Aggregator

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0211 AM CDT Thu Jul 03 2025 Valid 031200Z - 041200Z ...Synopsis... A compact shortwave trough moving across northern CA will accompany 40-50 kt westerly flow across the northern Great Basin. This will encourage dry downslope flow across parts of western NV and the northern Great Basin. At the same time, continued monsoon moisture will allow scattered showers and thunderstorms over the Intermountain West with isolated lightning. ...Northern Great Basin... Dry and breezy conditions are expected today and tonight in the lee of the Sierra and northern Great Basin ahead of the shortwave trough. Sustained 15-20 mph surface winds are expected from the west/southwest through the day. A dry and deep boundary layer will also support RH below 15-20%. Despite some recent rainfall, area fuels remain receptive across much of NV and the northern Great Basin. Widespread elevated and locally critical fire-weather conditions are likely. ...Dry Thunder... As the upper trough moves into the West, monsoon moisture will be shunted eastward compared to the last several days. Still, PWATS around 0.6-0.8 inches across western CO and into the northern Rockies will be sufficient to support scattered showers and thunderstorms this afternoon and evening. Fuel receptiveness has decreased with multiple rounds of showers and storms this week. Still, drier pockets remain and lightning outside of the heavier precipitation cores will be capable of ignitions. This appears most likely over parts of northern CO to eastern ID, where less rainfall has been observed. Will maintain IsoDryT highlights for occasional lighting strikes within receptive fuels. ..Lyons.. 07/03/2025 ...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 0211 AM CDT Thu Jul 03 2025 Valid 031200Z - 041200Z ...Synopsis... A compact shortwave trough moving across northern CA will accompany 40-50 kt westerly flow across the northern Great Basin. This will encourage dry downslope flow across parts of western NV and the northern Great Basin. At the same time, continued monsoon moisture will allow scattered showers and thunderstorms over the Intermountain West with isolated lightning. ...Northern Great Basin... Dry and breezy conditions are expected today and tonight in the lee of the Sierra and northern Great Basin ahead of the shortwave trough. Sustained 15-20 mph surface winds are expected from the west/southwest through the day. A dry and deep boundary layer will also support RH below 15-20%. Despite some recent rainfall, area fuels remain receptive across much of NV and the northern Great Basin. Widespread elevated and locally critical fire-weather conditions are likely. ...Dry Thunder... As the upper trough moves into the West, monsoon moisture will be shunted eastward compared to the last several days. Still, PWATS around 0.6-0.8 inches across western CO and into the northern Rockies will be sufficient to support scattered showers and thunderstorms this afternoon and evening. Fuel receptiveness has decreased with multiple rounds of showers and storms this week. Still, drier pockets remain and lightning outside of the heavier precipitation cores will be capable of ignitions. This appears most likely over parts of northern CO to eastern ID, where less rainfall has been observed. Will maintain IsoDryT highlights for occasional lighting strikes within receptive fuels. ..Lyons.. 07/03/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Thu Jul 03 2025 Valid 041200Z - 051200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE CENTRAL PLAINS TO THE UPPER MIDWEST... ...SUMMARY... Scattered strong to severe thunderstorms are expected across portions of the northern Plains and Upper Midwest on Friday. ...Synopsis... A strong upper-trough will move off the northeast CONUS into the western Atlantic on Friday. Meanwhile, a ridge will move across the Great Lakes with a trough across the northern Plains into the Upper Midwest. An additional mid-level trough will move across the Northwest. ...Central Plains into the Upper Midwest... As a mid-level trough moves across the northern Plains, a surface low will deepen across eastern North Dakota on Friday. Ahead of this surface low and associated cold front, strong instability is forecast with dewpoints in the low 70s and temperatures in the low 80s. Widespread thunderstorm activity is anticipated along this frontal zone as ascent overspreads the front with an uncapped warm sector. Some embedded shortwave jet streaks will move through the southwesterly flow across the warm sector. Within these zones of stronger mid-level flow, shear may be more favorable and support a greater severe weather threat. However, the locations of these mesoscale regions with a more favorable environment remain uncertain at this time. ...ID/MT... A strong shortwave trough will track into the western states on Friday, promoting scattered afternoon thunderstorm development over parts of the northern Great Basin and northern Rockies. There is some concern for a few storms capable of damaging winds and hail over the region Friday evening, but model solutions remain to diverse to add a risk area at this time. ..Bentley.. 