of Central America and Southern Mexico:
Another area of low pressure could form offshore of the coast of
Central America and southern Mexico towards the end of the week.
Some gradual development of this system is possible thereafter while
it moves generally westward.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...low...30 percent.

$$
Forecaster Kelly

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Sun Jul 28 2024 Valid 281630Z - 291200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS AND UPPER MIDWEST... ...SUMMARY... Scattered strong to severe thunderstorms are expected across parts of the northern/central Plains into the Upper Midwest this afternoon through tonight. Large hail and severe/damaging winds should be the main threats. ...Synopsis... Multiple low-amplitude, mid-level vorticity maxima (some convectively augmented) will move generally east-northeastward across the northern/central Plains and Upper Midwest through the period. One or more of these features should aid in robust thunderstorm development later today, although details on convective evolution through tonight remain uncertain. At the surface, a weak low over central SD late this morning should consolidate through this afternoon along/near the south-central SD/north-central NE border vicinity. A cold front will extend from northern MN into the Dakotas, linking with this surface low. A weak lee trough/dryline feature will extend southward from the low across parts of western/central NE/KS. ...Northern/Central Plains into the Upper Midwest... Scattered thunderstorms should develop across parts of western/central SD by late afternoon along/near the cold front and surface low. Although deep-layer shear appears marginal for supercells, any initially more discrete thunderstorms could produce severe hail. A fairly quick transition to a more linear mode with greater severe/damaging wind threat is anticipated through the evening as convection spreads eastward into central/eastern SD. With sufficient cold pool organization, some chance for isolated 75+ mph wind gusts may exist with this cluster. A gradual weakening trend is expected tonight as this activity moves into a less unstable airmass across southern MN/northern IA. A generally separate area of convection should form along the length of the front in MN this afternoon. Most of this area will be in a relative minimum in mid-level flow, with modest deep-layer shear. Still, some threat for hail and strong to severe winds may exist with any cluster that can consolidate and spread east-southeastward through the evening. Farther south into the central Plains (western/central NE/KS), large-scale forcing for ascent appears more nebulous, with a broad area of modestly enhanced mid-level westerly flow expected. Primary forcing mechanism for convective initiation should be weak low-level convergence along the lee surface trough. Assuming thunderstorms can form and be sustained, a conditionally favorable environment for severe wind gusts and hail will exist. Modest low-level flow is forecast to veer to a westerly component and gradually strengthen with height through mid levels, supporting sufficient deep-layer shear for supercells. Isolated large hail will be a concern with any persistent supercell, but a well-mixed boundary layer should also promote severe downdraft winds. Overall coverage of severe thunderstorms may tend to remain fairly isolated with southward extent given the weak forcing. ...Eastern Nebraska into Iowa and Northern Missouri... A remnant MCV is located over northeast NE late this morning per recent visible satellite and radar imagery. This feature should continue moving slowly eastward into western IA this afternoon. An associated modest low-level jet and attendant warm/moist advection may encourage additional robust thunderstorm development later today across parts of east-central NE into western/southern IA. Sufficient low-level shear will be present to support some tornado threat, but the potential for supercells remains highly uncertain. A somewhat better chance is apparent for a small cluster to develop and spread east-southeastward through the evening along the instability axis, while posing a threat for mainly damaging winds. Given this potential shown in some high-resolution guidance, the Slight Risk has been expanded east-southeastward to include more of east-central NE into southwest IA. ...Wyoming/Southern Montana... High-based convection is expected to develop this afternoon across parts of WY and southern MT ahead of a mid-level shortwave trough moving eastward from the Pacific Northwest. A couple of stronger outflow-driven cells/clusters appear possible, with an associated threat for isolated severe gusts. ...Tennessee Valley into the Southeast... Numerous thunderstorms are expected to further increase across parts of the TN Valley and Southeast this afternoon in association with a weak mid/upper-level trough moving northeastward across the mid MS Valley. Somewhat stronger heating and mid-level flow along the southern periphery of this trough could support a few strong thunderstorms, including the possibility of localized tree damage. However, with generally modest deep-layer shear and weak mid-level lapse rates, the potential for an organized/sustained severe threat across this region should remain rather limited. ..Gleason/Moore.. 07/28/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Sun Jul 28 2024 Valid 281630Z - 291200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS AND UPPER MIDWEST... ...SUMMARY... Scattered strong to severe thunderstorms are expected across parts of the northern/central Plains into the Upper Midwest this afternoon through tonight. Large hail and severe/damaging winds should be the main threats. ...Synopsis... Multiple low-amplitude, mid-level vorticity maxima (some convectively augmented) will move generally east-northeastward across the northern/central Plains and Upper Midwest through the period. One or more of these features should aid in robust thunderstorm development later today, although details on convective evolution through tonight remain uncertain. At the surface, a weak low over central SD late this morning should consolidate through this afternoon along/near the south-central SD/north-central NE border vicinity. A cold front will extend from northern MN into the Dakotas, linking with this surface low. A weak lee trough/dryline feature will extend southward from the low across parts of western/central NE/KS. ...Northern/Central Plains into the Upper Midwest... Scattered thunderstorms should develop across parts of western/central SD by late afternoon along/near the cold front and surface low. Although deep-layer shear appears marginal for supercells, any initially more discrete thunderstorms could produce severe hail. A fairly quick transition to a more linear mode with greater severe/damaging wind threat is anticipated through the