Severe Storms

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0415 PM CDT Thu Jun 20 2024 Valid 221200Z - 281200Z At least low chances of wetting rains are expected to continue into early this weekend across portions of the Southwest and southern Rockies within a moisture plume associated with the remnants of Alberto. Further west and north across the Great Basin and the rest of the Desert Southwest, hot and dry conditions will be present under a mid to upper-level ridge D3/Saturday. The pattern will begin to shift by D4/Sunday, as a Pacific mid to upper-level shortwave trough and jet max in its base move onshore near northern WA. An associated dry, cold front will traverse WA and OR Sunday. Both a tightening surface pressure gradient and momentum transfer from aloft within subsidence behind the trough axis will lead to breezy, downslope flow developing across the Cascades and into the Columbia Basin. Fuel states are expected to deteriorate within the aforementioned regions. Therefore, at least low critical probabilities remain in the forecast. In addition, if model trends continue to suggest slightly stronger mid-level flow over WA, a small area of 70 percent critical probabilities may be introduced in subsequent forecasts within the lower fuel moisture content of the southwestern Columbia Basin of WA. Ahead of the cold front across the Upper Snake River Plain, warm, dry, and breezy conditions are anticipated within a well-mixed air mass. Fuels across this region are less receptive, but any ignitions may have the opportunity to spread quickly, as sustained speeds at or above 20 mph persist for several hours there in conjunction with single-digits RH. Furthermore, modest flow aloft and a tightening pressure gradient over southern ID behind the cold front D5/Monday will continue to support low critical probabilities within the Upper Snake River Plain. Confidence in the large-scale pattern decreases slightly D6-D8, although hot and dry, fuel-curing conditions appear likely over the Southwest and most of the Great Basin under the influence of upper ridging. Critical probabilities could return to the extended periods mid to late next week, as another north Pacific mid to upper-level low moves onshore. ..Barnes.. 06/20/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0415 PM CDT Thu Jun 20 2024 Valid 221200Z - 281200Z At least low chances of wetting rains are expected to continue into early this weekend across portions of the Southwest and southern Rockies within a moisture plume associated with the remnants of Alberto. Further west and north across the Great Basin and the rest of the Desert Southwest, hot and dry conditions will be present under a mid to upper-level ridge D3/Saturday. The pattern will begin to shift by D4/Sunday, as a Pacific mid to upper-level shortwave trough and jet max in its base move onshore near northern WA. An associated dry, cold front will traverse WA and OR Sunday. Both a tightening surface pressure gradient and momentum transfer from aloft within subsidence behind the trough axis will lead to breezy, downslope flow developing across the Cascades and into the Columbia Basin. Fuel states are expected to deteriorate within the aforementioned regions. Therefore, at least low critical probabilities remain in the forecast. In addition, if model trends continue to suggest slightly stronger mid-level flow over WA, a small area of 70 percent critical probabilities may be introduced in subsequent forecasts within the lower fuel moisture content of the southwestern Columbia Basin of WA. Ahead of the cold front across the Upper Snake River Plain, warm, dry, and breezy conditions are anticipated within a well-mixed air mass. Fuels across this region are less receptive, but any ignitions may have the opportunity to spread quickly, as sustained speeds at or above 20 mph persist for several hours there in conjunction with single-digits RH. Furthermore, modest flow aloft and a tightening pressure gradient over southern ID behind the cold front D5/Monday will continue to support low critical probabilities within the Upper Snake River Plain. Confidence in the large-scale pattern decreases slightly D6-D8, although hot and dry, fuel-curing conditions appear likely over the Southwest and most of the Great Basin under the influence of upper ridging. Critical probabilities could return to the extended periods mid to late next week, as another north Pacific mid to upper-level low moves onshore. ..Barnes.. 06/20/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0415 PM CDT Thu Jun 20 2024 Valid 221200Z - 281200Z At least low chances of wetting rains are expected to continue into early this weekend across portions of the Southwest and southern Rockies within a moisture plume associated with the remnants of Alberto. Further west and north across the Great Basin and the rest of the Desert Southwest, hot and dry conditions will be present under a mid to upper-level ridge D3/Saturday. The pattern will begin to shift by D4/Sunday, as a Pacific mid to upper-level shortwave trough and jet max in its base move onshore near northern WA. An associated dry, cold front will traverse WA and OR Sunday. Both a tightening surface pressure gradient and momentum transfer from aloft within subsidence behind the trough axis will lead to breezy, downslope flow developing across the Cascades and into the Columbia Basin. Fuel states are expected to deteriorate within the aforementioned regions. Therefore, at least low critical probabilities remain in the forecast. In addition, if model trends continue to suggest slightly stronger mid-level flow over WA, a small area of 70 percent critical probabilities may be introduced in subsequent forecasts within the lower fuel moisture content of the southwestern Columbia Basin of WA. Ahead of the cold front across the Upper Snake River Plain, warm, dry, and breezy conditions are anticipated within a well-mixed air mass. Fuels across this region are less receptive, but any ignitions may have the opportunity to spread quickly, as sustained speeds at or above 20 mph persist for several hours there in conjunction with single-digits RH. Furthermore, modest flow aloft and a tightening pressure gradient over southern ID behind the cold front D5/Monday will continue to support low critical probabilities within the Upper Snake River Plain. Confidence in the large-scale pattern decreases slightly D6-D8, although hot and dry, fuel-curing conditions appear likely over the Southwest and most of the Great Basin under the influence of upper ridging. Critical probabilities could return to the extended periods mid to late next week, as another north Pacific mid to upper-level low moves onshore. ..Barnes.. 