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SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0137 PM CDT Thu May 16 2024 Valid 171200Z - 181200Z ...NO CRITICAL AREAS... ...2000Z Update... A surface low will deepen in the lee of the northern Rockies over the High Plains of southeast Montana and northeast Wyoming Friday in association with an approaching mid-level trough. The resulting pressure gradient will support breezy westerly sustained surface winds around 20 to 30 mph from central Montana into Idaho and southwest Wyoming. There's still some disagreement on how low RH will drop across northeast Idaho and far western/southwestern Wyoming, as mentioned in the previous forecast. Regardless, recent rainfall over this region and relatively low fuel receptiveness will limit the overall fire spread threat. ..Barnes/Nauslar.. 05/16/2024 .PREV DISCUSSION... /ISSUED 0122 AM CDT Thu May 16 2024/ ...Synopsis... A pronounced mid-level trough will eject into the northern Plains today, supporting strong surface lee troughing over the northern High Plains tomorrow (Friday). A widespread, strong surface wind field will develop over Wyoming and points eastward as a result. However, guidance varies considerably in terms of how low RH will drop by afternoon peak heating, with some guidance members showing RH dropping as low as 15 percent in some spots, while other members show RH staying well above 25 percent in many locales. When also considering recent rainfall that portions of the northern Plains has received in the past week, fuel receptiveness to wildfire spread should also be mediocre. Fire weather highlights have been withheld given the aforementioned uncertainties with RH and fuels. Nonetheless, localized instances of wildfire growth cannot be ruled out where dry fuel beds exist given the strong winds. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

No Mesoscale Discussions are in effect as of Thu May 16 18:00:15 UTC 2024.

000
ABPZ20 KNHC 161746
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 AM PDT Thu May 16 2024

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

South of the Coast of Southwestern Mexico:
Satellite data indicate that a small area of low pressure located
several hundred miles offshore of the coast of southwestern Mexico
is producing some disorganized showers and thunderstorms. Some
gradual development is possible during the next day or so while the
low moves little. By this weekend, the system is forecast to merge
with another disturbance to its east.
* Formation chance through 48 hours...low...20 percent.
* Formation chance through 7 days...low...20 percent.

South of the Coast of Southern Mexico:
An area of low pressure is forecast to form several hundred miles to
the south of southern Mexico during the next couple of days. Gradual
development is possible thereafter, and a tropical depression could
form over the weekend or early next week while the system moves
slowly to the west or west-northwest, remaining south of the coast
of Mexico.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...medium...40 percent.

$$
Forecaster Hagen/Reinhart

MD 0801 CONCERNING SEVERE POTENTIAL...WATCH LIKELY FOR PARTS OF CENTRAL TEXAS
Mesoscale Discussion 0801 NWS Storm Prediction Center Norman OK 1026 AM CDT Thu May 16 2024 Areas affected...parts of central Texas Concerning...Severe potential...Watch likely Valid 161526Z - 161800Z Probability of Watch Issuance...80 percent SUMMARY...Storms will likely increase in coverage and intensity over the next several hours, with damaging wind and areas of hail. DISCUSSION...Widespread rain and storms currently exist along and north of an outflow boundary, extending from just south of the MAF to SJT area and curling into northeastern TX. Surface observations indicate the outflow continues to push south, resulting in an undercutting action to the existing convection. As of 15Z, the most notable area of storms was just northeast of SJT. This convection may be developing into a small MCS, with northern portions clearly elevated and additional development occurring along the southern flank. These storms may continue to grow upscale, ingesting the very moist and unstable air, and translating east/southeast along the cold front/outflow. Additional storms are also developing just southwest of SJT, where robust moisture has pushed westward beneath slightly cooler temperatures aloft with less capping. The deepening boundary layer should generally reduce CIN through the day, with the end result increasing coverage of strong to severe storms. Damaging winds will be the primary threat, although large hail may occur with the more discrete storms before they merge into an MCS. ..Jewell/Thompson.. 05/16/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...FWD...EWX...SJT... LAT...LON 30139882 30140099 30300133 30610140 30970127 31110115 31400087 31769972 31879902 32109770 32239695 31949646 31469627 31069646 30769679 30669697 30469745 30139882 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1226 PM CDT Thu May 16 2024 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN PARTS OF THE GULF COAST STATES... ...SUMMARY... Scattered severe thunderstorms with a few tornadoes, very large hail, and damaging winds are possible across parts of the Gulf Coast States on Friday through Friday night. ...South-central to Southeast States... A messy severe weather setup is expected on Friday into Friday night amid a series of low-amplitude impulses ejecting within and around the positive-tilt, southern-stream shortwave trough across the southern Great Plains. Synoptic surface pattern appears nebulous and likely driven on the mesoscale by several rounds of convection today through the end of D2. Primary changes with this outlook are to expand severe probabilities west and east, while reducing probabilities across the northern portion of the threat area. An MCS or clustered remnants of an early morning one should be ongoing at 12Z Friday across parts of the central Gulf Coast region. Outflow from this preceding D1 activity will serve as the focus for renewed thunderstorm development later in the day. Most guidance suggests a separate area of upstream convection may be ongoing or will develop by midday across parts of south TX and the TX Gulf Coast along and behind the composite outflow/cold front that will surge southeast in TX on D1. With the fastest mid-level southwesterlies expected to overlie the western to central Gulf Coast during the first half of the period, supercells capable of very large hail will be possible. This threat should be focused in a narrow corridor along the TX Gulf Coast initially, and then develop later in the afternoon to evening in the central Gulf Coast. Some of this latter activity will have relatively greater potential for tornado/wind threats, focused along the outflow in the wake of the early-morning MCS. Additional isolated to scattered thunderstorm development should occur within the post-frontal/outflow air mass centered on parts of the Red River Valley and in south-central TX near the Rio Grande. This activity will likely be aided by the embedded low-amplitude impulses within the southern-stream shortwave trough. Residual