Aggregator

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0741 AM CDT Wed May 29 2024 Valid 291300Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON THROUGH LATE EVENING ACROSS THE NORTHERN/CENTRAL HIGH PLAINS AND IN SOUTHWEST TX... ...SUMMARY... Scattered strong storms posing a risk for severe hail and wind appear likely across the northern and central High Plains late this afternoon and evening. Isolated large hail will also be possible in southwest Texas. ...Northern/central High Plains this afternoon into tonight... A midlevel shortwave trough over the northern Rockies will continue eastward with associated lee troughing expected across the northern/central High Plains through the afternoon/evening. A corridor of modest low-level moistening (boundary-layer dewpoints potentially into the 50s) will occur along and east of the lee trough, where afternoon surface temperatures will warm well into the 80s beneath steep midlevel lapse rates and result in SBCAPE of 1000-2000 J/kg with minimal convective inhibition. Scattered high-based thunderstorms are expected to form by mid afternoon near the lee trough and spread eastward through late evening, with some potential for storms to be maintained into tonight in association with a strengthening low-level jet and warm advection. Occasional severe outflow gusts of 60-70 mph and isolated large hail of 1-1.5 inches in diameter will be the main threats with primarily multicell clusters and possibly some weak supercell structures given weak-modest deep-layer vertical shear (effective shear generally 25-30 kt). ...Southern Plains today into tonight... Widespread convective overturning has occurred across TX in the past 24 hours, with the remnants of a large MCS now weakening just off the lower TX coast. Lingering low-level moisture and steep lapse rates across the Trans-Pecos (northwest of the MCS remnants) could support isolated thunderstorm development this afternoon near the Davis Mountains. Here, MLCAPE in excess of 2000 J/kg and sufficiently long hodographs will favor splitting supercells capable of producing isolated large hail, potentially 2 inches in diameter or larger. Otherwise, marginally severe storm development may occur near the upper TX coast later today with a remnant MCV on the edge of the richer low-level moisture. The southern portion of the central High Plains convection may persist through tonight and grow into a loosely organized MCS from western KS southward into the TX Panhandle and western OK, where the storms will encounter gradually increasing low-level moisture in a warm advection regime. A few strong gusts and isolated/marginally severe hail may occur with the strongest embedded storms. ...Central Appalachians/Mid-Atlantic this afternoon... A midlevel trough now over OH will progress eastward to the Mid-Atlantic coast by early tonight. Low-level moisture will be relatively limited in advance of the midlevel trough and a weak surface reflection, but surface heating and steepening of low-level lapse rates will contribute to weak SBCAPE of 250-500 J/kg. Scattered, low-topped thunderstorms will be possible this afternoon across PA/MD/VA and convection will spread to the coast this evening. The steep low-level lapse rates will promote gusty outflow winds, but severe/damaging winds appear unlikely given marginal buoyancy and weak low-level flow to limit momentum transfer. ..Thompson/Grams.. 05/29/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0741 AM CDT Wed May 29 2024 Valid 291300Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON THROUGH LATE EVENING ACROSS THE NORTHERN/CENTRAL HIGH PLAINS AND IN SOUTHWEST TX... ...SUMMARY... Scattered strong storms posing a risk for severe hail and wind appear likely across the northern and central High Plains late this afternoon and evening. Isolated large hail will also be possible in southwest Texas. ...Northern/central High Plains this afternoon into tonight... A midlevel shortwave trough over the northern Rockies will continue eastward with associated lee troughing expected across the northern/central High Plains through the afternoon/evening. A corridor of modest low-level moistening (boundary-layer dewpoints potentially into the 50s) will occur along and east of the lee trough, where afternoon surface temperatures will warm well into the 80s beneath steep midlevel lapse rates and result in SBCAPE of 1000-2000 J/kg with minimal convective inhibition. Scattered high-based thunderstorms are expected to form by mid afternoon near the lee trough and spread eastward through late evening, with some potential for storms to be maintained into tonight in association with a strengthening low-level jet and warm advection. Occasional severe outflow gusts of 60-70 mph and isolated large hail of 1-1.5 inches in diameter will be the main threats with primarily multicell clusters and possibly some weak supercell structures given weak-modest deep-layer vertical shear (effective shear generally 25-30 kt). ...Southern Plains today into tonight... Widespread convective overturning has occurred across TX in the past 24 hours, with the remnants of a large MCS now weakening just off the lower TX coast. Lingering low-level moisture and steep lapse rates across the Trans-Pecos (northwest of the MCS remnants) could support isolated thunderstorm development this afternoon near the Davis Mountains. Here, MLCAPE in excess of 2000 J/kg and sufficiently long hodographs will favor splitting supercells capable of producing isolated large hail, potentially 2 inches in diameter or larger. Otherwise, marginally severe storm development may occur near the upper TX coast later today with a remnant MCV on the edge of the richer low-level moisture. The southern portion of the central High