06/20/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0415 PM CDT Thu Jun 20 2024 Valid 221200Z - 281200Z At least low chances of wetting rains are expected to continue into early this weekend across portions of the Southwest and southern Rockies within a moisture plume associated with the remnants of Alberto. Further west and north across the Great Basin and the rest of the Desert Southwest, hot and dry conditions will be present under a mid to upper-level ridge D3/Saturday. The pattern will begin to shift by D4/Sunday, as a Pacific mid to upper-level shortwave trough and jet max in its base move onshore near northern WA. An associated dry, cold front will traverse WA and OR Sunday. Both a tightening surface pressure gradient and momentum transfer from aloft within subsidence behind the trough axis will lead to breezy, downslope flow developing across the Cascades and into the Columbia Basin. Fuel states are expected to deteriorate within the aforementioned regions. Therefore, at least low critical probabilities remain in the forecast. In addition, if model trends continue to suggest slightly stronger mid-level flow over WA, a small area of 70 percent critical probabilities may be introduced in subsequent forecasts within the lower fuel moisture content of the southwestern Columbia Basin of WA. Ahead of the cold front across the Upper Snake River Plain, warm, dry, and breezy conditions are anticipated within a well-mixed air mass. Fuels across this region are less receptive, but any ignitions may have the opportunity to spread quickly, as sustained speeds at or above 20 mph persist for several hours there in conjunction with single-digits RH. Furthermore, modest flow aloft and a tightening pressure gradient over southern ID behind the cold front D5/Monday will continue to support low critical probabilities within the Upper Snake River Plain. Confidence in the large-scale pattern decreases slightly D6-D8, although hot and dry, fuel-curing conditions appear likely over the Southwest and most of the Great Basin under the influence of upper ridging. Critical probabilities could return to the extended periods mid to late next week, as another north Pacific mid to upper-level low moves onshore. ..Barnes.. 06/20/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0415 PM CDT Thu Jun 20 2024 Valid 221200Z - 281200Z At least low chances of wetting rains are expected to continue into early this weekend across portions of the Southwest and southern Rockies within a moisture plume associated with the remnants of Alberto. Further west and north across the Great Basin and the rest of the Desert Southwest, hot and dry conditions will be present under a mid to upper-level ridge D3/Saturday. The pattern will begin to shift by D4/Sunday, as a Pacific mid to upper-level shortwave trough and jet max in its base move onshore near northern WA. An associated dry, cold front will traverse WA and OR Sunday. Both a tightening surface pressure gradient and momentum transfer from aloft within subsidence behind the trough axis will lead to breezy, downslope flow developing across the Cascades and into the Columbia Basin. Fuel states are expected to deteriorate within the aforementioned regions. Therefore, at least low critical probabilities remain in the forecast. In addition, if model trends continue to suggest slightly stronger mid-level flow over WA, a small area of 70 percent critical probabilities may be introduced in subsequent forecasts within the lower fuel moisture content of the southwestern Columbia Basin of WA. Ahead of the cold front across the Upper Snake River Plain, warm, dry, and breezy conditions are anticipated within a well-mixed air mass. Fuels across this region are less receptive, but any ignitions may have the opportunity to spread quickly, as sustained speeds at or above 20 mph persist for several hours there in conjunction with single-digits RH. Furthermore, modest flow aloft and a tightening pressure gradient over southern ID behind the cold front D5/Monday will continue to support low critical probabilities within the Upper Snake River Plain. Confidence in the large-scale pattern decreases slightly D6-D8, although hot and dry, fuel-curing conditions appear likely over the Southwest and most of the Great Basin under the influence of upper ridging. Critical probabilities could return to the extended periods mid to late next week, as another north Pacific mid to upper-level low moves onshore. ..Barnes.. 06/20/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0415 PM CDT Thu Jun 20 2024 Valid 221200Z - 281200Z At least low chances of wetting rains are expected to continue into early this weekend across portions of the Southwest and southern Rockies within a moisture plume associated with the remnants of Alberto. Further west and north across the Great Basin and the rest of the Desert Southwest, hot and dry conditions will be present under a mid to upper-level ridge D3/Saturday. The pattern will begin to shift by D4/Sunday, as a Pacific mid to upper-level shortwave trough and jet max in its base move onshore near northern WA. An associated dry, cold front will traverse WA and OR Sunday. Both a tightening surface pressure gradient and momentum transfer from aloft within subsidence behind the trough axis will lead to breezy, downslope flow developing across the Cascades and into the Columbia Basin. Fuel states are expected to deteriorate within the aforementioned regions. Therefore, at least low critical probabilities remain in the forecast. In addition, if model trends continue to suggest slightly stronger mid-level flow over WA, a small area of 70 percent critical probabilities may be introduced in subsequent forecasts within the lower fuel moisture content of the southwestern Columbia Basin of WA. Ahead of the cold front across the Upper Snake River Plain, warm, dry, and breezy conditions are anticipated within a well-mixed air mass. Fuels across this region are less receptive, but any ignitions may have the opportunity to spread quickly, as sustained speeds at or above 20 mph persist for several hours there in conjunction with single-digits RH. Furthermore, modest flow aloft and a tightening pressure gradient over southern ID behind the cold front D5/Monday will continue to support low critical probabilities within the Upper Snake River Plain. Confidence in the large-scale pattern decreases slightly D6-D8, although hot and dry, fuel-curing conditions appear likely over the Southwest and most of the Great Basin under the influence of upper ridging. Critical probabilities could return to the extended periods mid to late next week, as another north Pacific mid to upper-level low moves onshore. ..Barnes.. 