buoyancy should be adequate for an isolated hail/wind threat amid more muted deep-layer shear closer to the trough axis. ...Northern Great Plains... A vigorous, northern-stream shortwave trough will move across the northern Rockies into the Prairie Provinces and adjacent parts of MT/ND through early Saturday. Primary surface cyclone will occlude over SK/MB, with secondary cyclogenesis occurring near the SD/WY/MT border area along the trailing Pacific cold front. With only modified moisture return ahead of the front, MLCAPE will remain rather weak. Initial convective development will probably occur within the post-frontal upslope flow regime during the early to mid afternoon. This activity should spread east and likely expand during the late afternoon into the evening. With deeply mixed thermodynamic profiles ahead of the front, and steep lapse rates being maintained behind it, high-based thunderstorms with amalgamating outflows are expected. While the bulk of strong 700-500 mb westerlies will lag behind the front, the strengthening flow should support a threat for strong to isolated severe surface gusts before convection wanes after dusk. ..Grams.. 05/16/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1226 PM CDT Thu May 16 2024 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN PARTS OF THE GULF COAST STATES... ...SUMMARY... Scattered severe thunderstorms with a few tornadoes, very large hail, and damaging winds are possible across parts of the Gulf Coast States on Friday through Friday night. ...South-central to Southeast States... A messy severe weather setup is expected on Friday into Friday night amid a series of low-amplitude impulses ejecting within and around the positive-tilt, southern-stream shortwave trough across the southern Great Plains. Synoptic surface pattern appears nebulous and likely driven on the mesoscale by several rounds of convection today through the end of D2. Primary changes with this outlook are to expand severe probabilities west and east, while reducing probabilities across the northern portion of the threat area. An MCS or clustered remnants of an early morning one should be ongoing at 12Z Friday across parts of the central Gulf Coast region. Outflow from this preceding D1 activity will serve as the focus for renewed thunderstorm development later in the day. Most guidance suggests a separate area of upstream convection may be ongoing or will develop by midday across parts of south TX and the TX Gulf Coast along and behind the composite outflow/cold front that will surge southeast in TX on D1. With the fastest mid-level southwesterlies expected to overlie the western to central Gulf Coast during the first half of the period, supercells capable of very large hail will be possible. This threat should be focused in a narrow corridor along the TX Gulf Coast initially, and then develop later in the afternoon to evening in the central Gulf Coast. Some of this latter activity will have relatively greater potential for tornado/wind threats, focused along the outflow in the wake of the early-morning MCS. Additional isolated to scattered thunderstorm development should occur within the post-frontal/outflow air mass centered on parts of the Red River Valley and in south-central TX near the Rio Grande. This activity will likely be aided by the embedded low-amplitude impulses within the southern-stream shortwave trough. Residual buoyancy should be adequate for an isolated hail/wind threat amid more muted deep-layer shear closer to the trough axis. ...Northern Great Plains... A vigorous, northern-stream shortwave trough will move across the northern Rockies into the Prairie Provinces and adjacent parts of MT/ND through early Saturday. Primary surface cyclone will occlude over SK/MB, with secondary cyclogenesis occurring near the SD/WY/MT border area along the trailing Pacific cold front. With only modified moisture return ahead of the front, MLCAPE will remain rather weak. Initial convective development will probably occur within the post-frontal upslope flow regime during the early to mid afternoon. This activity should spread east and likely expand during the late afternoon into the evening. With deeply mixed thermodynamic profiles ahead of the front, and steep lapse rates being maintained behind it, high-based thunderstorms with amalgamating outflows are expected. While the bulk of strong 700-500 mb westerlies will lag behind the front, the strengthening flow should support a threat for strong to isolated severe surface gusts before convection wanes after dusk. ..Grams.. 05/16/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1226 PM CDT Thu May 16 2024 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN PARTS OF THE GULF COAST STATES... ...SUMMARY... Scattered severe thunderstorms with a few tornadoes, very large hail, and damaging winds are possible across parts of the Gulf Coast States on Friday through Friday night. ...South-central to Southeast States... A messy severe weather setup is expected on Friday into Friday night amid a series of low-amplitude impulses ejecting within and around the positive-tilt, southern-stream shortwave trough across the southern Great Plains. Synoptic surface pattern appears nebulous and likely driven on the mesoscale by several rounds of convection today through the end of D2. Primary changes with this outlook are to expand severe probabilities west and east, while reducing probabilities across the northern portion of the threat area. An MCS or clustered remnants of an early morning one should be ongoing at 12Z Friday across parts of the central Gulf Coast region. Outflow from this preceding D1 activity will serve as the focus for renewed thunderstorm development later in the day. Most guidance suggests a separate area of upstream convection may be ongoing or will develop by midday across parts of south TX and the TX Gulf Coast along and behind the composite outflow/cold front that will surge southeast in TX on D1. With the fastest mid-level southwesterlies expected to overlie the western to central Gulf Coast during the first half of the period, supercells capable of very large hail will be possible. This threat should be focused in a narrow corridor along the TX Gulf Coast initially, and then develop later in the afternoon to evening in the central Gulf Coast. Some of this latter activity will have relatively greater potential for tornado/wind threats, focused along the outflow in the wake of the early-morning MCS. Additional isolated to scattered thunderstorm development should occur within the post-frontal/outflow air mass centered on parts of the Red River Valley and in south-central TX near the Rio Grande. This activity will likely be aided by the embedded low-amplitude impulses within the southern-stream shortwave trough. Residual buoyancy should be adequate for an isolated hail/wind threat amid more muted deep-layer shear closer to the trough axis. ...Northern Great Plains... A vigorous, northern-stream shortwave trough will move across the northern Rockies into the Prairie Provinces and adjacent parts of MT/ND through early Saturday. Primary surface cyclone will occlude over SK/MB, with secondary cyclogenesis occurring near the SD/WY/MT border area along the trailing Pacific cold front. With only modified moisture return ahead of the front, MLCAPE will remain rather weak. Initial convective development will probably occur within the post-frontal upslope flow regime during the early to mid afternoon. This activity should spread east and likely expand during the late afternoon into the evening. With deeply mixed thermodynamic profiles ahead of the front, and steep lapse rates being maintained behind it, high-based thunderstorms with amalgamating outflows are expected. While the bulk of strong 700-500 mb westerlies will lag behind the front, the strengthening flow should support a threat for strong to isolated severe surface gusts before convection wanes after dusk. ..Grams.. 