Severe Storms

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1243 AM CDT Fri Jun 21 2024 Valid 211200Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE NORTHERN HIGH PLAINS TO THE UPPER MISSISSIPPI VALLEY AND OVER THE FOUR CORNERS REGION... ...SUMMARY... Scattered strong to severe storms are expected from parts of the northern High Plains into the upper Mississippi Valley on Friday. Scattered strong/severe thunderstorms are also possible in the Four Corners vicinity. A few strong storms may also be noted into parts of the lower Great Lakes to southern New England. ...Northern High Plains to the upper Mississippi Valley... Latest water-vapor imagery depicts a low-amplitude short-wave trough over eastern WA/OR. This feature is forecast to shift into the northern Rockies later today. Surface high pressure over MB/SK/Dakotas will ensure southeasterly low-level flow deep into MT ahead of the short wave. 40kt 500mb flow will develop across central MT as the ridge flattens and scattered robust convection should easily develop within a flow regime favorable for supercells. Forecast sounding for central MT exhibit favorable deep-layer shear with strong buoyancy and relatively low cloud bases. Scattered supercells should evolve by early afternoon then propagate southeast along the instability axis toward south-central MT by early evening. Very large hail, gusty winds, and even a few tornadoes can be expected. Downstream across the upper MS Valley, low-level warm advection will focus along a frontal zone that is expected to be draped across WI/southern MN into southeast SD. Latest model guidance suggests a weak short-wave trough will approach eastern SD/MN border by 22/00z. This feature should encourage some increase in the LLJ across IA into southern MN. Strong diurnal heating south of the boundary will ease CINH across the warm sector and scattered storms are expected to develop. Updrafts may initially develop along the cool side of the boundary but with time surface-based updrafts are expected. Hail, wind, and perhaps a few tornadoes can be expected with supercells near the front. ...Four Corners region... Remnants of TS Alberta are progressing west across Mexico as upper ridging builds west into the middle of the CONUS. This flow regime is creating favorable trajectories across the southwestern US for seasonally high PW plume to advance into the Four Corners region. Weak low-latitude short-wave trough over southern CA will eject across the Great Basin which will strengthen mid-level flow across southern UT into southwestern CO. Scattered supercells should develop along the southern fringe of this short wave where strong shear will support organized longer-lived updrafts. Large hail is the primary risk but some tornado risk does exist with this activity. ...Lower Great Lakes to southern New England... Strong boundary-layer heating will once again be noted across the lower Great Lakes region into portions of southern New England. It appears a zone of low-level confluence will extend across the upper OH Valley into southern New England which should help focus scattered convection by peak heating. Gusty winds will be the primary concern with the most robust updrafts. ..Darrow/Wendt.. 06/21/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1243 AM CDT Fri Jun 21 2024 Valid 211200Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE NORTHERN HIGH PLAINS TO THE UPPER MISSISSIPPI VALLEY AND OVER THE FOUR CORNERS REGION... ...SUMMARY... Scattered strong to severe storms are expected from parts of the northern High Plains into the upper Mississippi Valley on Friday. Scattered strong/severe thunderstorms are also possible in the Four Corners vicinity. A few strong storms may also be noted into parts of the lower Great Lakes to southern New England. ...Northern High Plains to the upper Mississippi Valley... Latest water-vapor imagery depicts a low-amplitude short-wave trough over eastern WA/OR. This feature is forecast to shift into the northern Rockies later today. Surface high pressure over MB/SK/Dakotas will ensure southeasterly low-level flow deep into MT ahead of the short wave. 40kt 500mb flow will develop across central MT as the ridge flattens and scattered robust convection should easily develop within a flow regime favorable for supercells. Forecast sounding for central MT exhibit favorable deep-layer shear with strong buoyancy and relatively low cloud bases. Scattered supercells should evolve by early afternoon then propagate southeast along the instability axis toward south-central MT by early evening. Very large hail, gusty winds, and even a few tornadoes can be expected. Downstream across the upper MS Valley, low-level