Severe Storms

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1106 AM CDT Sat Apr 13 2024 Valid 131630Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM FAR NORTHEAST CALIFORNIA INTO CENTRAL OREGON... ...SUMMARY... Thunderstorms with isolated severe hail and strong wind gusts will be possible this afternoon and early evening across parts of Oregon. ...Far Northeast California into Oregon... An upper low off the northern/central CA coast will continue to slowly migrate east through tonight. Deep-layer south/southeasterly flow on the northeast periphery of this cyclone will advect a plume of midlevel moisture and steep lapse rates over the area. Heating through broken cloud cover will allow temperatures to warm into the 60s F by mid-afternoon and MLCAPE around 500-1000 J/kg is forecast. Moderate deep shear, with 0-6km effective shear magnitudes near 35 kt will support organized clusters, or perhaps a supercell, developing in the 20-22z time frame. Isolated large hail around 1 to 1.5 inches in diameter will be possible with the strongest cells given steep lapse rates and favorable shear in the 4-6 km layer. In addition to hail, a deeply-mixed sub-cloud layer will result in inverted-v thermodynamic profiles, and isolated strong gusts may occur. While low-level moisture will remain a limiting factor for tornado potential, a brief spin-up can not be ruled out. Enlarged low-level hodographs are evident in forecast soundings and effective SRH will increase to 100-200 m2/s2 by 22-00z amid 0-3km MLCAPE near 100 J/kg. Have added a 2 percent tornado probability to reflect this low, but non-zero potential. Uncertainty in storm coverage will preclude an upgrade to Slight risk at this time. ...Great Lakes... A low-amplitude shortwave trough migrating through large-scale northwesterly flow regime will foster elevated thunderstorm development during the evening/overnight. Weak instability (MUCAPE generally less than 500 J/kg) will limit storm intensity, though steep midlevel lapse rates and cool temperatures aloft may be sufficient for a few instances of small hail. ..Leitman/Bentley.. 04/13/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1106 AM CDT Sat Apr 13 2024 Valid 131630Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM FAR NORTHEAST CALIFORNIA INTO CENTRAL OREGON... ...SUMMARY... Thunderstorms with isolated severe hail and strong wind gusts will be possible this afternoon and early evening across parts of Oregon. ...Far Northeast California into Oregon... An upper low off the northern/central CA coast will continue to slowly migrate east through tonight. Deep-layer south/southeasterly flow on the northeast periphery of this cyclone will advect a plume of midlevel moisture and steep lapse rates over the area. Heating through broken cloud cover will allow temperatures to warm into the 60s F by mid-afternoon and MLCAPE around 500-1000 J/kg is forecast. Moderate deep shear, with 0-6km effective shear magnitudes near 35 kt will support organized clusters, or perhaps a supercell, developing in the 20-22z time frame. Isolated large hail around 1 to 1.5 inches in diameter will be possible with the strongest cells given steep lapse rates and favorable shear in the 4-6 km layer. In addition to hail, a deeply-mixed sub-cloud layer will result in inverted-v thermodynamic profiles, and isolated strong gusts may occur. While low-level moisture will remain a limiting factor for tornado potential, a brief spin-up can not be ruled out. Enlarged low-level hodographs are evident in forecast soundings and effective SRH will increase to 100-200 m2/s2 by 22-00z amid 0-3km MLCAPE near 100 J/kg. Have added a 2 percent tornado probability to reflect this low, but non-zero potential. Uncertainty in storm coverage will preclude an upgrade to Slight risk at this time. ...Great Lakes... A low-amplitude shortwave trough migrating through large-scale northwesterly flow regime will foster elevated thunderstorm development during the evening/overnight. Weak instability (MUCAPE generally less than 500 J/kg) will limit storm intensity, though steep midlevel lapse rates and cool temperatures aloft may be sufficient for a few instances of small hail. ..Leitman/Bentley.. 04/13/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1106 AM CDT Sat Apr 13 2024 Valid 131630Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM FAR NORTHEAST CALIFORNIA INTO CENTRAL OREGON... ...SUMMARY... Thunderstorms with isolated severe hail and strong wind gusts will be possible this afternoon and early evening across parts of Oregon. ...Far Northeast California into Oregon... An upper low off the northern/central CA coast will continue to slowly migrate east through tonight. Deep-layer south/southeasterly flow on the northeast periphery of this cyclone will advect a plume of midlevel moisture and steep lapse rates over the area. Heating through broken cloud cover will allow temperatures to warm into the 60s F by mid-afternoon and MLCAPE around 500-1000 J/kg is forecast. Moderate deep shear, with 0-6km effective shear magnitudes near 35 kt will support