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SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0126 PM CDT Tue Aug 13 2024 Valid 141200Z - 151200Z An isolated dry thunderstorm risk area has been introduced for portions of far northern CA into OR. Latest guidance has come into better agreement regarding thunderstorm potential associated with an approaching trough. Thunderstorm chances should increase late afternoon into the overnight/early-morning hours across this region. Forecast soundings have also trended towards drier mid-level conditions with PWAT values between 0.6 to 0.8 inches. Given antecedent dry fuels, dry thunderstorms will be a fire concern. ..Moore.. 08/13/2024 .PREV DISCUSSION... /ISSUED 0157 AM CDT Tue Aug 13 2024/ ...Synopsis... A mid-level shortwave trough is expected to approach the northwestern California coast on D2/Wednesday, with much of the Western U.S. characterized by weak, zonal mid-level flow. This trough could bring some forcing for thunderstorm development overnight into Thursday morning across northern California into southern Oregon, but PWAT values > 0.8 and Most Unstable parcel originating at temps colder than 0C leave some uncertainty on where dry thunder highlights might be needed. Surface winds are forecast to remain well below Critical highlight criteria across the western U.S., though some locally Elevated fire-weather conditions are possible across portions of southern Nevada, northwest Arizona, and southern Utah. These conditions will be confined to local topography, and fuels across much of the southern Great Basin are not receptive enough to wildfire spread (due to recent wetting rainfall) to warrant highlights at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0126 PM CDT Tue Aug 13 2024 Valid 141200Z - 151200Z An isolated dry thunderstorm risk area has been introduced for portions of far northern CA into OR. Latest guidance has come into better agreement regarding thunderstorm potential associated with an approaching trough. Thunderstorm chances should increase late afternoon into the overnight/early-morning hours across this region. Forecast soundings have also trended towards drier mid-level conditions with PWAT values between 0.6 to 0.8 inches. Given antecedent dry fuels, dry thunderstorms will be a fire concern. ..Moore.. 08/13/2024 .PREV DISCUSSION... /ISSUED 0157 AM CDT Tue Aug 13 2024/ ...Synopsis... A mid-level shortwave trough is expected to approach the northwestern California coast on D2/Wednesday, with much of the Western U.S. characterized by weak, zonal mid-level flow. This trough could bring some forcing for thunderstorm development overnight into Thursday morning across northern California into southern Oregon, but PWAT values > 0.8 and Most Unstable parcel originating at temps colder than 0C leave some uncertainty on where dry thunder highlights might be needed. Surface winds are forecast to remain well below Critical highlight criteria across the western U.S., though some locally Elevated fire-weather conditions are possible across portions of southern Nevada, northwest Arizona, and southern Utah. These conditions will be confined to local topography, and fuels across much of the southern Great Basin are not receptive enough to wildfire spread (due to recent wetting rainfall) to warrant highlights at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0126 PM CDT Tue Aug 13 2024 Valid 141200Z - 151200Z An isolated dry thunderstorm risk area has been introduced for portions of far northern CA into OR. Latest guidance has come into better agreement regarding thunderstorm potential associated with an approaching trough. Thunderstorm chances should increase late afternoon into the overnight/early-morning hours across this region. Forecast soundings have also trended towards drier mid-level conditions with PWAT values between 0.6 to 0.8 inches. Given antecedent dry fuels, dry thunderstorms will be a fire concern. ..Moore.. 08/13/2024 .PREV DISCUSSION... /ISSUED 0157 AM CDT Tue Aug 13 2024/ ...Synopsis... A mid-level shortwave trough is expected to approach the northwestern California coast on D2/Wednesday, with much of the Western U.S. characterized by weak, zonal mid-level flow. This trough could bring some forcing for thunderstorm development overnight into Thursday morning across northern California into southern Oregon, but PWAT values > 0.8 and Most Unstable parcel originating at temps colder than 0C leave some uncertainty on where dry thunder highlights might be needed. Surface winds are forecast to remain well below Critical highlight criteria across the western U.S., though some locally Elevated fire-weather conditions are possible across portions of southern Nevada, northwest Arizona, and southern Utah. These conditions will be confined to local topography, and fuels across much of the southern Great Basin are not receptive enough to wildfire spread (due to recent wetting rainfall) to warrant highlights at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0126 PM CDT Tue Aug 13 2024 Valid 141200Z - 151200Z An isolated dry thunderstorm risk area has been introduced for portions of far northern CA into OR. Latest guidance has come into better agreement regarding thunderstorm potential associated with an approaching trough. Thunderstorm chances should increase late afternoon into the overnight/early-morning hours across this region. Forecast soundings have also trended towards drier mid-level conditions with PWAT values between 0.6 to 0.8 inches. Given antecedent dry fuels, dry thunderstorms will be a fire concern. ..Moore.. 08/13/2024 .PREV DISCUSSION... /ISSUED 0157 AM CDT Tue Aug 13 2024/ ...Synopsis... A mid-level shortwave trough is expected to approach the northwestern California coast on D2/Wednesday, with much of the Western U.S. characterized by weak, zonal mid-level flow. This trough could bring some forcing for thunderstorm development overnight into Thursday morning across northern California into southern Oregon, but PWAT values > 0.8 and Most Unstable parcel originating at temps colder than 0C leave some uncertainty on where dry thunder highlights might be needed. Surface winds are forecast to remain well below Critical highlight criteria across the western U.S., though some locally Elevated fire-weather conditions are possible across portions of southern Nevada, northwest Arizona, and southern Utah. These conditions will be confined to local topography, and fuels across much of the southern Great Basin are not receptive enough to wildfire spread (due to recent wetting rainfall) to warrant highlights at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0126 PM CDT Tue Aug 13 2024 Valid 141200Z - 151200Z An isolated dry thunderstorm risk area has been introduced for portions of far northern CA into OR. Latest guidance has come into better agreement regarding thunderstorm potential associated with an approaching trough. Thunderstorm chances should increase late afternoon into the overnight/early-morning hours across this region. Forecast soundings have also trended towards drier mid-level conditions with PWAT values between 0.6 to 0.8 inches. Given antecedent dry fuels, dry thunderstorms will be a fire concern. ..Moore.. 08/13/2024 .PREV DISCUSSION... /ISSUED 0157 AM CDT Tue Aug 13 2024/ ...Synopsis... A mid-level shortwave trough is expected to approach the northwestern California coast on D2/Wednesday, with much of the Western U.S. characterized by weak, zonal mid-level flow. This trough could bring some forcing for thunderstorm development overnight into Thursday morning across northern California into southern Oregon, but PWAT values > 0.8 and Most Unstable parcel originating at temps colder than 0C leave some uncertainty on where dry thunder highlights might be needed. Surface winds are forecast to remain well below Critical highlight criteria across the western U.S., though some locally Elevated fire-weather conditions are possible across portions of southern Nevada, northwest Arizona, and southern Utah. These conditions will be confined to local topography, and fuels across much of the southern Great Basin are not receptive enough to wildfire spread (due to recent wetting rainfall) to warrant highlights at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

000
ABPZ20 KNHC 131724
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 AM PDT Tue Aug 13 2024

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

Offshore Southwestern Mexico:
An area of low pressure could form this weekend well offshore of
southern Mexico. Some slow development is possible by early next
week as the low moves west-northwestward, remaining offshore of
southwestern Mexico.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...low...20 percent.