05/16/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1226 PM CDT Thu May 16 2024 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN PARTS OF THE GULF COAST STATES... ...SUMMARY... Scattered severe thunderstorms with a few tornadoes, very large hail, and damaging winds are possible across parts of the Gulf Coast States on Friday through Friday night. ...South-central to Southeast States... A messy severe weather setup is expected on Friday into Friday night amid a series of low-amplitude impulses ejecting within and around the positive-tilt, southern-stream shortwave trough across the southern Great Plains. Synoptic surface pattern appears nebulous and likely driven on the mesoscale by several rounds of convection today through the end of D2. Primary changes with this outlook are to expand severe probabilities west and east, while reducing probabilities across the northern portion of the threat area. An MCS or clustered remnants of an early morning one should be ongoing at 12Z Friday across parts of the central Gulf Coast region. Outflow from this preceding D1 activity will serve as the focus for renewed thunderstorm development later in the day. Most guidance suggests a separate area of upstream convection may be ongoing or will develop by midday across parts of south TX and the TX Gulf Coast along and behind the composite outflow/cold front that will surge southeast in TX on D1. With the fastest mid-level southwesterlies expected to overlie the western to central Gulf Coast during the first half of the period, supercells capable of very large hail will be possible. This threat should be focused in a narrow corridor along the TX Gulf Coast initially, and then develop later in the afternoon to evening in the central Gulf Coast. Some of this latter activity will have relatively greater potential for tornado/wind threats, focused along the outflow in the wake of the early-morning MCS. Additional isolated to scattered thunderstorm development should occur within the post-frontal/outflow air mass centered on parts of the Red River Valley and in south-central TX near the Rio Grande. This activity will likely be aided by the embedded low-amplitude impulses within the southern-stream shortwave trough. Residual buoyancy should be adequate for an isolated hail/wind threat amid more muted deep-layer shear closer to the trough axis. ...Northern Great Plains... A vigorous, northern-stream shortwave trough will move across the northern Rockies into the Prairie Provinces and adjacent parts of MT/ND through early Saturday. Primary surface cyclone will occlude over SK/MB, with secondary cyclogenesis occurring near the SD/WY/MT border area along the trailing Pacific cold front. With only modified moisture return ahead of the front, MLCAPE will remain rather weak. Initial convective development will probably occur within the post-frontal upslope flow regime during the early to mid afternoon. This activity should spread east and likely expand during the late afternoon into the evening. With deeply mixed thermodynamic profiles ahead of the front, and steep lapse rates being maintained behind it, high-based thunderstorms with amalgamating outflows are expected. While the bulk of strong 700-500 mb westerlies will lag behind the front, the strengthening flow should support a threat for strong to isolated severe surface gusts before convection wanes after dusk. ..Grams.. 05/16/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1226 PM CDT Thu May 16 2024 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN PARTS OF THE GULF COAST STATES... ...SUMMARY... Scattered severe thunderstorms with a few tornadoes, very large hail, and damaging winds are possible across parts of the Gulf Coast States on Friday through Friday night. ...South-central to Southeast States... A messy severe weather setup is expected on Friday into Friday night amid a series of low-amplitude impulses ejecting within and around the positive-tilt, southern-stream shortwave trough across the southern Great Plains. Synoptic surface pattern appears nebulous and likely driven on the mesoscale by several rounds of convection today through the end of D2. Primary changes with this outlook are to expand severe probabilities west and east, while reducing probabilities across the northern portion of the threat area. An MCS or clustered remnants of an early morning one should be ongoing at 12Z Friday across parts of the central Gulf Coast region. Outflow from this preceding D1 activity will serve as the focus for renewed thunderstorm development later in the day. Most guidance suggests a separate area of upstream convection may be ongoing or will develop by midday across parts of south TX and the TX Gulf Coast along and behind the composite outflow/cold front that will surge southeast in TX on D1. With the fastest mid-level southwesterlies expected to overlie the western to central Gulf Coast during the first half of the period, supercells capable of very large hail will be possible. This threat should be focused in a narrow corridor along the TX Gulf Coast initially, and then develop later in the afternoon to evening in the central Gulf Coast. Some of this latter activity will have relatively greater potential for tornado/wind threats, focused along the outflow in the wake of the early-morning MCS. Additional isolated to scattered thunderstorm development should occur within the post-frontal/outflow air mass centered on parts of the Red River Valley and in south-central TX near the Rio Grande. This activity will likely be aided by the embedded low-amplitude impulses within the southern-stream shortwave trough. Residual buoyancy should be adequate for an isolated hail/wind threat amid more muted deep-layer shear closer to the trough axis. ...Northern Great Plains... A vigorous, northern-stream shortwave trough will move across the northern Rockies into the Prairie Provinces and adjacent parts of MT/ND through early Saturday. Primary surface cyclone will occlude over SK/MB, with secondary cyclogenesis occurring near the SD/WY/MT border area along the trailing Pacific cold front. With only modified moisture return ahead of the front, MLCAPE will remain rather weak. Initial convective development will probably occur within the post-frontal upslope flow regime during the early to mid afternoon. This activity should spread east and likely expand during the late afternoon into the evening. With deeply mixed thermodynamic profiles ahead of the front, and steep lapse rates being maintained behind it, high-based thunderstorms with amalgamating outflows are expected. While the bulk of strong 700-500 mb westerlies will lag behind the front, the strengthening flow should support a threat for strong to isolated severe surface gusts before convection wanes after dusk. ..Grams.. 