organized clusters, or perhaps a supercell, developing in the 20-22z time frame. Isolated large hail around 1 to 1.5 inches in diameter will be possible with the strongest cells given steep lapse rates and favorable shear in the 4-6 km layer. In addition to hail, a deeply-mixed sub-cloud layer will result in inverted-v thermodynamic profiles, and isolated strong gusts may occur. While low-level moisture will remain a limiting factor for tornado potential, a brief spin-up can not be ruled out. Enlarged low-level hodographs are evident in forecast soundings and effective SRH will increase to 100-200 m2/s2 by 22-00z amid 0-3km MLCAPE near 100 J/kg. Have added a 2 percent tornado probability to reflect this low, but non-zero potential. Uncertainty in storm coverage will preclude an upgrade to Slight risk at this time. ...Great Lakes... A low-amplitude shortwave trough migrating through large-scale northwesterly flow regime will foster elevated thunderstorm development during the evening/overnight. Weak instability (MUCAPE generally less than 500 J/kg) will limit storm intensity, though steep midlevel lapse rates and cool temperatures aloft may be sufficient for a few instances of small hail. ..Leitman/Bentley.. 04/13/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1106 AM CDT Sat Apr 13 2024 Valid 131630Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM FAR NORTHEAST CALIFORNIA INTO CENTRAL OREGON... ...SUMMARY... Thunderstorms with isolated severe hail and strong wind gusts will be possible this afternoon and early evening across parts of Oregon. ...Far Northeast California into Oregon... An upper low off the northern/central CA coast will continue to slowly migrate east through tonight. Deep-layer south/southeasterly flow on the northeast periphery of this cyclone will advect a plume of midlevel moisture and steep lapse rates over the area. Heating through broken cloud cover will allow temperatures to warm into the 60s F by mid-afternoon and MLCAPE around 500-1000 J/kg is forecast. Moderate deep shear, with 0-6km effective shear magnitudes near 35 kt will support organized clusters, or perhaps a supercell, developing in the 20-22z time frame. Isolated large hail around 1 to 1.5 inches in diameter will be possible with the strongest cells given steep lapse rates and favorable shear in the 4-6 km layer. In addition to hail, a deeply-mixed sub-cloud layer will result in inverted-v thermodynamic profiles, and isolated strong gusts may occur. While low-level moisture will remain a limiting factor for tornado potential, a brief spin-up can not be ruled out. Enlarged low-level hodographs are evident in forecast soundings and effective SRH will increase to 100-200 m2/s2 by 22-00z amid 0-3km MLCAPE near 100 J/kg. Have added a 2 percent tornado probability to reflect this low, but non-zero potential. Uncertainty in storm coverage will preclude an upgrade to Slight risk at this time. ...Great Lakes... A low-amplitude shortwave trough migrating through large-scale northwesterly flow regime will foster elevated thunderstorm development during the evening/overnight. Weak instability (MUCAPE generally less than 500 J/kg) will limit storm intensity, though steep midlevel lapse rates and cool temperatures aloft may be sufficient for a few instances of small hail. ..Leitman/Bentley.. 04/13/2024 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1049 AM CDT Sat Apr 13 2024 Valid 131700Z - 141200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF CENTRAL KANSAS... Critical fire weather appears probable along the western fringe of greater surface moisture across eastern Kansas. Here, RH of near to just below 20% is likely along with low-level pressure gradients remaining strong enough into the afternoon to support around 20 mph winds with higher gusts. ..Wendt.. 04/13/2024 .PREV DISCUSSION... /ISSUED 0111 AM CDT Sat Apr 13 2024/ ...Synopsis... Elevated fire weather conditions are anticipated across a broad swath of the southern Great Basin to the southern/central Plains this afternoon. However, the fire weather threat will likely be focused primarily across portions of the southern High Plains where the overlap of receptive fuels and dry/windy conditions will be greatest. ...Southern High Plains to northern KS... 05 UTC surface observations show somewhat poor overnight RH recover with RH values remaining in the 15-30% range across eastern NM into far western TX. Additionally, regional 00 UTC soundings sampled very dry boundary-layer conditions across NM and western TX. This dry air mass will spread to the east/northeast through the afternoon as southwesterly winds increase in tandem with a deepening lee trough. Widespread RH values in the low teens to low 20s will likely coincide with 15-20 mph winds (gusting to 25-30 mph). Elevated fire weather conditions will likely be widespread across the southern High Plains into western TX, OK, and KS. However, rainfall over the past 72 hours across parts of TX and OK has limited fuel receptiveness based on recent rainfall analyses and fuel reports. Early spring green up is also more prevalent with eastern extent, which will further limit fire potential. Therefore, the Elevated risk area delineates where the best overlap of dry fine fuels and dry/windy conditions should occur. ...Upper Mississippi Valley... Southerly winds are expected to strengthen through the day in response to the deepening lee trough. Very limited moisture return until late in the day, coupled with strong diurnal warming, should result in areas of 25-35% RH with 15-20 mph winds. Localized elevated fire weather conditions will be possible across parts of IA, MN, and southwestern WI, but are expected to remain sufficiently limited spatially and temporally to negate the need for additional highlights. ...