Plains convection may persist through tonight and grow into a loosely organized MCS from western KS southward into the TX Panhandle and western OK, where the storms will encounter gradually increasing low-level moisture in a warm advection regime. A few strong gusts and isolated/marginally severe hail may occur with the strongest embedded storms. ...Central Appalachians/Mid-Atlantic this afternoon... A midlevel trough now over OH will progress eastward to the Mid-Atlantic coast by early tonight. Low-level moisture will be relatively limited in advance of the midlevel trough and a weak surface reflection, but surface heating and steepening of low-level lapse rates will contribute to weak SBCAPE of 250-500 J/kg. Scattered, low-topped thunderstorms will be possible this afternoon across PA/MD/VA and convection will spread to the coast this evening. The steep low-level lapse rates will promote gusty outflow winds, but severe/damaging winds appear unlikely given marginal buoyancy and weak low-level flow to limit momentum transfer. ..Thompson/Grams.. 05/29/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0741 AM CDT Wed May 29 2024 Valid 291300Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON THROUGH LATE EVENING ACROSS THE NORTHERN/CENTRAL HIGH PLAINS AND IN SOUTHWEST TX... ...SUMMARY... Scattered strong storms posing a risk for severe hail and wind appear likely across the northern and central High Plains late this afternoon and evening. Isolated large hail will also be possible in southwest Texas. ...Northern/central High Plains this afternoon into tonight... A midlevel shortwave trough over the northern Rockies will continue eastward with associated lee troughing expected across the northern/central High Plains through the afternoon/evening. A corridor of modest low-level moistening (boundary-layer dewpoints potentially into the 50s) will occur along and east of the lee trough, where afternoon surface temperatures will warm well into the 80s beneath steep midlevel lapse rates and result in SBCAPE of 1000-2000 J/kg with minimal convective inhibition. Scattered high-based thunderstorms are expected to form by mid afternoon near the lee trough and spread eastward through late evening, with some potential for storms to be maintained into tonight in association with a strengthening low-level jet and warm advection. Occasional severe outflow gusts of 60-70 mph and isolated large hail of 1-1.5 inches in diameter will be the main threats with primarily multicell clusters and possibly some weak supercell structures given weak-modest deep-layer vertical shear (effective shear generally 25-30 kt). ...Southern Plains today into tonight... Widespread convective overturning has occurred across TX in the past 24 hours, with the remnants of a large MCS now weakening just off the lower TX coast. Lingering low-level moisture and steep lapse rates across the Trans-Pecos (northwest of the MCS remnants) could support isolated thunderstorm development this afternoon near the Davis Mountains. Here, MLCAPE in excess of 2000 J/kg and sufficiently long hodographs will favor splitting supercells capable of producing isolated large hail, potentially 2 inches in diameter or larger. Otherwise, marginally severe storm development may occur near the upper TX coast later today with a remnant MCV on the edge of the richer low-level moisture. The southern portion of the central High Plains convection may persist through tonight and grow into a loosely organized MCS from western KS southward into the TX Panhandle and western OK, where the storms will encounter gradually increasing low-level moisture in a warm advection regime. A few strong gusts and isolated/marginally severe hail may occur with the strongest embedded storms. ...Central Appalachians/Mid-Atlantic this afternoon... A midlevel trough now over OH will progress eastward to the Mid-Atlantic coast by early tonight. Low-level moisture will be relatively limited in advance of the midlevel trough and a weak surface reflection, but surface heating and steepening of low-level lapse rates will contribute to weak SBCAPE of 250-500 J/kg. Scattered, low-topped thunderstorms will be possible this afternoon across PA/MD/VA and convection will spread to the coast this evening. The steep low-level lapse rates will promote gusty outflow winds, but severe/damaging winds appear unlikely given marginal buoyancy and weak low-level flow to limit momentum transfer. ..Thompson/Grams.. 05/29/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0741 AM CDT Wed May 29 2024 Valid 291300Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON THROUGH LATE EVENING ACROSS THE NORTHERN/CENTRAL HIGH PLAINS AND IN SOUTHWEST TX... ...SUMMARY... Scattered strong storms posing a risk for severe hail and wind appear likely across the northern and central High Plains late this afternoon and evening. Isolated large hail will also be possible in southwest Texas. ...Northern/central High Plains this afternoon into tonight... A midlevel shortwave trough over the northern Rockies will continue eastward with associated lee troughing expected across the northern/central High Plains through the afternoon/evening. A corridor of modest low-level moistening (boundary-layer dewpoints potentially into the 50s) will occur along and east of the lee trough, where afternoon surface temperatures will warm well into the 80s beneath steep midlevel lapse rates and result in SBCAPE of 1000-2000 J/kg with minimal convective inhibition. Scattered high-based thunderstorms are expected to form by mid afternoon near the lee trough and spread eastward through late evening, with some potential for storms to be maintained into tonight in association with a strengthening low-level jet and warm advection. Occasional