07/03/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Thu Jul 03 2025 Valid 041200Z - 051200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE CENTRAL PLAINS TO THE UPPER MIDWEST... ...SUMMARY... Scattered strong to severe thunderstorms are expected across portions of the northern Plains and Upper Midwest on Friday. ...Synopsis... A strong upper-trough will move off the northeast CONUS into the western Atlantic on Friday. Meanwhile, a ridge will move across the Great Lakes with a trough across the northern Plains into the Upper Midwest. An additional mid-level trough will move across the Northwest. ...Central Plains into the Upper Midwest... As a mid-level trough moves across the northern Plains, a surface low will deepen across eastern North Dakota on Friday. Ahead of this surface low and associated cold front, strong instability is forecast with dewpoints in the low 70s and temperatures in the low 80s. Widespread thunderstorm activity is anticipated along this frontal zone as ascent overspreads the front with an uncapped warm sector. Some embedded shortwave jet streaks will move through the southwesterly flow across the warm sector. Within these zones of stronger mid-level flow, shear may be more favorable and support a greater severe weather threat. However, the locations of these mesoscale regions with a more favorable environment remain uncertain at this time. ...ID/MT... A strong shortwave trough will track into the western states on Friday, promoting scattered afternoon thunderstorm development over parts of the northern Great Basin and northern Rockies. There is some concern for a few storms capable of damaging winds and hail over the region Friday evening, but model solutions remain to diverse to add a risk area at this time. ..Bentley.. 07/03/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Thu Jul 03 2025 Valid 041200Z - 051200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE CENTRAL PLAINS TO THE UPPER MIDWEST... ...SUMMARY... Scattered strong to severe thunderstorms are expected across portions of the northern Plains and Upper Midwest on Friday. ...Synopsis... A strong upper-trough will move off the northeast CONUS into the western Atlantic on Friday. Meanwhile, a ridge will move across the Great Lakes with a trough across the northern Plains into the Upper Midwest. An additional mid-level trough will move across the Northwest. ...Central Plains into the Upper Midwest... As a mid-level trough moves across the northern Plains, a surface low will deepen across eastern North Dakota on Friday. Ahead of this surface low and associated cold front, strong instability is forecast with dewpoints in the low 70s and temperatures in the low 80s. Widespread thunderstorm activity is anticipated along this frontal zone as ascent overspreads the front with an uncapped warm sector. Some embedded shortwave jet streaks will move through the southwesterly flow across the warm sector. Within these zones of stronger mid-level flow, shear may be more favorable and support a greater severe weather threat. However, the locations of these mesoscale regions with a more favorable environment remain uncertain at this time. ...ID/MT... A strong shortwave trough will track into the western states on Friday, promoting scattered afternoon thunderstorm development over parts of the northern Great Basin and northern Rockies. There is some concern for a few storms capable of damaging winds and hail over the region Friday evening, but model solutions remain to diverse to add a risk area at this time. ..Bentley.. 07/03/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Thu Jul 03 2025 Valid 041200Z - 051200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE CENTRAL PLAINS TO THE UPPER MIDWEST... ...SUMMARY... Scattered strong to severe thunderstorms are expected across portions of the northern Plains and Upper Midwest on Friday. ...Synopsis... A strong upper-trough will move off the northeast CONUS into the western Atlantic on Friday. Meanwhile, a ridge will move across the Great Lakes with a trough across the northern Plains into the Upper Midwest. An additional mid-level trough will move across the Northwest. ...Central Plains into the Upper Midwest... As a mid-level trough moves across the northern Plains, a surface low will deepen across eastern North Dakota on Friday. Ahead of this surface low and associated cold front, strong instability is forecast with dewpoints in the low 70s and temperatures in the low 80s. Widespread thunderstorm activity is anticipated along this frontal zone as ascent overspreads the front with an uncapped warm sector. Some embedded shortwave jet streaks will move through the southwesterly flow across the warm sector. Within these zones of stronger mid-level flow, shear may be more favorable and support a greater severe weather threat. However, the locations of these mesoscale regions with a more favorable environment remain uncertain at this time. ...ID/MT... A strong shortwave trough will track into the western states on Friday, promoting scattered afternoon thunderstorm development over parts of the northern Great Basin and northern Rockies. There is some concern for a few storms capable of damaging winds and hail over the region Friday evening, but model solutions remain to diverse to add a risk area at this time. ..Bentley.. 