05/16/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1226 PM CDT Thu May 16 2024 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN PARTS OF THE GULF COAST STATES... ...SUMMARY... Scattered severe thunderstorms with a few tornadoes, very large hail, and damaging winds are possible across parts of the Gulf Coast States on Friday through Friday night. ...South-central to Southeast States... A messy severe weather setup is expected on Friday into Friday night amid a series of low-amplitude impulses ejecting within and around the positive-tilt, southern-stream shortwave trough across the southern Great Plains. Synoptic surface pattern appears nebulous and likely driven on the mesoscale by several rounds of convection today through the end of D2. Primary changes with this outlook are to expand severe probabilities west and east, while reducing probabilities across the northern portion of the threat area. An MCS or clustered remnants of an early morning one should be ongoing at 12Z Friday across parts of the central Gulf Coast region. Outflow from this preceding D1 activity will serve as the focus for renewed thunderstorm development later in the day. Most guidance suggests a separate area of upstream convection may be ongoing or will develop by midday across parts of south TX and the TX Gulf Coast along and behind the composite outflow/cold front that will surge southeast in TX on D1. With the fastest mid-level southwesterlies expected to overlie the western to central Gulf Coast during the first half of the period, supercells capable of very large hail will be possible. This threat should be focused in a narrow corridor along the TX Gulf Coast initially, and then develop later in the afternoon to evening in the central Gulf Coast. Some of this latter activity will have relatively greater potential for tornado/wind threats, focused along the outflow in the wake of the early-morning MCS. Additional isolated to scattered thunderstorm development should occur within the post-frontal/outflow air mass centered on parts of the Red River Valley and in south-central TX near the Rio Grande. This activity will likely be aided by the embedded low-amplitude impulses within the southern-stream shortwave trough. Residual buoyancy should be adequate for an isolated hail/wind threat amid more muted deep-layer shear closer to the trough axis. ...Northern Great Plains... A vigorous, northern-stream shortwave trough will move across the northern Rockies into the Prairie Provinces and adjacent parts of MT/ND through early Saturday. Primary surface cyclone will occlude over SK/MB, with secondary cyclogenesis occurring near the SD/WY/MT border area along the trailing Pacific cold front. With only modified moisture return ahead of the front, MLCAPE will remain rather weak. Initial convective development will probably occur within the post-frontal upslope flow regime during the early to mid afternoon. This activity should spread east and likely expand during the late afternoon into the evening. With deeply mixed thermodynamic profiles ahead of the front, and steep lapse rates being maintained behind it, high-based thunderstorms with amalgamating outflows are expected. While the bulk of strong 700-500 mb westerlies will lag behind the front, the strengthening flow should support a threat for strong to isolated severe surface gusts before convection wanes after dusk. ..Grams.. 05/16/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1226 PM CDT Thu May 16 2024 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN PARTS OF THE GULF COAST STATES... ...SUMMARY... Scattered severe thunderstorms with a few tornadoes, very large hail, and damaging winds are possible across parts of the Gulf Coast States on Friday through Friday night. ...South-central to Southeast States... A messy severe weather setup is expected on Friday into Friday night amid a series of low-amplitude impulses ejecting within and around the positive-tilt, southern-stream shortwave trough across the southern Great Plains. Synoptic surface pattern appears nebulous and likely driven on the mesoscale by several rounds of convection today through the end of D2. Primary changes with this outlook are to expand severe probabilities west and east, while reducing probabilities across the northern portion of the threat area. An MCS or clustered remnants of an early morning one should be ongoing at 12Z Friday across parts of the central Gulf Coast region. Outflow from this preceding D1 activity will serve as the focus for renewed thunderstorm development later in the day. Most guidance suggests a separate area of upstream convection may be ongoing or will develop by midday across parts of south TX and the TX Gulf Coast along and behind the composite outflow/cold front that will surge southeast in TX on D1. With the fastest mid-level southwesterlies expected to overlie the western to central Gulf Coast during the first half of the period, supercells capable of very large hail will be possible. This threat should be focused in a narrow corridor along the TX Gulf Coast initially, and then develop later in the afternoon to evening in the central Gulf Coast. Some of this latter activity will have relatively greater potential for tornado/wind threats, focused along the outflow in the wake of the early-morning MCS. Additional isolated to scattered thunderstorm development should occur within the post-frontal/outflow air mass centered on parts of the Red River Valley and in south-central TX near the Rio Grande. This activity will likely be aided by the embedded low-amplitude impulses within the southern-stream shortwave trough. Residual buoyancy should be adequate for an isolated hail/wind threat amid more muted deep-layer shear closer to the trough axis. ...Northern Great Plains... A vigorous, northern-stream shortwave trough will move across the northern Rockies into the Prairie Provinces and adjacent parts of MT/ND through early Saturday. Primary surface cyclone will occlude over SK/MB, with secondary cyclogenesis occurring near the SD/WY/MT border area along the trailing Pacific cold front. With only modified moisture return ahead of the front, MLCAPE will remain rather weak. Initial convective development will probably occur within the post-frontal upslope flow regime during the early to mid afternoon. This activity should spread east and likely expand during the late afternoon into the evening. With deeply mixed thermodynamic profiles ahead of the front, and steep lapse rates being maintained behind it, high-based thunderstorms with amalgamating outflows are expected. While the bulk of strong 700-500 mb westerlies will lag behind the front, the strengthening flow should support a threat for strong to isolated severe surface gusts before convection wanes after dusk. ..Grams.. 