evening as convection spreads eastward into central/eastern SD. With sufficient cold pool organization, some chance for isolated 75+ mph wind gusts may exist with this cluster. A gradual weakening trend is expected tonight as this activity moves into a less unstable airmass across southern MN/northern IA. A generally separate area of convection should form along the length of the front in MN this afternoon. Most of this area will be in a relative minimum in mid-level flow, with modest deep-layer shear. Still, some threat for hail and strong to severe winds may exist with any cluster that can consolidate and spread east-southeastward through the evening. Farther south into the central Plains (western/central NE/KS), large-scale forcing for ascent appears more nebulous, with a broad area of modestly enhanced mid-level westerly flow expected. Primary forcing mechanism for convective initiation should be weak low-level convergence along the lee surface trough. Assuming thunderstorms can form and be sustained, a conditionally favorable environment for severe wind gusts and hail will exist. Modest low-level flow is forecast to veer to a westerly component and gradually strengthen with height through mid levels, supporting sufficient deep-layer shear for supercells. Isolated large hail will be a concern with any persistent supercell, but a well-mixed boundary layer should also promote severe downdraft winds. Overall coverage of severe thunderstorms may tend to remain fairly isolated with southward extent given the weak forcing. ...Eastern Nebraska into Iowa and Northern Missouri... A remnant MCV is located over northeast NE late this morning per recent visible satellite and radar imagery. This feature should continue moving slowly eastward into western IA this afternoon. An associated modest low-level jet and attendant warm/moist advection may encourage additional robust thunderstorm development later today across parts of east-central NE into western/southern IA. Sufficient low-level shear will be present to support some tornado threat, but the potential for supercells remains highly uncertain. A somewhat better chance is apparent for a small cluster to develop and spread east-southeastward through the evening along the instability axis, while posing a threat for mainly damaging winds. Given this potential shown in some high-resolution guidance, the Slight Risk has been expanded east-southeastward to include more of east-central NE into southwest IA. ...Wyoming/Southern Montana... High-based convection is expected to develop this afternoon across parts of WY and southern MT ahead of a mid-level shortwave trough moving eastward from the Pacific Northwest. A couple of stronger outflow-driven cells/clusters appear possible, with an associated threat for isolated severe gusts. ...Tennessee Valley into the Southeast... Numerous thunderstorms are expected to further increase across parts of the TN Valley and Southeast this afternoon in association with a weak mid/upper-level trough moving northeastward across the mid MS Valley. Somewhat stronger heating and mid-level flow along the southern periphery of this trough could support a few strong thunderstorms, including the possibility of localized tree damage. However, with generally modest deep-layer shear and weak mid-level lapse rates, the potential for an organized/sustained severe threat across this region should remain rather limited. ..Gleason/Moore.. 07/28/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Sun Jul 28 2024 Valid 281630Z - 291200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS AND UPPER MIDWEST... ...SUMMARY... Scattered strong to severe thunderstorms are expected across parts of the northern/central Plains into the Upper Midwest this afternoon through tonight. Large hail and severe/damaging winds should be the main threats. ...Synopsis... Multiple low-amplitude, mid-level vorticity maxima (some convectively augmented) will move generally east-northeastward across the northern/central Plains and Upper Midwest through the period. One or more of these features should aid in robust thunderstorm development later today, although details on convective evolution through tonight remain uncertain. At the surface, a weak low over central SD late this morning should consolidate through this afternoon along/near the south-central SD/north-central NE border vicinity. A cold front will extend from northern MN into the Dakotas, linking with this surface low. A weak lee trough/dryline feature will extend southward from the low across parts of western/central NE/KS. ...Northern/Central Plains into the Upper Midwest... Scattered thunderstorms should develop across parts of western/central SD by late afternoon along/near the cold front and surface low. Although deep-layer shear appears marginal for supercells, any initially more discrete thunderstorms could produce severe hail. A fairly quick transition to a more linear mode with greater severe/damaging wind threat is anticipated through the evening as convection spreads eastward into central/eastern SD. With sufficient cold pool organization, some chance for isolated 75+ mph wind gusts may exist with this cluster. A gradual weakening trend is expected tonight as this activity moves into a less unstable airmass across southern MN/northern IA. A generally separate area of convection should form along the length of the front in MN this afternoon. Most of this area will be in a relative minimum in mid-level flow, with modest deep-layer shear. Still, some threat for hail and strong to severe winds may exist with any cluster that can consolidate and spread east-southeastward through the evening. Farther south into the central Plains (western/central NE/KS), large-scale forcing for ascent appears more nebulous, with a broad area of modestly enhanced mid-level westerly flow expected. Primary forcing mechanism for convective initiation should be weak low-level convergence along the lee surface trough. Assuming thunderstorms can form and be sustained, a conditionally favorable environment for severe wind gusts and hail will exist. Modest low-level flow is forecast to veer to a westerly component and gradually strengthen with height through mid levels, supporting sufficient deep-layer shear for supercells. Isolated large hail will be a concern with any persistent supercell, but a well-mixed boundary layer should also promote severe downdraft winds. Overall coverage of severe thunderstorms may tend to remain fairly isolated with southward extent given the weak forcing. ...Eastern Nebraska into Iowa and Northern Missouri... A remnant MCV is located over northeast NE late this morning per recent visible satellite and radar imagery. This feature should continue moving slowly eastward into western IA this afternoon. An associated modest low-level jet and attendant warm/moist advection may encourage additional robust thunderstorm development later today