07/03/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Thu Jul 03 2025 Valid 041200Z - 051200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE CENTRAL PLAINS TO THE UPPER MIDWEST... ...SUMMARY... Scattered strong to severe thunderstorms are expected across portions of the northern Plains and Upper Midwest on Friday. ...Synopsis... A strong upper-trough will move off the northeast CONUS into the western Atlantic on Friday. Meanwhile, a ridge will move across the Great Lakes with a trough across the northern Plains into the Upper Midwest. An additional mid-level trough will move across the Northwest. ...Central Plains into the Upper Midwest... As a mid-level trough moves across the northern Plains, a surface low will deepen across eastern North Dakota on Friday. Ahead of this surface low and associated cold front, strong instability is forecast with dewpoints in the low 70s and temperatures in the low 80s. Widespread thunderstorm activity is anticipated along this frontal zone as ascent overspreads the front with an uncapped warm sector. Some embedded shortwave jet streaks will move through the southwesterly flow across the warm sector. Within these zones of stronger mid-level flow, shear may be more favorable and support a greater severe weather threat. However, the locations of these mesoscale regions with a more favorable environment remain uncertain at this time. ...ID/MT... A strong shortwave trough will track into the western states on Friday, promoting scattered afternoon thunderstorm development over parts of the northern Great Basin and northern Rockies. There is some concern for a few storms capable of damaging winds and hail over the region Friday evening, but model solutions remain to diverse to add a risk area at this time. ..Bentley.. 07/03/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Thu Jul 03 2025 Valid 041200Z - 051200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE CENTRAL PLAINS TO THE UPPER MIDWEST... ...SUMMARY... Scattered strong to severe thunderstorms are expected across portions of the northern Plains and Upper Midwest on Friday. ...Synopsis... A strong upper-trough will move off the northeast CONUS into the western Atlantic on Friday. Meanwhile, a ridge will move across the Great Lakes with a trough across the northern Plains into the Upper Midwest. An additional mid-level trough will move across the Northwest. ...Central Plains into the Upper Midwest... As a mid-level trough moves across the northern Plains, a surface low will deepen across eastern North Dakota on Friday. Ahead of this surface low and associated cold front, strong instability is forecast with dewpoints in the low 70s and temperatures in the low 80s. Widespread thunderstorm activity is anticipated along this frontal zone as ascent overspreads the front with an uncapped warm sector. Some embedded shortwave jet streaks will move through the southwesterly flow across the warm sector. Within these zones of stronger mid-level flow, shear may be more favorable and support a greater severe weather threat. However, the locations of these mesoscale regions with a more favorable environment remain uncertain at this time. ...ID/MT... A strong shortwave trough will track into the western states on Friday, promoting scattered afternoon thunderstorm development over parts of the northern Great Basin and northern Rockies. There is some concern for a few storms capable of damaging winds and hail over the region Friday evening, but model solutions remain to diverse to add a risk area at this time. ..Bentley.. 07/03/2025 Read more

MD 1545 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR SOUTHEAST SD...NORTHEAST NE...NORTHWEST IA...AND FAR SOUTHWEST MN
Mesoscale Discussion 1545 NWS Storm Prediction Center Norman OK 1152 PM CDT Wed Jul 02 2025 Areas affected...Southeast SD...northeast NE...northwest IA...and far southwest MN Concerning...Severe potential...Watch unlikely Valid 030452Z - 030645Z Probability of Watch Issuance...5 percent SUMMARY...Isolated instances of severe hail will be possible with the stronger storms tonight. DISCUSSION...In response to weak low-level warm advection, isolated thunderstorms are developing along the northeastern periphery of a large-scale ridge. Here, 30-40 kt of midlevel northwesterly flow is yielding an elongated/mostly straight hodograph (around 30 kt of effective shear). This wind profile, coupled with an influx of steep midlevel lapse rates atop a shallow low-level stable layer, may support a couple elevated/transient supercell structures -- capable of producing isolated severe hail. Given the weak forcing for ascent, storm longevity and overall evolution is uncertain. ..Weinman/Guyer.. 