06/20/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0415 PM CDT Thu Jun 20 2024 Valid 221200Z - 281200Z At least low chances of wetting rains are expected to continue into early this weekend across portions of the Southwest and southern Rockies within a moisture plume associated with the remnants of Alberto. Further west and north across the Great Basin and the rest of the Desert Southwest, hot and dry conditions will be present under a mid to upper-level ridge D3/Saturday. The pattern will begin to shift by D4/Sunday, as a Pacific mid to upper-level shortwave trough and jet max in its base move onshore near northern WA. An associated dry, cold front will traverse WA and OR Sunday. Both a tightening surface pressure gradient and momentum transfer from aloft within subsidence behind the trough axis will lead to breezy, downslope flow developing across the Cascades and into the Columbia Basin. Fuel states are expected to deteriorate within the aforementioned regions. Therefore, at least low critical probabilities remain in the forecast. In addition, if model trends continue to suggest slightly stronger mid-level flow over WA, a small area of 70 percent critical probabilities may be introduced in subsequent forecasts within the lower fuel moisture content of the southwestern Columbia Basin of WA. Ahead of the cold front across the Upper Snake River Plain, warm, dry, and breezy conditions are anticipated within a well-mixed air mass. Fuels across this region are less receptive, but any ignitions may have the opportunity to spread quickly, as sustained speeds at or above 20 mph persist for several hours there in conjunction with single-digits RH. Furthermore, modest flow aloft and a tightening pressure gradient over southern ID behind the cold front D5/Monday will continue to support low critical probabilities within the Upper Snake River Plain. Confidence in the large-scale pattern decreases slightly D6-D8, although hot and dry, fuel-curing conditions appear likely over the Southwest and most of the Great Basin under the influence of upper ridging. Critical probabilities could return to the extended periods mid to late next week, as another north Pacific mid to upper-level low moves onshore. ..Barnes.. 06/20/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0415 PM CDT Thu Jun 20 2024 Valid 221200Z - 281200Z At least low chances of wetting rains are expected to continue into early this weekend across portions of the Southwest and southern Rockies within a moisture plume associated with the remnants of Alberto. Further west and north across the Great Basin and the rest of the Desert Southwest, hot and dry conditions will be present under a mid to upper-level ridge D3/Saturday. The pattern will begin to shift by D4/Sunday, as a Pacific mid to upper-level shortwave trough and jet max in its base move onshore near northern WA. An associated dry, cold front will traverse WA and OR Sunday. Both a tightening surface pressure gradient and momentum transfer from aloft within subsidence behind the trough axis will lead to breezy, downslope flow developing across the Cascades and into the Columbia Basin. Fuel states are expected to deteriorate within the aforementioned regions. Therefore, at least low critical probabilities remain in the forecast. In addition, if model trends continue to suggest slightly stronger mid-level flow over WA, a small area of 70 percent critical probabilities may be introduced in subsequent forecasts within the lower fuel moisture content of the southwestern Columbia Basin of WA. Ahead of the cold front across the Upper Snake River Plain, warm, dry, and breezy conditions are anticipated within a well-mixed air mass. Fuels across this region are less receptive, but any ignitions may have the opportunity to spread quickly, as sustained speeds at or above 20 mph persist for several hours there in conjunction with single-digits RH. Furthermore, modest flow aloft and a tightening pressure gradient over southern ID behind the cold front D5/Monday will continue to support low critical probabilities within the Upper Snake River Plain. Confidence in the large-scale pattern decreases slightly D6-D8, although hot and dry, fuel-curing conditions appear likely over the Southwest and most of the Great Basin under the influence of upper ridging. Critical probabilities could return to the extended periods mid to late next week, as another north Pacific mid to upper-level low moves onshore. ..Barnes.. 06/20/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0415 PM CDT Thu Jun 20 2024 Valid 221200Z - 281200Z At least low chances of wetting rains are expected to continue into early this weekend across portions of the Southwest and southern Rockies within a moisture plume associated with the remnants of Alberto. Further west and north across the Great Basin and the rest of the Desert Southwest, hot and dry conditions will be present under a mid to upper-level ridge D3/Saturday. The pattern will begin to shift by D4/Sunday, as a Pacific mid to upper-level shortwave trough and jet max in its base move onshore near northern WA. An associated dry, cold front will traverse WA and OR Sunday. Both a tightening surface pressure gradient and momentum transfer from aloft within subsidence behind the trough axis will lead to breezy, downslope flow developing across the Cascades and into the Columbia Basin. Fuel states are expected to deteriorate within the aforementioned regions. Therefore, at least low critical probabilities remain in the forecast. In addition, if model trends continue to suggest slightly stronger mid-level flow over WA, a small area of 70 percent critical probabilities may be introduced in subsequent forecasts within the lower fuel moisture content of the southwestern Columbia Basin of WA. Ahead of the cold front across the Upper Snake River Plain, warm, dry, and breezy conditions are anticipated within a well-mixed air mass. Fuels across this region are less receptive, but any ignitions may have the opportunity to spread quickly, as sustained speeds at or above 20 mph persist for several hours there in conjunction with single-digits RH. Furthermore, modest flow aloft and a tightening pressure gradient over southern ID behind the cold front D5/Monday will continue to support low critical probabilities within the Upper Snake River Plain. Confidence in the large-scale pattern decreases slightly D6-D8, although hot and dry, fuel-curing conditions appear likely over the Southwest and most of the Great Basin under the influence of upper ridging. Critical probabilities could return to the extended periods mid to late next week, as another north Pacific mid to upper-level low moves onshore. ..Barnes.. 06/20/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