warm advection will focus along a frontal zone that is expected to be draped across WI/southern MN into southeast SD. Latest model guidance suggests a weak short-wave trough will approach eastern SD/MN border by 22/00z. This feature should encourage some increase in the LLJ across IA into southern MN. Strong diurnal heating south of the boundary will ease CINH across the warm sector and scattered storms are expected to develop. Updrafts may initially develop along the cool side of the boundary but with time surface-based updrafts are expected. Hail, wind, and perhaps a few tornadoes can be expected with supercells near the front. ...Four Corners region... Remnants of TS Alberta are progressing west across Mexico as upper ridging builds west into the middle of the CONUS. This flow regime is creating favorable trajectories across the southwestern US for seasonally high PW plume to advance into the Four Corners region. Weak low-latitude short-wave trough over southern CA will eject across the Great Basin which will strengthen mid-level flow across southern UT into southwestern CO. Scattered supercells should develop along the southern fringe of this short wave where strong shear will support organized longer-lived updrafts. Large hail is the primary risk but some tornado risk does exist with this activity. ...Lower Great Lakes to southern New England... Strong boundary-layer heating will once again be noted across the lower Great Lakes region into portions of southern New England. It appears a zone of low-level confluence will extend across the upper OH Valley into southern New England which should help focus scattered convection by peak heating. Gusty winds will be the primary concern with the most robust updrafts. ..Darrow/Wendt.. 06/21/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1243 AM CDT Fri Jun 21 2024 Valid 211200Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE NORTHERN HIGH PLAINS TO THE UPPER MISSISSIPPI VALLEY AND OVER THE FOUR CORNERS REGION... ...SUMMARY... Scattered strong to severe storms are expected from parts of the northern High Plains into the upper Mississippi Valley on Friday. Scattered strong/severe thunderstorms are also possible in the Four Corners vicinity. A few strong storms may also be noted into parts of the lower Great Lakes to southern New England. ...Northern High Plains to the upper Mississippi Valley... Latest water-vapor imagery depicts a low-amplitude short-wave trough over eastern WA/OR. This feature is forecast to shift into the northern Rockies later today. Surface high pressure over MB/SK/Dakotas will ensure southeasterly low-level flow deep into MT ahead of the short wave. 40kt 500mb flow will develop across central MT as the ridge flattens and scattered robust convection should easily develop within a flow regime favorable for supercells. Forecast sounding for central MT exhibit favorable deep-layer shear with strong buoyancy and relatively low cloud bases. Scattered supercells should evolve by early afternoon then propagate southeast along the instability axis toward south-central MT by early evening. Very large hail, gusty winds, and even a few tornadoes can be expected. Downstream across the upper MS Valley, low-level warm advection will focus along a frontal zone that is expected to be draped across WI/southern MN into southeast SD. Latest model guidance suggests a weak short-wave trough will approach eastern SD/MN border by 22/00z. This feature should encourage some increase in the LLJ across IA into southern MN. Strong diurnal heating south of the boundary will ease CINH across the warm sector and scattered storms are expected to develop. Updrafts may initially develop along the cool side of the boundary but with time surface-based updrafts are expected. Hail, wind, and perhaps a few tornadoes can be expected with supercells near the front. ...Four Corners region... Remnants of TS Alberta are progressing west across Mexico as upper ridging builds west into the middle of the CONUS. This flow regime is creating favorable trajectories across the southwestern US for seasonally high PW plume to advance into the Four Corners region. Weak low-latitude short-wave trough over southern CA will eject across the Great Basin which will strengthen mid-level flow across southern UT into southwestern CO. Scattered supercells should develop along the southern fringe of this short wave where strong shear will support organized longer-lived updrafts. Large hail is the primary risk but some tornado risk does exist with this activity. ...Lower Great Lakes to southern New England... Strong boundary-layer heating will once again be noted across the lower Great Lakes region into portions of southern New England. It appears a zone of low-level confluence will extend across the upper OH Valley into southern New England which should help focus scattered convection by peak heating. Gusty winds will be the primary concern with the most robust updrafts. ..Darrow/Wendt.. 06/21/2024 Read more