07/03/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...DMX...FSD...OAX...LBF... LAT...LON 42229747 43049896 43489895 44059853 44239784 44049706 43639595 43099519 42469511 42069558 41969661 42229747 MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1230 AM CDT Thu Jul 03 2025 Valid 031200Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHEAST AND NORTHERN PLAINS... ...SUMMARY... Scattered severe thunderstorms capable of producing severe/damaging winds and large hail are forecast across parts of the Northeast and northern Plains today. ...Northeast... An upper trough with an embedded 40-50 kt mid-level speed maximum will pivot across the Northeast today. A related surface cold front will likewise develop eastward across this region through the afternoon/evening. Filtered daytime heating of a seasonably moist low-level airmass will support the development of moderate instability along/ahead of the cold front by late morning/early afternoon. Aided by the enhanced mid-level flow, deep-layer shear will likely be strong enough to support updraft organization, including a mix of multicells and perhaps some supercells. Scattered severe/damaging winds should be the primary severe threat as low-level lapse rates gradually steepen. But, some large hail may occur given favorable shear, especially if any supercells can be sustained. The Slight Risk has been expanded northward to include more of New England, as recent guidance trends show potential for organized severe convection along/ahead much of the length of the front. ...Northern Plains... An upper ridge will persist over much of the Plains today. Even so, a weak mid-level disturbance is forecast to advance eastward from MT across the northern Plains this afternoon/evening on the northern periphery of the upper ridge. This feature should encourage isolated to scattered intense thunderstorm development along/near a warm front extending across parts of ND by late afternoon/early evening. Moderate to strong instability is expected along/near this boundary, aided by steep lapse rates aloft. Modest low-level southerly flow is forecast to gradually veer and strengthen with height through mid/upper levels. This will support sufficient deep-layer shear (30-40 kt) for organized convection, including some supercells initially across western/central ND. These supercells should pose a threat for scattered large hail, some of which may be 2+ inches in diameter given a rather favorable thermodynamic environment forecast. With time this evening, there may be some potential for upscale growth into a small bowing cluster with eastward extent into central/eastern ND. If this mode transition occurs, then the severe/damaging wind threat would likewise increase. Although low-level flow should remain fairly modest, a tornado or two also appears possible, particularly along/near the front where effective SRH should be locally enhanced. ...Upper Midwest... Compared to the northern Plains, there is generally less confidence in overall thunderstorm coverage and development across much of the Upper Midwest through the period. Weak forcing aloft and the persistence of the upper ridge should tend to limit convective development in an otherwise moderately to strongly unstable airmass. Still, any thunderstorms which can develop, perhaps aided by modest low-level warm advection this evening/tonight, could pose an isolated severe hail/wind threat. The Marginal Risk area has been adjusted northward/westward some based on latest guidance trends showing multiple potential zones of isolated strong/severe thunderstorms. ..Gleason/Lyons.. 07/03/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1230 AM CDT Thu Jul 03 2025 Valid 031200Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHEAST AND NORTHERN PLAINS... ...SUMMARY... Scattered severe thunderstorms capable of producing severe/damaging winds and large hail are forecast across parts of the Northeast and northern Plains today. ...Northeast... An upper trough with an embedded 40-50 kt mid-level speed maximum will pivot across the Northeast today. A related surface cold front will likewise develop eastward across this region through the afternoon/evening. Filtered daytime heating of a seasonably moist low-level airmass will support the development of moderate instability along/ahead of the cold front by late morning/early afternoon. Aided by the enhanced mid-level flow, deep-layer shear will likely be strong enough to support updraft organization, including a mix of multicells and perhaps some supercells. Scattered severe/damaging winds should be the primary severe threat as low-level lapse rates gradually steepen. But, some large hail may occur given favorable shear, especially if any supercells can be sustained. The Slight Risk has been expanded northward to include more of New England, as recent guidance trends show potential for organized severe convection along/ahead much of the length of the front. ...Northern Plains... An upper ridge will persist over much of the Plains today. Even so, a weak mid-level disturbance is forecast to advance eastward from MT across the northern Plains this afternoon/evening on the northern periphery of the upper ridge. This feature should encourage isolated to scattered intense thunderstorm development along/near a warm front extending across parts of ND by late afternoon/early evening. Moderate to strong instability is expected along/near this boundary, aided by steep lapse rates aloft. Modest low-level southerly flow is forecast to gradually veer and strengthen with height through mid/upper levels. This will support sufficient deep-layer shear (30-40 kt) for organized convection, including some supercells initially across western/central ND. These supercells should pose a threat for scattered large hail, some of