Severe Storms

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0203 AM CDT Sat Jun 28 2025 Valid 281200Z - 291200Z ...Synopsis... Subtle mid-level troughing on the northern periphery of the sub tropical ridge will continue over the northern Rockies and Northwest today. A belt of stronger mid-level flow will remain in place over parts of the Intermountain West, supporting dry downslope flow ahead of a weak cold front over the Northwest. Lee troughing and the increased flow aloft will encourage breezy westerly flow amid dry conditions, conducive for elevated fire-weather conditions. ...Snake River Plain into western WY... Increasing mid-level flow attendant to a passing mid-level shortwave trough will overspread a dry and well-mixed boundary layer across portions of ID and western WY this afternoon. Aided by lee troughing, elevated surface winds are expected across the central/eastern portions of the Snake River Plain and through the Red Desert in southwest WY. Westerly winds of 15-20 mph, combined with warm afternoon temperatures and relative humidity in the 15-20 percent range, will support elevated fire weather conditions this afternoon and evening. ..Lyons.. 06/28/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0203 AM CDT Sat Jun 28 2025 Valid 281200Z - 291200Z ...Synopsis... Subtle mid-level troughing on the northern periphery of the sub tropical ridge will continue over the northern Rockies and Northwest today. A belt of stronger mid-level flow will remain in place over parts of the Intermountain West, supporting dry downslope flow ahead of a weak cold front over the Northwest. Lee troughing and the increased flow aloft will encourage breezy westerly flow amid dry conditions, conducive for elevated fire-weather conditions. ...Snake River Plain into western WY... Increasing mid-level flow attendant to a passing mid-level shortwave trough will overspread a dry and well-mixed boundary layer across portions of ID and western WY this afternoon. Aided by lee troughing, elevated surface winds are expected across the central/eastern portions of the Snake River Plain and through the Red Desert in southwest WY. Westerly winds of 15-20 mph, combined with warm afternoon temperatures and relative humidity in the 15-20 percent range, will support elevated fire weather conditions this afternoon and evening. ..Lyons.. 06/28/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0203 AM CDT Sat Jun 28 2025 Valid 281200Z - 291200Z ...Synopsis... Subtle mid-level troughing on the northern periphery of the sub tropical ridge will continue over the northern Rockies and Northwest today. A belt of stronger mid-level flow will remain in place over parts of the Intermountain West, supporting dry downslope flow ahead of a weak cold front over the Northwest. Lee troughing and the increased flow aloft will encourage breezy westerly flow amid dry conditions, conducive for elevated fire-weather conditions. ...Snake River Plain into western WY... Increasing mid-level flow attendant to a passing mid-level shortwave trough will overspread a dry and well-mixed boundary layer across portions of ID and western WY this afternoon. Aided by lee troughing, elevated surface winds are expected across the central/eastern portions of the Snake River Plain and through the Red Desert in southwest WY. Westerly winds of 15-20 mph, combined with warm afternoon temperatures and relative humidity in the 15-20 percent range, will support elevated fire weather conditions this afternoon and evening. ..Lyons.. 06/28/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

MD 1487 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR SOUTHEAST NORTH DAKOTA...WESTERN MINNESOTA...NORTHEAST SOUTH DAKOTA
Mesoscale Discussion 1487 NWS Storm Prediction Center Norman OK 1247 AM CDT Sat Jun 28 2025 Areas affected...Southeast North Dakota...Western Minnesota...Northeast South Dakota Concerning...Severe potential...Watch unlikely Valid 280547Z - 280645Z Probability of Watch Issuance...20 percent SUMMARY...A lingering isolated severe threat is expected over the next few hours from southeast North Dakota into northeast South Dakota and western Minnesota. A few severe gusts and hail will be the primary threats. The severe threat is expected to become increasingly marginal, and WW 468 will be allowed to expire at 0600Z. DISCUSSION...The latest hi-resolution radar imagery from KMVX shows a cluster of strong thunderstorms, with a few embedded potentially severe cells. These storms are located to the northeast of a 1006 mb low, along the eastern edge of strong instability where the RAP has MLCAPE in the 2000 to 3000 J/kg range. A shortwave trough, evident on water vapor imagery, along with warm advection will provide support for continued convective development over the next few hours. Overnight RAP forecast soundings have effective shear near 40 knots with mid-level lapse rates between 7 and 8 C/km. This should support an isolated severe threat with potential for a few severe gusts and hail. However, a capping inversion is forecast to gradually increase, which combined with weakening instability, should result in the severe threat becoming more marginal with time. ..Broyles/Smith.. 06/28/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...MPX...FGF...ABR...BIS... LAT...LON 47319604 47059562 46579531 45989532 45509567 45339647 45419852 45609932 45899963 46329977 46749964 47099940 47369882 47449730 47409653 47319604 MOST PROBABLE PEAK WIND GUST...55-70 MPH MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN Read more