MD 1351 CONCERNING SEVERE THUNDERSTORM WATCH 440... FOR NORTHEASTERN NEBRASKA...SOUTHEASTERN SOUTH DAKOTA
Mesoscale Discussion 1351 NWS Storm Prediction Center Norman OK 1137 PM CDT Thu Jun 20 2024 Areas affected...northeastern Nebraska...southeastern South Dakota Concerning...Severe Thunderstorm Watch 440... Valid 210437Z - 210600Z The severe weather threat for Severe Thunderstorm Watch 440 continues. SUMMARY...While thunderstorm development is likely to continue across the region overnight, the risk for severe weather is expected to remain limited and a new severe weather watch is not currently anticipated. DISCUSSION...With the approach of the weakening upstream cluster of storms and associated cold pool, the persistent, quasi-stationary supercell near O'Neill has finally accelerated northward and weakened to the north of the surface warm front. Stronger lingering convection within the cluster has been aided by lift along the leading edge of the eastward advancing cold pool, near where it intersects the warm front. However, it appears that this activity will weaken further as it progresses eastward, with renewed convective development possible in its wake, as the nose of a 30-40 kt southerly 850 mb jet remains focused near the O'Neill vicinity. In the presence of modest shear, the newer convective development may grow upscale and organize above the trailing convective outflow overnight. However, with updraft inflow likely to be characterized by rather modest to weak instability, the risk for convection to produce severe hail and wind seems likely to remain low. ..Kerr.. 06/21/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...FSD...OAX...LBF... LAT...LON 43309900 43719740 43479615 42419614 42389724 42179877 42539883 42939888 43309900 Read more

WW 0440 Status Updates
STATUS REPORT ON WW 440 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 5 S BUB TO 45 SE 9V9. REMAINING VALID PORTION OF WW 440 MAY BE ALLOWED TO EXPIRE AT 21/05Z. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 1351. ..KERR..06/21/24 ATTN...WFO...LBF...UNR...FSD... STATUS REPORT FOR WS 440 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS NEC015-071-089-183-210500- NE . NEBRASKA COUNTIES INCLUDED ARE BOYD GARFIELD HOLT WHEELER SDC023-043-210500- SD . SOUTH DAKOTA COUNTIES INCLUDED ARE CHARLES MIX DOUGLAS THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more

WW 440 SEVERE TSTM NE SD 202155Z - 210500Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 440 NWS Storm Prediction Center Norman OK 455 PM CDT Thu Jun 20 2024 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Northern Nebraska Extreme southern South Dakota * Effective this Thursday afternoon from 455 PM until Midnight CDT. * Primary threats include... Scattered large hail and isolated very large hail events to 3.5 inches in diameter possible Scattered damaging wind gusts to 70 mph possible A tornado or two possible SUMMARY...An isolated supercell should persist along a warm front over the northern Sandhills, offering all severe hazards, including a localized tornado threat. In the broader picture, a clustering of severe thunderstorms in the Nebraska Panhandle should move into and across the watch later this evening, posing mainly a hail and severe-wind threat. Isolate severe hail also is possible with later development north of the front. The severe thunderstorm watch area is approximately along and 55 statute miles north and south of a line from 50 miles west of Mullen NE to 15 miles east northeast of Oneill NE. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU0). 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 438...WW 439... AVIATION...A few severe thunderstorms with hail surface and aloft to 3.5 inches. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 550. Mean storm motion vector 26025. ...Edwards Read more

WW 0440 Status Updates
STATUS REPORT ON WW 440 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 15 NW BBW TO 30 ESE ANW TO 40 SSW 9V9. ..KERR..06/21/24 ATTN...WFO...LBF...UNR...FSD... STATUS REPORT FOR WS 440 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS NEC015-071-089-103-115-149-183-210440- NE . NEBRASKA COUNTIES INCLUDED ARE BOYD GARFIELD HOLT KEYA PAHA LOUP ROCK WHEELER SDC023-043-053-210440- SD . SOUTH DAKOTA COUNTIES INCLUDED ARE CHARLES MIX DOUGLAS GREGORY THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more

WW 0440 Status Updates