across parts of east-central NE into western/southern IA. Sufficient low-level shear will be present to support some tornado threat, but the potential for supercells remains highly uncertain. A somewhat better chance is apparent for a small cluster to develop and spread east-southeastward through the evening along the instability axis, while posing a threat for mainly damaging winds. Given this potential shown in some high-resolution guidance, the Slight Risk has been expanded east-southeastward to include more of east-central NE into southwest IA. ...Wyoming/Southern Montana... High-based convection is expected to develop this afternoon across parts of WY and southern MT ahead of a mid-level shortwave trough moving eastward from the Pacific Northwest. A couple of stronger outflow-driven cells/clusters appear possible, with an associated threat for isolated severe gusts. ...Tennessee Valley into the Southeast... Numerous thunderstorms are expected to further increase across parts of the TN Valley and Southeast this afternoon in association with a weak mid/upper-level trough moving northeastward across the mid MS Valley. Somewhat stronger heating and mid-level flow along the southern periphery of this trough could support a few strong thunderstorms, including the possibility of localized tree damage. However, with generally modest deep-layer shear and weak mid-level lapse rates, the potential for an organized/sustained severe threat across this region should remain rather limited. ..Gleason/Moore.. 07/28/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Sun Jul 28 2024 Valid 281630Z - 291200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS AND UPPER MIDWEST... ...SUMMARY... Scattered strong to severe thunderstorms are expected across parts of the northern/central Plains into the Upper Midwest this afternoon through tonight. Large hail and severe/damaging winds should be the main threats. ...Synopsis... Multiple low-amplitude, mid-level vorticity maxima (some convectively augmented) will move generally east-northeastward across the northern/central Plains and Upper Midwest through the period. One or more of these features should aid in robust thunderstorm development later today, although details on convective evolution through tonight remain uncertain. At the surface, a weak low over central SD late this morning should consolidate through this afternoon along/near the south-central SD/north-central NE border vicinity. A cold front will extend from northern MN into the Dakotas, linking with this surface low. A weak lee trough/dryline feature will extend southward from the low across parts of western/central NE/KS. ...Northern/Central Plains into the Upper Midwest... Scattered thunderstorms should develop across parts of western/central SD by late afternoon along/near the cold front and surface low. Although deep-layer shear appears marginal for supercells, any initially more discrete thunderstorms could produce severe hail. A fairly quick transition to a more linear mode with greater severe/damaging wind threat is anticipated through the evening as convection spreads eastward into central/eastern SD. With sufficient cold pool organization, some chance for isolated 75+ mph wind gusts may exist with this cluster. A gradual weakening trend is expected tonight as this activity moves into a less unstable airmass across southern MN/northern IA. A generally separate area of convection should form along the length of the front in MN this afternoon. Most of this area will be in a relative minimum in mid-level flow, with modest deep-layer shear. Still, some threat for hail and strong to severe winds may exist with any cluster that can consolidate and spread east-southeastward through the evening. Farther south into the central Plains (western/central NE/KS), large-scale forcing for ascent appears more nebulous, with a broad area of modestly enhanced mid-level westerly flow expected. Primary forcing mechanism for convective initiation should be weak low-level convergence along the lee surface trough. Assuming thunderstorms can form and be sustained, a conditionally favorable environment for severe wind gusts and hail will exist. Modest low-level flow is forecast to veer to a westerly component and gradually strengthen with height through mid levels, supporting sufficient deep-layer shear for supercells. Isolated large hail will be a concern with any persistent supercell, but a well-mixed boundary layer should also promote severe downdraft winds. Overall coverage of severe thunderstorms may tend to remain fairly isolated with southward extent given the weak forcing. ...Eastern Nebraska into Iowa and Northern Missouri... A remnant MCV is located over northeast NE late this morning per recent visible satellite and radar imagery. This feature should continue moving slowly eastward into western IA this afternoon. An associated modest low-level jet and attendant warm/moist advection may encourage additional robust thunderstorm development later today across parts of east-central NE into western/southern IA. Sufficient low-level shear will be present to support some tornado threat, but the potential for supercells remains highly uncertain. A somewhat better chance is apparent for a small cluster to develop and spread east-southeastward through the evening along the instability axis, while posing a threat for mainly damaging winds. Given this potential shown in some high-resolution guidance, the Slight Risk has been expanded east-southeastward to include more of east-central NE into southwest IA. ...Wyoming/Southern Montana... High-based convection is expected to develop this afternoon across parts of WY and southern MT ahead of a mid-level shortwave trough moving eastward from the Pacific Northwest. A couple of stronger outflow-driven cells/clusters appear possible, with an associated threat for isolated severe gusts. ...Tennessee Valley into the Southeast... Numerous thunderstorms are expected to further increase across parts of the TN Valley and Southeast this afternoon in association with a weak mid/upper-level trough moving northeastward across the mid MS Valley. Somewhat stronger heating and mid-level flow along the southern periphery of this trough could support a few strong thunderstorms, including the possibility of localized tree damage. However, with generally modest deep-layer shear and weak mid-level lapse rates, the potential for an organized/sustained severe threat across this region should remain rather limited. ..Gleason/Moore.. 