MD 1486 CONCERNING SEVERE THUNDERSTORM WATCH 470... FOR SOUTHEAST SOUTH DAKOTA...NORTHEAST NEBRASKA AND NORTHWEST IOWA
Mesoscale Discussion 1486 NWS Storm Prediction Center Norman OK 1147 PM CDT Fri Jun 27 2025 Areas affected...Southeast South Dakota...northeast Nebraska and northwest Iowa Concerning...Severe Thunderstorm Watch 470... Valid 280447Z - 280615Z The severe weather threat for Severe Thunderstorm Watch 470 continues. SUMMARY...The threat for damaging winds has likely peaked already and the storms may begin a slow weakening trend through 06-07z. DISCUSSION...The bowing cluster with a history of severe outflow gusts up to 83 mph is now showing the initial signs of weakening. An increase in convective inhibition and weakening deep-layer vertical shear with southeastward extent appear to be contributing to weakening of the cluster, as evidenced by lowering echo tops and a fine line/outflow progressing ahead of the main updrafts. This weakening trend is likely to continue and the storms should weaken by 06-07z, though isolated strong-severe outflow gusts may occur in the interim. ..Thompson.. 06/28/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...FSD...OAX... LAT...LON 42399606 42519722 42769741 43399678 43239582 42729577 42399606 MOST PROBABLE PEAK WIND GUST...55-70 MPH MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1257 AM CDT Sat Jun 28 2025 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM CENTRAL IOWA INTO THE WESTERN UPPER PENINSULA OF MICHIGAN.... ...SUMMARY... Scattered strong to severe storms appear possible Sunday from the central Great Plains into the upper Great Lakes region, with at least some potential for the evolution of a large, organized severe storm cluster across parts of the mid into lower Missouri Valley and central Great Plains late Sunday through Sunday night. ...Synopsis... A mid-level trough will amplify across the northern Plains on Sunday. At the surface, a cold front will advance slowly east across the northern Plains and Upper Midwest. ...Central Plains to the Upper Midwest... Very strong to potentially extreme instability is forecast from the central Plains to the Upper Midwest on Sunday. Weak tropospheric flow is forecast across much of Nebraska, Kansas, and Missouri on Sunday. This should limit storm organization with only isolated/widely scattered severe wind gusts possible within this large zone of marginal risk. Mid-level flow is forecast to be somewhat stronger across northern Iowa, but still relatively weak. This may result in slightly more organized convection where very strong to extreme instability is also present. Therefore, the slight risk was expanded south to cover this threat, particularly since scattered to widespread storm coverage is anticipated. Instability will not be as strong farther north across Wisconsin, but stronger mid-level flow (30-35 knots) will be present, which may result in a few rotating updrafts and/or bowing line segments capable of isolated large hail and severe wind gusts. ...Mid-Atlantic... Moderate to strong instability is forecast to develop across portions of the Mid-Atlantic on Sunday. A very moist environment will be in place with PWAT values over 2 inches and dewpoints in the mid 70s. Therefore, wet microburts will be possible with the strongest storms which develop Sunday afternoon/evening. ..Bentley.. 06/28/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1257 AM CDT Sat Jun 28 2025 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM CENTRAL IOWA INTO THE WESTERN UPPER PENINSULA OF MICHIGAN.... ...SUMMARY... Scattered strong to severe storms appear possible Sunday from the central Great Plains into the upper Great Lakes region, with at least some potential for the evolution of a large, organized severe storm cluster across parts of the mid into lower Missouri Valley and central Great Plains late Sunday through Sunday night. ...Synopsis... A mid-level trough will amplify across the northern Plains on Sunday. At the surface, a cold front will advance slowly east across the northern Plains and Upper Midwest. ...Central Plains to the Upper Midwest... Very strong to potentially extreme instability is forecast from the central Plains to the Upper Midwest on Sunday. Weak tropospheric flow is forecast across much of Nebraska, Kansas, and Missouri on Sunday. This should limit storm organization with only isolated/widely scattered severe wind gusts possible within this large zone of marginal risk. Mid-level flow is forecast to be somewhat stronger across northern Iowa, but still relatively weak. This may result in slightly more organized convection where very strong to extreme instability is also present. Therefore, the slight risk was expanded south to cover this threat, particularly since scattered to widespread storm coverage is anticipated. Instability will not be as strong farther north across Wisconsin, but stronger mid-level flow (30-35 knots) will be present, which may result in a few rotating updrafts and/or bowing line segments capable of isolated large hail and severe wind gusts. ...Mid-Atlantic... Moderate to strong instability is forecast to develop across portions of the Mid-Atlantic on Sunday. A very moist environment will be in place with PWAT values over 2 inches and dewpoints in the mid 70s. Therefore, wet microburts will be possible with the strongest storms which develop Sunday afternoon/evening. ..Bentley.. 