$$
Forecaster Hagen/Berg

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1220 PM CDT Tue Aug 13 2024 Valid 141200Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF EASTERN NE...WESTERN IA...NORTHEAST KS...NORTHWEST MO... ...SUMMARY... Isolated to scattered severe thunderstorms are possible Wednesday across parts of the northern/central Plains into the mid Missouri Valley, with greater potential for large hail, damaging winds, and a tornado or two across parts of northeast Kansas, eastern Nebraska, western Iowa, and northwest Missouri. ...Eastern NE/northeast KS into parts of IA/MO/southern MN... A mid/upper-level trough will move across the central/northern Great Plains towards the upper Midwest on Wednesday. Multiple vorticity maxima, and possibly one or more MCVs, will likely move through the larger-scale trough. The surface pattern will be similarly complex, with a general consensus for a consolidating surface low somewhere across central NE/KS by afternoon. Outflow and cloudiness from morning convection will influence the position of surface boundaries later in the day. One surface boundary that will serve as an effective warm front is forecast to move northward somewhere across northeast KS/northwest MO into eastern NE/western IA, though its position by afternoon/evening remains uncertain. A weak surface trough/cold front will move across parts of the Dakotas into central NE, with another surface trough potentially moving across KS/southeast NE and intersecting the warm front. Given the rather complex surface/upper-air pattern and influence of morning convection, storm evolution remains rather uncertain Wednesday afternoon and evening. From northeast KS/northwest MO into southeast NE/southwest IA, at least isolated storm development will be possible by late afternoon near the warm front and other surface boundaries. Modestly enhanced southwesterly flow aloft will support effective shear of 30-40 kt, and a couple of supercells could evolve from initial development, with a threat of large hail and damaging wind. Some tornado threat would also accompany any supercells near the warm front, especially into the evening when some increase in low-level flow and SRH is expected. With time, one or more upscale-growing clusters may develop, with an attendant threat of damaging gusts spreading eastward across parts of IA/MO. ...Dakotas into central NE... A few strong to locally severe storms will be possible across parts of the Dakotas into central NE. For the Dakotas, somewhat weaker instability and deep-layer shear is expected compared to areas to the south and east, but at least scattered storm development will be possible in conjunction with the mid/upper-level trough. Depending on the extent of heating/destabilization, isolated hail and strong/damaging gusts will be possible. Across central NE, instability and deep-layer shear may be somewhat stronger, though confidence regarding storm coverage decreases with southward extent. A conditional risk for hail and localized severe gusts will accompany any stronger storm in this area. ...Far eastern ID/UT into WY...northern/eastern CO...western KS...TX/OK Panhandles... Another round of relatively high-based convection appears possible Wednesday afternoon into the early evening from parts of eastern ID/UT into WY and northwest CO. Sufficient instability and modest westerly flow aloft could support a few stronger cells/clusters with strong to locally severe outflow winds. Isolated strong storms will also be possible from eastern CO into western KS, and potentially into the OK/TX Panhandle region. While this area will generally be displaced from stronger large-scale ascent, relatively strong heating, weak to moderate buoyancy, and modest deep-layer flow/shear could support a couple stronger cells/clusters capable of isolated strong/severe gusts and hail. ...Parts of New England... Isolated to widely scattered thunderstorms are possible Wednesday afternoon across parts of New England, along the western periphery of a midlevel low near the Canadian Maritimes. Deep-layer shear will generally be weak, but cold temperatures aloft and unidirectional northerly flow could support a few stronger southward-moving cells/clusters, with small hail and locally gusty winds. Confidence in a more organized severe threat is currently too low for probabilities. ..Dean.. 08/13/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1220 PM CDT Tue Aug 13 2024 Valid 141200Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF EASTERN NE...WESTERN IA...NORTHEAST KS...NORTHWEST MO... ...SUMMARY... Isolated to scattered severe thunderstorms are possible Wednesday across parts of the northern/central Plains into the mid Missouri Valley, with greater potential for large hail, damaging winds, and a tornado or two across parts of northeast Kansas, eastern Nebraska, western Iowa, and northwest Missouri. ...Eastern NE/northeast KS into parts of IA/MO/southern MN... A mid/upper-level trough will move across the central/northern Great Plains towards the upper Midwest on Wednesday. Multiple vorticity maxima, and possibly one or more MCVs, will likely move through the larger-scale trough. The surface pattern will be similarly complex, with a general consensus for a consolidating surface low somewhere across central NE/KS by afternoon. Outflow and cloudiness from morning convection will influence the position of surface boundaries later in the day. One surface boundary that will serve as an effective warm front is forecast to move northward somewhere across northeast KS/northwest MO into eastern NE/western IA, though its position by afternoon/evening remains uncertain. A weak surface trough/cold front will move across parts of the Dakotas into central NE, with another surface trough potentially moving across KS/southeast NE and intersecting the warm front. Given the rather complex surface/upper-air pattern and influence of morning convection, storm evolution remains rather uncertain Wednesday afternoon and evening. From northeast KS/northwest MO into southeast NE/southwest IA, at least isolated storm development will be possible by late afternoon near the warm front and other surface boundaries. Modestly enhanced southwesterly flow aloft will support effective shear of 30-40 kt, and a couple of supercells could evolve from initial development, with a threat of large hail and damaging wind. Some tornado threat would also accompany any supercells near the warm front, especially into the evening when some increase in low-level flow and SRH is expected. With time, one or more upscale-growing clusters may develop, with an attendant threat of damaging gusts spreading eastward across parts of IA/MO. ...Dakotas into central NE... A few strong to locally severe storms will be possible across parts of the Dakotas into central NE. For the Dakotas, somewhat weaker instability and deep-layer shear is expected compared to areas to the south and east, but at least scattered storm development will be possible in conjunction with the mid/upper-level trough. Depending on the extent of heating/destabilization, isolated hail and strong/damaging gusts will be possible. Across central NE, instability and deep-layer shear may be somewhat stronger, though confidence regarding storm coverage decreases with southward extent. A conditional risk for hail and localized severe gusts will accompany any stronger storm in this area. ...Far eastern ID/UT into WY...northern/eastern CO...western KS...TX/OK Panhandles... Another round of relatively high-based convection appears possible Wednesday afternoon into the early evening from parts of eastern ID/UT into WY and northwest CO. Sufficient instability and modest westerly flow aloft could support a few stronger cells/clusters with strong to locally severe outflow winds. Isolated strong storms will also be possible from eastern CO into western KS, and potentially into the OK/TX Panhandle region. While this area will generally be displaced from stronger large-scale ascent, relatively strong heating, weak to moderate buoyancy, and modest deep-layer flow/shear could support a couple stronger cells/clusters capable of isolated strong/severe gusts and hail. ...Parts of New England... Isolated to widely scattered thunderstorms are possible Wednesday afternoon across parts of New England, along the western periphery of a midlevel low near the Canadian Maritimes. Deep-layer shear will generally be weak, but cold temperatures aloft and unidirectional northerly flow could support a few stronger southward-moving cells/clusters, with small hail and locally gusty winds. Confidence in a more organized severe threat is currently too low for probabilities. ..Dean.. 