07/28/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Sun Jul 28 2024 Valid 281630Z - 291200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS AND UPPER MIDWEST... ...SUMMARY... Scattered strong to severe thunderstorms are expected across parts of the northern/central Plains into the Upper Midwest this afternoon through tonight. Large hail and severe/damaging winds should be the main threats. ...Synopsis... Multiple low-amplitude, mid-level vorticity maxima (some convectively augmented) will move generally east-northeastward across the northern/central Plains and Upper Midwest through the period. One or more of these features should aid in robust thunderstorm development later today, although details on convective evolution through tonight remain uncertain. At the surface, a weak low over central SD late this morning should consolidate through this afternoon along/near the south-central SD/north-central NE border vicinity. A cold front will extend from northern MN into the Dakotas, linking with this surface low. A weak lee trough/dryline feature will extend southward from the low across parts of western/central NE/KS. ...Northern/Central Plains into the Upper Midwest... Scattered thunderstorms should develop across parts of western/central SD by late afternoon along/near the cold front and surface low. Although deep-layer shear appears marginal for supercells, any initially more discrete thunderstorms could produce severe hail. A fairly quick transition to a more linear mode with greater severe/damaging wind threat is anticipated through the evening as convection spreads eastward into central/eastern SD. With sufficient cold pool organization, some chance for isolated 75+ mph wind gusts may exist with this cluster. A gradual weakening trend is expected tonight as this activity moves into a less unstable airmass across southern MN/northern IA. A generally separate area of convection should form along the length of the front in MN this afternoon. Most of this area will be in a relative minimum in mid-level flow, with modest deep-layer shear. Still, some threat for hail and strong to severe winds may exist with any cluster that can consolidate and spread east-southeastward through the evening. Farther south into the central Plains (western/central NE/KS), large-scale forcing for ascent appears more nebulous, with a broad area of modestly enhanced mid-level westerly flow expected. Primary forcing mechanism for convective initiation should be weak low-level convergence along the lee surface trough. Assuming thunderstorms can form and be sustained, a conditionally favorable environment for severe wind gusts and hail will exist. Modest low-level flow is forecast to veer to a westerly component and gradually strengthen with height through mid levels, supporting sufficient deep-layer shear for supercells. Isolated large hail will be a concern with any persistent supercell, but a well-mixed boundary layer should also promote severe downdraft winds. Overall coverage of severe thunderstorms may tend to remain fairly isolated with southward extent given the weak forcing. ...Eastern Nebraska into Iowa and Northern Missouri... A remnant MCV is located over northeast NE late this morning per recent visible satellite and radar imagery. This feature should continue moving slowly eastward into western IA this afternoon. An associated modest low-level jet and attendant warm/moist advection may encourage additional robust thunderstorm development later today across parts of east-central NE into western/southern IA. Sufficient low-level shear will be present to support some tornado threat, but the potential for supercells remains highly uncertain. A somewhat better chance is apparent for a small cluster to develop and spread east-southeastward through the evening along the instability axis, while posing a threat for mainly damaging winds. Given this potential shown in some high-resolution guidance, the Slight Risk has been expanded east-southeastward to include more of east-central NE into southwest IA. ...Wyoming/Southern Montana... High-based convection is expected to develop this afternoon across parts of WY and southern MT ahead of a mid-level shortwave trough moving eastward from the Pacific Northwest. A couple of stronger outflow-driven cells/clusters appear possible, with an associated threat for isolated severe gusts. ...Tennessee Valley into the Southeast... Numerous thunderstorms are expected to further increase across parts of the TN Valley and Southeast this afternoon in association with a weak mid/upper-level trough moving northeastward across the mid MS Valley. Somewhat stronger heating and mid-level flow along the southern periphery of this trough could support a few strong thunderstorms, including the possibility of localized tree damage. However, with generally modest deep-layer shear and weak mid-level lapse rates, the potential for an organized/sustained severe threat across this region should remain rather limited. ..Gleason/Moore.. 07/28/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Sun Jul 28 2024 Valid 281630Z - 291200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS AND UPPER MIDWEST... ...SUMMARY... Scattered strong to severe thunderstorms are expected across parts of the northern/central Plains into the Upper Midwest this afternoon through tonight. Large hail and severe/damaging winds should be the main threats. ...Synopsis... Multiple low-amplitude, mid-level vorticity maxima (some convectively augmented) will move generally east-northeastward across the northern/central Plains and Upper Midwest through the period. One or more of these features should aid in robust thunderstorm development later today, although details on convective evolution through tonight remain uncertain. At the surface, a weak low over central SD late this morning should consolidate through this afternoon along/near the south-central SD/north-central NE border vicinity. A cold front will extend from northern MN into the Dakotas, linking with this surface low. A weak lee trough/dryline feature will extend southward from the low across parts of western/central NE/KS. ...Northern/Central Plains into the Upper Midwest... Scattered thunderstorms should develop across parts of western/central SD by late afternoon along/near the cold front and surface low. Although deep-layer shear appears marginal for supercells, any initially more discrete thunderstorms could produce severe hail. A fairly quick transition to a more linear mode with greater severe/damaging wind threat is anticipated through the evening as convection spreads eastward into central/eastern SD. With sufficient cold pool organization, some chance for isolated 75+ mph wind gusts may exist with this cluster. A gradual weakening trend is expected tonight as this activity moves into a less unstable airmass across southern MN/northern IA. A generally separate area of convection should form along the length of the front in MN this afternoon. Most of this area will be in a relative minimum in mid-level flow, with modest deep-layer shear. Still, some threat for hail and strong to severe winds may exist with any cluster that can consolidate and spread east-southeastward through the evening. Farther south into the central Plains (western/central NE/KS), large-scale forcing for ascent appears more