STATUS REPORT ON WW 440 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 40 SE AIA TO 10 SW MHN TO 35 SW ANW TO 45 NNE VTN. ..WENDT..06/21/24 ATTN...WFO...LBF...UNR...FSD... STATUS REPORT FOR WS 440 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS NEC005-009-015-017-071-089-091-103-113-115-117-149-171-183- 210340- NE . NEBRASKA COUNTIES INCLUDED ARE ARTHUR BLAINE BOYD BROWN GARFIELD HOLT HOOKER KEYA PAHA LOGAN LOUP MCPHERSON ROCK THOMAS WHEELER SDC023-043-053-123-210340- SD . SOUTH DAKOTA COUNTIES INCLUDED ARE CHARLES MIX DOUGLAS GREGORY TRIPP THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES Read more

MD 1350 CONCERNING SEVERE THUNDERSTORM WATCH 440... FOR NORTH-CENTRAL NEBRASKA
Mesoscale Discussion 1350 NWS Storm Prediction Center Norman OK 0835 PM CDT Thu Jun 20 2024 Areas affected...North-central Nebraska Concerning...Severe Thunderstorm Watch 440... Valid 210135Z - 210330Z The severe weather threat for Severe Thunderstorm Watch 440 continues. SUMMARY...The threat of severe gusts will continue this evening with a organized bowing segment in Cherry County moving south-southeast along the warm front. Gusts of 60-75 mph appear possible. DISCUSSION...A bowing segment has developed within Cherry County as a result of linear convection interacting with a supercell. This portion of the convective line is also moving along the warm front in northern Nebraska. With generally low MLCIN inflow (per 00Z LBF sounding), this activity will likely continue south-southeast along the boundary. KLNX velocity data suggest gusts of 60-75 mph are possible. Though the supercell farther east in Holt County has become more disorganized over the last few hours, another surge in the line could occur if they are able to interact later this evening. Severe gusts will the primary hazard along with brief circulations/tornadoes near the warm front. Large-hail potential should remain isolated given convective mode. A watch may be needed east of WW440 should the supercell in Holt County maintains its intensity. ..Wendt.. 06/21/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...OAX...LBF...UNR... LAT...LON 42880107 43000069 42559852 42389818 42009829 41909958 42040074 42190125 42880107 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0740 PM CDT Thu Jun 20 2024 Valid 210100Z - 211200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTHERN NEW ENGLAND AND THE CENTRAL HIGH PLAINS... ...SUMMARY... Scattered damaging gusts are expected this evening across southern New England. Scattered severe storms are also expected over parts of the north-central High Plains. ...01z Update... A southward-propagating MCS has evolved over southern New England, along the southern fringe of stronger westerlies. This activity developed well ahead of the main cold front, along a prefrontal low-level confluence zone, and is advancing steadily south across MA at this time. Surface temperatures remain quite warm across this region with readings holding in the 80s to near 90F. It appears adequate buoyancy is holding across interior southern New England such that this complex should move of the coast with an attendant risk for locally damaging winds. Weak mid-level disturbance is shifting east across the central High Plains this evening. A substantial complex of storms has evolved ahead of this feature, extending from northeast CO-NE Panhandle-south-central SD. While this activity has produced very large hail earlier in its convective cycle, a bowing squall line has emerged over Cherry County NE, and this portion of the MCS may generate severe winds as it surges east within a focused warm-advection zone. LLJ will increase markedly across the central Plains over the next few hours, supporting forward propagation toward southeast SD late this evening. ..Darrow.. 06/21/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0740 PM CDT Thu Jun 20 2024 Valid 210100Z - 211200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTHERN NEW ENGLAND AND THE CENTRAL HIGH PLAINS... ...SUMMARY... Scattered damaging gusts are expected this evening across southern New England. Scattered severe storms are also expected over parts of the north-central High Plains. ...01z Update... A southward-propagating MCS has evolved over southern New England, along the southern fringe of stronger westerlies. This activity developed well ahead of the main cold front, along a prefrontal low-level confluence zone, and is advancing steadily south across MA at this time. Surface temperatures remain quite warm across this region with readings holding in the 80s to near 90F. It appears adequate buoyancy is holding across interior southern New England such that this complex should move of the coast with an attendant risk for locally damaging winds. Weak mid-level disturbance is shifting east across the central High Plains this evening. A substantial complex of storms has evolved ahead of this feature, extending from northeast CO-NE Panhandle-south-central SD. While this activity has produced very large hail earlier in its convective cycle, a bowing squall line has emerged over Cherry County NE, and this portion of the MCS may generate severe winds as it surges east within a focused warm-advection zone. LLJ will increase markedly across the central Plains over the next few hours, supporting forward propagation toward southeast SD late this evening. ..Darrow.. 