severe outflow gusts of 60-70 mph and isolated large hail of 1-1.5 inches in diameter will be the main threats with primarily multicell clusters and possibly some weak supercell structures given weak-modest deep-layer vertical shear (effective shear generally 25-30 kt). ...Southern Plains today into tonight... Widespread convective overturning has occurred across TX in the past 24 hours, with the remnants of a large MCS now weakening just off the lower TX coast. Lingering low-level moisture and steep lapse rates across the Trans-Pecos (northwest of the MCS remnants) could support isolated thunderstorm development this afternoon near the Davis Mountains. Here, MLCAPE in excess of 2000 J/kg and sufficiently long hodographs will favor splitting supercells capable of producing isolated large hail, potentially 2 inches in diameter or larger. Otherwise, marginally severe storm development may occur near the upper TX coast later today with a remnant MCV on the edge of the richer low-level moisture. The southern portion of the central High Plains convection may persist through tonight and grow into a loosely organized MCS from western KS southward into the TX Panhandle and western OK, where the storms will encounter gradually increasing low-level moisture in a warm advection regime. A few strong gusts and isolated/marginally severe hail may occur with the strongest embedded storms. ...Central Appalachians/Mid-Atlantic this afternoon... A midlevel trough now over OH will progress eastward to the Mid-Atlantic coast by early tonight. Low-level moisture will be relatively limited in advance of the midlevel trough and a weak surface reflection, but surface heating and steepening of low-level lapse rates will contribute to weak SBCAPE of 250-500 J/kg. Scattered, low-topped thunderstorms will be possible this afternoon across PA/MD/VA and convection will spread to the coast this evening. The steep low-level lapse rates will promote gusty outflow winds, but severe/damaging winds appear unlikely given marginal buoyancy and weak low-level flow to limit momentum transfer. ..Thompson/Grams.. 05/29/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0741 AM CDT Wed May 29 2024 Valid 291300Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON THROUGH LATE EVENING ACROSS THE NORTHERN/CENTRAL HIGH PLAINS AND IN SOUTHWEST TX... ...SUMMARY... Scattered strong storms posing a risk for severe hail and wind appear likely across the northern and central High Plains late this afternoon and evening. Isolated large hail will also be possible in southwest Texas. ...Northern/central High Plains this afternoon into tonight... A midlevel shortwave trough over the northern Rockies will continue eastward with associated lee troughing expected across the northern/central High Plains through the afternoon/evening. A corridor of modest low-level moistening (boundary-layer dewpoints potentially into the 50s) will occur along and east of the lee trough, where afternoon surface temperatures will warm well into the 80s beneath steep midlevel lapse rates and result in SBCAPE of 1000-2000 J/kg with minimal convective inhibition. Scattered high-based thunderstorms are expected to form by mid afternoon near the lee trough and spread eastward through late evening, with some potential for storms to be maintained into tonight in association with a strengthening low-level jet and warm advection. Occasional severe outflow gusts of 60-70 mph and isolated large hail of 1-1.5 inches in diameter will be the main threats with primarily multicell clusters and possibly some weak supercell structures given weak-modest deep-layer vertical shear (effective shear generally 25-30 kt). ...Southern Plains today into tonight... Widespread convective overturning has occurred across TX in the past 24 hours, with the remnants of a large MCS now weakening just off the lower TX coast. Lingering low-level moisture and steep lapse rates across the Trans-Pecos (northwest of the MCS remnants) could support isolated thunderstorm development this afternoon near the Davis Mountains. Here, MLCAPE in excess of 2000 J/kg and sufficiently long hodographs will favor splitting supercells capable of producing isolated large hail, potentially 2 inches in diameter or larger. Otherwise, marginally severe storm development may occur near the upper TX coast later today with a remnant MCV on the edge of the richer low-level moisture. The southern portion of the central High Plains convection may persist through tonight and grow into a loosely organized MCS from western KS southward into the TX Panhandle and western OK, where the storms will encounter gradually increasing low-level moisture in a warm advection regime. A few strong gusts and isolated/marginally severe hail may occur with the strongest embedded storms. ...Central Appalachians/Mid-Atlantic this afternoon... A midlevel trough now over OH will progress eastward to the Mid-Atlantic coast by early tonight. Low-level moisture will be relatively limited in advance of the midlevel trough and a weak surface reflection, but surface heating and steepening of low-level lapse rates will contribute to weak SBCAPE of 250-500 J/kg. Scattered, low-topped thunderstorms will be possible this afternoon across PA/MD/VA and convection will spread to the coast this evening. The steep low-level lapse rates will promote gusty outflow winds, but severe/damaging winds appear unlikely given marginal buoyancy and weak low-level flow to limit momentum transfer. ..Thompson/Grams.. 05/29/2024 Read more

000
ABPZ20 KNHC 291136
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
500 AM PDT Wed May 29 2024

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

Tropical cyclone formation is not expected during the next 7 days.