08/13/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1220 PM CDT Tue Aug 13 2024 Valid 141200Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF EASTERN NE...WESTERN IA...NORTHEAST KS...NORTHWEST MO... ...SUMMARY... Isolated to scattered severe thunderstorms are possible Wednesday across parts of the northern/central Plains into the mid Missouri Valley, with greater potential for large hail, damaging winds, and a tornado or two across parts of northeast Kansas, eastern Nebraska, western Iowa, and northwest Missouri. ...Eastern NE/northeast KS into parts of IA/MO/southern MN... A mid/upper-level trough will move across the central/northern Great Plains towards the upper Midwest on Wednesday. Multiple vorticity maxima, and possibly one or more MCVs, will likely move through the larger-scale trough. The surface pattern will be similarly complex, with a general consensus for a consolidating surface low somewhere across central NE/KS by afternoon. Outflow and cloudiness from morning convection will influence the position of surface boundaries later in the day. One surface boundary that will serve as an effective warm front is forecast to move northward somewhere across northeast KS/northwest MO into eastern NE/western IA, though its position by afternoon/evening remains uncertain. A weak surface trough/cold front will move across parts of the Dakotas into central NE, with another surface trough potentially moving across KS/southeast NE and intersecting the warm front. Given the rather complex surface/upper-air pattern and influence of morning convection, storm evolution remains rather uncertain Wednesday afternoon and evening. From northeast KS/northwest MO into southeast NE/southwest IA, at least isolated storm development will be possible by late afternoon near the warm front and other surface boundaries. Modestly enhanced southwesterly flow aloft will support effective shear of 30-40 kt, and a couple of supercells could evolve from initial development, with a threat of large hail and damaging wind. Some tornado threat would also accompany any supercells near the warm front, especially into the evening when some increase in low-level flow and SRH is expected. With time, one or more upscale-growing clusters may develop, with an attendant threat of damaging gusts spreading eastward across parts of IA/MO. ...Dakotas into central NE... A few strong to locally severe storms will be possible across parts of the Dakotas into central NE. For the Dakotas, somewhat weaker instability and deep-layer shear is expected compared to areas to the south and east, but at least scattered storm development will be possible in conjunction with the mid/upper-level trough. Depending on the extent of heating/destabilization, isolated hail and strong/damaging gusts will be possible. Across central NE, instability and deep-layer shear may be somewhat stronger, though confidence regarding storm coverage decreases with southward extent. A conditional risk for hail and localized severe gusts will accompany any stronger storm in this area. ...Far eastern ID/UT into WY...northern/eastern CO...western KS...TX/OK Panhandles... Another round of relatively high-based convection appears possible Wednesday afternoon into the early evening from parts of eastern ID/UT into WY and northwest CO. Sufficient instability and modest westerly flow aloft could support a few stronger cells/clusters with strong to locally severe outflow winds. Isolated strong storms will also be possible from eastern CO into western KS, and potentially into the OK/TX Panhandle region. While this area will generally be displaced from stronger large-scale ascent, relatively strong heating, weak to moderate buoyancy, and modest deep-layer flow/shear could support a couple stronger cells/clusters capable of isolated strong/severe gusts and hail. ...Parts of New England... Isolated to widely scattered thunderstorms are possible Wednesday afternoon across parts of New England, along the western periphery of a midlevel low near the Canadian Maritimes. Deep-layer shear will generally be weak, but cold temperatures aloft and unidirectional northerly flow could support a few stronger southward-moving cells/clusters, with small hail and locally gusty winds. Confidence in a more organized severe threat is currently too low for probabilities. ..Dean.. 08/13/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1220 PM CDT Tue Aug 13 2024 Valid 141200Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF EASTERN NE...WESTERN IA...NORTHEAST KS...NORTHWEST MO... ...SUMMARY... Isolated to scattered severe thunderstorms are possible Wednesday across parts of the northern/central Plains into the mid Missouri Valley, with greater potential for large hail, damaging winds, and a tornado or two across parts of northeast Kansas, eastern Nebraska, western Iowa, and northwest Missouri. ...Eastern NE/northeast KS into parts of IA/MO/southern MN... A mid/upper-level trough will move across the central/northern Great Plains towards the upper Midwest on Wednesday. Multiple vorticity maxima, and possibly one or more MCVs, will likely move through the larger-scale trough. The surface pattern will be similarly complex, with a general consensus for a consolidating surface low somewhere across central NE/KS by afternoon. Outflow and cloudiness from morning convection will influence the position of surface boundaries later in the day. One surface boundary that will serve as an effective warm front is forecast to move northward somewhere across northeast KS/northwest MO into eastern NE/western IA, though its position by afternoon/evening remains uncertain. A weak surface trough/cold front will move across parts of the Dakotas into central NE, with another surface trough potentially moving across KS/southeast NE and intersecting the warm front. Given the rather complex surface/upper-air pattern and influence of morning convection, storm evolution remains rather uncertain Wednesday afternoon and evening. From northeast KS/northwest MO into southeast NE/southwest IA, at least isolated storm development will be possible by late afternoon near the warm front and other surface boundaries. Modestly enhanced southwesterly flow aloft will support effective shear of 30-40 kt, and a couple of supercells could evolve from initial development, with a threat of large hail and damaging wind. Some tornado threat would also accompany any supercells near the warm front, especially into the evening when some increase in low-level flow and SRH is expected. With time, one or more upscale-growing clusters may develop, with an attendant threat of damaging gusts spreading eastward across parts of IA/MO. ...Dakotas into central NE... A few strong to locally severe storms will be possible across parts of the Dakotas into central NE. For the Dakotas, somewhat weaker instability and deep-layer shear is expected compared to areas to the south and east, but at least scattered storm development will be possible in conjunction with the mid/upper-level trough. Depending on the extent of heating/destabilization, isolated hail and strong/damaging gusts will be possible. Across central NE, instability and deep-layer shear may be somewhat stronger, though confidence regarding storm coverage decreases with southward extent. A conditional risk for hail and localized severe gusts will accompany any stronger storm in this area. ...Far eastern ID/UT into WY...northern/eastern CO...western KS...TX/OK Panhandles... Another round of relatively high-based convection appears possible Wednesday afternoon into the early evening from parts of eastern ID/UT into WY and northwest CO. Sufficient instability and modest westerly flow aloft could support a few stronger cells/clusters with strong to locally severe outflow winds. Isolated strong storms will also be possible from eastern CO into western KS, and potentially into the OK/TX Panhandle region. While this area will generally be displaced from stronger large-scale ascent, relatively strong heating, weak to moderate buoyancy, and modest deep-layer flow/shear could support a couple stronger cells/clusters capable of isolated strong/severe gusts and hail. ...Parts of New England... Isolated to widely scattered thunderstorms are possible Wednesday afternoon across parts of New England, along the western periphery of a midlevel low near the Canadian Maritimes. Deep-layer shear will generally be weak, but cold temperatures aloft and unidirectional northerly flow could support a few stronger southward-moving cells/clusters, with small hail and locally gusty winds. Confidence in a more organized severe threat is currently too low for probabilities. ..Dean.. 