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 1049 AM CDT Sat Apr 13 2024 Valid 131700Z - 141200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF CENTRAL KANSAS... Critical fire weather appears probable along the western fringe of greater surface moisture across eastern Kansas. Here, RH of near to just below 20% is likely along with low-level pressure gradients remaining strong enough into the afternoon to support around 20 mph winds with higher gusts. ..Wendt.. 04/13/2024 .PREV DISCUSSION... /ISSUED 0111 AM CDT Sat Apr 13 2024/ ...Synopsis... Elevated fire weather conditions are anticipated across a broad swath of the southern Great Basin to the southern/central Plains this afternoon. However, the fire weather threat will likely be focused primarily across portions of the southern High Plains where the overlap of receptive fuels and dry/windy conditions will be greatest. ...Southern High Plains to northern KS... 05 UTC surface observations show somewhat poor overnight RH recover with RH values remaining in the 15-30% range across eastern NM into far western TX. Additionally, regional 00 UTC soundings sampled very dry boundary-layer conditions across NM and western TX. This dry air mass will spread to the east/northeast through the afternoon as southwesterly winds increase in tandem with a deepening lee trough. Widespread RH values in the low teens to low 20s will likely coincide with 15-20 mph winds (gusting to 25-30 mph). Elevated fire weather conditions will likely be widespread across the southern High Plains into western TX, OK, and KS. However, rainfall over the past 72 hours across parts of TX and OK has limited fuel receptiveness based on recent rainfall analyses and fuel reports. Early spring green up is also more prevalent with eastern extent, which will further limit fire potential. Therefore, the Elevated risk area delineates where the best overlap of dry fine fuels and dry/windy conditions should occur. ...Upper Mississippi Valley... Southerly winds are expected to strengthen through the day in response to the deepening lee trough. Very limited moisture return until late in the day, coupled with strong diurnal warming, should result in areas of 25-35% RH with 15-20 mph winds. Localized elevated fire weather conditions will be possible across parts of IA, MN, and southwestern WI, but are expected to remain sufficiently limited spatially and temporally to negate the need for additional highlights. ...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 1049 AM CDT Sat Apr 13 2024 Valid 131700Z - 141200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF CENTRAL KANSAS... Critical fire weather appears probable along the western fringe of greater surface moisture across eastern Kansas. Here, RH of near to just below 20% is likely along with low-level pressure gradients remaining strong enough into the afternoon to support around 20 mph winds with higher gusts. ..Wendt.. 04/13/2024 .PREV DISCUSSION... /ISSUED 0111 AM CDT Sat Apr 13 2024/ ...Synopsis... Elevated fire weather conditions are anticipated across a broad swath of the southern Great Basin to the southern/central Plains this afternoon. However, the fire weather threat will likely be focused primarily across portions of the southern High Plains where the overlap of receptive fuels and dry/windy conditions will be greatest. ...Southern High Plains to northern KS... 05 UTC surface observations show somewhat poor overnight RH recover with RH values remaining in the 15-30% range across eastern NM into far western TX. Additionally, regional 00 UTC soundings sampled very dry boundary-layer conditions across NM and western TX. This dry air mass will spread to the east/northeast through the afternoon as southwesterly winds increase in tandem with a deepening lee trough. Widespread RH values in the low teens to low 20s will likely coincide with 15-20 mph winds (gusting to 25-30 mph). Elevated fire weather conditions will likely be widespread across the southern High Plains into western TX, OK, and KS. However, rainfall over the past 72 hours across parts of TX and OK has limited fuel receptiveness based on recent rainfall analyses and fuel reports. Early spring green up is also more prevalent with eastern extent, which will further limit fire potential. Therefore, the Elevated risk area delineates where the best overlap of dry fine fuels and dry/windy conditions should occur. ...Upper Mississippi Valley... Southerly winds are expected to strengthen through the day in response to the deepening lee trough. Very limited moisture return until late in the day, coupled with strong diurnal warming, should result in areas of 25-35% RH with 15-20 mph winds. Localized elevated fire weather conditions will be possible across parts of IA, MN, and southwestern WI, but are expected to remain sufficiently limited spatially and temporally to negate the need for additional highlights. ...