06/28/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1257 AM CDT Sat Jun 28 2025 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM CENTRAL IOWA INTO THE WESTERN UPPER PENINSULA OF MICHIGAN.... ...SUMMARY... Scattered strong to severe storms appear possible Sunday from the central Great Plains into the upper Great Lakes region, with at least some potential for the evolution of a large, organized severe storm cluster across parts of the mid into lower Missouri Valley and central Great Plains late Sunday through Sunday night. ...Synopsis... A mid-level trough will amplify across the northern Plains on Sunday. At the surface, a cold front will advance slowly east across the northern Plains and Upper Midwest. ...Central Plains to the Upper Midwest... Very strong to potentially extreme instability is forecast from the central Plains to the Upper Midwest on Sunday. Weak tropospheric flow is forecast across much of Nebraska, Kansas, and Missouri on Sunday. This should limit storm organization with only isolated/widely scattered severe wind gusts possible within this large zone of marginal risk. Mid-level flow is forecast to be somewhat stronger across northern Iowa, but still relatively weak. This may result in slightly more organized convection where very strong to extreme instability is also present. Therefore, the slight risk was expanded south to cover this threat, particularly since scattered to widespread storm coverage is anticipated. Instability will not be as strong farther north across Wisconsin, but stronger mid-level flow (30-35 knots) will be present, which may result in a few rotating updrafts and/or bowing line segments capable of isolated large hail and severe wind gusts. ...Mid-Atlantic... Moderate to strong instability is forecast to develop across portions of the Mid-Atlantic on Sunday. A very moist environment will be in place with PWAT values over 2 inches and dewpoints in the mid 70s. Therefore, wet microburts will be possible with the strongest storms which develop Sunday afternoon/evening. ..Bentley.. 06/28/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1257 AM CDT Sat Jun 28 2025 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM CENTRAL IOWA INTO THE WESTERN UPPER PENINSULA OF MICHIGAN.... ...SUMMARY... Scattered strong to severe storms appear possible Sunday from the central Great Plains into the upper Great Lakes region, with at least some potential for the evolution of a large, organized severe storm cluster across parts of the mid into lower Missouri Valley and central Great Plains late Sunday through Sunday night. ...Synopsis... A mid-level trough will amplify across the northern Plains on Sunday. At the surface, a cold front will advance slowly east across the northern Plains and Upper Midwest. ...Central Plains to the Upper Midwest... Very strong to potentially extreme instability is forecast from the central Plains to the Upper Midwest on Sunday. Weak tropospheric flow is forecast across much of Nebraska, Kansas, and Missouri on Sunday. This should limit storm organization with only isolated/widely scattered severe wind gusts possible within this large zone of marginal risk. Mid-level flow is forecast to be somewhat stronger across northern Iowa, but still relatively weak. This may result in slightly more organized convection where very strong to extreme instability is also present. Therefore, the slight risk was expanded south to cover this threat, particularly since scattered to widespread storm coverage is anticipated. Instability will not be as strong farther north across Wisconsin, but stronger mid-level flow (30-35 knots) will be present, which may result in a few rotating updrafts and/or bowing line segments capable of isolated large hail and severe wind gusts. ...Mid-Atlantic... Moderate to strong instability is forecast to develop across portions of the Mid-Atlantic on Sunday. A very moist environment will be in place with PWAT values over 2 inches and dewpoints in the mid 70s. Therefore, wet microburts will be possible with the strongest storms which develop Sunday afternoon/evening. ..Bentley.. 06/28/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1257 AM CDT Sat Jun 28 2025 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM CENTRAL IOWA INTO THE WESTERN UPPER PENINSULA OF MICHIGAN.... ...SUMMARY... Scattered strong to severe storms appear possible Sunday from the central Great Plains into the upper Great Lakes region, with at least some potential for the evolution of a large, organized severe storm cluster across parts of the mid into lower Missouri Valley and central Great Plains late Sunday through Sunday night. ...Synopsis... A mid-level trough will amplify across the northern Plains on Sunday. At the surface, a cold front will advance slowly east across the northern Plains and Upper Midwest. ...Central Plains to the Upper Midwest... Very strong to potentially extreme instability is forecast from the central Plains to the Upper Midwest on Sunday. Weak tropospheric flow is forecast across much of Nebraska, Kansas, and Missouri on Sunday. This should limit storm organization with only isolated/widely scattered severe wind gusts possible within this large zone of marginal risk. Mid-level flow is forecast to be somewhat stronger across northern Iowa, but still relatively weak. This may result in slightly more organized convection where very strong to extreme instability is also present. Therefore, the slight risk was expanded south to cover this threat, particularly since scattered to widespread storm coverage is anticipated. Instability will not be as strong farther north across Wisconsin, but stronger mid-level flow (30-35 knots) will be present, which may result in a few rotating updrafts and/or bowing line segments capable of isolated large hail and severe wind gusts. ...Mid-Atlantic... Moderate to strong instability is forecast to develop across portions of the Mid-Atlantic on Sunday. A very moist environment will be in place with PWAT values over 2 inches and dewpoints in the mid 70s. Therefore, wet microburts will be possible with the strongest storms which develop Sunday afternoon/evening. ..Bentley.. 