08/13/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1220 PM CDT Tue Aug 13 2024 Valid 141200Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF EASTERN NE...WESTERN IA...NORTHEAST KS...NORTHWEST MO... ...SUMMARY... Isolated to scattered severe thunderstorms are possible Wednesday across parts of the northern/central Plains into the mid Missouri Valley, with greater potential for large hail, damaging winds, and a tornado or two across parts of northeast Kansas, eastern Nebraska, western Iowa, and northwest Missouri. ...Eastern NE/northeast KS into parts of IA/MO/southern MN... A mid/upper-level trough will move across the central/northern Great Plains towards the upper Midwest on Wednesday. Multiple vorticity maxima, and possibly one or more MCVs, will likely move through the larger-scale trough. The surface pattern will be similarly complex, with a general consensus for a consolidating surface low somewhere across central NE/KS by afternoon. Outflow and cloudiness from morning convection will influence the position of surface boundaries later in the day. One surface boundary that will serve as an effective warm front is forecast to move northward somewhere across northeast KS/northwest MO into eastern NE/western IA, though its position by afternoon/evening remains uncertain. A weak surface trough/cold front will move across parts of the Dakotas into central NE, with another surface trough potentially moving across KS/southeast NE and intersecting the warm front. Given the rather complex surface/upper-air pattern and influence of morning convection, storm evolution remains rather uncertain Wednesday afternoon and evening. From northeast KS/northwest MO into southeast NE/southwest IA, at least isolated storm development will be possible by late afternoon near the warm front and other surface boundaries. Modestly enhanced southwesterly flow aloft will support effective shear of 30-40 kt, and a couple of supercells could evolve from initial development, with a threat of large hail and damaging wind. Some tornado threat would also accompany any supercells near the warm front, especially into the evening when some increase in low-level flow and SRH is expected. With time, one or more upscale-growing clusters may develop, with an attendant threat of damaging gusts spreading eastward across parts of IA/MO. ...Dakotas into central NE... A few strong to locally severe storms will be possible across parts of the Dakotas into central NE. For the Dakotas, somewhat weaker instability and deep-layer shear is expected compared to areas to the south and east, but at least scattered storm development will be possible in conjunction with the mid/upper-level trough. Depending on the extent of heating/destabilization, isolated hail and strong/damaging gusts will be possible. Across central NE, instability and deep-layer shear may be somewhat stronger, though confidence regarding storm coverage decreases with southward extent. A conditional risk for hail and localized severe gusts will accompany any stronger storm in this area. ...Far eastern ID/UT into WY...northern/eastern CO...western KS...TX/OK Panhandles... Another round of relatively high-based convection appears possible Wednesday afternoon into the early evening from parts of eastern ID/UT into WY and northwest CO. Sufficient instability and modest westerly flow aloft could support a few stronger cells/clusters with strong to locally severe outflow winds. Isolated strong storms will also be possible from eastern CO into western KS, and potentially into the OK/TX Panhandle region. While this area will generally be displaced from stronger large-scale ascent, relatively strong heating, weak to moderate buoyancy, and modest deep-layer flow/shear could support a couple stronger cells/clusters capable of isolated strong/severe gusts and hail. ...Parts of New England... Isolated to widely scattered thunderstorms are possible Wednesday afternoon across parts of New England, along the western periphery of a midlevel low near the Canadian Maritimes. Deep-layer shear will generally be weak, but cold temperatures aloft and unidirectional northerly flow could support a few stronger southward-moving cells/clusters, with small hail and locally gusty winds. Confidence in a more organized severe threat is currently too low for probabilities. ..Dean.. 08/13/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1220 PM CDT Tue Aug 13 2024 Valid 141200Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF EASTERN NE...WESTERN IA...NORTHEAST KS...NORTHWEST MO... ...SUMMARY... Isolated to scattered severe thunderstorms are possible Wednesday across parts of the northern/central Plains into the mid Missouri Valley, with greater potential for large hail, damaging winds, and a tornado or two across parts of northeast Kansas, eastern Nebraska, western Iowa, and northwest Missouri. ...Eastern NE/northeast KS into parts of IA/MO/southern MN... A mid/upper-level trough will move across the central/northern Great Plains towards the upper Midwest on Wednesday. Multiple vorticity maxima, and possibly one or more MCVs, will likely move through the larger-scale trough. The surface pattern will be similarly complex, with a general consensus for a consolidating surface low somewhere across central NE/KS by afternoon. Outflow and cloudiness from morning convection will influence the position of surface boundaries later in the day. One surface boundary that will serve as an effective warm front is forecast to move northward somewhere across northeast KS/northwest MO into eastern NE/western IA, though its position by afternoon/evening remains uncertain. A weak surface trough/cold front will move across parts of the Dakotas into central NE, with another surface trough potentially moving across KS/southeast NE and intersecting the warm front. Given the rather complex surface/upper-air pattern and influence of morning convection, storm evolution remains rather uncertain Wednesday afternoon and evening. From northeast KS/northwest MO into southeast NE/southwest IA, at least isolated storm development will be possible by late afternoon near the warm front and other surface boundaries. Modestly enhanced southwesterly flow aloft will support effective shear of 30-40 kt, and a couple of supercells could evolve from initial development, with a threat of large hail and damaging wind. Some tornado threat would also accompany any supercells near the warm front, especially into the evening when some increase in low-level flow and SRH is expected. With time, one or more upscale-growing clusters may develop, with an attendant threat of damaging gusts spreading eastward across parts of IA/MO. ...Dakotas into central NE... A few strong to locally severe storms will be possible across parts of the Dakotas into central NE. For the Dakotas, somewhat weaker instability and deep-layer shear is expected compared to areas to the south and east, but at least scattered storm development will be possible in conjunction with the mid/upper-level trough. Depending on the extent of heating/destabilization, isolated hail and strong/damaging gusts will be possible. Across central NE, instability and deep-layer shear may be somewhat stronger, though confidence regarding storm coverage decreases with southward extent. A conditional risk for hail and localized severe gusts will accompany any stronger storm in this area. ...Far eastern ID/UT into WY...northern/eastern CO...western KS...TX/OK Panhandles... Another round of relatively high-based convection appears possible Wednesday afternoon into the early evening from parts of eastern ID/UT into WY and northwest CO. Sufficient instability and modest westerly flow aloft could support a few stronger cells/clusters with strong to locally severe outflow winds. Isolated strong storms will also be possible from eastern CO into western KS, and potentially into the OK/TX Panhandle region. While this area will generally be displaced from stronger large-scale ascent, relatively strong heating, weak to moderate buoyancy, and modest deep-layer flow/shear could support a couple stronger cells/clusters capable of isolated strong/severe gusts and hail. ...Parts of New England... Isolated to widely scattered thunderstorms are possible Wednesday afternoon across parts of New England, along the western periphery of a midlevel low near the Canadian Maritimes. Deep-layer shear will generally be weak, but cold temperatures aloft and unidirectional northerly flow could support a few stronger southward-moving cells/clusters, with small hail and locally gusty winds. Confidence in a more organized severe threat is currently too low for probabilities. ..Dean.. 08/13/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1220 