WW 0439 Status Updates
STATUS REPORT ON WW 439 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..LYONS..06/20/24 ATTN...WFO...BOU...CYS...LBF...UNR... STATUS REPORT FOR WS 439 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS COC075-087-115-123-202140- CO . COLORADO COUNTIES INCLUDED ARE LOGAN MORGAN SEDGWICK WELD NEC007-013-033-045-049-069-105-123-157-161-165-202140- NE . NEBRASKA COUNTIES INCLUDED ARE BANNER BOX BUTTE CHEYENNE DAWES DEUEL GARDEN KIMBALL MORRILL SCOTTS BLUFF SHERIDAN SIOUX SDC047-102-202140- SD . SOUTH DAKOTA COUNTIES INCLUDED ARE FALL RIVER OGLALA LAKOTA Read more

WW 0439 Status Updates
STATUS REPORT ON WW 439 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..LYONS..06/20/24 ATTN...WFO...BOU...CYS...LBF...UNR... STATUS REPORT FOR WS 439 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS COC075-087-115-123-202140- CO . COLORADO COUNTIES INCLUDED ARE LOGAN MORGAN SEDGWICK WELD NEC007-013-033-045-049-069-105-123-157-161-165-202140- NE . NEBRASKA COUNTIES INCLUDED ARE BANNER BOX BUTTE CHEYENNE DAWES DEUEL GARDEN KIMBALL MORRILL SCOTTS BLUFF SHERIDAN SIOUX SDC047-102-202140- SD . SOUTH DAKOTA COUNTIES INCLUDED ARE FALL RIVER OGLALA LAKOTA Read more

MD 1345 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR WEST CENTRAL MONTANA
Mesoscale Discussion 1345 NWS Storm Prediction Center Norman OK 0238 PM CDT Thu Jun 20 2024 Areas affected...West Central Montana Concerning...Severe potential...Watch unlikely Valid 201938Z - 202045Z Probability of Watch Issuance...20 percent SUMMARY...Thunderstorm development over the mountains has increased over the last half hour, with the potential for a supercell or two to develop in Central MT. Isolated hail and damaging winds are possible, especially with isolated convection that moves eastward into the better buoyancy and shear. WW issuance is not likely due to uncertainty in spatial coverage of severe threats. DISCUSSION...Thunderstorms are increasing in coverage along the mountains in far western MT, and a more mature thunderstorm has developed over Judith Basin county. Due to proximity to the upper trough, RAP forecast profiles show cold temperatures aloft supportive of SBCAPE > 1000 J/kg. Deep layer shear over Central and Eastern MT are in the range of 40-50kts, decreasing towards the west over the higher terrain. Any convection that tracks further east into Central MT should encounter better combinations of shear and buoyancy, resulting in an isolated threat for 1+ inch hail and 60+ MPH wind gusts. However, due to uncertainty in spatial coverage of organized severe storms, WW issuance is not expected at this time. ..Halbert/Lyons/Hart.. 06/20/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...BYZ...GGW...TFX...MSO... LAT...LON 46841349 47991355 48831361 48991326 48751257 47661225 47391140 47471071 47720948 47830872 47540826 46990815 46520826 46310857 46120922 45960985 45681080 45801233 46151329 46841349 Read more

WW 0438 Status Updates
STATUS REPORT ON WW 438 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..SQUITIERI..06/20/24 ATTN...WFO...BOX...GYX...CAR...BTV...ALY... STATUS REPORT FOR WS 438 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MEC001-005-007-009-011-013-015-017-019-021-023-025-027-031- 202140- ME . MAINE COUNTIES INCLUDED ARE ANDROSCOGGIN CUMBERLAND FRANKLIN HANCOCK KENNEBEC KNOX LINCOLN OXFORD PENOBSCOT PISCATAQUIS SAGADAHOC SOMERSET WALDO YORK MAC009-011-017-027-202140- MA . MASSACHUSETTS COUNTIES INCLUDED ARE ESSEX FRANKLIN MIDDLESEX WORCESTER NHC001-003-005-007-009-011-013-015-017-019-202140- NH . NEW HAMPSHIRE COUNTIES INCLUDED ARE Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0301 PM CDT Thu Jun 20 2024 Valid 202000Z - 211200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTH-CENTRAL HIGH PLAINS AND NORTHEAST/NEW ENGLAND...THE FOUR CORNERS...AND SOUTHERN LOWER MICHIGAN... ...SUMMARY... Storms may produce scattered damaging wind gusts over parts of the Northeast and New England mainly this afternoon. Scattered severe storms are also expected over parts of the north-central High Plains, the Four Corners, and southern Lower Michigan. ...20z outlook update discussion... The only changes made to the outlook are described below. Otherwise, no change was made to the previous outlook and forecast reasoning appears on track. ...Southern Lower Michigan... Surface boundary has become draped west to east across southern Lower MI with a reservoir of lower 70s deg F surface dewpoints immediately in the vicinity of the front. Surface streamline analysis indicates weak surface convergence and preferential storm development is expected along the boundary through the early evening. Strong to severe gusts (50-65 mph) capable of wind damage will be the primary hazard with the stronger water-laden downdrafts. The ongoing thunderstorm activity will likely slowly migrate east-southeast into southeast Lower MI towards early evening. ...Four Corners... The northwest periphery of seasonably high moisture will continue to support additional storm development through the early to mid evening across this region. The development of steep 0-3 km lapse rates and a wind profile promoting organized single cells/multicells and perhaps transient supercells, will foster a risk for severe gusts (60-75 mph) through the early to mid evening with the stronger microbursts. ...Northeast Colorado... Have expanded the Slight-Risk equivalent severe probabilities farther south-southwest to east of the Front Range north/northeast of Denver. Storms will move east of the higher terrain of the Front Range and potentially pose a risk for wind/hail with the stronger storms. ..Smith.. 