which may be 2+ inches in diameter given a rather favorable thermodynamic environment forecast. With time this evening, there may be some potential for upscale growth into a small bowing cluster with eastward extent into central/eastern ND. If this mode transition occurs, then the severe/damaging wind threat would likewise increase. Although low-level flow should remain fairly modest, a tornado or two also appears possible, particularly along/near the front where effective SRH should be locally enhanced. ...Upper Midwest... Compared to the northern Plains, there is generally less confidence in overall thunderstorm coverage and development across much of the Upper Midwest through the period. Weak forcing aloft and the persistence of the upper ridge should tend to limit convective development in an otherwise moderately to strongly unstable airmass. Still, any thunderstorms which can develop, perhaps aided by modest low-level warm advection this evening/tonight, could pose an isolated severe hail/wind threat. The Marginal Risk area has been adjusted northward/westward some based on latest guidance trends showing multiple potential zones of isolated strong/severe thunderstorms. ..Gleason/Lyons.. 07/03/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1230 AM CDT Thu Jul 03 2025 Valid 031200Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHEAST AND NORTHERN PLAINS... ...SUMMARY... Scattered severe thunderstorms capable of producing severe/damaging winds and large hail are forecast across parts of the Northeast and northern Plains today. ...Northeast... An upper trough with an embedded 40-50 kt mid-level speed maximum will pivot across the Northeast today. A related surface cold front will likewise develop eastward across this region through the afternoon/evening. Filtered daytime heating of a seasonably moist low-level airmass will support the development of moderate instability along/ahead of the cold front by late morning/early afternoon. Aided by the enhanced mid-level flow, deep-layer shear will likely be strong enough to support updraft organization, including a mix of multicells and perhaps some supercells. Scattered severe/damaging winds should be the primary severe threat as low-level lapse rates gradually steepen. But, some large hail may occur given favorable shear, especially if any supercells can be sustained. The Slight Risk has been expanded northward to include more of New England, as recent guidance trends show potential for organized severe convection along/ahead much of the length of the front. ...Northern Plains... An upper ridge will persist over much of the Plains today. Even so, a weak mid-level disturbance is forecast to advance eastward from MT across the northern Plains this afternoon/evening on the northern periphery of the upper ridge. This feature should encourage isolated to scattered intense thunderstorm development along/near a warm front extending across parts of ND by late afternoon/early evening. Moderate to strong instability is expected along/near this boundary, aided by steep lapse rates aloft. Modest low-level southerly flow is forecast to gradually veer and strengthen with height through mid/upper levels. This will support sufficient deep-layer shear (30-40 kt) for organized convection, including some supercells initially across western/central ND. These supercells should pose a threat for scattered large hail, some of which may be 2+ inches in diameter given a rather favorable thermodynamic environment forecast. With time this evening, there may be some potential for upscale growth into a small bowing cluster with eastward extent into central/eastern ND. If this mode transition occurs, then the severe/damaging wind threat would likewise increase. Although low-level flow should remain fairly modest, a tornado or two also appears possible, particularly along/near the front where effective SRH should be locally enhanced. ...Upper Midwest... Compared to the northern Plains, there is generally less confidence in overall thunderstorm coverage and development across much of the Upper Midwest through the period. Weak forcing aloft and the persistence of the upper ridge should tend to limit convective development in an otherwise moderately to strongly unstable airmass. Still, any thunderstorms which can develop, perhaps aided by modest low-level warm advection this evening/tonight, could pose an isolated severe hail/wind threat. The Marginal Risk area has been adjusted northward/westward some based on latest guidance trends showing multiple potential zones of isolated strong/severe thunderstorms. ..Gleason/Lyons.. 