PM CDT Tue Aug 13 2024 Valid 141200Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF EASTERN NE...WESTERN IA...NORTHEAST KS...NORTHWEST MO... ...SUMMARY... Isolated to scattered severe thunderstorms are possible Wednesday across parts of the northern/central Plains into the mid Missouri Valley, with greater potential for large hail, damaging winds, and a tornado or two across parts of northeast Kansas, eastern Nebraska, western Iowa, and northwest Missouri. ...Eastern NE/northeast KS into parts of IA/MO/southern MN... A mid/upper-level trough will move across the central/northern Great Plains towards the upper Midwest on Wednesday. Multiple vorticity maxima, and possibly one or more MCVs, will likely move through the larger-scale trough. The surface pattern will be similarly complex, with a general consensus for a consolidating surface low somewhere across central NE/KS by afternoon. Outflow and cloudiness from morning convection will influence the position of surface boundaries later in the day. One surface boundary that will serve as an effective warm front is forecast to move northward somewhere across northeast KS/northwest MO into eastern NE/western IA, though its position by afternoon/evening remains uncertain. A weak surface trough/cold front will move across parts of the Dakotas into central NE, with another surface trough potentially moving across KS/southeast NE and intersecting the warm front. Given the rather complex surface/upper-air pattern and influence of morning convection, storm evolution remains rather uncertain Wednesday afternoon and evening. From northeast KS/northwest MO into southeast NE/southwest IA, at least isolated storm development will be possible by late afternoon near the warm front and other surface boundaries. Modestly enhanced southwesterly flow aloft will support effective shear of 30-40 kt, and a couple of supercells could evolve from initial development, with a threat of large hail and damaging wind. Some tornado threat would also accompany any supercells near the warm front, especially into the evening when some increase in low-level flow and SRH is expected. With time, one or more upscale-growing clusters may develop, with an attendant threat of damaging gusts spreading eastward across parts of IA/MO. ...Dakotas into central NE... A few strong to locally severe storms will be possible across parts of the Dakotas into central NE. For the Dakotas, somewhat weaker instability and deep-layer shear is expected compared to areas to the south and east, but at least scattered storm development will be possible in conjunction with the mid/upper-level trough. Depending on the extent of heating/destabilization, isolated hail and strong/damaging gusts will be possible. Across central NE, instability and deep-layer shear may be somewhat stronger, though confidence regarding storm coverage decreases with southward extent. A conditional risk for hail and localized severe gusts will accompany any stronger storm in this area. ...Far eastern ID/UT into WY...northern/eastern CO...western KS...TX/OK Panhandles... Another round of relatively high-based convection appears possible Wednesday afternoon into the early evening from parts of eastern ID/UT into WY and northwest CO. Sufficient instability and modest westerly flow aloft could support a few stronger cells/clusters with strong to locally severe outflow winds. Isolated strong storms will also be possible from eastern CO into western KS, and potentially into the OK/TX Panhandle region. While this area will generally be displaced from stronger large-scale ascent, relatively strong heating, weak to moderate buoyancy, and modest deep-layer flow/shear could support a couple stronger cells/clusters capable of isolated strong/severe gusts and hail. ...Parts of New England... Isolated to widely scattered thunderstorms are possible Wednesday afternoon across parts of New England, along the western periphery of a midlevel low near the Canadian Maritimes. Deep-layer shear will generally be weak, but cold temperatures aloft and unidirectional northerly flow could support a few stronger southward-moving cells/clusters, with small hail and locally gusty winds. Confidence in a more organized severe threat is currently too low for probabilities. ..Dean.. 08/13/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1220 PM CDT Tue Aug 13 2024 Valid 141200Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF EASTERN NE...WESTERN IA...NORTHEAST KS...NORTHWEST MO... ...SUMMARY... Isolated to scattered severe thunderstorms are possible Wednesday across parts of the northern/central Plains into the mid Missouri Valley, with greater potential for large hail, damaging winds, and a tornado or two across parts of northeast Kansas, eastern Nebraska, western Iowa, and northwest Missouri. ...Eastern NE/northeast KS into parts of IA/MO/southern MN... A mid/upper-level trough will move across the central/northern Great Plains towards the upper Midwest on Wednesday. Multiple vorticity maxima, and possibly one or more MCVs, will likely move through the larger-scale trough. The surface pattern will be similarly complex, with a general consensus for a consolidating surface low somewhere across central NE/KS by afternoon. Outflow and cloudiness from morning convection will influence the position of surface boundaries later in the day. One surface boundary that will serve as an effective warm front is forecast to move northward somewhere across northeast KS/northwest MO into eastern NE/western IA, though its position by afternoon/evening remains uncertain. A weak surface trough/cold front will move across parts of the Dakotas into central NE, with another surface trough potentially moving across KS/southeast NE and intersecting the warm front. Given the rather complex surface/upper-air pattern and influence of morning convection, storm evolution remains rather uncertain Wednesday afternoon and evening. From northeast KS/northwest MO into southeast NE/southwest IA, at least isolated storm development will be possible by late afternoon near the warm front and other surface boundaries. Modestly enhanced southwesterly flow aloft will support effective shear of 30-40 kt, and a couple of supercells could evolve from initial development, with a threat of large hail and damaging wind. Some tornado threat would also accompany any supercells near the warm front, especially into the evening when some increase in low-level flow and SRH is expected. With time, one or more upscale-growing clusters may develop, with an attendant threat of damaging gusts spreading eastward across parts of IA/MO. ...Dakotas into central NE... A few strong to locally severe storms will be possible across parts of the Dakotas into central NE. For the Dakotas, somewhat weaker instability and deep-layer shear is expected compared to areas to the south and east, but at least scattered storm development will be possible in conjunction with the mid/upper-level trough. Depending on the extent of heating/destabilization, isolated hail and strong/damaging gusts will be possible. Across central NE, instability and deep-layer shear may be somewhat stronger, though confidence regarding storm coverage decreases with southward extent. A conditional risk for hail and localized severe gusts will accompany any stronger storm in this area. ...Far eastern ID/UT into WY...northern/eastern CO...western KS...TX/OK Panhandles... Another round of relatively high-based convection appears possible Wednesday afternoon into the early evening from parts of eastern ID/UT into WY and northwest CO. Sufficient instability and modest westerly flow aloft could support a few stronger cells/clusters with strong to locally severe outflow winds. Isolated strong storms will also be possible from eastern CO into western KS, and potentially into the OK/TX Panhandle region. While this area will generally be displaced from stronger large-scale ascent, relatively strong heating, weak to moderate buoyancy, and modest deep-layer flow/shear could support a couple stronger cells/clusters capable of isolated strong/severe gusts and hail. ...Parts of New England... Isolated to widely scattered thunderstorms are possible Wednesday afternoon across parts of New England, along the western periphery of a midlevel low near the Canadian Maritimes. Deep-layer shear will generally be weak, but cold temperatures aloft and unidirectional northerly flow could support a few stronger southward-moving cells/clusters, with small hail and locally gusty winds. Confidence in a more organized severe threat is currently too low for probabilities. ..Dean.. 08/13/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1220 PM CDT Tue