06/28/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1257 AM CDT Sat Jun 28 2025 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM CENTRAL IOWA INTO THE WESTERN UPPER PENINSULA OF MICHIGAN.... ...SUMMARY... Scattered strong to severe storms appear possible Sunday from the central Great Plains into the upper Great Lakes region, with at least some potential for the evolution of a large, organized severe storm cluster across parts of the mid into lower Missouri Valley and central Great Plains late Sunday through Sunday night. ...Synopsis... A mid-level trough will amplify across the northern Plains on Sunday. At the surface, a cold front will advance slowly east across the northern Plains and Upper Midwest. ...Central Plains to the Upper Midwest... Very strong to potentially extreme instability is forecast from the central Plains to the Upper Midwest on Sunday. Weak tropospheric flow is forecast across much of Nebraska, Kansas, and Missouri on Sunday. This should limit storm organization with only isolated/widely scattered severe wind gusts possible within this large zone of marginal risk. Mid-level flow is forecast to be somewhat stronger across northern Iowa, but still relatively weak. This may result in slightly more organized convection where very strong to extreme instability is also present. Therefore, the slight risk was expanded south to cover this threat, particularly since scattered to widespread storm coverage is anticipated. Instability will not be as strong farther north across Wisconsin, but stronger mid-level flow (30-35 knots) will be present, which may result in a few rotating updrafts and/or bowing line segments capable of isolated large hail and severe wind gusts. ...Mid-Atlantic... Moderate to strong instability is forecast to develop across portions of the Mid-Atlantic on Sunday. A very moist environment will be in place with PWAT values over 2 inches and dewpoints in the mid 70s. Therefore, wet microburts will be possible with the strongest storms which develop Sunday afternoon/evening. ..Bentley.. 06/28/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1257 AM CDT Sat Jun 28 2025 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM CENTRAL IOWA INTO THE WESTERN UPPER PENINSULA OF MICHIGAN.... ...SUMMARY... Scattered strong to severe storms appear possible Sunday from the central Great Plains into the upper Great Lakes region, with at least some potential for the evolution of a large, organized severe storm cluster across parts of the mid into lower Missouri Valley and central Great Plains late Sunday through Sunday night. ...Synopsis... A mid-level trough will amplify across the northern Plains on Sunday. At the surface, a cold front will advance slowly east across the northern Plains and Upper Midwest. ...Central Plains to the Upper Midwest... Very strong to potentially extreme instability is forecast from the central Plains to the Upper Midwest on Sunday. Weak tropospheric flow is forecast across much of Nebraska, Kansas, and Missouri on Sunday. This should limit storm organization with only isolated/widely scattered severe wind gusts possible within this large zone of marginal risk. Mid-level flow is forecast to be somewhat stronger across northern Iowa, but still relatively weak. This may result in slightly more organized convection where very strong to extreme instability is also present. Therefore, the slight risk was expanded south to cover this threat, particularly since scattered to widespread storm coverage is anticipated. Instability will not be as strong farther north across Wisconsin, but stronger mid-level flow (30-35 knots) will be present, which may result in a few rotating updrafts and/or bowing line segments capable of isolated large hail and severe wind gusts. ...Mid-Atlantic... Moderate to strong instability is forecast to develop across portions of the Mid-Atlantic on Sunday. A very moist environment will be in place with PWAT values over 2 inches and dewpoints in the mid 70s. Therefore, wet microburts will be possible with the strongest storms which develop Sunday afternoon/evening. ..Bentley.. 