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 1049 AM CDT Sat Apr 13 2024 Valid 131700Z - 141200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF CENTRAL KANSAS... Critical fire weather appears probable along the western fringe of greater surface moisture across eastern Kansas. Here, RH of near to just below 20% is likely along with low-level pressure gradients remaining strong enough into the afternoon to support around 20 mph winds with higher gusts. ..Wendt.. 04/13/2024 .PREV DISCUSSION... /ISSUED 0111 AM CDT Sat Apr 13 2024/ ...Synopsis... Elevated fire weather conditions are anticipated across a broad swath of the southern Great Basin to the southern/central Plains this afternoon. However, the fire weather threat will likely be focused primarily across portions of the southern High Plains where the overlap of receptive fuels and dry/windy conditions will be greatest. ...Southern High Plains to northern KS... 05 UTC surface observations show somewhat poor overnight RH recover with RH values remaining in the 15-30% range across eastern NM into far western TX. Additionally, regional 00 UTC soundings sampled very dry boundary-layer conditions across NM and western TX. This dry air mass will spread to the east/northeast through the afternoon as southwesterly winds increase in tandem with a deepening lee trough. Widespread RH values in the low teens to low 20s will likely coincide with 15-20 mph winds (gusting to 25-30 mph). Elevated fire weather conditions will likely be widespread across the southern High Plains into western TX, OK, and KS. However, rainfall over the past 72 hours across parts of TX and OK has limited fuel receptiveness based on recent rainfall analyses and fuel reports. Early spring green up is also more prevalent with eastern extent, which will further limit fire potential. Therefore, the Elevated risk area delineates where the best overlap of dry fine fuels and dry/windy conditions should occur. ...Upper Mississippi Valley... Southerly winds are expected to strengthen through the day in response to the deepening lee trough. Very limited moisture return until late in the day, coupled with strong diurnal warming, should result in areas of 25-35% RH with 15-20 mph winds. Localized elevated fire weather conditions will be possible across parts of IA, MN, and southwestern WI, but are expected to remain sufficiently limited spatially and temporally to negate the need for additional highlights. ...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 1049 AM CDT Sat Apr 13 2024 Valid 131700Z - 141200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF CENTRAL KANSAS... Critical fire weather appears probable along the western fringe of greater surface moisture across eastern Kansas. Here, RH of near to just below 20% is likely along with low-level pressure gradients remaining strong enough into the afternoon to support around 20 mph winds with higher gusts. ..Wendt.. 04/13/2024 .PREV DISCUSSION... /ISSUED 0111 AM CDT Sat Apr 13 2024/ ...Synopsis... Elevated fire weather conditions are anticipated across a broad swath of the southern Great Basin to the southern/central Plains this afternoon. However, the fire weather threat will likely be focused primarily across portions of the southern High Plains where the overlap of receptive fuels and dry/windy conditions will be greatest. ...Southern High Plains to northern KS... 05 UTC surface observations show somewhat poor overnight RH recover with RH values remaining in the 15-30% range across eastern NM into far western TX. Additionally, regional 00 UTC soundings sampled very dry boundary-layer conditions across NM and western TX. This dry air mass will spread to the east/northeast through the afternoon as southwesterly winds increase in tandem with a deepening lee trough. Widespread RH values in the low teens to low 20s will likely coincide with 15-20 mph winds (gusting to 25-30 mph). Elevated fire weather conditions will likely be widespread across the southern High Plains into western TX, OK, and KS. However, rainfall over the past 72 hours across parts of TX and OK has limited fuel receptiveness based on recent rainfall analyses and fuel reports. Early spring green up is also more prevalent with eastern extent, which will further limit fire potential. Therefore, the Elevated risk area delineates where the best overlap of dry fine fuels and dry/windy conditions should occur. ...Upper Mississippi Valley... Southerly winds are expected to strengthen through the day in response to the deepening lee trough. Very limited moisture return until late in the day, coupled with strong diurnal warming, should result in areas of 25-35% RH with 15-20 mph winds. Localized elevated fire weather conditions will be possible across parts of IA, MN, and southwestern WI, but are expected to remain sufficiently limited spatially and temporally to negate the need for additional highlights. ...