06/21/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0740 PM CDT Thu Jun 20 2024 Valid 210100Z - 211200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTHERN NEW ENGLAND AND THE CENTRAL HIGH PLAINS... ...SUMMARY... Scattered damaging gusts are expected this evening across southern New England. Scattered severe storms are also expected over parts of the north-central High Plains. ...01z Update... A southward-propagating MCS has evolved over southern New England, along the southern fringe of stronger westerlies. This activity developed well ahead of the main cold front, along a prefrontal low-level confluence zone, and is advancing steadily south across MA at this time. Surface temperatures remain quite warm across this region with readings holding in the 80s to near 90F. It appears adequate buoyancy is holding across interior southern New England such that this complex should move of the coast with an attendant risk for locally damaging winds. Weak mid-level disturbance is shifting east across the central High Plains this evening. A substantial complex of storms has evolved ahead of this feature, extending from northeast CO-NE Panhandle-south-central SD. While this activity has produced very large hail earlier in its convective cycle, a bowing squall line has emerged over Cherry County NE, and this portion of the MCS may generate severe winds as it surges east within a focused warm-advection zone. LLJ will increase markedly across the central Plains over the next few hours, supporting forward propagation toward southeast SD late this evening. ..Darrow.. 06/21/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0740 PM CDT Thu Jun 20 2024 Valid 210100Z - 211200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTHERN NEW ENGLAND AND THE CENTRAL HIGH PLAINS... ...SUMMARY... Scattered damaging gusts are expected this evening across southern New England. Scattered severe storms are also expected over parts of the north-central High Plains. ...01z Update... A southward-propagating MCS has evolved over southern New England, along the southern fringe of stronger westerlies. This activity developed well ahead of the main cold front, along a prefrontal low-level confluence zone, and is advancing steadily south across MA at this time. Surface temperatures remain quite warm across this region with readings holding in the 80s to near 90F. It appears adequate buoyancy is holding across interior southern New England such that this complex should move of the coast with an attendant risk for locally damaging winds. Weak mid-level disturbance is shifting east across the central High Plains this evening. A substantial complex of storms has evolved ahead of this feature, extending from northeast CO-NE Panhandle-south-central SD. While this activity has produced very large hail earlier in its convective cycle, a bowing squall line has emerged over Cherry County NE, and this portion of the MCS may generate severe winds as it surges east within a focused warm-advection zone. LLJ will increase markedly across the central Plains over the next few hours, supporting forward propagation toward southeast SD late this evening. ..Darrow.. 06/21/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0740 PM CDT Thu Jun 20 2024 Valid 210100Z - 211200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTHERN NEW ENGLAND AND THE CENTRAL HIGH PLAINS... ...SUMMARY... Scattered damaging gusts are expected this evening across southern New England. Scattered severe storms are also expected over parts of the north-central High Plains. ...01z Update... A southward-propagating MCS has evolved over southern New England, along the southern fringe of stronger westerlies. This activity developed well ahead of the main cold front, along a prefrontal low-level confluence zone, and is advancing steadily south across MA at this time. Surface temperatures remain quite warm across this region with readings holding in the 80s to near 90F. It appears adequate buoyancy is holding across interior southern New England