06/28/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1257 AM CDT Sat Jun 28 2025 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM CENTRAL IOWA INTO THE WESTERN UPPER PENINSULA OF MICHIGAN.... ...SUMMARY... Scattered strong to severe storms appear possible Sunday from the central Great Plains into the upper Great Lakes region, with at least some potential for the evolution of a large, organized severe storm cluster across parts of the mid into lower Missouri Valley and central Great Plains late Sunday through Sunday night. ...Synopsis... A mid-level trough will amplify across the northern Plains on Sunday. At the surface, a cold front will advance slowly east across the northern Plains and Upper Midwest. ...Central Plains to the Upper Midwest... Very strong to potentially extreme instability is forecast from the central Plains to the Upper Midwest on Sunday. Weak tropospheric flow is forecast across much of Nebraska, Kansas, and Missouri on Sunday. This should limit storm organization with only isolated/widely scattered severe wind gusts possible within this large zone of marginal risk. Mid-level flow is forecast to be somewhat stronger across northern Iowa, but still relatively weak. This may result in slightly more organized convection where very strong to extreme instability is also present. Therefore, the slight risk was expanded south to cover this threat, particularly since scattered to widespread storm coverage is anticipated. Instability will not be as strong farther north across Wisconsin, but stronger mid-level flow (30-35 knots) will be present, which may result in a few rotating updrafts and/or bowing line segments capable of isolated large hail and severe wind gusts. ...Mid-Atlantic... Moderate to strong instability is forecast to develop across portions of the Mid-Atlantic on Sunday. A very moist environment will be in place with PWAT values over 2 inches and dewpoints in the mid 70s. Therefore, wet microburts will be possible with the strongest storms which develop Sunday afternoon/evening. ..Bentley.. 06/28/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1257 AM CDT Sat Jun 28 2025 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM CENTRAL IOWA INTO THE WESTERN UPPER PENINSULA OF MICHIGAN.... ...SUMMARY... Scattered strong to severe storms appear possible Sunday from the central Great Plains into the upper Great Lakes region, with at least some potential for the evolution of a large, organized severe storm cluster across parts of the mid into lower Missouri Valley and central Great Plains late Sunday through Sunday night. ...Synopsis... A mid-level trough will amplify across the northern Plains on Sunday. At the surface, a cold front will advance slowly east across the northern Plains and Upper Midwest. ...Central Plains to the Upper Midwest... Very strong to potentially extreme instability is forecast from the central Plains to the Upper Midwest on Sunday. Weak tropospheric flow is forecast across much of Nebraska, Kansas, and Missouri on Sunday. This should limit storm organization with only isolated/widely scattered severe wind gusts possible within this large zone of marginal risk. Mid-level flow is forecast to be somewhat stronger across northern Iowa, but still relatively weak. This may result in slightly more organized convection where very strong to extreme instability is also present. Therefore, the slight risk was expanded south to cover this threat, particularly since scattered to widespread storm coverage is anticipated. Instability will not be as strong farther north across Wisconsin, but stronger mid-level flow (30-35 knots) will be present, which may result in a few rotating updrafts and/or bowing line segments capable of isolated large hail and severe wind gusts. ...Mid-Atlantic... Moderate to strong instability is forecast to develop across portions of the Mid-Atlantic on Sunday. A very moist environment will be in place with PWAT values over 2 inches and dewpoints in the mid 70s. Therefore, wet microburts will be possible with the strongest storms which develop Sunday afternoon/evening. ..Bentley.. 06/28/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1257 AM CDT Sat Jun 28 2025 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM CENTRAL IOWA INTO THE WESTERN UPPER PENINSULA OF MICHIGAN.... ...SUMMARY... Scattered strong to severe storms appear possible Sunday from the central Great Plains into the upper Great Lakes region, with at least some potential for the evolution of a large, organized severe storm cluster across parts of the mid into lower Missouri Valley and central Great Plains late Sunday through Sunday night. ...Synopsis... A mid-level trough will amplify across the northern Plains on Sunday. At the surface, a cold front will advance slowly east across the northern Plains and Upper Midwest. ...Central Plains to the Upper Midwest... Very strong to potentially extreme instability is forecast from the central Plains to the Upper Midwest on Sunday. Weak tropospheric flow is forecast across much of Nebraska, Kansas, and Missouri on Sunday. This should limit storm organization with only isolated/widely scattered severe wind gusts possible within this large zone of marginal risk. Mid-level flow is forecast to be somewhat stronger across northern Iowa, but still relatively weak. This may result in slightly more organized convection where very strong to extreme instability is also present. Therefore, the slight risk was expanded south to cover this threat, particularly since scattered to widespread storm coverage is anticipated. Instability will not be as strong farther north across Wisconsin, but stronger mid-level flow (30-35 knots) will be present, which may result in a few rotating updrafts and/or bowing line segments capable of isolated large hail and severe wind gusts. ...Mid-Atlantic... Moderate to strong instability is forecast to develop across portions of the Mid-Atlantic on Sunday. A very moist environment will be in place with PWAT values over 2 inches and dewpoints in the mid 70s. Therefore, wet microburts will be possible with the strongest storms which develop Sunday afternoon/evening. ..Bentley.. 