05/16/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1226 PM CDT Thu May 16 2024 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN PARTS OF THE GULF COAST STATES... ...SUMMARY... Scattered severe thunderstorms with a few tornadoes, very large hail, and damaging winds are possible across parts of the Gulf Coast States on Friday through Friday night. ...South-central to Southeast States... A messy severe weather setup is expected on Friday into Friday night amid a series of low-amplitude impulses ejecting within and around the positive-tilt, southern-stream shortwave trough across the southern Great Plains. Synoptic surface pattern appears nebulous and likely driven on the mesoscale by several rounds of convection today through the end of D2. Primary changes with this outlook are to expand severe probabilities west and east, while reducing probabilities across the northern portion of the threat area. An MCS or clustered remnants of an early morning one should be ongoing at 12Z Friday across parts of the central Gulf Coast region. Outflow from this preceding D1 activity will serve as the focus for renewed thunderstorm development later in the day. Most guidance suggests a separate area of upstream convection may be ongoing or will develop by midday across parts of south TX and the TX Gulf Coast along and behind the composite outflow/cold front that will surge southeast in TX on D1. With the fastest mid-level southwesterlies expected to overlie the western to central Gulf Coast during the first half of the period, supercells capable of very large hail will be possible. This threat should be focused in a narrow corridor along the TX Gulf Coast initially, and then develop later in the afternoon to evening in the central Gulf Coast. Some of this latter activity will have relatively greater potential for tornado/wind threats, focused along the outflow in the wake of the early-morning MCS. Additional isolated to scattered thunderstorm development should occur within the post-frontal/outflow air mass centered on parts of the Red River Valley and in south-central TX near the Rio Grande. This activity will likely be aided by the embedded low-amplitude impulses within the southern-stream shortwave trough. Residual buoyancy should be adequate for an isolated hail/wind threat amid more muted deep-layer shear closer to the trough axis. ...Northern Great Plains... A vigorous, northern-stream shortwave trough will move across the northern Rockies into the Prairie Provinces and adjacent parts of MT/ND through early Saturday. Primary surface cyclone will occlude over SK/MB, with secondary cyclogenesis occurring near the SD/WY/MT border area along the trailing Pacific cold front. With only modified moisture return ahead of the front, MLCAPE will remain rather weak. Initial convective development will probably occur within the post-frontal upslope flow regime during the early to mid afternoon. This activity should spread east and likely expand during the late afternoon into the evening. With deeply mixed thermodynamic profiles ahead of the front, and steep lapse rates being maintained behind it, high-based thunderstorms with amalgamating outflows are expected. While the bulk of strong 700-500 mb westerlies will lag behind the front, the strengthening flow should support a threat for strong to isolated severe surface gusts before convection wanes after dusk. ..Grams.. 05/16/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1226 PM CDT Thu May 16 2024 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN PARTS OF THE GULF COAST STATES... ...SUMMARY... Scattered severe thunderstorms with a few tornadoes, very large hail, and damaging winds are possible across parts of the Gulf Coast States on Friday through Friday night. ...South-central to Southeast States... A messy severe weather setup is expected on Friday into Friday night amid a series of low-amplitude impulses ejecting within and around the positive-tilt, southern-stream shortwave trough across the southern Great Plains. Synoptic surface pattern appears nebulous and likely driven on the mesoscale by several rounds of convection today through the end of D2. Primary changes with this outlook are to expand severe probabilities west and east, while reducing probabilities across the northern portion of the threat area. An MCS or clustered remnants of an early morning one should be ongoing at 12Z Friday across parts of the central Gulf Coast region. Outflow from this preceding D1 activity will serve as the focus for renewed thunderstorm development later in the day. Most guidance suggests a separate area of upstream convection may be ongoing or will develop by midday across parts of south TX and the TX Gulf Coast along and behind the composite outflow/cold front that will surge southeast in TX on D1. With the fastest mid-level southwesterlies expected to overlie the western to central Gulf Coast during the first half of the period, supercells capable of very large hail will be possible. This threat should be focused in a narrow corridor along the TX Gulf Coast initially, and then develop later in the afternoon to evening in the central Gulf Coast. Some of this latter activity will have relatively greater potential for tornado/wind threats, focused along the outflow in the wake of the early-morning MCS. Additional isolated to scattered thunderstorm development should occur within the post-frontal/outflow air mass centered on parts of the Red River Valley and in south-central TX near the Rio Grande. This activity will likely be aided by the embedded low-amplitude impulses within the southern-stream shortwave trough. Residual buoyancy should be adequate for an isolated hail/wind threat amid more muted deep-layer shear closer to the trough axis. ...Northern Great Plains... A vigorous, northern-stream shortwave trough will move across the northern Rockies into the Prairie Provinces and adjacent parts of MT/ND through early Saturday. Primary surface cyclone will occlude over SK/MB, with secondary cyclogenesis occurring near the SD/WY/MT border area along the trailing Pacific cold front. With only modified moisture return ahead of the front, MLCAPE will remain rather weak. Initial convective development will probably occur within the post-frontal upslope flow regime during the early to mid afternoon. This activity should spread east and likely expand during the late afternoon into the evening. With deeply mixed thermodynamic profiles ahead of the front, and steep lapse rates being maintained behind it, high-based thunderstorms with amalgamating outflows are expected. While the bulk of strong 700-500 mb westerlies will lag behind the front, the strengthening flow should support a threat for strong to isolated severe surface gusts before convection wanes after dusk. ..Grams.. 