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 1049 AM CDT Sat Apr 13 2024 Valid 131700Z - 141200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF CENTRAL KANSAS... Critical fire weather appears probable along the western fringe of greater surface moisture across eastern Kansas. Here, RH of near to just below 20% is likely along with low-level pressure gradients remaining strong enough into the afternoon to support around 20 mph winds with higher gusts. ..Wendt.. 04/13/2024 .PREV DISCUSSION... /ISSUED 0111 AM CDT Sat Apr 13 2024/ ...Synopsis... Elevated fire weather conditions are anticipated across a broad swath of the southern Great Basin to the southern/central Plains this afternoon. However, the fire weather threat will likely be focused primarily across portions of the southern High Plains where the overlap of receptive fuels and dry/windy conditions will be greatest. ...Southern High Plains to northern KS... 05 UTC surface observations show somewhat poor overnight RH recover with RH values remaining in the 15-30% range across eastern NM into far western TX. Additionally, regional 00 UTC soundings sampled very dry boundary-layer conditions across NM and western TX. This dry air mass will spread to the east/northeast through the afternoon as southwesterly winds increase in tandem with a deepening lee trough. Widespread RH values in the low teens to low 20s will likely coincide with 15-20 mph winds (gusting to 25-30 mph). Elevated fire weather conditions will likely be widespread across the southern High Plains into western TX, OK, and KS. However, rainfall over the past 72 hours across parts of TX and OK has limited fuel receptiveness based on recent rainfall analyses and fuel reports. Early spring green up is also more prevalent with eastern extent, which will further limit fire potential. Therefore, the Elevated risk area delineates where the best overlap of dry fine fuels and dry/windy conditions should occur. ...Upper Mississippi Valley... Southerly winds are expected to strengthen through the day in response to the deepening lee trough. Very limited moisture return until late in the day, coupled with strong diurnal warming, should result in areas of 25-35% RH with 15-20 mph winds. Localized elevated fire weather conditions will be possible across parts of IA, MN, and southwestern WI, but are expected to remain sufficiently limited spatially and temporally to negate the need for additional highlights. ...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 1049 AM CDT Sat Apr 13 2024 Valid 131700Z - 141200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF CENTRAL KANSAS... Critical fire weather appears probable along the western fringe of greater surface moisture across eastern Kansas. Here, RH of near to just below 20% is likely along with low-level pressure gradients remaining strong enough into the afternoon to support around 20 mph winds with higher gusts. ..Wendt.. 04/13/2024 .PREV DISCUSSION... /ISSUED 0111 AM CDT Sat Apr 13 2024/ ...Synopsis... Elevated fire weather conditions are anticipated across a broad swath of the southern Great Basin to the southern/central Plains this afternoon. However, the fire weather threat will likely be focused primarily across portions of the southern High Plains where the overlap of receptive fuels and dry/windy conditions will be greatest. ...Southern High Plains to northern KS... 05 UTC surface observations show somewhat poor overnight RH recover with RH values remaining in the 15-30% range across eastern NM into far western TX. Additionally, regional 00 UTC soundings sampled very dry boundary-layer conditions across NM and western TX. This dry air mass will spread to the east/northeast through the afternoon as southwesterly winds increase in tandem with a deepening lee trough. Widespread RH values in the low teens to low 20s will likely coincide with 15-20 mph winds (gusting to 25-30 mph). Elevated fire weather conditions will likely be widespread across the southern High Plains into western TX, OK, and KS. However, rainfall over the past 72 hours across parts of TX and OK has limited fuel receptiveness based on recent rainfall analyses and fuel reports. Early spring green up is also more prevalent with eastern extent, which will further limit fire potential. Therefore, the Elevated risk area delineates where the best overlap of dry fine fuels and dry/windy conditions should occur. ...Upper Mississippi Valley... Southerly winds are expected to strengthen through the day in response to the deepening lee trough. Very limited moisture return until late in the day, coupled with strong diurnal warming, should result in areas of 25-35% RH with 15-20 mph winds. Localized elevated fire weather conditions will be possible across parts of IA, MN, and southwestern WI, but are expected to remain sufficiently limited spatially and temporally to negate the need for additional highlights. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0730 AM CDT Sat Apr 13 2024 Valid 131300Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF OREGON... ...SUMMARY... Thunderstorms with isolated severe hail and strong wind gusts will be possible this afternoon and early evening across parts of Oregon. ...Oregon... An upper low off the coast of northern CA this morning will move slowly east-southeastward today towards central CA. South- southeasterly low/mid-level flow on the northeast side of this cyclone will help advect modest mid-level moisture and steep lapse rates over OR through this afternoon. With daytime heating, around 500-1000 J/kg of MLCAPE should develop. Thunderstorms that initially form over the higher terrain of central OR around 20-22Z should have some organization, with 30-40 kt of deep-layer shear supporting a mix of multicells and perhaps a marginal supercell or two. Isolated severe hail may occur with the more discrete convection. Occasional strong/gusty winds also appear possible given steep low-level lapse rates and a well-mixed boundary layer (inverted-v type soundings). These thunderstorms should spread north-northwestward through the early evening before gradually weakening with the loss of daytime heating. ...Great Lakes... Isolated thunderstorms may develop this evening and overnight across the Great Lakes region as a weak mid-level shortwave impulse embedded with a northwest flow regime moves southeastward. This activity will likely remain elevated on the northeast periphery of capping associated with an EML extending across much of the Plains and Upper Midwest. Weak MUCAPE is generally expected where convection should occur, which should keep the overall severe threat low. Still, some small hail may occur given the presence of steep mid-level lapse rates and strong deep-layer shear in the cloud-bearing layer. ..Gleason/Grams.. 04/13/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0730 AM CDT Sat Apr 13 2024 Valid 131300Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF OREGON... ...SUMMARY... Thunderstorms with isolated severe hail and strong wind gusts will be possible this afternoon and early evening across parts of Oregon. ...Oregon... An upper low off the coast of northern CA this morning will move slowly east-southeastward today towards central CA. South- southeasterly low/mid-level flow on the northeast side of this cyclone will help advect modest mid-level moisture and steep lapse rates over OR through this afternoon. With daytime heating, around 500-1000 J/kg of MLCAPE should develop. Thunderstorms that initially form over the higher terrain of central OR around 20-22Z should have some organization, with 30-40 kt of deep-layer shear supporting a mix of multicells and perhaps a marginal supercell or two. Isolated severe hail may occur with the more discrete convection. Occasional strong/gusty winds also appear possible given steep low-level lapse rates and a well-mixed boundary layer (inverted-v type soundings). These thunderstorms should spread north-northwestward through the early evening before gradually weakening with the loss of daytime heating. ...Great Lakes... Isolated thunderstorms may develop this evening and overnight across the Great Lakes region as a weak mid-level shortwave impulse embedded with a northwest flow regime moves southeastward. This activity will likely remain elevated on the northeast periphery of capping associated with an EML extending across much of the Plains and Upper Midwest. Weak MUCAPE is generally expected where convection should occur, which should keep the overall severe threat low. Still, some small hail may occur given the presence of steep mid-level lapse rates and strong deep-layer shear in the cloud-bearing layer. ..Gleason/Grams.. 04/13/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0730 AM CDT Sat Apr 13 2024 Valid 131300Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF OREGON... ...SUMMARY... Thunderstorms with isolated severe hail and strong wind gusts will be possible this afternoon and early evening across parts of Oregon. ...Oregon... An upper low off the coast of northern CA this morning will move slowly east-southeastward today towards central CA. South- southeasterly low/mid-level flow on the northeast side of this cyclone will help advect modest mid-level moisture and steep lapse rates over OR through this afternoon. With daytime heating, around 500-1000 J/kg of MLCAPE should develop. Thunderstorms that initially form over the higher terrain of central OR around 20-22Z should have some organization, with 30-40 kt of deep-layer shear supporting a mix of multicells and perhaps a marginal supercell or two. Isolated severe hail may occur with the more discrete convection. Occasional strong/gusty winds also appear possible given steep low-level lapse rates and a well-mixed boundary layer (inverted-v