$$
Forecaster D. Zelinsky

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0358 AM CDT Wed May 29 2024 Valid 011200Z - 061200Z ...DISCUSSION... The potential evolution of the mid/upper flow by this weekend into next week remains rather uncertain, based on the continuing substantial spread evident in the medium-range model output. It currently appears most certain that the westerlies may undergo substantial amplification across the mid-latitude Pacific into western North America by the middle of next week, including broad large-scale mid-level ridging building across the eastern Pacific through much of the U.S. Intermountain West and Rockies. This may be preceded by a period of more zonal flow near the Canadian/U.S. border area, with a couple of embedded, progressive short wave troughs. Models suggest that these waves may be accompanied by surface cyclogenesis to the lee of the Canadian/northern U.S. Rockies. Initial cyclogenesis to the lee of the northern U.S. Rockies, through the middle Missouri and northern Great Plains Red River Valley, on Sunday may be modest. However, it appears possible that increasing flow/vertical shear, and destabilization associated with low-level moisture return, could become sufficient to support at least some organized severe thunderstorm potential by Sunday afternoon into Sunday night. Guidance is suggestive that surface cyclogenesis with the trailing wave next Tuesday may be stronger, but it remains unclear whether this will be focused to the lee of the northern U.S. Rockies or to the lee of the Canadian Rockies into the Canadian Prairies. Due to the considerable uncertainties, severe probabilities are being maintained at less than 15 percent through this period. However, this could change in later outlook updates for this period, particularly in the Sunday through Tuesday time frame. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0358 AM CDT Wed May 29 2024 Valid 011200Z - 061200Z ...DISCUSSION... The potential evolution of the mid/upper flow by this weekend into next week remains rather uncertain, based on the continuing substantial spread evident in the medium-range model output. It currently appears most certain that the westerlies may undergo substantial amplification across the mid-latitude Pacific into western North America by the middle of next week, including broad large-scale mid-level ridging building across the eastern Pacific through much of the U.S. Intermountain West and Rockies. This may be preceded by a period of more zonal flow near the Canadian/U.S. border area, with a couple of embedded, progressive short wave troughs. Models suggest that these waves may be accompanied by surface cyclogenesis to the lee of the Canadian/northern U.S. Rockies. Initial cyclogenesis to the lee of the northern U.S. Rockies, through the middle Missouri and northern Great Plains Red River Valley, on Sunday may be modest. However, it appears possible that increasing flow/vertical shear, and destabilization associated with low-level moisture return, could become sufficient to support at least some organized severe thunderstorm potential by Sunday afternoon into Sunday night. Guidance is suggestive that surface cyclogenesis with the trailing wave next Tuesday may be stronger, but it remains unclear whether this will be focused to the lee of the northern U.S. Rockies or to the lee of the Canadian Rockies into the Canadian Prairies. Due to the considerable uncertainties, severe probabilities are being maintained at less than 15 percent through this period. However, this could change in later outlook updates for this period, particularly in the Sunday through Tuesday time frame. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0358 AM CDT Wed May 29 2024 Valid 011200Z - 061200Z ...DISCUSSION... The potential evolution of the mid/upper flow by this weekend into next week remains rather uncertain, based on the continuing substantial spread evident in the medium-range model output. It currently appears most certain that the westerlies may undergo substantial amplification across the mid-latitude Pacific into western North America by the middle of next week, including broad large-scale mid-level ridging building across the eastern Pacific through much of the U.S. Intermountain West and Rockies. This may be preceded by a period of more zonal flow near the Canadian/U.S. border area, with a couple of embedded, progressive short wave troughs. Models suggest that these waves may be accompanied by surface cyclogenesis to the lee of the Canadian/northern U.S. Rockies. Initial cyclogenesis to the lee of the northern U.S. Rockies, through the middle Missouri and northern Great Plains Red River Valley, on Sunday may be modest. However, it appears possible that increasing flow/vertical shear, and destabilization associated with low-level moisture return, could become sufficient to support at least some organized severe thunderstorm potential by Sunday afternoon into Sunday night. Guidance is suggestive that surface cyclogenesis with the trailing wave next Tuesday may be stronger, but it remains unclear whether this will be focused to the lee of the northern U.S. Rockies or to the lee of the Canadian Rockies into the Canadian Prairies. Due to the considerable uncertainties, severe probabilities are being maintained at less than 15 percent through this period. However, this could change in later outlook updates for this period, particularly in the Sunday through Tuesday time frame. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0358 AM CDT Wed May 29 2024 Valid 011200Z - 061200Z ...DISCUSSION... The potential evolution of the mid/upper flow by this weekend into next week remains rather uncertain, based on the continuing substantial spread evident in the medium-range model output. It currently appears most certain that the westerlies may undergo substantial amplification across the mid-latitude Pacific into western North America by the middle of next week, including broad large-scale mid-level ridging building across the eastern Pacific through much of the U.S. Intermountain West and Rockies. This may be preceded by a period of more zonal flow near the Canadian/U.S. border area, with a couple of embedded, progressive short wave troughs. Models suggest that these waves may be accompanied by surface cyclogenesis to the lee of the Canadian/northern U.S. Rockies. Initial cyclogenesis to the lee of the northern U.S. Rockies, through the middle Missouri and northern Great Plains Red River Valley, on Sunday may be modest. However, it appears possible that increasing flow/vertical shear, and destabilization associated with low-level moisture return, could become sufficient to support at least some organized severe thunderstorm potential by Sunday afternoon into Sunday night. Guidance is suggestive that surface cyclogenesis with the trailing wave next Tuesday may be stronger, but it remains unclear whether this will be focused to the lee of the northern U.S. Rockies or to the lee of the Canadian Rockies into the Canadian Prairies. Due to the considerable uncertainties, severe probabilities are being maintained at less than 15 percent through this period. However, this could change in later outlook updates for this period, particularly in the Sunday through Tuesday time frame. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0358 AM CDT Wed May 29 2024 Valid 011200Z - 061200Z ...DISCUSSION... The potential evolution of the mid/upper flow by this weekend into next week remains rather uncertain, based on the continuing substantial spread evident in the medium-range model output. It currently appears most certain that the westerlies may undergo substantial amplification across the mid-latitude Pacific into western North America by the middle of next week, including broad large-scale mid-level ridging building across the eastern Pacific through much of the U.S. Intermountain West and Rockies. This may be preceded by a period of more zonal flow near the Canadian/U.S. border area, with a couple of embedded, progressive short wave troughs. Models suggest that these waves may be accompanied by surface cyclogenesis to the lee of the Canadian/northern U.S. Rockies. Initial cyclogenesis to the lee of the northern U.S. Rockies, through the middle Missouri and northern Great Plains Red River Valley, on Sunday may be modest. However, it appears possible that increasing flow/vertical shear, and destabilization associated with low-level moisture return, could become sufficient to support at least some organized severe thunderstorm potential by Sunday afternoon into Sunday night. Guidance is suggestive that surface cyclogenesis with the trailing wave next Tuesday may be stronger, but it remains unclear whether this will be focused to the lee of the northern U.S. Rockies or to the lee of the Canadian Rockies into the Canadian Prairies. Due to the considerable uncertainties, severe probabilities are being maintained at less than 15 percent through this period. However, this could change in later outlook updates for this period, particularly in the Sunday through Tuesday time frame. Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0226 AM CDT Wed May 29 2024 Valid 311200Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FRIDAY INTO FRIDAY EVENING ACROSS PARTS OF SOUTHERN OKLAHOMA AND MUCH OF NORTH TEXAS THROUGH THE UPPER TEXAS COASTAL PLAIN...WESTERN LOUISIANA AND SOUTHWESTERN ARKANSAS... ...SUMMARY... One or two organized clusters of storms may evolve by Friday morning into afternoon and pose a risk for severe wind and hail continuing across parts of the southern Great Plains into lower Mississippi Valley and Texas Gulf coast by Friday evening. ...Synopsis... Downstream of a lower/mid-tropospheric cyclone forecast to elongate eastward from the northern Canadian Prairies toward western Hudson Bay, it appears that initially prominent mid-level ridging will become suppressed southeastward across Quebec and the lower Great Lakes region. Farther east, amplified mid-level troughing may slowly shift east of the Atlantic Seaboard, but models indicate that a seasonably dry/stable air mass will be maintained across most areas east of the Mississippi Valley through this period. Another surge of cooler and drier air may continue to slowly spread through the upper Mississippi Valley, mid Missouri Valley and central Great Plains. In the southern mid-latitudes, generally weak zonal flow will prevail to the north of suppressed mid/upper ridging across the subtropics. This regime will include at least a couple of low-amplitude waves and perhaps one or two convectively generated perturbations. ...South Central U.S... The 29/00Z NAM, in particular, is suggestive of the development of a significant convective perturbation across and north of the Red River Valley vicinity by 12Z Friday. This may include the evolution of a prominent mesoscale convective vortex, which may be preceded by weakening convection, but trailed by strengthening warm advection driven thunderstorm activity near/northwest of the Wichita Falls vicinity. The NAM then suggests the renewed convective development will undergo significant ensuing intensification and organization, with another developing mesoscale convective vortex and intensifying rear inflow (including to in excess of 60-70+ kt in the 850-700 mb layer) through Friday afternoon across much of North Texas. Other model output is considerably more vague, or displaced, with this potential (e.g., a less dramatic convective signal is evident in the 29/00Z ECMWF, farther to the south across central Texas toward middle Texas coastal areas). While there is considerable uncertainty