05/16/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1226 PM CDT Thu May 16 2024 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN PARTS OF THE GULF COAST STATES... ...SUMMARY... Scattered severe thunderstorms with a few tornadoes, very large hail, and damaging winds are possible across parts of the Gulf Coast States on Friday through Friday night. ...South-central to Southeast States... A messy severe weather setup is expected on Friday into Friday night amid a series of low-amplitude impulses ejecting within and around the positive-tilt, southern-stream shortwave trough across the southern Great Plains. Synoptic surface pattern appears nebulous and likely driven on the mesoscale by several rounds of convection today through the end of D2. Primary changes with this outlook are to expand severe probabilities west and east, while reducing probabilities across the northern portion of the threat area. An MCS or clustered remnants of an early morning one should be ongoing at 12Z Friday across parts of the central Gulf Coast region. Outflow from this preceding D1 activity will serve as the focus for renewed thunderstorm development later in the day. Most guidance suggests a separate area of upstream convection may be ongoing or will develop by midday across parts of south TX and the TX Gulf Coast along and behind the composite outflow/cold front that will surge southeast in TX on D1. With the fastest mid-level southwesterlies expected to overlie the western to central Gulf Coast during the first half of the period, supercells capable of very large hail will be possible. This threat should be focused in a narrow corridor along the TX Gulf Coast initially, and then develop later in the afternoon to evening in the central Gulf Coast. Some of this latter activity will have relatively greater potential for tornado/wind threats, focused along the outflow in the wake of the early-morning MCS. Additional isolated to scattered thunderstorm development should occur within the post-frontal/outflow air mass centered on parts of the Red River Valley and in south-central TX near the Rio Grande. This activity will likely be aided by the embedded low-amplitude impulses within the southern-stream shortwave trough. Residual buoyancy should be adequate for an isolated hail/wind threat amid more muted deep-layer shear closer to the trough axis. ...Northern Great Plains... A vigorous, northern-stream shortwave trough will move across the northern Rockies into the Prairie Provinces and adjacent parts of MT/ND through early Saturday. Primary surface cyclone will occlude over SK/MB, with secondary cyclogenesis occurring near the SD/WY/MT border area along the trailing Pacific cold front. With only modified moisture return ahead of the front, MLCAPE will remain rather weak. Initial convective development will probably occur within the post-frontal upslope flow regime during the early to mid afternoon. This activity should spread east and likely expand during the late afternoon into the evening. With deeply mixed thermodynamic profiles ahead of the front, and steep lapse rates being maintained behind it, high-based thunderstorms with amalgamating outflows are expected. While the bulk of strong 700-500 mb westerlies will lag behind the front, the strengthening flow should support a threat for strong to isolated severe surface gusts before convection wanes after dusk. ..Grams.. 05/16/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1226 PM CDT Thu May 16 2024 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN PARTS OF THE GULF COAST STATES... ...SUMMARY... Scattered severe thunderstorms with a few tornadoes, very large hail, and damaging winds are possible across parts of the Gulf Coast States on Friday through Friday night. ...South-central to Southeast States... A messy severe weather setup is expected on Friday into Friday night amid a series of low-amplitude impulses ejecting within and around the positive-tilt, southern-stream shortwave trough across the southern Great Plains. Synoptic surface pattern appears nebulous and likely driven on the mesoscale by several rounds of convection today through the end of D2. Primary changes with this outlook are to expand severe probabilities west and east, while reducing probabilities across the northern portion of the threat area. An MCS or clustered remnants of an early morning one should be ongoing at 12Z Friday across parts of the central Gulf Coast region. Outflow from this preceding D1 activity will serve as the focus for renewed thunderstorm development later in the day. Most guidance suggests a separate area of upstream convection may be ongoing or will develop by midday across parts of south TX and the TX Gulf Coast along and behind the composite outflow/cold front that will surge southeast in TX on D1. With the fastest mid-level southwesterlies expected to overlie the western to central Gulf Coast during the first half of the period, supercells capable of very large hail will be possible. This threat should be focused in a narrow corridor along the TX Gulf Coast initially, and then develop later in the afternoon to evening in the central Gulf Coast. Some of this latter activity will have relatively greater potential for tornado/wind threats, focused along the outflow in the wake of the early-morning MCS. Additional isolated to scattered thunderstorm development should occur within the post-frontal/outflow air mass centered on parts of the Red River Valley and in south-central TX near the Rio Grande. This activity will likely be aided by the embedded low-amplitude impulses within the southern-stream shortwave trough. Residual buoyancy should be adequate for an isolated hail/wind threat amid more muted deep-layer shear closer to the trough axis. ...Northern Great Plains... A vigorous, northern-stream shortwave trough will move across the northern Rockies into the Prairie Provinces and adjacent parts of MT/ND through early Saturday. Primary surface cyclone will occlude over SK/MB, with secondary cyclogenesis occurring near the SD/WY/MT border area along the trailing Pacific cold front. With only modified moisture return ahead of the front, MLCAPE will remain rather weak. Initial convective development will probably occur within the post-frontal upslope flow regime during the early to mid afternoon. This activity should spread east and likely expand during the late afternoon into the evening. With deeply mixed thermodynamic profiles ahead of the front, and steep lapse rates being maintained behind it, high-based thunderstorms with amalgamating outflows are expected. While the bulk of strong 700-500 mb westerlies will lag behind the front, the strengthening flow should support a threat for strong to isolated severe surface gusts before convection wanes after dusk. ..Grams.. 