Aug 13 2024 Valid 141200Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF EASTERN NE...WESTERN IA...NORTHEAST KS...NORTHWEST MO... ...SUMMARY... Isolated to scattered severe thunderstorms are possible Wednesday across parts of the northern/central Plains into the mid Missouri Valley, with greater potential for large hail, damaging winds, and a tornado or two across parts of northeast Kansas, eastern Nebraska, western Iowa, and northwest Missouri. ...Eastern NE/northeast KS into parts of IA/MO/southern MN... A mid/upper-level trough will move across the central/northern Great Plains towards the upper Midwest on Wednesday. Multiple vorticity maxima, and possibly one or more MCVs, will likely move through the larger-scale trough. The surface pattern will be similarly complex, with a general consensus for a consolidating surface low somewhere across central NE/KS by afternoon. Outflow and cloudiness from morning convection will influence the position of surface boundaries later in the day. One surface boundary that will serve as an effective warm front is forecast to move northward somewhere across northeast KS/northwest MO into eastern NE/western IA, though its position by afternoon/evening remains uncertain. A weak surface trough/cold front will move across parts of the Dakotas into central NE, with another surface trough potentially moving across KS/southeast NE and intersecting the warm front. Given the rather complex surface/upper-air pattern and influence of morning convection, storm evolution remains rather uncertain Wednesday afternoon and evening. From northeast KS/northwest MO into southeast NE/southwest IA, at least isolated storm development will be possible by late afternoon near the warm front and other surface boundaries. Modestly enhanced southwesterly flow aloft will support effective shear of 30-40 kt, and a couple of supercells could evolve from initial development, with a threat of large hail and damaging wind. Some tornado threat would also accompany any supercells near the warm front, especially into the evening when some increase in low-level flow and SRH is expected. With time, one or more upscale-growing clusters may develop, with an attendant threat of damaging gusts spreading eastward across parts of IA/MO. ...Dakotas into central NE... A few strong to locally severe storms will be possible across parts of the Dakotas into central NE. For the Dakotas, somewhat weaker instability and deep-layer shear is expected compared to areas to the south and east, but at least scattered storm development will be possible in conjunction with the mid/upper-level trough. Depending on the extent of heating/destabilization, isolated hail and strong/damaging gusts will be possible. Across central NE, instability and deep-layer shear may be somewhat stronger, though confidence regarding storm coverage decreases with southward extent. A conditional risk for hail and localized severe gusts will accompany any stronger storm in this area. ...Far eastern ID/UT into WY...northern/eastern CO...western KS...TX/OK Panhandles... Another round of relatively high-based convection appears possible Wednesday afternoon into the early evening from parts of eastern ID/UT into WY and northwest CO. Sufficient instability and modest westerly flow aloft could support a few stronger cells/clusters with strong to locally severe outflow winds. Isolated strong storms will also be possible from eastern CO into western KS, and potentially into the OK/TX Panhandle region. While this area will generally be displaced from stronger large-scale ascent, relatively strong heating, weak to moderate buoyancy, and modest deep-layer flow/shear could support a couple stronger cells/clusters capable of isolated strong/severe gusts and hail. ...Parts of New England... Isolated to widely scattered thunderstorms are possible Wednesday afternoon across parts of New England, along the western periphery of a midlevel low near the Canadian Maritimes. Deep-layer shear will generally be weak, but cold temperatures aloft and unidirectional northerly flow could support a few stronger southward-moving cells/clusters, with small hail and locally gusty winds. Confidence in a more organized severe threat is currently too low for probabilities. ..Dean.. 08/13/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1220 PM CDT Tue Aug 13 2024 Valid 141200Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF EASTERN NE...WESTERN IA...NORTHEAST KS...NORTHWEST MO... ...SUMMARY... Isolated to scattered severe thunderstorms are possible Wednesday across parts of the northern/central Plains into the mid Missouri Valley, with greater potential for large hail, damaging winds, and a tornado or two across parts of northeast Kansas, eastern Nebraska, western Iowa, and northwest Missouri. ...Eastern NE/northeast KS into parts of IA/MO/southern MN... A mid/upper-level trough will move across the central/northern Great Plains towards the upper Midwest on Wednesday. Multiple vorticity maxima, and possibly one or more MCVs, will likely move through the larger-scale trough. The surface pattern will be similarly complex, with a general consensus for a consolidating surface low somewhere across central NE/KS by afternoon. Outflow and cloudiness from morning convection will influence the position of surface boundaries later in the day. One surface boundary that will serve as an effective warm front is forecast to move northward somewhere across northeast KS/northwest MO into eastern NE/western IA, though its position by afternoon/evening remains uncertain. A weak surface trough/cold front will move across parts of the Dakotas into central NE, with another surface trough potentially moving across KS/southeast NE and intersecting the warm front. Given the rather complex surface/upper-air pattern and influence of morning convection, storm evolution remains rather uncertain Wednesday afternoon and evening. From northeast KS/northwest MO into southeast NE/southwest IA, at least isolated storm development will be possible by late afternoon near the warm front and other surface boundaries. Modestly enhanced southwesterly flow aloft will support effective shear of 30-40 kt, and a couple of supercells could evolve from initial development, with a threat of large hail and damaging wind. Some tornado threat would also accompany any supercells near the warm front, especially into the evening when some increase in low-level flow and SRH is expected. With time, one or more upscale-growing clusters may develop, with an attendant threat of damaging gusts spreading eastward across parts of IA/MO. ...Dakotas into central NE... A few strong to locally severe storms will be possible across parts of the Dakotas into central NE. For the Dakotas, somewhat weaker instability and deep-layer shear is expected compared to areas to the south and east, but at least scattered storm development will be possible in conjunction with the mid/upper-level trough. Depending on the extent of heating/destabilization, isolated hail and strong/damaging gusts will be possible. Across central NE, instability and deep-layer shear may be somewhat stronger, though confidence regarding storm coverage decreases with southward extent. A conditional risk for hail and localized severe gusts will accompany any stronger storm in this area. ...Far eastern ID/UT into WY...northern/eastern CO...western KS...TX/OK Panhandles... Another round of relatively high-based convection appears possible Wednesday afternoon into the early evening from parts of eastern ID/UT into WY and northwest CO. Sufficient instability and modest westerly flow aloft could support a few stronger cells/clusters with strong to locally severe outflow winds. Isolated strong storms will also be possible from eastern CO into western KS, and potentially into the OK/TX Panhandle region. While this area will generally be displaced from stronger large-scale ascent, relatively strong heating, weak to moderate buoyancy, and modest deep-layer flow/shear could support a couple stronger cells/clusters capable of isolated strong/severe gusts and hail. ...Parts of New England... Isolated to widely scattered thunderstorms are possible Wednesday afternoon across parts of New England, along the western periphery of a midlevel low near the Canadian Maritimes. Deep-layer shear will generally be weak, but cold temperatures aloft and unidirectional northerly flow could support a few stronger southward-moving cells/clusters, with small hail and locally gusty winds. Confidence in a more organized severe threat is currently too low for probabilities. ..Dean.. 08/13/2024 Read more

No Mesoscale Discussions are in effect as of Tue Aug 13 17:25:02 UTC 2024.