06/28/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1241 AM CDT Sat Jun 28 2025 Valid 281200Z - 291200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE UPPER MIDWEST TO THE BLACK HILLS REGION... ...SUMMARY... Scattered strong to severe thunderstorms, perhaps including one or two organizing clusters, will pose a risk for severe hail, wind and perhaps a couple of tornadoes across parts of the Upper Midwest into the Plains of South Dakota and Nebraska. ...Upper Midwest to the Black Hills of South Dakota... Seasonally typical early summer pattern will be noted today as stronger westerlies are confined to the northern U.S., and much weaker flow is observed across the southern two-thirds of the CONUS. Latest water-vapor imagery suggests a few weak disturbances are translating across the northern Rockies toward the northern Plains and this will shunt the primary synoptic boundary across much of the Dakotas into the upper MS Valley by early evening. This boundary will prove instrumental in focusing deep convection during the afternoon/evening hours. Early this morning, scattered clusters of strong/severe thunderstorms are propagating southeast across the eastern Dakotas. This activity will advance into the upper MS Valley early in the period as LLJ focuses across eastern SD into northern MN. While some severe threat will be noted with a possible MCS at daybreak, convective outflow will largely influence subsequent regeneration. Latest model guidance suggests an east-west boundary will drape itself across western WI/southern MN by 18z, likely modified by the aforementioned early-day MCS. Boundary-layer heating is expected to aid buoyancy across the Dakotas southeast of the cold front, and scattered thunderstorms should readily develop along this wind shift by late afternoon, aided in part by a weak short wave trough. Additional convection is also possible along the outflow. Wind profiles favor some supercell development, along with possible clusters. Very large hail could accompany supercells. The east-west boundary should enhance low-level shear such that a higher probability for tornadoes will exist across southern portions of MN. Stronger heating across the Plains of NE into eastern WY will aid isolated-scattered thunderstorms across this portion of the SLGT Risk. Higher-based updrafts, but steep lapse rates suggest hail/wind will be the primary concerns. ...Northern Middle Atlantic region and upper Ohio Valley... Weak short-wave trough is advancing east across the upper Great Lakes region early this morning. Southern influence of this feature will encourage convective development by 18z across the upper OH Valley into upstate NY. Modest west-southwesterly flow at mid levels suggests some convective organization is possible; however, poor lapse rates and modest instability should result in mainly a damaging wind threat with the most organized convection. Some consideration was given for higher probabilities across portions of the northern Middle Atlantic into southern NY, but weak lapse rates are concerning and deep-layer shear is not that strong. Even so, gusty winds will likely be noted with this activity as it spreads across PA/NY toward the western parts of southern New England. ..Darrow/Lyons.. 06/28/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1241 AM CDT Sat Jun 28 2025 Valid 281200Z - 291200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE UPPER MIDWEST TO THE BLACK HILLS REGION... ...SUMMARY... Scattered strong to severe thunderstorms, perhaps including one or two organizing clusters, will pose a risk for severe hail, wind and perhaps a couple of tornadoes across parts of the Upper Midwest into the Plains of South Dakota and Nebraska. ...Upper Midwest to the Black Hills of South Dakota... Seasonally typical early summer pattern will be noted today as stronger westerlies are confined to the northern U.S., and much weaker flow is observed across the southern two-thirds of the CONUS. Latest water-vapor imagery suggests a few weak disturbances are translating across the northern Rockies toward the northern Plains and this will shunt the primary synoptic boundary across much of the Dakotas into the upper MS Valley by early evening. This boundary will prove instrumental in focusing deep convection during the afternoon/evening hours. Early this morning, scattered clusters of strong/severe thunderstorms are propagating southeast across the eastern Dakotas. This activity will advance into the upper MS Valley early in the period as LLJ focuses across eastern SD into northern MN. While some severe threat will be noted with a possible MCS at daybreak, convective outflow will largely influence subsequent regeneration. Latest model guidance suggests an east-west boundary will drape itself across western WI/southern MN by 18z, likely modified by the aforementioned early-day MCS. Boundary-layer heating is expected to aid buoyancy across the Dakotas southeast of the cold front, and scattered thunderstorms should readily develop along this wind shift by late afternoon, aided in part by a weak short wave trough. Additional convection is also possible along the outflow. Wind profiles favor some supercell development, along with possible clusters. Very large hail could accompany supercells. The east-west boundary should enhance low-level shear such that a higher probability