05/16/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1226 PM CDT Thu May 16 2024 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN PARTS OF THE GULF COAST STATES... ...SUMMARY... Scattered severe thunderstorms with a few tornadoes, very large hail, and damaging winds are possible across parts of the Gulf Coast States on Friday through Friday night. ...South-central to Southeast States... A messy severe weather setup is expected on Friday into Friday night amid a series of low-amplitude impulses ejecting within and around the positive-tilt, southern-stream shortwave trough across the southern Great Plains. Synoptic surface pattern appears nebulous and likely driven on the mesoscale by several rounds of convection today through the end of D2. Primary changes with this outlook are to expand severe probabilities west and east, while reducing probabilities across the northern portion of the threat area. An MCS or clustered remnants of an early morning one should be ongoing at 12Z Friday across parts of the central Gulf Coast region. Outflow from this preceding D1 activity will serve as the focus for renewed thunderstorm development later in the day. Most guidance suggests a separate area of upstream convection may be ongoing or will develop by midday across parts of south TX and the TX Gulf Coast along and behind the composite outflow/cold front that will surge southeast in TX on D1. With the fastest mid-level southwesterlies expected to overlie the western to central Gulf Coast during the first half of the period, supercells capable of very large hail will be possible. This threat should be focused in a narrow corridor along the TX Gulf Coast initially, and then develop later in the afternoon to evening in the central Gulf Coast. Some of this latter activity will have relatively greater potential for tornado/wind threats, focused along the outflow in the wake of the early-morning MCS. Additional isolated to scattered thunderstorm development should occur within the post-frontal/outflow air mass centered on parts of the Red River Valley and in south-central TX near the Rio Grande. This activity will likely be aided by the embedded low-amplitude impulses within the southern-stream shortwave trough. Residual buoyancy should be adequate for an isolated hail/wind threat amid more muted deep-layer shear closer to the trough axis. ...Northern Great Plains... A vigorous, northern-stream shortwave trough will move across the northern Rockies into the Prairie Provinces and adjacent parts of MT/ND through early Saturday. Primary surface cyclone will occlude over SK/MB, with secondary cyclogenesis occurring near the SD/WY/MT border area along the trailing Pacific cold front. With only modified moisture return ahead of the front, MLCAPE will remain rather weak. Initial convective development will probably occur within the post-frontal upslope flow regime during the early to mid afternoon. This activity should spread east and likely expand during the late afternoon into the evening. With deeply mixed thermodynamic profiles ahead of the front, and steep lapse rates being maintained behind it, high-based thunderstorms with amalgamating outflows are expected. While the bulk of strong 700-500 mb westerlies will lag behind the front, the strengthening flow should support a threat for strong to isolated severe surface gusts before convection wanes after dusk. ..Grams.. 05/16/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1226 PM CDT Thu May 16 2024 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN PARTS OF THE GULF COAST STATES... ...SUMMARY... Scattered severe thunderstorms with a few tornadoes, very large hail, and damaging winds are possible across parts of the Gulf Coast States on Friday through Friday night. ...South-central to Southeast States... A messy severe weather setup is expected on Friday into Friday night amid a series of low-amplitude impulses ejecting within and around the positive-tilt, southern-stream shortwave trough across the southern Great Plains. Synoptic surface pattern appears nebulous and likely driven on the mesoscale by several rounds of convection today through the end of D2. Primary changes with this outlook are to expand severe probabilities west and east, while reducing probabilities across the northern portion of the threat area. An MCS or clustered remnants of an early morning one should be ongoing at 12Z Friday across parts of the central Gulf Coast region. Outflow from this preceding D1 activity will serve as the focus for renewed thunderstorm development later in the day. Most guidance suggests a separate area of upstream convection may be ongoing or will develop by midday across parts of south TX and the TX Gulf Coast along and behind the composite outflow/cold front that will surge southeast in TX on D1. With the fastest mid-level southwesterlies expected to overlie the western to central Gulf Coast during the first half of the period, supercells capable of very large hail will be possible. This threat should be focused in a narrow corridor along the TX Gulf Coast initially, and then develop later in the afternoon to evening in the central Gulf Coast. Some of this latter activity will have relatively greater potential for tornado/wind threats, focused along the outflow in the wake of the early-morning MCS. Additional isolated to scattered thunderstorm development should occur within the post-frontal/outflow air mass centered on parts of the Red River Valley and in south-central TX near the Rio Grande. This activity will likely be aided by the embedded low-amplitude impulses within the southern-stream shortwave trough. Residual buoyancy should be adequate for an isolated hail/wind threat amid more muted deep-layer shear closer to the trough axis. ...Northern Great Plains... A vigorous, northern-stream shortwave trough will move across the northern Rockies into the Prairie Provinces and adjacent parts of MT/ND through early Saturday. Primary surface cyclone will occlude over SK/MB, with secondary cyclogenesis occurring near the SD/WY/MT border area along the trailing Pacific cold front. With only modified moisture return ahead of the front, MLCAPE will remain rather weak. Initial convective development will probably occur within the post-frontal upslope flow regime during the early to mid afternoon. This activity should spread east and likely expand during the late afternoon into the evening. With deeply mixed thermodynamic profiles ahead of the front, and steep lapse rates being maintained behind it, high-based thunderstorms with amalgamating outflows are expected. While the bulk of strong 700-500 mb westerlies will lag behind the front, the strengthening flow should support a threat for strong to isolated severe surface gusts before convection wanes after dusk. ..Grams.. 05/16/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1226 PM CDT Thu May 16 2024 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN PARTS OF THE GULF COAST STATES... ...SUMMARY... Scattered severe thunderstorms with a few tornadoes, very large hail, and damaging winds are possible across parts of the Gulf Coast States on Friday through Friday night. ...South-central to Southeast States... A messy severe weather setup is expected on Friday into Friday night amid a series of low-amplitude impulses ejecting within and around the positive-tilt, southern-stream shortwave trough across the southern Great Plains. Synoptic surface pattern appears nebulous and likely driven on the mesoscale by several rounds of convection today through the end of D2. Primary changes with this outlook are to expand severe probabilities west and east, while reducing probabilities across the northern portion of the threat area. An MCS or clustered remnants of an early morning one should be ongoing at 12Z Friday across parts of the central Gulf Coast region. Outflow from this preceding D1 activity will serve as the focus for renewed thunderstorm development later in the day. Most guidance