06/20/2024 .PREV DISCUSSION... /ISSUED 1112 AM CDT Thu Jun 20 2024/ ...Eastern NY and New England... Visible satellite imagery shows strong daytime heating occurring across all of New England and parts of NY/PA. A well-defined MCV currently over eastern Lake Ontario will track eastward into this warm and very humid air mass (dewpoints in the low 70s), where afternoon MLCAPE values will exceed 2000 J/kg. Scattered to numerous thunderstorms are expected, with storms spreading eastward through the afternoon towards the coast of southern ME/NH/MA. Winds aloft are not particularly strong, suggest early activity may be rather disorganized. However, eventual congealing of outflow will likely result in locally damaging wind gusts. Hail will also be possible in the strongest cells. Please refer to MCD #1340 for further details. ...Central High Plains... Latest surface analysis shows south-southeasterly low-level winds across the NE Panhandle and southeast WY, where dewpoints are in the 50s and lower 60s. This will help maintain a moist/unstable air mass in the area, yielding afternoon MLCAPE values of around 1500 J/kg. Scattered thunderstorms are expected to form over southeast WY by 20z, where sufficient deep-layer shear and steep lapse rates will favor supercell structures capable of very large hail and perhaps a tornado. Storms will track eastward into the NE Panhandle and southern SD through the evening, with an increasing risk of damaging winds (possibly exceeding 65kt). ...Western CO... Moderately strong southwesterly low/mid-level flow is present today across western CO, where full heating and diurnal destabilization will occur. Morning models continue to show scattered or greater thunderstorms coverage this afternoon, in a deeply mixed environment. Several fast-moving high-based thunderstorms are expected, with a risk of locally severe winds in the stronger cores. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0301 PM CDT Thu Jun 20 2024 Valid 202000Z - 211200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTH-CENTRAL HIGH PLAINS AND NORTHEAST/NEW ENGLAND...THE FOUR CORNERS...AND SOUTHERN LOWER MICHIGAN... ...SUMMARY... Storms may produce scattered damaging wind gusts over parts of the Northeast and New England mainly this afternoon. Scattered severe storms are also expected over parts of the north-central High Plains, the Four Corners, and southern Lower Michigan. ...20z outlook update discussion... The only changes made to the outlook are described below. Otherwise, no change was made to the previous outlook and forecast reasoning appears on track. ...Southern Lower Michigan... Surface boundary has become draped west to east across southern Lower MI with a reservoir of lower 70s deg F surface dewpoints immediately in the vicinity of the front. Surface streamline analysis indicates weak surface convergence and preferential storm development is expected along the boundary through the early evening. Strong to severe gusts (50-65 mph) capable of wind damage will be the primary hazard with the stronger water-laden downdrafts. The ongoing thunderstorm activity will likely slowly migrate east-southeast into southeast Lower MI towards early evening. ...Four Corners... The northwest periphery of seasonably high moisture will continue to support additional storm development through the early to mid evening across this region. The development of steep 0-3 km lapse rates and a wind profile promoting organized single cells/multicells and perhaps transient supercells, will foster a risk for severe gusts (60-75 mph) through the early to mid evening with the stronger microbursts. ...Northeast Colorado... Have expanded the Slight-Risk equivalent severe probabilities farther south-southwest to east of the Front Range north/northeast of Denver. Storms will move east of the higher terrain of the Front Range and potentially pose a risk for wind/hail with the stronger storms. ..Smith.. 06/20/2024 .PREV DISCUSSION... /ISSUED 1112 AM CDT Thu Jun 20 2024/ ...Eastern NY and New England... Visible satellite imagery shows strong daytime heating occurring across all of New England and parts of NY/PA. A well-defined MCV currently over eastern Lake Ontario will track eastward into this warm and very humid air mass (dewpoints in the low 70s), where afternoon MLCAPE values will exceed 2000 J/kg. Scattered to numerous thunderstorms are expected, with storms spreading eastward through the afternoon towards the coast of southern ME/NH/MA. Winds aloft are not particularly strong, suggest early activity may be rather disorganized. However, eventual congealing of outflow will likely result in locally damaging wind gusts. Hail will also be possible in the strongest cells. Please refer to MCD #1340 for further details. ...Central High Plains... Latest surface analysis shows south-southeasterly low-level winds across the NE Panhandle and southeast WY, where dewpoints are in the 50s and lower 60s. This will help maintain a moist/unstable air mass in the area, yielding afternoon MLCAPE values of around 1500 J/kg. Scattered thunderstorms are expected to form over southeast WY by 20z, where sufficient deep-layer shear and steep lapse rates will favor supercell structures capable of very large hail and perhaps a tornado. Storms will track eastward into the NE Panhandle and southern SD through the evening, with an increasing risk of damaging winds (possibly exceeding 65kt). ...Western CO... Moderately strong southwesterly low/mid-level flow is present today across western CO, where full heating and diurnal destabilization will occur. Morning models continue to show scattered or greater thunderstorms coverage this afternoon, in a deeply mixed environment. Several fast-moving high-based thunderstorms are expected, with a risk of locally severe winds in the stronger cores. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0301 PM CDT Thu Jun 20 2024 Valid 202000Z - 211200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTH-CENTRAL HIGH PLAINS AND NORTHEAST/NEW ENGLAND...THE FOUR CORNERS...AND SOUTHERN LOWER MICHIGAN... ...SUMMARY... Storms may produce scattered damaging wind gusts over parts of the Northeast and New England mainly this afternoon. Scattered severe storms are also expected over parts of the north-central High Plains, the Four Corners, and southern Lower Michigan. ...20z outlook update discussion... The only changes made to the outlook are described below. Otherwise, no change was made to the previous outlook and forecast reasoning appears on track. ...Southern Lower Michigan... Surface boundary has become draped west to east across southern Lower MI with a reservoir of lower 70s deg F surface dewpoints immediately in the vicinity of the front. Surface streamline analysis indicates weak surface convergence and preferential storm development is expected along the boundary through the early evening. Strong to severe gusts (50-65 mph) capable of wind damage will be the primary hazard with the stronger water-laden downdrafts. The ongoing thunderstorm activity will likely slowly migrate east-southeast into southeast Lower MI towards early evening. ...Four Corners... The northwest periphery of seasonably high moisture will continue to support additional storm development through the early to mid evening across this region. The development of steep 0-3 km lapse rates and a wind profile promoting organized single cells/multicells and perhaps transient supercells, will foster a risk for severe gusts (60-75 mph) through the early to mid evening with the stronger microbursts. ...Northeast Colorado... Have expanded the Slight-Risk equivalent severe probabilities farther south-southwest to east of the Front Range north/northeast of Denver. Storms will move east of the higher terrain of the Front Range and potentially pose a risk for wind/hail with the stronger storms. ..Smith.. 06/20/2024 .PREV DISCUSSION... /ISSUED 1112 AM CDT Thu Jun 20 2024/ ...Eastern NY and New England... Visible satellite imagery shows strong daytime heating occurring across all of New England and parts of NY/PA. A well-defined MCV currently over eastern Lake Ontario will track eastward into this warm and very humid air mass (dewpoints in the low 70s), where afternoon MLCAPE values will exceed 2000 J/kg. Scattered to numerous thunderstorms are expected, with storms spreading eastward through the afternoon towards the coast of southern ME/NH/MA. Winds aloft are not particularly strong, suggest early activity may be rather disorganized. However, eventual congealing of outflow will likely result in locally damaging wind gusts. Hail will also be possible in the strongest cells. Please refer to MCD #1340 for further details. ...Central High Plains... Latest surface analysis shows south-southeasterly low-level winds across the NE Panhandle and southeast WY, where dewpoints are in the 50s and lower 60s. This will help maintain a moist/unstable air mass in the area, yielding afternoon MLCAPE values of around 1500 J/kg. Scattered thunderstorms are expected to form over southeast WY by 20z, where sufficient deep-layer shear and steep lapse rates will favor supercell structures capable of very large hail and perhaps a tornado. Storms will track eastward into the NE Panhandle and southern SD through the evening, with an increasing risk of damaging winds (possibly exceeding 65kt). ...Western CO... Moderately strong southwesterly low/mid-level flow is present today across western CO, where full heating and diurnal destabilization will occur. Morning models continue to show scattered or greater thunderstorms coverage this afternoon, in a deeply mixed environment. Several fast-moving high-based thunderstorms are expected, with a risk of locally severe winds in the stronger cores. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0301 PM CDT Thu Jun 20 2024 Valid 202000Z - 211200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTH-CENTRAL HIGH PLAINS AND NORTHEAST/NEW ENGLAND...THE FOUR CORNERS...AND SOUTHERN LOWER MICHIGAN... ...SUMMARY... Storms may produce scattered damaging wind gusts over parts of the Northeast and New England mainly this afternoon. Scattered severe storms are also expected over parts of the north-central High Plains, the Four Corners, and southern Lower Michigan. ...20z outlook update discussion... The only changes made to the outlook are described below. Otherwise, no change was made to the previous outlook and forecast reasoning appears on track. ...Southern Lower Michigan... Surface boundary has become draped west to east across southern Lower MI with a reservoir of lower 70s deg F surface dewpoints immediately in the vicinity of the front. Surface streamline analysis indicates weak surface convergence and preferential storm development is expected along the boundary through the early evening. Strong to severe gusts (50-65 mph) capable of wind damage will be the primary hazard with the stronger water-laden downdrafts. The ongoing thunderstorm activity will likely slowly migrate east-southeast into southeast Lower MI towards early evening. ...Four Corners... The northwest periphery of seasonably high moisture will continue to support additional storm development through the early to mid evening across this region. The development of steep 0-3 km lapse rates and a wind profile promoting organized single cells/multicells and perhaps transient supercells, will foster a risk for severe gusts (60-75 mph) through the early to mid evening with the stronger microbursts. ...Northeast Colorado... Have expanded the Slight-Risk equivalent severe probabilities farther south-southwest to east of the Front Range north/northeast of Denver. Storms will move east of the higher terrain of the Front Range and potentially pose a risk for wind/hail with the stronger storms. ..Smith.. 