due to these differences, it appears that the environment will be potentially conducive to this type evolution, as a seasonably moist boundary-layer becomes characterized by large CAPE (2000-4000 J/kg), beneath steep lapse rates associated with an eastward advecting plume of elevated mixed-layer air. If/when it becomes clearer that sub-synoptic developments will evolve anywhere close to what the NAM suggests, severe probabilities may need to be increased in later outlooks for this period. ..Kerr.. 05/29/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0226 AM CDT Wed May 29 2024 Valid 311200Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FRIDAY INTO FRIDAY EVENING ACROSS PARTS OF SOUTHERN OKLAHOMA AND MUCH OF NORTH TEXAS THROUGH THE UPPER TEXAS COASTAL PLAIN...WESTERN LOUISIANA AND SOUTHWESTERN ARKANSAS... ...SUMMARY... One or two organized clusters of storms may evolve by Friday morning into afternoon and pose a risk for severe wind and hail continuing across parts of the southern Great Plains into lower Mississippi Valley and Texas Gulf coast by Friday evening. ...Synopsis... Downstream of a lower/mid-tropospheric cyclone forecast to elongate eastward from the northern Canadian Prairies toward western Hudson Bay, it appears that initially prominent mid-level ridging will become suppressed southeastward across Quebec and the lower Great Lakes region. Farther east, amplified mid-level troughing may slowly shift east of the Atlantic Seaboard, but models indicate that a seasonably dry/stable air mass will be maintained across most areas east of the Mississippi Valley through this period. Another surge of cooler and drier air may continue to slowly spread through the upper Mississippi Valley, mid Missouri Valley and central Great Plains. In the southern mid-latitudes, generally weak zonal flow will prevail to the north of suppressed mid/upper ridging across the subtropics. This regime will include at least a couple of low-amplitude waves and perhaps one or two convectively generated perturbations. ...South Central U.S... The 29/00Z NAM, in particular, is suggestive of the development of a significant convective perturbation across and north of the Red River Valley vicinity by 12Z Friday. This may include the evolution of a prominent mesoscale convective vortex, which may be preceded by weakening convection, but trailed by strengthening warm advection driven thunderstorm activity near/northwest of the Wichita Falls vicinity. The NAM then suggests the renewed convective development will undergo significant ensuing intensification and organization, with another developing mesoscale convective vortex and intensifying rear inflow (including to in excess of 60-70+ kt in the 850-700 mb layer) through Friday afternoon across much of North Texas. Other model output is considerably more vague, or displaced, with this potential (e.g., a less dramatic convective signal is evident in the 29/00Z ECMWF, farther to the south across central Texas toward middle Texas coastal areas). While there is considerable uncertainty due to these differences, it appears that the environment will be potentially conducive to this type evolution, as a seasonably moist boundary-layer becomes characterized by large CAPE (2000-4000 J/kg), beneath steep lapse rates associated with an eastward advecting plume of elevated mixed-layer air. If/when it becomes clearer that sub-synoptic developments will evolve anywhere close to what the NAM suggests, severe probabilities may need to be increased in later outlooks for this period. ..Kerr.. 05/29/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0226 AM CDT Wed May 29 2024 Valid 311200Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FRIDAY INTO FRIDAY EVENING ACROSS PARTS OF SOUTHERN OKLAHOMA AND MUCH OF NORTH TEXAS THROUGH THE UPPER TEXAS COASTAL PLAIN...WESTERN LOUISIANA AND SOUTHWESTERN ARKANSAS... ...SUMMARY... One or two organized clusters of storms may evolve by Friday morning into afternoon and pose a risk for severe wind and hail continuing across parts of the southern Great Plains into lower Mississippi Valley and Texas Gulf coast by Friday evening. ...Synopsis... Downstream of a lower/mid-tropospheric cyclone forecast to elongate eastward from the northern Canadian Prairies toward western Hudson Bay, it appears that initially prominent mid-level ridging will become suppressed southeastward across Quebec and the lower Great Lakes region. Farther east, amplified mid-level troughing may slowly shift east of the Atlantic Seaboard, but models indicate that a seasonably dry/stable air mass will be maintained across most areas east of the Mississippi Valley through this period. Another surge of cooler and drier air may continue to slowly spread through the upper Mississippi Valley, mid Missouri Valley and central Great Plains. In the southern mid-latitudes, generally weak zonal flow will prevail to the north of suppressed mid/upper ridging across the subtropics. This regime will include at least a couple of low-amplitude waves and perhaps one or two convectively generated perturbations. ...South Central U.S... The 29/00Z NAM, in particular, is suggestive of the development of a significant convective perturbation across and north of the Red River Valley vicinity by 12Z Friday. This may include the evolution of a prominent mesoscale convective vortex, which may be preceded by weakening convection, but trailed by strengthening warm advection driven thunderstorm activity near/northwest of the Wichita Falls vicinity. The NAM then suggests the renewed convective development will undergo significant ensuing intensification and organization, with another developing mesoscale convective vortex and intensifying rear inflow (including to in excess of 60-70+ kt in the 850-700 mb layer) through Friday afternoon across much of North