such that this complex should move of the coast with an attendant risk for locally damaging winds. Weak mid-level disturbance is shifting east across the central High Plains this evening. A substantial complex of storms has evolved ahead of this feature, extending from northeast CO-NE Panhandle-south-central SD. While this activity has produced very large hail earlier in its convective cycle, a bowing squall line has emerged over Cherry County NE, and this portion of the MCS may generate severe winds as it surges east within a focused warm-advection zone. LLJ will increase markedly across the central Plains over the next few hours, supporting forward propagation toward southeast SD late this evening. ..Darrow.. 06/21/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0740 PM CDT Thu Jun 20 2024 Valid 210100Z - 211200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTHERN NEW ENGLAND AND THE CENTRAL HIGH PLAINS... ...SUMMARY... Scattered damaging gusts are expected this evening across southern New England. Scattered severe storms are also expected over parts of the north-central High Plains. ...01z Update... A southward-propagating MCS has evolved over southern New England, along the southern fringe of stronger westerlies. This activity developed well ahead of the main cold front, along a prefrontal low-level confluence zone, and is advancing steadily south across MA at this time. Surface temperatures remain quite warm across this region with readings holding in the 80s to near 90F. It appears adequate buoyancy is holding across interior southern New England such that this complex should move of the coast with an attendant risk for locally damaging winds. Weak mid-level disturbance is shifting east across the central High Plains this evening. A substantial complex of storms has evolved ahead of this feature, extending from northeast CO-NE Panhandle-south-central SD. While this activity has produced very large hail earlier in its convective cycle, a bowing squall line has emerged over Cherry County NE, and this portion of the MCS may generate severe winds as it surges east within a focused warm-advection zone. LLJ will increase markedly across the central Plains over the next few hours, supporting forward propagation toward southeast SD late this evening. ..Darrow.. 06/21/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0740 PM CDT Thu Jun 20 2024 Valid 210100Z - 211200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTHERN NEW ENGLAND AND THE CENTRAL HIGH PLAINS... ...SUMMARY... Scattered damaging gusts are expected this evening across southern New England. Scattered severe storms are also expected over parts of the north-central High Plains. ...01z Update... A southward-propagating MCS has evolved over southern New England, along the southern fringe of stronger westerlies. This activity developed well ahead of the main cold front, along a prefrontal low-level confluence zone, and is advancing steadily south across MA at this time. Surface temperatures remain quite warm across this region with readings holding in the 80s to near 90F. It appears adequate buoyancy is holding across interior southern New England such that this complex should move of the coast with an attendant risk for locally damaging winds. Weak mid-level disturbance is shifting east across the central High Plains this evening. A substantial complex of storms has evolved ahead of this feature, extending from northeast CO-NE Panhandle-south-central SD. While this activity has produced very large hail earlier in its convective cycle, a bowing squall line has emerged over Cherry County NE, and this portion of the MCS may generate severe winds as it surges east within a focused warm-advection zone. LLJ will increase markedly across the central Plains over the next few hours, supporting forward propagation toward southeast SD late this evening. ..Darrow.. 06/21/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0740 PM CDT Thu Jun 20 2024 Valid 210100Z - 211200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTHERN NEW ENGLAND AND THE CENTRAL HIGH PLAINS... ...SUMMARY... Scattered damaging gusts are expected this evening across southern New England. Scattered severe storms are also expected over parts of the north-central High Plains. ...01z Update... A southward-propagating MCS has evolved over southern New England, along the southern fringe of stronger westerlies. This activity developed well ahead of the main cold front, along a prefrontal low-level confluence zone, and is advancing steadily south across MA at this time. Surface temperatures remain quite warm across this region with readings holding in the 80s to near 90F. It appears adequate buoyancy is