for tornadoes will exist across southern portions of MN. Stronger heating across the Plains of NE into eastern WY will aid isolated-scattered thunderstorms across this portion of the SLGT Risk. Higher-based updrafts, but steep lapse rates suggest hail/wind will be the primary concerns. ...Northern Middle Atlantic region and upper Ohio Valley... Weak short-wave trough is advancing east across the upper Great Lakes region early this morning. Southern influence of this feature will encourage convective development by 18z across the upper OH Valley into upstate NY. Modest west-southwesterly flow at mid levels suggests some convective organization is possible; however, poor lapse rates and modest instability should result in mainly a damaging wind threat with the most organized convection. Some consideration was given for higher probabilities across portions of the northern Middle Atlantic into southern NY, but weak lapse rates are concerning and deep-layer shear is not that strong. Even so, gusty winds will likely be noted with this activity as it spreads across PA/NY toward the western parts of southern New England. ..Darrow/Lyons.. 06/28/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1241 AM CDT Sat Jun 28 2025 Valid 281200Z - 291200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE UPPER MIDWEST TO THE BLACK HILLS REGION... ...SUMMARY... Scattered strong to severe thunderstorms, perhaps including one or two organizing clusters, will pose a risk for severe hail, wind and perhaps a couple of tornadoes across parts of the Upper Midwest into the Plains of South Dakota and Nebraska. ...Upper Midwest to the Black Hills of South Dakota... Seasonally typical early summer pattern will be noted today as stronger westerlies are confined to the northern U.S., and much weaker flow is observed across the southern two-thirds of the CONUS. Latest water-vapor imagery suggests a few weak disturbances are translating across the northern Rockies toward the northern Plains and this will shunt the primary synoptic boundary across much of the Dakotas into the upper MS Valley by early evening. This boundary will prove instrumental in focusing deep convection during the afternoon/evening hours. Early this morning, scattered clusters of strong/severe thunderstorms are propagating southeast across the eastern Dakotas. This activity will advance into the upper MS Valley early in the period as LLJ focuses across eastern SD into northern MN. While some severe threat will be noted with a possible MCS at daybreak, convective outflow will largely influence subsequent regeneration. Latest model guidance suggests an east-west boundary will drape itself across western WI/southern MN by 18z, likely modified by the aforementioned early-day MCS. Boundary-layer heating is expected to aid buoyancy across the Dakotas southeast of the cold front, and scattered thunderstorms should readily develop along this wind shift by late afternoon, aided in part by a weak short wave trough. Additional convection is also possible along the outflow. Wind profiles favor some supercell development, along with possible clusters. Very large hail could accompany supercells. The east-west boundary should enhance low-level shear such that a higher probability for tornadoes will exist across southern portions of MN. Stronger heating across the Plains of NE into eastern WY will aid isolated-scattered thunderstorms across this portion of the SLGT Risk. Higher-based updrafts, but steep lapse rates suggest hail/wind will be the primary concerns. ...Northern Middle Atlantic region and upper Ohio Valley... Weak short-wave trough is advancing east across the upper Great Lakes region early this morning. Southern influence of this feature will encourage convective development by 18z across the upper OH Valley into upstate NY. Modest west-southwesterly flow at mid levels suggests some convective organization is possible; however, poor lapse rates and modest instability should result in mainly a damaging wind threat with the most organized convection. Some consideration was given for higher probabilities across portions of the northern Middle Atlantic into southern NY, but weak lapse rates are concerning and deep-layer shear is not that strong. Even so, gusty winds will likely be noted with this activity as it spreads across PA/NY toward the western parts of southern New England. ..Darrow/Lyons.. 06/28/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1241 AM CDT Sat Jun 28 2025 Valid 281200Z - 291200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE UPPER MIDWEST TO THE BLACK HILLS REGION... ...SUMMARY... Scattered strong to severe thunderstorms, perhaps including one or two organizing clusters, will pose a risk for severe hail, wind and perhaps a couple of tornadoes across parts of the Upper Midwest into the Plains of South Dakota and Nebraska. ...Upper Midwest to the Black Hills of South Dakota... Seasonally typical early summer pattern will be noted today as stronger westerlies are confined to the northern U.S., and much weaker flow is observed across the southern two-thirds of the CONUS. Latest water-vapor imagery suggests a few weak disturbances are translating across the northern Rockies toward the northern Plains and this will shunt the primary synoptic boundary across much of the Dakotas into the upper MS Valley by early evening. This boundary will prove instrumental in focusing deep convection during the afternoon/evening