Texas. Other model output is considerably more vague, or displaced, with this potential (e.g., a less dramatic convective signal is evident in the 29/00Z ECMWF, farther to the south across central Texas toward middle Texas coastal areas). While there is considerable uncertainty due to these differences, it appears that the environment will be potentially conducive to this type evolution, as a seasonably moist boundary-layer becomes characterized by large CAPE (2000-4000 J/kg), beneath steep lapse rates associated with an eastward advecting plume of elevated mixed-layer air. If/when it becomes clearer that sub-synoptic developments will evolve anywhere close to what the NAM suggests, severe probabilities may need to be increased in later outlooks for this period. ..Kerr.. 05/29/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0226 AM CDT Wed May 29 2024 Valid 311200Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FRIDAY INTO FRIDAY EVENING ACROSS PARTS OF SOUTHERN OKLAHOMA AND MUCH OF NORTH TEXAS THROUGH THE UPPER TEXAS COASTAL PLAIN...WESTERN LOUISIANA AND SOUTHWESTERN ARKANSAS... ...SUMMARY... One or two organized clusters of storms may evolve by Friday morning into afternoon and pose a risk for severe wind and hail continuing across parts of the southern Great Plains into lower Mississippi Valley and Texas Gulf coast by Friday evening. ...Synopsis... Downstream of a lower/mid-tropospheric cyclone forecast to elongate eastward from the northern Canadian Prairies toward western Hudson Bay, it appears that initially prominent mid-level ridging will become suppressed southeastward across Quebec and the lower Great Lakes region. Farther east, amplified mid-level troughing may slowly shift east of the Atlantic Seaboard, but models indicate that a seasonably dry/stable air mass will be maintained across most areas east of the Mississippi Valley through this period. Another surge of cooler and drier air may continue to slowly spread through the upper Mississippi Valley, mid Missouri Valley and central Great Plains. In the southern mid-latitudes, generally weak zonal flow will prevail to the north of suppressed mid/upper ridging across the subtropics. This regime will include at least a couple of low-amplitude waves and perhaps one or two convectively generated perturbations. ...South Central U.S... The 29/00Z NAM, in particular, is suggestive of the development of a significant convective perturbation across and north of the Red River Valley vicinity by 12Z Friday. This may include the evolution of a prominent mesoscale convective vortex, which may be preceded by weakening convection, but trailed by strengthening warm advection driven thunderstorm activity near/northwest of the Wichita Falls vicinity. The NAM then suggests the renewed convective development will undergo significant ensuing intensification and organization, with another developing mesoscale convective vortex and intensifying rear inflow (including to in excess of 60-70+ kt in the 850-700 mb layer) through Friday afternoon across much of North Texas. Other model output is considerably more vague, or displaced, with this potential (e.g., a less dramatic convective signal is evident in the 29/00Z ECMWF, farther to the south across central Texas toward middle Texas coastal areas). While there is considerable uncertainty due to these differences, it appears that the environment will be potentially conducive to this type evolution, as a seasonably moist boundary-layer becomes characterized by large CAPE (2000-4000 J/kg), beneath steep lapse rates associated with an eastward advecting plume of elevated mixed-layer air. If/when it becomes clearer that sub-synoptic developments will evolve anywhere close to what the NAM suggests, severe probabilities may need to be increased in later outlooks for this period. ..Kerr.. 05/29/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0226 AM CDT Wed May 29 2024 Valid 311200Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FRIDAY INTO FRIDAY EVENING ACROSS PARTS OF SOUTHERN OKLAHOMA AND MUCH OF NORTH TEXAS THROUGH THE UPPER TEXAS COASTAL PLAIN...WESTERN LOUISIANA AND SOUTHWESTERN ARKANSAS... ...SUMMARY... One or two organized clusters of storms may evolve by Friday morning into afternoon and pose a risk for severe wind and hail continuing across parts of the southern Great Plains into lower Mississippi Valley and Texas Gulf coast by Friday evening. ...Synopsis... Downstream of a lower/mid-tropospheric cyclone forecast to elongate eastward from the northern Canadian Prairies toward western Hudson Bay, it appears that initially prominent mid-level ridging will become suppressed southeastward across Quebec and the lower Great Lakes region. Farther east, amplified mid-level troughing may slowly shift east of the Atlantic Seaboard, but models indicate that a seasonably dry/stable air mass will be maintained across most areas east of the Mississippi Valley through this period. Another surge of cooler and drier air may continue to slowly spread through the upper Mississippi Valley, mid Missouri Valley and central Great Plains. In the southern mid-latitudes, generally weak zonal flow will prevail to the north of suppressed mid/upper ridging across the subtropics. This regime will include at least a couple of low-amplitude waves and perhaps one or two convectively generated perturbations. ...South Central U.S... The 29/00Z NAM, in particular, is suggestive of the development of a significant convective perturbation across and north of the Red River Valley vicinity by 12Z Friday. This may include the evolution of a prominent mesoscale convective vortex, which may be preceded by weakening convection, but trailed by strengthening warm advection driven thunderstorm activity near/northwest of the Wichita Falls vicinity. The NAM then suggests the renewed convective