07/03/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1230 AM CDT Thu Jul 03 2025 Valid 031200Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHEAST AND NORTHERN PLAINS... ...SUMMARY... Scattered severe thunderstorms capable of producing severe/damaging winds and large hail are forecast across parts of the Northeast and northern Plains today. ...Northeast... An upper trough with an embedded 40-50 kt mid-level speed maximum will pivot across the Northeast today. A related surface cold front will likewise develop eastward across this region through the afternoon/evening. Filtered daytime heating of a seasonably moist low-level airmass will support the development of moderate instability along/ahead of the cold front by late morning/early afternoon. Aided by the enhanced mid-level flow, deep-layer shear will likely be strong enough to support updraft organization, including a mix of multicells and perhaps some supercells. Scattered severe/damaging winds should be the primary severe threat as low-level lapse rates gradually steepen. But, some large hail may occur given favorable shear, especially if any supercells can be sustained. The Slight Risk has been expanded northward to include more of New England, as recent guidance trends show potential for organized severe convection along/ahead much of the length of the front. ...Northern Plains... An upper ridge will persist over much of the Plains today. Even so, a weak mid-level disturbance is forecast to advance eastward from MT across the northern Plains this afternoon/evening on the northern periphery of the upper ridge. This feature should encourage isolated to scattered intense thunderstorm development along/near a warm front extending across parts of ND by late afternoon/early evening. Moderate to strong instability is expected along/near this boundary, aided by steep lapse rates aloft. Modest low-level southerly flow is forecast to gradually veer and strengthen with height through mid/upper levels. This will support sufficient deep-layer shear (30-40 kt) for organized convection, including some supercells initially across western/central ND. These supercells should pose a threat for scattered large hail, some of which may be 2+ inches in diameter given a rather favorable thermodynamic environment forecast. With time this evening, there may be some potential for upscale growth into a small bowing cluster with eastward extent into central/eastern ND. If this mode transition occurs, then the severe/damaging wind threat would likewise increase. Although low-level flow should remain fairly modest, a tornado or two also appears possible, particularly along/near the front where effective SRH should be locally enhanced. ...Upper Midwest... Compared to the northern Plains, there is generally less confidence in overall thunderstorm coverage and development across much of the Upper Midwest through the period. Weak forcing aloft and the persistence of the upper ridge should tend to limit convective development in an otherwise moderately to strongly unstable airmass. Still, any thunderstorms which can develop, perhaps aided by modest low-level warm advection this evening/tonight, could pose an isolated severe hail/wind threat. The Marginal Risk area has been adjusted northward/westward some based on latest guidance trends showing multiple potential zones of isolated strong/severe thunderstorms. ..Gleason/Lyons.. 07/03/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1230 AM CDT Thu Jul 03 2025 Valid 031200Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHEAST AND NORTHERN PLAINS... ...SUMMARY... Scattered severe thunderstorms capable of producing severe/damaging winds and large hail are forecast across parts of the Northeast and northern Plains today. ...Northeast... An upper trough with an embedded 40-50 kt mid-level speed maximum will pivot across the Northeast today. A related surface cold front will likewise develop eastward across this region through the afternoon/evening. Filtered daytime heating of a seasonably moist low-level airmass will support the development of moderate instability along/ahead of the cold front by late morning/early afternoon. Aided by the enhanced mid-level flow, deep-layer shear will likely be strong enough to support updraft organization, including a mix of multicells and perhaps some supercells. Scattered severe/damaging winds should be the primary severe threat as low-level lapse rates gradually steepen. But, some large hail may occur given favorable shear, especially if any supercells can be sustained. The Slight Risk has been expanded northward to include more of New England, as recent guidance trends show potential for organized severe convection along/ahead much of the length of the front. ...Northern Plains... An upper ridge will persist over much of the Plains today. Even so, a weak mid-level disturbance is forecast to advance eastward from MT across the northern Plains this afternoon/evening on the northern periphery of the upper ridge. This feature should encourage isolated to scattered intense thunderstorm development along/near a warm front extending across parts of ND by late afternoon/early evening. Moderate to strong instability is expected along/near this boundary, aided by steep lapse rates aloft. Modest low-level southerly flow is forecast to gradually veer and strengthen with height through mid/upper levels. This will support sufficient deep-layer shear (30-40 kt) for organized convection, including some supercells initially across western/central ND. These supercells should pose a threat for scattered large hail, some of which may be 2+ inches in diameter given a rather favorable thermodynamic environment forecast. With time this evening, there may be some potential for upscale growth into a small bowing cluster with eastward extent into central/eastern ND. If this mode transition occurs, then the severe/damaging wind