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1126 AM CDT Tue Aug 13 2024 Valid 131630Z - 141200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM NORTHEAST CO INTO SOUTHWEST NE AND FAR NORTHWEST KS... ...SUMMARY... Severe thunderstorms are possible this afternoon and evening from northeast Colorado into southwest Nebraska and far northwest Kansas. Strong to isolated severe thunderstorms are also possible this afternoon and evening across parts of the eastern Great Basin/northern Intermountain region into the northern/central High Plains and central Great Plains, as well as South Carolina. ...Central High Plains into the Central Plains... Low-amplitude shortwave trough currently moving through the Four Corners vicinity is expected to continue northeastward, helping to support afternoon thunderstorms across the central Rockies. Favorable low-level moisture will exist within the airmass downstream across the central High Plains, characterized by late afternoon dewpoints in the low to mid 60s. Ongoing cloud covered may delay heating a bit, but temperatures are still expected to reach the mid 80s by the late afternoon. These low-level thermodynamic conditions will help remove convective inhibition while also supporting moderate buoyancy. The westerly/southwesterly flow aloft should remain relatively modest (i.e. 20 to 30 kt at 500 mb), but the veering wind profiles expected to be in place will still result in moderate vertical shear. Current expectation is for 0-6 km bulk shear to range from 25 to 35 kt, with the highest values located over northeast CO into western NE. A predominantly multicellular mode is anticipated, with isolated large hail and a damaging gusts possible. The stronger shear over northeast CO suggests a more organized mode is possible here, with the development of a forward-propagating convective line anticipated. Strong gusts will be possible within this line. This line may continue eastward into the central Plains overnight, supported by a moderate low-level jet. ...Lower MO Valley into southeast NE... Ongoing convective complex moving through southwest MO is expected to continue southeastward while gradually weakening. Some re-development is possible during the evening, beginning across southwest MO, as warm-air advection occurs along the remnant outflow. Thunderstorm development should then expand northwestward into northeast KS, northwest MO, and southeast NE as the low-level jet continues to strengthen. Some isolated hail is possible within the strongest storms. Additionally, despite their elevated character, downdrafts could become strong enough to penetrate any low-level stability, with some damaging gusts possible. ...Intermountain West into the northern High Plains... Early-day satellite imagery shows upper ridging centered over the southern Plains and upper troughing from Pacific Northwest into central CA. Moderately enhanced southwesterly flow aloft is in place between these two features, from the Great Basin across much of the Intermountain West and into the northern High Plains. A shortwave trough currently moving through the western Great Basin is expected to progress through this southwesterly flow, reaching the northern High Plains by early Wednesday morning. Favorable moisture is in place ahead of this wave, as evidence by PWATs around 1" sampled by the 12Z soundings at SLC and GJT, with near 0.9" at BOI as well. Scattered to numerous thunderstorms are expected across the region, as northeastward-progressing shortwave trough interacts with this favorable moisture. Ongoing cloud cover and filtered daytime heating is expected to keep temperatures in the upper 70s across much of the region, with slightly warmer temperatures possible across eastern ID and northeastern UT. These temperatures combined with the mid-level moisture already in place will support moderate buoyancy, with the enhanced mid-level flow supporting moderate vertical shear as well. As a result, a largely multicellular mode is anticipated, but a few more organized storms are possible, with occasional bowing segments capable of producing strong gusts. The only exception is across the eastern ID/northeast UT vicinity, where slightly better buoyancy and shear could result in a few supercells. Anticipated isolated coverage currently precludes the need for higher severe probabilities. ...South Carolina... A weak surface low is near the southern SC coast this morning. Modest low-level convergence from this low northwestward into western SC/northeast GA is helping support showers and occasional thunderstorms. This convergence will likely persist throughout the day, with the showers and thunderstorms progressing gradually eastward. A very moist airmass is in place, as evidenced by 16.7 g/kg lowest 100-mb mean mixing ratio on the 12Z CHS sounding, and will diurnally destabilize today. Moderate west-northwesterlies (around 30 kt at 500 mb) may aid in some multicellular organization. Isolated gusts 50-60 mph capable of wind damage will be the primary concern with the stronger storms. ..Mosier/Weinman.. 08/13/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1126 AM CDT Tue Aug 13 2024 Valid 131630Z - 141200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM NORTHEAST CO INTO SOUTHWEST NE AND FAR NORTHWEST KS... ...SUMMARY... Severe thunderstorms are possible this afternoon and evening from northeast Colorado into southwest Nebraska and far northwest Kansas. Strong to isolated severe thunderstorms are also possible this afternoon and evening across parts of the eastern Great Basin/northern Intermountain region into the northern/central High Plains and central Great Plains, as well as South Carolina. ...Central High Plains into the Central Plains... Low-amplitude shortwave trough currently moving through the Four Corners vicinity is expected to continue northeastward, helping to support afternoon thunderstorms across the central Rockies. Favorable low-level moisture will exist within the airmass downstream across the central High Plains, characterized by late afternoon dewpoints in the low to mid 60s. Ongoing cloud covered may delay heating a bit, but temperatures are still expected to reach the mid 80s by the late afternoon. These low-level thermodynamic conditions will help remove convective inhibition while also supporting moderate buoyancy. The westerly/southwesterly flow aloft should remain relatively modest (i.e. 20 to 30 kt at 500 mb), but the veering wind profiles expected to be in place will still result in moderate vertical shear. Current expectation is for 0-6 km bulk shear to range from 25 to 35 kt, with the highest values located over northeast CO into western NE. A predominantly multicellular mode is anticipated, with isolated large hail and a damaging gusts possible. The stronger shear over northeast CO suggests a more organized mode is possible here, with the development of a forward-propagating convective line anticipated. Strong gusts will be possible within this line. This line may continue eastward into the central Plains overnight, supported by a moderate low-level jet. ...Lower MO Valley into southeast NE... Ongoing convective complex moving through southwest MO is expected to continue southeastward while gradually weakening. Some re-development is possible during the evening, beginning across southwest MO, as warm-air advection occurs along the remnant outflow. Thunderstorm development should then expand northwestward into northeast KS, northwest MO, and southeast NE as the low-level jet continues to strengthen. Some isolated hail is possible within the strongest storms. Additionally, despite