development will undergo significant ensuing intensification and organization, with another developing mesoscale convective vortex and intensifying rear inflow (including to in excess of 60-70+ kt in the 850-700 mb layer) through Friday afternoon across much of North Texas. Other model output is considerably more vague, or displaced, with this potential (e.g., a less dramatic convective signal is evident in the 29/00Z ECMWF, farther to the south across central Texas toward middle Texas coastal areas). While there is considerable uncertainty due to these differences, it appears that the environment will be potentially conducive to this type evolution, as a seasonably moist boundary-layer becomes characterized by large CAPE (2000-4000 J/kg), beneath steep lapse rates associated with an eastward advecting plume of elevated mixed-layer air. If/when it becomes clearer that sub-synoptic developments will evolve anywhere close to what the NAM suggests, severe probabilities may need to be increased in later outlooks for this period. ..Kerr.. 05/29/2024 Read more

MD 1063 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR TX SOUTH PLAINS
Mesoscale Discussion 1063 NWS Storm Prediction Center Norman OK 0114 AM CDT Wed May 29 2024 Areas affected...TX South Plains Concerning...Severe potential...Watch unlikely Valid 290614Z - 290745Z Probability of Watch Issuance...5 percent SUMMARY...A narrow swath of severe hail and wind may persist through about 3 AM CDT before likely weakening. A watch is not expected. DISCUSSION...Long-lived supercell that produced multiple golf-ball size hail reports in the past hour across Roosevelt County, NM has evolved into a supercell bowing structure in the South Plains west of Lubbock. CAM guidance has handled this particular area of convection quite poorly, with successive runs of the HRRR initializing and then immediately weakening the cell within the first hour. MRMS MESH values have recently diminished to around 2 inches as the bowing structure evolved which suggests the potential for significant severe hail is diminishing. Despite the likely elevated character, a swath of severe wind gusts may occur until the cell finally subsides, which was recently confirmed by a 62 mph gust at the Morton West TX Mesonet site. This appears likely to occur as it shifts away from the instability axis over eastern NM and relatively weaker deep-layer shear with eastern extent per time-series comparison of area VWP data. ..Grams/Thompson.. 05/29/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LUB... LAT...LON 34030273 33960224 33870165 33490122 33120127 33010155 33060196 33310266 33820284 34030273 Read more

WW 0348 Status Updates
STATUS REPORT ON WW 348 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 30 WSW MFE TO 45 NNE MFE. WW 348 WILL BE ALLOWED TO EXPIRE AT 290700Z. ..GRAMS..05/29/24 ATTN...WFO...BRO...EWX...CRP... STATUS REPORT FOR WS 348 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS TXC061-215-249-261-273-355-409-489-290700- TX . TEXAS COUNTIES INCLUDED ARE CAMERON HIDALGO JIM WELLS KENEDY KLEBERG NUECES SAN PATRICIO WILLACY GMZ130-132-135-150-155-170-175-231-232-250-270-290700- CW . ADJACENT COASTAL WATERS INCLUDED ARE GMZ130 GMZ132 GMZ135 GMZ150 Read more

WW 348 SEVERE TSTM TX 290110Z - 290700Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 348 NWS Storm Prediction Center Norman OK 810 PM CDT Tue May 28 2024 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of South and Deep South Texas * Effective this Tuesday night and Wednesday morning from 810 PM until 200 AM CDT. * Primary threats include... Scattered damaging winds and isolated significant gusts to 80 mph likely Scattered large hail and isolated very large hail events to 2 inches in diameter likely SUMMARY...A linear cluster of thunderstorms will likely continue east-southeastward through the Watch area this evening into tonight. Severe gusts ranging from 60-80 mph are possible with the more intense downdrafts. Large hail may accompany the stronger embedded thunderstorm cores. The severe thunderstorm watch area is approximately along and 45 statute miles east and west of a line from 50 miles north northwest of Cotulla TX to 15 miles west southwest of Mcallen TX. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU8). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Severe Thunderstorm Watch means conditions are favorable for severe thunderstorms in and close to the watch area. Persons in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings. Severe thunderstorms can and occasionally do produce tornadoes. && OTHER WATCH INFORMATION...CONTINUE...WW 344...WW 345...WW 346...WW 347... AVIATION...A few severe thunderstorms with hail surface and aloft to 2 inches. Extreme turbulence and surface wind gusts to 70 knots. A few cumulonimbi with maximum tops to 550. Mean storm motion vector 28035. ...Smith Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0113 AM CDT Wed May 29 2024 Valid 301200Z - 311200Z ...NO CRITICAL AREAS... ...Synopsis... Mid-level flow will continue to weaken across the Southwest Thursday, as a mid to upper-level negatively tilted trough progresses east northeastward over the northern Rockies. An associated Pacific cold front will make its way as far south as southwestern UT Thursday morning, and only weak westerly surface winds are expected ahead of it through the afternoon across most of AZ and NM. The exception may be near the Sacramento Mountains of NM, where sustained wind speeds near 15-20 mph are anticipated late in the afternoon/early evening. This is also where single-digit RH will reside. However, confidence is too low to introduce an Elevated area at this time since meteorological fire spread conditions will be brief and fairly isolated. ..Barnes.. 05/29/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more