nebulous, with a broad area of modestly enhanced mid-level westerly flow expected. Primary forcing mechanism for convective initiation should be weak low-level convergence along the lee surface trough. Assuming thunderstorms can form and be sustained, a conditionally favorable environment for severe wind gusts and hail will exist. Modest low-level flow is forecast to veer to a westerly component and gradually strengthen with height through mid levels, supporting sufficient deep-layer shear for supercells. Isolated large hail will be a concern with any persistent supercell, but a well-mixed boundary layer should also promote severe downdraft winds. Overall coverage of severe thunderstorms may tend to remain fairly isolated with southward extent given the weak forcing. ...Eastern Nebraska into Iowa and Northern Missouri... A remnant MCV is located over northeast NE late this morning per recent visible satellite and radar imagery. This feature should continue moving slowly eastward into western IA this afternoon. An associated modest low-level jet and attendant warm/moist advection may encourage additional robust thunderstorm development later today across parts of east-central NE into western/southern IA. Sufficient low-level shear will be present to support some tornado threat, but the potential for supercells remains highly uncertain. A somewhat better chance is apparent for a small cluster to develop and spread east-southeastward through the evening along the instability axis, while posing a threat for mainly damaging winds. Given this potential shown in some high-resolution guidance, the Slight Risk has been expanded east-southeastward to include more of east-central NE into southwest IA. ...Wyoming/Southern Montana... High-based convection is expected to develop this afternoon across parts of WY and southern MT ahead of a mid-level shortwave trough moving eastward from the Pacific Northwest. A couple of stronger outflow-driven cells/clusters appear possible, with an associated threat for isolated severe gusts. ...Tennessee Valley into the Southeast... Numerous thunderstorms are expected to further increase across parts of the TN Valley and Southeast this afternoon in association with a weak mid/upper-level trough moving northeastward across the mid MS Valley. Somewhat stronger heating and mid-level flow along the southern periphery of this trough could support a few strong thunderstorms, including the possibility of localized tree damage. However, with generally modest deep-layer shear and weak mid-level lapse rates, the potential for an organized/sustained severe threat across this region should remain rather limited. ..Gleason/Moore.. 07/28/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Sun Jul 28 2024 Valid 281630Z - 291200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS AND UPPER MIDWEST... ...SUMMARY... Scattered strong to severe thunderstorms are expected across parts of the northern/central Plains into the Upper Midwest this afternoon through tonight. Large hail and severe/damaging winds should be the main threats. ...Synopsis... Multiple low-amplitude, mid-level vorticity maxima (some convectively augmented) will move generally east-northeastward across the northern/central Plains and Upper Midwest through the period. One or more of these features should aid in robust thunderstorm development later today, although details on convective evolution through tonight remain uncertain. At the surface, a weak low over central SD late this morning should consolidate through this afternoon along/near the south-central SD/north-central NE border vicinity. A cold front will extend from northern MN into the Dakotas, linking with this surface low. A weak lee trough/dryline feature will extend southward from the low across parts of western/central NE/KS. ...Northern/Central Plains into the Upper Midwest... Scattered thunderstorms should develop across parts of western/central SD by late afternoon along/near the cold front and surface low. Although deep-layer shear appears marginal for supercells, any initially more discrete thunderstorms could produce severe hail. A fairly quick transition to a more linear mode with greater severe/damaging wind threat is anticipated through the evening as convection spreads eastward into central/eastern SD. With sufficient cold pool organization, some chance for isolated 75+ mph wind gusts may exist with this cluster. A gradual weakening trend is expected tonight as this activity moves into a less unstable airmass across southern MN/northern IA. A generally separate area of convection should form along the length of the front in MN this afternoon. Most of this area will be in a relative minimum in mid-level flow, with modest deep-layer shear. Still, some threat for hail and strong to severe winds may exist with any cluster that can consolidate and spread east-southeastward through the evening. Farther south into the central Plains (western/central NE/KS), large-scale forcing for ascent appears more nebulous, with a broad area of modestly enhanced mid-level westerly flow expected. Primary forcing mechanism for convective initiation should be weak low-level convergence along the lee surface trough. Assuming thunderstorms can form and be sustained, a conditionally favorable environment for severe wind gusts and hail will exist. Modest low-level flow is forecast to veer to a westerly component and gradually strengthen with height through mid levels, supporting sufficient deep-layer shear for supercells. Isolated large hail will be a concern with any persistent supercell, but a well-mixed boundary layer should also promote severe downdraft winds. Overall coverage of severe thunderstorms may tend to remain fairly isolated with southward extent given the weak forcing. ...Eastern Nebraska into Iowa and Northern Missouri... A remnant MCV is located over northeast NE late this morning per recent visible satellite and radar imagery. This feature should continue moving slowly eastward into western IA this afternoon. An associated modest low-level jet and attendant warm/moist advection may encourage additional robust thunderstorm development later today across parts of east-central NE into western/southern IA. Sufficient low-level shear will be present to support some tornado threat, but the potential for supercells remains highly uncertain. A somewhat better chance is apparent for a small cluster to develop and spread east-southeastward through the evening along the instability axis, while posing a threat for mainly damaging winds. Given this potential shown in some high-resolution guidance, the Slight Risk has been expanded east-southeastward to include more of east-central NE into southwest IA. ...Wyoming/Southern Montana... High-based convection is expected to develop this afternoon across parts of WY and southern MT ahead of a mid-level shortwave trough moving eastward from the Pacific Northwest. A couple of stronger outflow-driven cells/clusters appear possible, with an associated threat for isolated severe gusts. ...Tennessee Valley into the Southeast... Numerous thunderstorms are expected to further increase across parts of the TN Valley and Southeast this afternoon in association with a weak mid/upper-level trough moving northeastward across the mid MS Valley. Somewhat stronger heating and mid-level flow along the southern periphery of this trough could support a few strong thunderstorms, including the possibility of localized tree damage. However, with generally modest deep-layer shear and weak mid-level lapse rates, the potential for an organized/sustained severe threat across this region should remain rather limited. ..Gleason/Moore.. 