their elevated character, downdrafts could become strong enough to penetrate any low-level stability, with some damaging gusts possible. ...Intermountain West into the northern High Plains... Early-day satellite imagery shows upper ridging centered over the southern Plains and upper troughing from Pacific Northwest into central CA. Moderately enhanced southwesterly flow aloft is in place between these two features, from the Great Basin across much of the Intermountain West and into the northern High Plains. A shortwave trough currently moving through the western Great Basin is expected to progress through this southwesterly flow, reaching the northern High Plains by early Wednesday morning. Favorable moisture is in place ahead of this wave, as evidence by PWATs around 1" sampled by the 12Z soundings at SLC and GJT, with near 0.9" at BOI as well. Scattered to numerous thunderstorms are expected across the region, as northeastward-progressing shortwave trough interacts with this favorable moisture. Ongoing cloud cover and filtered daytime heating is expected to keep temperatures in the upper 70s across much of the region, with slightly warmer temperatures possible across eastern ID and northeastern UT. These temperatures combined with the mid-level moisture already in place will support moderate buoyancy, with the enhanced mid-level flow supporting moderate vertical shear as well. As a result, a largely multicellular mode is anticipated, but a few more organized storms are possible, with occasional bowing segments capable of producing strong gusts. The only exception is across the eastern ID/northeast UT vicinity, where slightly better buoyancy and shear could result in a few supercells. Anticipated isolated coverage currently precludes the need for higher severe probabilities. ...South Carolina... A weak surface low is near the southern SC coast this morning. Modest low-level convergence from this low northwestward into western SC/northeast GA is helping support showers and occasional thunderstorms. This convergence will likely persist throughout the day, with the showers and thunderstorms progressing gradually eastward. A very moist airmass is in place, as evidenced by 16.7 g/kg lowest 100-mb mean mixing ratio on the 12Z CHS sounding, and will diurnally destabilize today. Moderate west-northwesterlies (around 30 kt at 500 mb) may aid in some multicellular organization. Isolated gusts 50-60 mph capable of wind damage will be the primary concern with the stronger storms. ..Mosier/Weinman.. 08/13/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1126 AM CDT Tue Aug 13 2024 Valid 131630Z - 141200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM NORTHEAST CO INTO SOUTHWEST NE AND FAR NORTHWEST KS... ...SUMMARY... Severe thunderstorms are possible this afternoon and evening from northeast Colorado into southwest Nebraska and far northwest Kansas. Strong to isolated severe thunderstorms are also possible this afternoon and evening across parts of the eastern Great Basin/northern Intermountain region into the northern/central High Plains and central Great Plains, as well as South Carolina. ...Central High Plains into the Central Plains... Low-amplitude shortwave trough currently moving through the Four Corners vicinity is expected to continue northeastward, helping to support afternoon thunderstorms across the central Rockies. Favorable low-level moisture will exist within the airmass downstream across the central High Plains, characterized by late afternoon dewpoints in the low to mid 60s. Ongoing cloud covered may delay heating a bit, but temperatures are still expected to reach the mid 80s by the late afternoon. These low-level thermodynamic conditions will help remove convective inhibition while also supporting moderate buoyancy. The westerly/southwesterly flow aloft should remain relatively modest (i.e. 20 to 30 kt at 500 mb), but the veering wind profiles expected to be in place will still result in moderate vertical shear. Current expectation is for 0-6 km bulk shear to range from 25 to 35 kt, with the highest values located over northeast CO into western NE. A predominantly multicellular mode is anticipated, with isolated large hail and a damaging gusts possible. The stronger shear over northeast CO suggests a more organized mode is possible here, with the development of a forward-propagating convective line anticipated. Strong gusts will be possible within this line. This line may continue eastward into the central Plains overnight, supported by a moderate low-level jet. ...Lower MO Valley into southeast NE... Ongoing convective complex moving through southwest MO is expected to continue southeastward while gradually weakening. Some re-development is possible during the evening, beginning across southwest MO, as warm-air advection occurs along the remnant outflow. Thunderstorm development should then expand northwestward into northeast KS, northwest MO, and southeast NE as the low-level jet continues to strengthen. Some isolated hail is possible within the strongest storms. Additionally, despite their elevated character, downdrafts could become strong enough to penetrate any low-level stability, with some damaging gusts possible. ...Intermountain West into the northern High Plains... Early-day satellite imagery shows upper ridging centered over the southern Plains and upper troughing from Pacific Northwest into central CA. Moderately enhanced southwesterly flow aloft is in place between these two features, from the Great Basin across much of the Intermountain West and into the northern High Plains. A shortwave trough currently moving through the western Great Basin is expected to progress through this southwesterly flow, reaching the northern High Plains by early Wednesday morning. Favorable moisture is in place ahead of this wave, as evidence by PWATs around 1" sampled by the 12Z soundings at SLC and GJT, with near 0.9" at BOI as well. Scattered to numerous thunderstorms are expected across the region, as northeastward-progressing shortwave trough interacts with this favorable moisture. Ongoing cloud cover and filtered daytime heating is expected to keep temperatures in the upper 70s across much of the region, with slightly warmer temperatures possible across eastern ID and northeastern UT. These temperatures combined with the mid-level moisture already in place will support moderate buoyancy, with the enhanced mid-level flow supporting moderate vertical shear as well. As a result, a largely multicellular mode is anticipated, but a few more organized storms are possible, with occasional bowing segments capable of producing strong gusts. The only exception is across the eastern ID/northeast UT vicinity, where slightly better buoyancy and shear could result in a few supercells. Anticipated isolated coverage currently precludes the need for higher severe probabilities. ...South Carolina... A weak surface low is near the southern SC coast this morning. Modest low-level convergence from this low northwestward into western SC/northeast GA is helping support showers and occasional thunderstorms. This convergence will likely persist throughout the day, with the showers and thunderstorms progressing gradually eastward. A very moist airmass is in place, as evidenced by 16.7 g/kg lowest 100-mb mean mixing ratio on the 12Z CHS sounding, and will diurnally destabilize today. Moderate west-northwesterlies (around 30 kt at 500 mb) may aid in some multicellular organization. Isolated gusts 50-60 mph capable of wind damage will be the primary concern with the stronger storms. ..Mosier/Weinman.. 08/13/2024 Read more