06/20/2024 .PREV DISCUSSION... /ISSUED 1112 AM CDT Thu Jun 20 2024/ ...Eastern NY and New England... Visible satellite imagery shows strong daytime heating occurring across all of New England and parts of NY/PA. A well-defined MCV currently over eastern Lake Ontario will track eastward into this warm and very humid air mass (dewpoints in the low 70s), where afternoon MLCAPE values will exceed 2000 J/kg. Scattered to numerous thunderstorms are expected, with storms spreading eastward through the afternoon towards the coast of southern ME/NH/MA. Winds aloft are not particularly strong, suggest early activity may be rather disorganized. However, eventual congealing of outflow will likely result in locally damaging wind gusts. Hail will also be possible in the strongest cells. Please refer to MCD #1340 for further details. ...Central High Plains... Latest surface analysis shows south-southeasterly low-level winds across the NE Panhandle and southeast WY, where dewpoints are in the 50s and lower 60s. This will help maintain a moist/unstable air mass in the area, yielding afternoon MLCAPE values of around 1500 J/kg. Scattered thunderstorms are expected to form over southeast WY by 20z, where sufficient deep-layer shear and steep lapse rates will favor supercell structures capable of very large hail and perhaps a tornado. Storms will track eastward into the NE Panhandle and southern SD through the evening, with an increasing risk of damaging winds (possibly exceeding 65kt). ...Western CO... Moderately strong southwesterly low/mid-level flow is present today across western CO, where full heating and diurnal destabilization will occur. Morning models continue to show scattered or greater thunderstorms coverage this afternoon, in a deeply mixed environment. Several fast-moving high-based thunderstorms are expected, with a risk of locally severe winds in the stronger cores. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0301 PM CDT Thu Jun 20 2024 Valid 202000Z - 211200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTH-CENTRAL HIGH PLAINS AND NORTHEAST/NEW ENGLAND...THE FOUR CORNERS...AND SOUTHERN LOWER MICHIGAN... ...SUMMARY... Storms may produce scattered damaging wind gusts over parts of the Northeast and New England mainly this afternoon. Scattered severe storms are also expected over parts of the north-central High Plains, the Four Corners, and southern Lower Michigan. ...20z outlook update discussion... The only changes made to the outlook are described below. Otherwise, no change was made to the previous outlook and forecast reasoning appears on track. ...Southern Lower Michigan... Surface boundary has become draped west to east across southern Lower MI with a reservoir of lower 70s deg F surface dewpoints immediately in the vicinity of the front. Surface streamline analysis indicates weak surface convergence and preferential storm development is expected along the boundary through the early evening. Strong to severe gusts (50-65 mph) capable of wind damage will be the primary hazard with the stronger water-laden downdrafts. The ongoing thunderstorm activity will likely slowly migrate east-southeast into southeast Lower MI towards early evening. ...Four Corners... The northwest periphery of seasonably high moisture will continue to support additional storm development through the early to mid evening across this region. The development of steep 0-3 km lapse rates and a wind profile promoting organized single cells/multicells and perhaps transient supercells, will foster a risk for severe gusts (60-75 mph) through the early to mid evening with the stronger microbursts. ...Northeast Colorado... Have expanded the Slight-Risk equivalent severe probabilities farther south-southwest to east of the Front Range north/northeast of Denver. Storms will move east of the higher terrain of the Front Range and potentially pose a risk for wind/hail with the stronger storms. ..Smith.. 06/20/2024 .PREV DISCUSSION... /ISSUED 1112 AM CDT Thu Jun 20 2024/ ...Eastern NY and New England... Visible satellite imagery shows strong daytime heating occurring across all of New England and parts of NY/PA. A well-defined MCV currently over eastern Lake Ontario will track eastward into this warm and very humid air mass (dewpoints in the low 70s), where afternoon MLCAPE values will exceed 2000 J/kg. Scattered to numerous thunderstorms are expected, with storms spreading eastward through the afternoon towards the coast of southern ME/NH/MA. Winds aloft are not particularly strong, suggest early activity may be rather disorganized. However, eventual congealing of outflow will likely result in locally damaging wind gusts. Hail will also be possible in the strongest cells. Please refer to MCD #1340 for further details. ...Central High Plains... Latest surface analysis shows south-southeasterly low-level winds across the NE Panhandle and southeast WY, where dewpoints are in the 50s and lower 60s. This will help maintain a moist/unstable air mass in the area, yielding afternoon MLCAPE values of around 1500 J/kg. Scattered thunderstorms are expected to form over southeast WY by 20z, where sufficient deep-layer shear and steep lapse rates will favor supercell structures capable of very large hail and perhaps a tornado. Storms will track eastward into the NE Panhandle and southern SD through the evening, with an increasing risk of damaging winds (possibly exceeding 65kt). ...Western CO... Moderately strong southwesterly low/mid-level flow is present today across western CO, where full heating and diurnal destabilization will occur. Morning models continue to show scattered or greater thunderstorms coverage this afternoon, in a deeply mixed environment. Several fast-moving high-based thunderstorms are expected, with a risk of locally severe winds in the stronger cores. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0301 PM CDT Thu Jun 20 2024 Valid 202000Z - 211200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTH-CENTRAL HIGH PLAINS AND NORTHEAST/NEW ENGLAND...THE FOUR CORNERS...AND SOUTHERN LOWER MICHIGAN... ...SUMMARY... Storms may produce scattered damaging wind gusts over parts of the Northeast and New England mainly this afternoon. Scattered severe storms are also expected over parts of the north-central High Plains, the Four Corners, and southern Lower Michigan. ...20z outlook update discussion... The only changes made to the outlook are described below. Otherwise, no change was made to the previous outlook and forecast reasoning appears on track. ...Southern Lower Michigan... Surface boundary has become draped west to east across southern Lower MI with a reservoir of lower 70s deg F surface dewpoints immediately in the vicinity of the front. Surface streamline analysis indicates weak surface convergence and preferential storm development is expected along the boundary through the early evening. Strong to severe gusts (50-65 mph) capable of wind damage will be the primary hazard with the stronger water-laden downdrafts. The ongoing thunderstorm activity will likely slowly migrate east-southeast into southeast Lower MI towards early evening. ...Four Corners... The northwest periphery of seasonably high moisture will continue to support additional storm development through the early to mid evening across this region. The development of steep 0-3 km lapse rates and a wind profile promoting organized single cells/multicells and perhaps transient supercells, will foster a risk for severe gusts (60-75 mph) through the early to mid evening with the stronger microbursts. ...Northeast Colorado... Have expanded the Slight-Risk equivalent severe probabilities farther south-southwest to east of the Front Range north/northeast of Denver. Storms will move east of the higher terrain of the Front Range and potentially pose a risk for wind/hail with the stronger storms. ..Smith.. 