07/28/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Sun Jul 28 2024 Valid 281630Z - 291200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS AND UPPER MIDWEST... ...SUMMARY... Scattered strong to severe thunderstorms are expected across parts of the northern/central Plains into the Upper Midwest this afternoon through tonight. Large hail and severe/damaging winds should be the main threats. ...Synopsis... Multiple low-amplitude, mid-level vorticity maxima (some convectively augmented) will move generally east-northeastward across the northern/central Plains and Upper Midwest through the period. One or more of these features should aid in robust thunderstorm development later today, although details on convective evolution through tonight remain uncertain. At the surface, a weak low over central SD late this morning should consolidate through this afternoon along/near the south-central SD/north-central NE border vicinity. A cold front will extend from northern MN into the Dakotas, linking with this surface low. A weak lee trough/dryline feature will extend southward from the low across parts of western/central NE/KS. ...Northern/Central Plains into the Upper Midwest... Scattered thunderstorms should develop across parts of western/central SD by late afternoon along/near the cold front and surface low. Although deep-layer shear appears marginal for supercells, any initially more discrete thunderstorms could produce severe hail. A fairly quick transition to a more linear mode with greater severe/damaging wind threat is anticipated through the evening as convection spreads eastward into central/eastern SD. With sufficient cold pool organization, some chance for isolated 75+ mph wind gusts may exist with this cluster. A gradual weakening trend is expected tonight as this activity moves into a less unstable airmass across southern MN/northern IA. A generally separate area of convection should form along the length of the front in MN this afternoon. Most of this area will be in a relative minimum in mid-level flow, with modest deep-layer shear. Still, some threat for hail and strong to severe winds may exist with any cluster that can consolidate and spread east-southeastward through the evening. Farther south into the central Plains (western/central NE/KS), large-scale forcing for ascent appears more nebulous, with a broad area of modestly enhanced mid-level westerly flow expected. Primary forcing mechanism for convective initiation should be weak low-level convergence along the lee surface trough. Assuming thunderstorms can form and be sustained, a conditionally favorable environment for severe wind gusts and hail will exist. Modest low-level flow is forecast to veer to a westerly component and gradually strengthen with height through mid levels, supporting sufficient deep-layer shear for supercells. Isolated large hail will be a concern with any persistent supercell, but a well-mixed boundary layer should also promote severe downdraft winds. Overall coverage of severe thunderstorms may tend to remain fairly isolated with southward extent given the weak forcing. ...Eastern Nebraska into Iowa and Northern Missouri... A remnant MCV is located over northeast NE late this morning per recent visible satellite and radar imagery. This feature should continue moving slowly eastward into western IA this afternoon. An associated modest low-level jet and attendant warm/moist advection may encourage additional robust thunderstorm development later today across parts of east-central NE into western/southern IA. Sufficient low-level shear will be present to support some tornado threat, but the potential for supercells remains highly uncertain. A somewhat better chance is apparent for a small cluster to develop and spread east-southeastward through the evening along the instability axis, while posing a threat for mainly damaging winds. Given this potential shown in some high-resolution guidance, the Slight Risk has been expanded east-southeastward to include more of east-central NE into southwest IA. ...Wyoming/Southern Montana... High-based convection is expected to develop this afternoon across parts of WY and southern MT ahead of a mid-level shortwave trough moving eastward from the Pacific Northwest. A couple of stronger outflow-driven cells/clusters appear possible, with an associated threat for isolated severe gusts. ...Tennessee Valley into the Southeast... Numerous thunderstorms are expected to further increase across parts of the TN Valley and Southeast this afternoon in association with a weak mid/upper-level trough moving northeastward across the mid MS Valley. Somewhat stronger heating and mid-level flow along the southern periphery of this trough could support a few strong thunderstorms, including the possibility of localized tree damage. However, with generally modest deep-layer shear and weak mid-level lapse rates, the potential for an organized/sustained severe threat across this region should remain rather limited. ..Gleason/Moore.. 07/28/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Sun Jul 28 2024 Valid 281630Z - 291200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS AND UPPER MIDWEST... ...SUMMARY... Scattered strong to severe thunderstorms are expected across parts of the northern/central Plains into the Upper Midwest this afternoon through tonight. Large hail and severe/damaging winds should be the main threats. ...Synopsis... Multiple low-amplitude, mid-level vorticity maxima (some convectively augmented) will move generally east-northeastward across the northern/central Plains and Upper Midwest through the period. One or more of these features should aid in robust thunderstorm development later today, although details on convective evolution through tonight remain uncertain. At the surface, a weak low over central SD late this morning should consolidate through this afternoon along/near the south-central SD/north-central NE border vicinity. A cold front will extend from northern MN into the Dakotas, linking with this surface low. A weak lee trough/dryline feature will extend southward from the low across parts of western/central NE/KS. ...Northern/Central Plains into the Upper