threat would likewise increase. Although low-level flow should remain fairly modest, a tornado or two also appears possible, particularly along/near the front where effective SRH should be locally enhanced. ...Upper Midwest... Compared to the northern Plains, there is generally less confidence in overall thunderstorm coverage and development across much of the Upper Midwest through the period. Weak forcing aloft and the persistence of the upper ridge should tend to limit convective development in an otherwise moderately to strongly unstable airmass. Still, any thunderstorms which can develop, perhaps aided by modest low-level warm advection this evening/tonight, could pose an isolated severe hail/wind threat. The Marginal Risk area has been adjusted northward/westward some based on latest guidance trends showing multiple potential zones of isolated strong/severe thunderstorms. ..Gleason/Lyons.. 07/03/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1230 AM CDT Thu Jul 03 2025 Valid 031200Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHEAST AND NORTHERN PLAINS... ...SUMMARY... Scattered severe thunderstorms capable of producing severe/damaging winds and large hail are forecast across parts of the Northeast and northern Plains today. ...Northeast... An upper trough with an embedded 40-50 kt mid-level speed maximum will pivot across the Northeast today. A related surface cold front will likewise develop eastward across this region through the afternoon/evening. Filtered daytime heating of a seasonably moist low-level airmass will support the development of moderate instability along/ahead of the cold front by late morning/early afternoon. Aided by the enhanced mid-level flow, deep-layer shear will likely be strong enough to support updraft organization, including a mix of multicells and perhaps some supercells. Scattered severe/damaging winds should be the primary severe threat as low-level lapse rates gradually steepen. But, some large hail may occur given favorable shear, especially if any supercells can be sustained. The Slight Risk has been expanded northward to include more of New England, as recent guidance trends show potential for organized severe convection along/ahead much of the length of the front. ...Northern Plains... An upper ridge will persist over much of the Plains today. Even so, a weak mid-level disturbance is forecast to advance eastward from MT across the northern Plains this afternoon/evening on the northern periphery of the upper ridge. This feature should encourage isolated to scattered intense thunderstorm development along/near a warm front extending across parts of ND by late afternoon/early evening. Moderate to strong instability is expected along/near this boundary, aided by steep lapse rates aloft. Modest low-level southerly flow is forecast to gradually veer and strengthen with height through mid/upper levels. This will support sufficient deep-layer shear (30-40 kt) for organized convection, including some supercells initially across western/central ND. These supercells should pose a threat for scattered large hail, some of which may be 2+ inches in diameter given a rather favorable thermodynamic environment forecast. With time this evening, there may be some potential for upscale growth into a small bowing cluster with eastward extent into central/eastern ND. If this mode transition occurs, then the severe/damaging wind threat would likewise increase. Although low-level flow should remain fairly modest, a tornado or two also appears possible, particularly along/near the front where effective SRH should be locally enhanced. ...Upper Midwest... Compared to the northern Plains, there is generally less confidence in overall thunderstorm coverage and development across much of the Upper Midwest through the period. Weak forcing aloft and the persistence of the upper ridge should tend to limit convective development in an otherwise moderately to strongly unstable airmass. Still, any thunderstorms which can develop, perhaps aided by modest low-level warm advection this evening/tonight, could pose an isolated severe hail/wind threat. The Marginal Risk area has been adjusted northward/westward some based on latest guidance trends showing multiple potential zones of isolated strong/severe thunderstorms. ..Gleason/Lyons.. 07/03/2025 Read more

000
ABPZ20 KNHC 030511
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 PM PDT Wed Jul 2 2025

For the eastern and central North Pacific east of 180 longitude:

Active Systems:
The National Hurricane Center is issuing advisories on Hurricane
Flossie, located in the eastern Pacific basin, a couple hundred
miles south of the southern tip of the Baja California peninsula.

South of the Gulf of Tehuantepec:
An area of disturbed weather associated with a tropical wave is
producing disorganized showers and thunderstorms several hundred
miles south of the Gulf of Tehuantepec. Environmental conditions
appear conducive for some gradual development of this system during
the next few days, and a tropical depression is likely to form over
the weekend or early next week while it moves generally
west-northwestward.
* Formation chance through 48 hours...low...30 percent.
* Formation chance through 7 days...high...80 percent.