holding across interior southern New England such that this complex should move of the coast with an attendant risk for locally damaging winds. Weak mid-level disturbance is shifting east across the central High Plains this evening. A substantial complex of storms has evolved ahead of this feature, extending from northeast CO-NE Panhandle-south-central SD. While this activity has produced very large hail earlier in its convective cycle, a bowing squall line has emerged over Cherry County NE, and this portion of the MCS may generate severe winds as it surges east within a focused warm-advection zone. LLJ will increase markedly across the central Plains over the next few hours, supporting forward propagation toward southeast SD late this evening. ..Darrow.. 06/21/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0740 PM CDT Thu Jun 20 2024 Valid 210100Z - 211200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTHERN NEW ENGLAND AND THE CENTRAL HIGH PLAINS... ...SUMMARY... Scattered damaging gusts are expected this evening across southern New England. Scattered severe storms are also expected over parts of the north-central High Plains. ...01z Update... A southward-propagating MCS has evolved over southern New England, along the southern fringe of stronger westerlies. This activity developed well ahead of the main cold front, along a prefrontal low-level confluence zone, and is advancing steadily south across MA at this time. Surface temperatures remain quite warm across this region with readings holding in the 80s to near 90F. It appears adequate buoyancy is holding across interior southern New England such that this complex should move of the coast with an attendant risk for locally damaging winds. Weak mid-level disturbance is shifting east across the central High Plains this evening. A substantial complex of storms has evolved ahead of this feature, extending from northeast CO-NE Panhandle-south-central SD. While this activity has produced very large hail earlier in its convective cycle, a bowing squall line has emerged over Cherry County NE, and this portion of the MCS may generate severe winds as it surges east within a focused warm-advection zone. LLJ will increase markedly across the central Plains over the next few hours, supporting forward propagation toward southeast SD late this evening. ..Darrow.. 06/21/2024 Read more

MD 1349 CONCERNING SEVERE THUNDERSTORM WATCH 440... FOR WESTERN INTO CENTRAL NEBRASKA
Mesoscale Discussion 1349 NWS Storm Prediction Center Norman OK 0633 PM CDT Thu Jun 20 2024 Areas affected...Western into central Nebraska Concerning...Severe Thunderstorm Watch 440... Valid 202333Z - 210100Z The severe weather threat for Severe Thunderstorm Watch 440 continues. SUMMARY...Severe winds will generally become the predominant threat in western/central Nebraska with time as an MCS moves east. Storms favorably interacting with the warm front, particularly those of discrete mode, will still pose some risk of a tornado and large hail. DISCUSSION...Storms continue to grow upscale into an MCS in western Nebraska. Severe winds will likely be on the increase with this activity--the Alliance, NE ASOS recently recorded a 70 kt gust. Temperatures ahead of this line of storms remain in the upper 80s to low 90s F and the low-level jet should increase over the next few hours, aiding in storm maintenance. Along the warm front, more discrete storms in northwest Cherry County and east of Ainsworth continue. These storms will pose the greatest risk for large hail and possibly a tornado should they interact favorably with the warm front. The storm east of Ainsworth produced one reported tornado so far. The storm has become more HP/messy in character; however, the mesocyclone has periodically intensified over the last couple of hours as well. ..Wendt.. 06/20/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LBF...CYS... LAT...LON 41720309 42130281 42810268 42960082 42589928 42239893 42129931 42240058 41810156 41610247 41720309 Read more

WW 0440 Status Updates
STATUS REPORT ON WW 440 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 30 E AIA TO 45 WNW MHN TO 60 NW MHN TO 40 WNW VTN TO 45 SSE PHP. ..WENDT..06/21/24 ATTN...WFO...LBF...UNR...FSD... STATUS REPORT FOR WS 440 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS NEC005-009-015-017-031-071-075-089-091-103-113-115-117-149-171- 183-210140- NE . NEBRASKA COUNTIES INCLUDED ARE ARTHUR BLAINE BOYD BROWN CHERRY GARFIELD GRANT HOLT HOOKER KEYA PAHA LOGAN LOUP MCPHERSON ROCK THOMAS WHEELER SDC023-043-053-121-123-210140- SD . SOUTH DAKOTA COUNTIES INCLUDED ARE CHARLES MIX DOUGLAS GREGORY TODD TRIPP THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL Read more