Midwest... Scattered thunderstorms should develop across parts of western/central SD by late afternoon along/near the cold front and surface low. Although deep-layer shear appears marginal for supercells, any initially more discrete thunderstorms could produce severe hail. A fairly quick transition to a more linear mode with greater severe/damaging wind threat is anticipated through the evening as convection spreads eastward into central/eastern SD. With sufficient cold pool organization, some chance for isolated 75+ mph wind gusts may exist with this cluster. A gradual weakening trend is expected tonight as this activity moves into a less unstable airmass across southern MN/northern IA. A generally separate area of convection should form along the length of the front in MN this afternoon. Most of this area will be in a relative minimum in mid-level flow, with modest deep-layer shear. Still, some threat for hail and strong to severe winds may exist with any cluster that can consolidate and spread east-southeastward through the evening. Farther south into the central Plains (western/central NE/KS), large-scale forcing for ascent appears more nebulous, with a broad area of modestly enhanced mid-level westerly flow expected. Primary forcing mechanism for convective initiation should be weak low-level convergence along the lee surface trough. Assuming thunderstorms can form and be sustained, a conditionally favorable environment for severe wind gusts and hail will exist. Modest low-level flow is forecast to veer to a westerly component and gradually strengthen with height through mid levels, supporting sufficient deep-layer shear for supercells. Isolated large hail will be a concern with any persistent supercell, but a well-mixed boundary layer should also promote severe downdraft winds. Overall coverage of severe thunderstorms may tend to remain fairly isolated with southward extent given the weak forcing. ...Eastern Nebraska into Iowa and Northern Missouri... A remnant MCV is located over northeast NE late this morning per recent visible satellite and radar imagery. This feature should continue moving slowly eastward into western IA this afternoon. An associated modest low-level jet and attendant warm/moist advection may encourage additional robust thunderstorm development later today across parts of east-central NE into western/southern IA. Sufficient low-level shear will be present to support some tornado threat, but the potential for supercells remains highly uncertain. A somewhat better chance is apparent for a small cluster to develop and spread east-southeastward through the evening along the instability axis, while posing a threat for mainly damaging winds. Given this potential shown in some high-resolution guidance, the Slight Risk has been expanded east-southeastward to include more of east-central NE into southwest IA. ...Wyoming/Southern Montana... High-based convection is expected to develop this afternoon across parts of WY and southern MT ahead of a mid-level shortwave trough moving eastward from the Pacific Northwest. A couple of stronger outflow-driven cells/clusters appear possible, with an associated threat for isolated severe gusts. ...Tennessee Valley into the Southeast... Numerous thunderstorms are expected to further increase across parts of the TN Valley and Southeast this afternoon in association with a weak mid/upper-level trough moving northeastward across the mid MS Valley. Somewhat stronger heating and mid-level flow along the southern periphery of this trough could support a few strong thunderstorms, including the possibility of localized tree damage. However, with generally modest deep-layer shear and weak mid-level lapse rates, the potential for an organized/sustained severe threat across this region should remain rather limited. ..Gleason/Moore.. 07/28/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Sun Jul 28 2024 Valid 281630Z - 291200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS AND UPPER MIDWEST... ...SUMMARY... Scattered strong to severe thunderstorms are expected across parts of the northern/central Plains into the Upper Midwest this afternoon through tonight. Large hail and severe/damaging winds should be the main threats. ...Synopsis... Multiple low-amplitude, mid-level vorticity maxima (some convectively augmented) will move generally east-northeastward across the northern/central Plains and Upper Midwest through the period. One or more of these features should aid in robust thunderstorm development later today, although details on convective evolution through tonight remain uncertain. At the surface, a weak low over central SD late this morning should consolidate through this afternoon along/near the south-central SD/north-central NE border vicinity. A cold front will extend from northern MN into the Dakotas, linking with this surface low. A weak lee trough/dryline feature will extend southward from the low across parts of western/central NE/KS. ...Northern/Central Plains into the Upper Midwest... Scattered thunderstorms should develop across parts of western/central SD by late afternoon along/near the cold front and surface low. Although deep-layer shear appears marginal for supercells, any initially more discrete thunderstorms could produce severe hail. A fairly quick transition to a more linear mode with greater severe/damaging wind threat is anticipated through the evening as convection spreads eastward into central/eastern SD. With sufficient cold pool organization, some chance for isolated 75+ mph wind gusts may exist with this cluster. A gradual weakening trend is expected tonight as this activity moves into a less unstable airmass across southern MN/northern IA. A generally separate area of convection should form along the length of the front in MN this afternoon. Most of this area will be in a relative minimum in mid-level flow, with modest deep-layer shear. Still, some threat for hail and strong to severe winds may exist with any cluster that can consolidate and spread east-southeastward through the evening. Farther south into the central Plains (western/central NE/KS), large-scale forcing for ascent appears more nebulous, with a broad area of modestly enhanced mid-level westerly flow expected. Primary forcing mechanism for convective initiation should be weak low-level convergence along the lee surface trough. Assuming thunderstorms can form and be sustained, a conditionally favorable environment for severe wind gusts and hail will exist. Modest low-level flow is forecast to veer to a westerly component and gradually strengthen with height through mid levels, supporting sufficient deep-layer shear for supercells. Isolated large hail will be a concern with any persistent supercell, but a well-mixed boundary layer should also promote severe downdraft winds. Overall coverage of severe thunderstorms may tend to remain fairly isolated with southward extent given the weak