hours. Early this morning, scattered clusters of strong/severe thunderstorms are propagating southeast across the eastern Dakotas. This activity will advance into the upper MS Valley early in the period as LLJ focuses across eastern SD into northern MN. While some severe threat will be noted with a possible MCS at daybreak, convective outflow will largely influence subsequent regeneration. Latest model guidance suggests an east-west boundary will drape itself across western WI/southern MN by 18z, likely modified by the aforementioned early-day MCS. Boundary-layer heating is expected to aid buoyancy across the Dakotas southeast of the cold front, and scattered thunderstorms should readily develop along this wind shift by late afternoon, aided in part by a weak short wave trough. Additional convection is also possible along the outflow. Wind profiles favor some supercell development, along with possible clusters. Very large hail could accompany supercells. The east-west boundary should enhance low-level shear such that a higher probability for tornadoes will exist across southern portions of MN. Stronger heating across the Plains of NE into eastern WY will aid isolated-scattered thunderstorms across this portion of the SLGT Risk. Higher-based updrafts, but steep lapse rates suggest hail/wind will be the primary concerns. ...Northern Middle Atlantic region and upper Ohio Valley... Weak short-wave trough is advancing east across the upper Great Lakes region early this morning. Southern influence of this feature will encourage convective development by 18z across the upper OH Valley into upstate NY. Modest west-southwesterly flow at mid levels suggests some convective organization is possible; however, poor lapse rates and modest instability should result in mainly a damaging wind threat with the most organized convection. Some consideration was given for higher probabilities across portions of the northern Middle Atlantic into southern NY, but weak lapse rates are concerning and deep-layer shear is not that strong. Even so, gusty winds will likely be noted with this activity as it spreads across PA/NY toward the western parts of southern New England. ..Darrow/Lyons.. 06/28/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1241 AM CDT Sat Jun 28 2025 Valid 281200Z - 291200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE UPPER MIDWEST TO THE BLACK HILLS REGION... ...SUMMARY... Scattered strong to severe thunderstorms, perhaps including one or two organizing clusters, will pose a risk for severe hail, wind and perhaps a couple of tornadoes across parts of the Upper Midwest into the Plains of South Dakota and Nebraska. ...Upper Midwest to the Black Hills of South Dakota... Seasonally typical early summer pattern will be noted today as stronger westerlies are confined to the northern U.S., and much weaker flow is observed across the southern two-thirds of the CONUS. Latest water-vapor imagery suggests a few weak disturbances are translating across the northern Rockies toward the northern Plains and this will shunt the primary synoptic boundary across much of the Dakotas into the upper MS Valley by early evening. This boundary will prove instrumental in focusing deep convection during the afternoon/evening hours. Early this morning, scattered clusters of strong/severe thunderstorms are propagating southeast across the eastern Dakotas. This activity will advance into the upper MS Valley early in the period as LLJ focuses across eastern SD into northern MN. While some severe threat will be noted with a possible MCS at daybreak, convective outflow will largely influence subsequent regeneration. Latest model guidance suggests an east-west boundary will drape itself across western WI/southern MN by 18z, likely modified by the aforementioned early-day MCS. Boundary-layer heating is expected to aid buoyancy across the Dakotas southeast of the cold front, and scattered thunderstorms should readily develop along this wind shift by late afternoon, aided in part by a weak short wave trough. Additional convection is also possible along the outflow. Wind profiles favor some supercell development, along with possible clusters. Very large hail could accompany supercells. The east-west boundary should enhance low-level shear such that a higher probability for tornadoes will exist across southern portions of MN. Stronger heating across the Plains of NE into eastern WY will aid isolated-scattered thunderstorms across this portion of the SLGT Risk. Higher-based updrafts, but steep lapse rates suggest hail/wind will be the primary concerns. ...Northern Middle Atlantic region and upper Ohio Valley... Weak short-wave trough is advancing east across the upper Great Lakes region early this morning. Southern influence of this feature will encourage convective development by 18z across the upper OH Valley into upstate NY. Modest west-southwesterly flow at mid levels suggests some convective organization is possible; however, poor lapse rates and modest instability should result in mainly a damaging wind threat with the most organized convection. Some consideration was given for higher probabilities across portions of the northern Middle Atlantic into southern NY, but weak lapse rates are concerning and deep-layer shear is not that strong. Even so, gusty winds will likely be noted with this activity as it spreads across PA/NY toward the western parts of southern New England. ..Darrow/Lyons.. 06/28/2025 Read more