suggests a separate area of upstream convection may be ongoing or will develop by midday across parts of south TX and the TX Gulf Coast along and behind the composite outflow/cold front that will surge southeast in TX on D1. With the fastest mid-level southwesterlies expected to overlie the western to central Gulf Coast during the first half of the period, supercells capable of very large hail will be possible. This threat should be focused in a narrow corridor along the TX Gulf Coast initially, and then develop later in the afternoon to evening in the central Gulf Coast. Some of this latter activity will have relatively greater potential for tornado/wind threats, focused along the outflow in the wake of the early-morning MCS. Additional isolated to scattered thunderstorm development should occur within the post-frontal/outflow air mass centered on parts of the Red River Valley and in south-central TX near the Rio Grande. This activity will likely be aided by the embedded low-amplitude impulses within the southern-stream shortwave trough. Residual buoyancy should be adequate for an isolated hail/wind threat amid more muted deep-layer shear closer to the trough axis. ...Northern Great Plains... A vigorous, northern-stream shortwave trough will move across the northern Rockies into the Prairie Provinces and adjacent parts of MT/ND through early Saturday. Primary surface cyclone will occlude over SK/MB, with secondary cyclogenesis occurring near the SD/WY/MT border area along the trailing Pacific cold front. With only modified moisture return ahead of the front, MLCAPE will remain rather weak. Initial convective development will probably occur within the post-frontal upslope flow regime during the early to mid afternoon. This activity should spread east and likely expand during the late afternoon into the evening. With deeply mixed thermodynamic profiles ahead of the front, and steep lapse rates being maintained behind it, high-based thunderstorms with amalgamating outflows are expected. While the bulk of strong 700-500 mb westerlies will lag behind the front, the strengthening flow should support a threat for strong to isolated severe surface gusts before convection wanes after dusk. ..Grams.. 05/16/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1226 PM CDT Thu May 16 2024 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN PARTS OF THE GULF COAST STATES... ...SUMMARY... Scattered severe thunderstorms with a few tornadoes, very large hail, and damaging winds are possible across parts of the Gulf Coast States on Friday through Friday night. ...South-central to Southeast States... A messy severe weather setup is expected on Friday into Friday night amid a series of low-amplitude impulses ejecting within and around the positive-tilt, southern-stream shortwave trough across the southern Great Plains. Synoptic surface pattern appears nebulous and likely driven on the mesoscale by several rounds of convection today through the end of D2. Primary changes with this outlook are to expand severe probabilities west and east, while reducing probabilities across the northern portion of the threat area. An MCS or clustered remnants of an early morning one should be ongoing at 12Z Friday across parts of the central Gulf Coast region. Outflow from this preceding D1 activity will serve as the focus for renewed thunderstorm development later in the day. Most guidance suggests a separate area of upstream convection may be ongoing or will develop by midday across parts of south TX and the TX Gulf Coast along and behind the composite outflow/cold front that will surge southeast in TX on D1. With the fastest mid-level southwesterlies expected to overlie the western to central Gulf Coast during the first half of the period, supercells capable of very large hail will be possible. This threat should be focused in a narrow corridor along the TX Gulf Coast initially, and then develop later in the afternoon to evening in the central Gulf Coast. Some of this latter activity will have relatively greater potential for tornado/wind threats, focused along the outflow in the wake of the early-morning MCS. Additional isolated to scattered thunderstorm development should occur within the post-frontal/outflow air mass centered on parts of the Red River Valley and in south-central TX near the Rio Grande. This activity will likely be aided by the embedded low-amplitude impulses within the southern-stream shortwave trough. Residual buoyancy should be adequate for an isolated hail/wind threat amid more muted deep-layer shear closer to the trough axis. ...Northern Great Plains... A vigorous, northern-stream shortwave trough will move across the northern Rockies into the Prairie Provinces and adjacent parts of MT/ND through early Saturday. Primary surface cyclone will occlude over SK/MB, with secondary cyclogenesis occurring near the SD/WY/MT border area along the trailing Pacific cold front. With only modified moisture return ahead of the front, MLCAPE will remain rather weak. Initial convective development will probably occur within the post-frontal upslope flow regime during the early to mid afternoon. This activity should spread east and likely expand during the late afternoon into the evening. With deeply mixed thermodynamic profiles ahead of the front, and steep lapse rates being maintained behind it, high-based thunderstorms with amalgamating outflows are expected. While the bulk of strong 700-500 mb westerlies will lag behind the front, the strengthening flow should support a threat for strong to isolated severe surface gusts before convection wanes after dusk. ..Grams.. 05/16/2024 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1141 AM CDT Thu May 16 2024 Valid 161700Z - 171200Z ...1700Z Update... A cold front has moved through most of the Permian Basin this morning, with a dryline already pushing eastward into the lower Trans Pecos and Big Bend region. This eastward moving trend of the dryline will continue through afternoon as mostly clear skies allow for good to excellent mixing conditions. Very warm afternoon temperatures from the Davis Mountains southward into the Big Bend, along with dewpoints in the upper teens to low 20s, will result in RH dropping as low as the single digits. West to northwest sustained 15-20 mph winds are still anticipated, with localized Critical sustained winds of 20-25 mph later this afternoon near and south of the Davis Mountains. The only minor change to the Elevated area was to eliminate a small portion of the northern extent based on the current position of the cold front and its slow progression to the south throughout the afternoon. ..Barnes/Nauslar.. 05/16/2024 .PREV DISCUSSION... /ISSUED 0121 AM CDT Thu May 16 2024/ ...Synopsis... A mid-level trough will traverse the southern Plains as a weak surface low develops near the Rio Grande today. Behind the low, isallobaric and downslope northwesterly flow will overspread the Trans Pecos region of Texas during the afternoon. 15+ mph sustained northwesterly surface winds will coincide with 10-20 percent RH and dry fuels, warranting the continuation of Elevated highlights. ...Please see www.spc.noaa.gov/fire for graphic product... Read more