forcing. ...Eastern Nebraska into Iowa and Northern Missouri... A remnant MCV is located over northeast NE late this morning per recent visible satellite and radar imagery. This feature should continue moving slowly eastward into western IA this afternoon. An associated modest low-level jet and attendant warm/moist advection may encourage additional robust thunderstorm development later today across parts of east-central NE into western/southern IA. Sufficient low-level shear will be present to support some tornado threat, but the potential for supercells remains highly uncertain. A somewhat better chance is apparent for a small cluster to develop and spread east-southeastward through the evening along the instability axis, while posing a threat for mainly damaging winds. Given this potential shown in some high-resolution guidance, the Slight Risk has been expanded east-southeastward to include more of east-central NE into southwest IA. ...Wyoming/Southern Montana... High-based convection is expected to develop this afternoon across parts of WY and southern MT ahead of a mid-level shortwave trough moving eastward from the Pacific Northwest. A couple of stronger outflow-driven cells/clusters appear possible, with an associated threat for isolated severe gusts. ...Tennessee Valley into the Southeast... Numerous thunderstorms are expected to further increase across parts of the TN Valley and Southeast this afternoon in association with a weak mid/upper-level trough moving northeastward across the mid MS Valley. Somewhat stronger heating and mid-level flow along the southern periphery of this trough could support a few strong thunderstorms, including the possibility of localized tree damage. However, with generally modest deep-layer shear and weak mid-level lapse rates, the potential for an organized/sustained severe threat across this region should remain rather limited. ..Gleason/Moore.. 07/28/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Sun Jul 28 2024 Valid 281630Z - 291200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS AND UPPER MIDWEST... ...SUMMARY... Scattered strong to severe thunderstorms are expected across parts of the northern/central Plains into the Upper Midwest this afternoon through tonight. Large hail and severe/damaging winds should be the main threats. ...Synopsis... Multiple low-amplitude, mid-level vorticity maxima (some convectively augmented) will move generally east-northeastward across the northern/central Plains and Upper Midwest through the period. One or more of these features should aid in robust thunderstorm development later today, although details on convective evolution through tonight remain uncertain. At the surface, a weak low over central SD late this morning should consolidate through this afternoon along/near the south-central SD/north-central NE border vicinity. A cold front will extend from northern MN into the Dakotas, linking with this surface low. A weak lee trough/dryline feature will extend southward from the low across parts of western/central NE/KS. ...Northern/Central Plains into the Upper Midwest... Scattered thunderstorms should develop across parts of western/central SD by late afternoon along/near the cold front and surface low. Although deep-layer shear appears marginal for supercells, any initially more discrete thunderstorms could produce severe hail. A fairly quick transition to a more linear mode with greater severe/damaging wind threat is anticipated through the evening as convection spreads eastward into central/eastern SD. With sufficient cold pool organization, some chance for isolated 75+ mph wind gusts may exist with this cluster. A gradual weakening trend is expected tonight as this activity moves into a less unstable airmass across southern MN/northern IA. A generally separate area of convection should form along the length of the front in MN this afternoon. Most of this area will be in a relative minimum in mid-level flow, with modest deep-layer shear. Still, some threat for hail and strong to severe winds may exist with any cluster that can consolidate and spread east-southeastward through the evening. Farther south into the central Plains (western/central NE/KS), large-scale forcing for ascent appears more nebulous, with a broad area of modestly enhanced mid-level westerly flow expected. Primary forcing mechanism for convective initiation should be weak low-level convergence along the lee surface trough. Assuming thunderstorms can form and be sustained, a conditionally favorable environment for severe wind gusts and hail will exist. Modest low-level flow is forecast to veer to a westerly component and gradually strengthen with height through mid levels, supporting sufficient deep-layer shear for supercells. Isolated large hail will be a concern with any persistent supercell, but a well-mixed boundary layer should also promote severe downdraft winds. Overall coverage of severe thunderstorms may tend to remain fairly isolated with southward extent given the weak forcing. ...Eastern Nebraska into Iowa and Northern Missouri... A remnant MCV is located over northeast NE late this morning per recent visible satellite and radar imagery. This feature should continue moving slowly eastward into western IA this afternoon. An associated modest low-level jet and attendant warm/moist advection may encourage additional robust thunderstorm development later today across parts of east-central NE into western/southern IA. Sufficient low-level shear will be present to support some tornado threat, but the potential for supercells remains highly uncertain. A somewhat better chance is apparent for a small cluster to develop and spread east-southeastward through the evening along the instability axis, while posing a threat for mainly damaging winds. Given this potential shown in some high-resolution guidance, the Slight Risk has been expanded east-southeastward to include more of east-central NE into southwest IA. ...Wyoming/Southern Montana... High-based convection is expected to develop this afternoon across parts of WY and southern MT ahead of a mid-level shortwave trough moving eastward from the Pacific Northwest. A couple of stronger outflow-driven cells/clusters appear possible, with an associated threat for isolated severe gusts. ...Tennessee Valley into the Southeast... Numerous thunderstorms are expected to further increase across parts of the TN Valley and Southeast this afternoon in association with a weak mid/upper-level trough moving northeastward across the mid MS Valley. Somewhat stronger heating and mid-level flow along the southern periphery of this trough could support a few strong thunderstorms, including the possibility of localized tree damage. However, with generally modest deep-layer shear and weak mid-level lapse rates, the potential for an organized/sustained severe threat across this region should remain rather limited. ..Gleason/Moore.. 07/28/2024 Read more