$$
Forecaster Jelsema/Gibbs

5-Day Uncertainty Track last updated Thu, 03 Jul 2025 02:42:52 GMT


Wind Speed Probabilities last updated Thu, 03 Jul 2025 03:21:53 GMT

5-Day Uncertainty Track last updated Thu, 03 Jul 2025 02:42:52 GMT


Wind Speed Probabilities last updated Thu, 03 Jul 2025 02:42:52 GMT

Issued at 800 PM MST Wed Jul 02 2025 000 WTPZ41 KNHC 030241 TCDEP1 Hurricane Flossie Discussion Number 16 NWS National Hurricane Center Miami FL EP062025 800 PM MST Wed Jul 02 2025 Flossie is rapidly weakening, with deep convection now confined to the western and southwestern quadrants of the circulation and the low-level center almost fully exposed. This trend is supported by recent Dvorak classifications, with current intensity estimates from TAFB at 4.5/77 kt and SAB at 4.0/65 kt. Objective satellite intensity estimates range between 56 and 72 kt. A blend of these data supports lowering the initial intensity to 65 kt. The initial motion is 305/7 kt. Flossie is moving along the southwestern periphery of a subtropical ridge, with a weakness in the ridge induced by a mid- to upper-level trough over the Baja California region. A continued northwestward motion is expected during the next couple of days, followed by a gradual turn toward the west-northwest as the system decouples vertically. The latest forecast track remains very close to the previous advisory and is well-supported by the consensus aids. Rapid weakening is expected to continue as Flossie moves over progressively cooler waters and into a more stable and drier environment. The cyclone is forecast to become post-tropical by late Thursday, or within the next 24 hours, and degenerate into a remnant low shortly thereafter. The system is expected to dissipate by late Saturday, around 72 hours from now. FORECAST POSITIONS AND MAX WINDS INIT 03/0300Z 19.8N 110.2W 65 KT 75 MPH 12H 03/1200Z 20.4N 111.3W 55 KT 65 MPH 24H 04/0000Z 21.4N 112.7W 40 KT 45 MPH...POST-TROPICAL 36H 04/1200Z 22.6N 114.2W 30 KT 35 MPH...POST-TROP/REMNT LOW 48H 05/0000Z 23.6N 115.9W 25 KT 30 MPH...POST-TROP/REMNT LOW 60H 05/1200Z 24.1N 117.4W 20 KT 25 MPH...POST-TROP/REMNT LOW 72H 06/0000Z...DISSIPATED $$ Forecaster Gibbs/Jelsema/Blake

Issued at 0300 UTC THU JUL 03 2025 527 FOPZ11 KNHC 030240 PWSEP1 HURRICANE FLOSSIE WIND SPEED PROBABILITIES NUMBER 16 NWS NATIONAL HURRICANE CENTER MIAMI FL EP062025 0300 UTC THU JUL 03 2025 AT 0300Z THE CENTER OF HURRICANE FLOSSIE WAS LOCATED NEAR LATITUDE 19.8 NORTH...LONGITUDE 110.2 WEST WITH MAXIMUM SUSTAINED WINDS NEAR 65 KTS...75 MPH...120 KM/H. Z INDICATES COORDINATED UNIVERSAL TIME (GREENWICH) PACIFIC DAYLIGHT TIME (PDT)...SUBTRACT 7 HOURS FROM Z TIME HAWAIIAN STANDARD TIME (HST)...SUBTRACT 10 HOURS FROM Z TIME WIND SPEED PROBABILITY TABLE FOR SPECIFIC LOCATIONS CHANCES OF SUSTAINED (1-MINUTE AVERAGE) WIND SPEEDS OF AT LEAST ...34 KT (39 MPH... 63 KM/H)... ...50 KT (58 MPH... 93 KM/H)... ...64 KT (74 MPH...119 KM/H)... FOR LOCATIONS AND TIME PERIODS DURING THE NEXT 5 DAYS PROBABILITIES FOR LOCATIONS ARE GIVEN AS OP(CP) WHERE OP IS THE PROBABILITY OF THE EVENT BEGINNING DURING AN INDIVIDUAL TIME PERIOD (ONSET PROBABILITY) (CP) IS THE PROBABILITY OF THE EVENT OCCURRING BETWEEN 00Z THU AND THE FORECAST HOUR (CUMULATIVE PROBABILITY) PROBABILITIES ARE GIVEN IN PERCENT X INDICATES PROBABILITIES LESS THAN 1 PERCENT PROBABILITIES FOR 34 KT AND 50 KT ARE SHOWN AT A GIVEN LOCATION WHEN THE 5-DAY CUMULATIVE PROBABILITY IS AT LEAST 3 PERCENT. PROBABILITIES FOR 34...50...64 KT SHOWN WHEN THE 5-DAY 64-KT CUMULATIVE PROBABILITY IS AT LEAST 1 PERCENT. - - - - WIND SPEED PROBABILITIES FOR SELECTED LOCATIONS - - - - FROM FROM FROM FROM FROM FROM FROM TIME 00Z THU 12Z THU 00Z FRI 12Z FRI 00Z SAT 00Z SUN 00Z MON PERIODS TO TO TO TO TO TO TO 12Z THU 00Z FRI 12Z FRI 00Z SAT 00Z SUN 00Z MON 00Z TUE FORECAST HOUR (12) (24) (36) (48) (72) (96) (120) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - LOCATION KT 20N 110W 34 99 X(99) X(99) X(99) X(99) X(99) X(99) 20N 110W 50 99 1(99) X(99) X(99) X(99) X(99) X(99) 20N 110W 64 28 X(28) X(28) X(28) X(28) X(28) X(28) $$ FORECASTER GIBBS/JELSEMA/BLAKE