06/20/2024 .PREV DISCUSSION... /ISSUED 1112 AM CDT Thu Jun 20 2024/ ...Eastern NY and New England... Visible satellite imagery shows strong daytime heating occurring across all of New England and parts of NY/PA. A well-defined MCV currently over eastern Lake Ontario will track eastward into this warm and very humid air mass (dewpoints in the low 70s), where afternoon MLCAPE values will exceed 2000 J/kg. Scattered to numerous thunderstorms are expected, with storms spreading eastward through the afternoon towards the coast of southern ME/NH/MA. Winds aloft are not particularly strong, suggest early activity may be rather disorganized. However, eventual congealing of outflow will likely result in locally damaging wind gusts. Hail will also be possible in the strongest cells. Please refer to MCD #1340 for further details. ...Central High Plains... Latest surface analysis shows south-southeasterly low-level winds across the NE Panhandle and southeast WY, where dewpoints are in the 50s and lower 60s. This will help maintain a moist/unstable air mass in the area, yielding afternoon MLCAPE values of around 1500 J/kg. Scattered thunderstorms are expected to form over southeast WY by 20z, where sufficient deep-layer shear and steep lapse rates will favor supercell structures capable of very large hail and perhaps a tornado. Storms will track eastward into the NE Panhandle and southern SD through the evening, with an increasing risk of damaging winds (possibly exceeding 65kt). ...Western CO... Moderately strong southwesterly low/mid-level flow is present today across western CO, where full heating and diurnal destabilization will occur. Morning models continue to show scattered or greater thunderstorms coverage this afternoon, in a deeply mixed environment. Several fast-moving high-based thunderstorms are expected, with a risk of locally severe winds in the stronger cores. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0301 PM CDT Thu Jun 20 2024 Valid 202000Z - 211200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTH-CENTRAL HIGH PLAINS AND NORTHEAST/NEW ENGLAND...THE FOUR CORNERS...AND SOUTHERN LOWER MICHIGAN... ...SUMMARY... Storms may produce scattered damaging wind gusts over parts of the Northeast and New England mainly this afternoon. Scattered severe storms are also expected over parts of the north-central High Plains, the Four Corners, and southern Lower Michigan. ...20z outlook update discussion... The only changes made to the outlook are described below. Otherwise, no change was made to the previous outlook and forecast reasoning appears on track. ...Southern Lower Michigan... Surface boundary has become draped west to east across southern Lower MI with a reservoir of lower 70s deg F surface dewpoints immediately in the vicinity of the front. Surface streamline analysis indicates weak surface convergence and preferential storm development is expected along the boundary through the early evening. Strong to severe gusts (50-65 mph) capable of wind damage will be the primary hazard with the stronger water-laden downdrafts. The ongoing thunderstorm activity will likely slowly migrate east-southeast into southeast Lower MI towards early evening. ...Four Corners... The northwest periphery of seasonably high moisture will continue to support additional storm development through the early to mid evening across this region. The development of steep 0-3 km lapse rates and a wind profile promoting organized single cells/multicells and perhaps transient supercells, will foster a risk for severe gusts (60-75 mph) through the early to mid evening with the stronger microbursts. ...Northeast Colorado... Have expanded the Slight-Risk equivalent severe probabilities farther south-southwest to east of the Front Range north/northeast of Denver. Storms will move east of the higher terrain of the Front Range and potentially pose a risk for wind/hail with the stronger storms. ..Smith.. 06/20/2024 .PREV DISCUSSION... /ISSUED 1112 AM CDT Thu Jun 20 2024/ ...Eastern NY and New England... Visible satellite imagery shows strong daytime heating occurring across all of New England and parts of NY/PA. A well-defined MCV currently over eastern Lake Ontario will track eastward into this warm and very humid air mass (dewpoints in the low 70s), where afternoon MLCAPE values will exceed 2000 J/kg. Scattered to numerous thunderstorms are expected, with storms spreading eastward through the afternoon towards the coast of southern ME/NH/MA. Winds aloft are not particularly strong, suggest early activity may be rather disorganized. However, eventual congealing of outflow will likely result in locally damaging wind gusts. Hail will also be possible in the strongest cells. Please refer to MCD #1340 for further details. ...Central High Plains... Latest surface analysis shows south-southeasterly low-level winds across the NE Panhandle and southeast WY, where dewpoints are in the 50s and lower 60s. This will help maintain a moist/unstable air mass in the area, yielding afternoon MLCAPE values of around 1500 J/kg. Scattered thunderstorms are expected to form over southeast WY by 20z, where sufficient deep-layer shear and steep lapse rates will favor supercell structures capable of very large hail and perhaps a tornado. Storms will track eastward into the NE Panhandle and southern SD through the evening, with an increasing risk of damaging winds (possibly exceeding 65kt). ...Western CO... Moderately strong southwesterly low/mid-level flow is present today across western CO, where full heating and diurnal destabilization will occur. Morning models continue to show scattered or greater thunderstorms coverage this afternoon, in a deeply mixed environment. Several fast-moving high-based thunderstorms are expected, with a risk of locally severe winds in the stronger cores. Read more