type soundings). These thunderstorms should spread north-northwestward through the early evening before gradually weakening with the loss of daytime heating. ...Great Lakes... Isolated thunderstorms may develop this evening and overnight across the Great Lakes region as a weak mid-level shortwave impulse embedded with a northwest flow regime moves southeastward. This activity will likely remain elevated on the northeast periphery of capping associated with an EML extending across much of the Plains and Upper Midwest. Weak MUCAPE is generally expected where convection should occur, which should keep the overall severe threat low. Still, some small hail may occur given the presence of steep mid-level lapse rates and strong deep-layer shear in the cloud-bearing layer. ..Gleason/Grams.. 04/13/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0730 AM CDT Sat Apr 13 2024 Valid 131300Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF OREGON... ...SUMMARY... Thunderstorms with isolated severe hail and strong wind gusts will be possible this afternoon and early evening across parts of Oregon. ...Oregon... An upper low off the coast of northern CA this morning will move slowly east-southeastward today towards central CA. South- southeasterly low/mid-level flow on the northeast side of this cyclone will help advect modest mid-level moisture and steep lapse rates over OR through this afternoon. With daytime heating, around 500-1000 J/kg of MLCAPE should develop. Thunderstorms that initially form over the higher terrain of central OR around 20-22Z should have some organization, with 30-40 kt of deep-layer shear supporting a mix of multicells and perhaps a marginal supercell or two. Isolated severe hail may occur with the more discrete convection. Occasional strong/gusty winds also appear possible given steep low-level lapse rates and a well-mixed boundary layer (inverted-v type soundings). These thunderstorms should spread north-northwestward through the early evening before gradually weakening with the loss of daytime heating. ...Great Lakes... Isolated thunderstorms may develop this evening and overnight across the Great Lakes region as a weak mid-level shortwave impulse embedded with a northwest flow regime moves southeastward. This activity will likely remain elevated on the northeast periphery of capping associated with an EML extending across much of the Plains and Upper Midwest. Weak MUCAPE is generally expected where convection should occur, which should keep the overall severe threat low. Still, some small hail may occur given the presence of steep mid-level lapse rates and strong deep-layer shear in the cloud-bearing layer. ..Gleason/Grams.. 04/13/2024 Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0358 AM CDT Sat Apr 13 2024 Valid 161200Z - 211200Z ...DISCUSSION... ...D4/Tuesday... A deep surface cyclone over the central Great Plains at 12Z Tuesday should gradually progress east-northeast to the Upper MS Valley by early Wednesday. An intense mid-level jetlet (in excess of 80 kts) from northwest TX into southern KS should move east across the Ozark Plateau before weakening Tuesday night as it reaches the Lower OH Valley. The initially north/south-oriented cold front to the south of the surface low will move farther east faster near the cyclone, but slow and stall farther south over the Ark-La-Tex. Synoptically, two favored regions for severe storms Tuesday afternoon/evening will be within the left-exit region of the intense mid-level jet in parts of IA/MO/IL, and over the Ark-La-Tex into the Mid-South where frontal convection will intersect with the richer low-level moisture plume emanating north from the western Gulf. A broad severe weather highlight remains warranted, with areas of higher probabilities likely being needed in later outlooks as mesoscale details become clearer given that the instability/buoyancy plume should be confined and modulated by late D3-early D4 convection. ...D5/Wednesday... Latest guidance suggest some severe threat should persist into early D5 given the strength of low to mid-level flow before the deep surface cyclone occludes and dampens over the Great Lakes. The northeast lobe of the warm-moist sector emanating from the western Gulf should be further confined relative to D4. Conditionally, the central OH Valley vicinity appears to have the best opportunity to destabilize in the wake of late D4-early D5 convection and overlap with the stronger flow fields. This area will be monitored for a possible severe weather highlight in the next outlook cycle. ...D6/Thursday... With a broad upper trough becoming established over the Upper Midwest, a building surface anticyclone over the Great Plains should support a reinforcing cold front impinging on the rich western Gulf moisture plume over parts of TX into AR/LA. Some severe potential may evolve given increasingly larger CAPE compared to prior days, but overall shear profiles appear modest. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0358 AM CDT Sat Apr 13 2024 Valid 161200Z - 211200Z ...DISCUSSION... ...D4/Tuesday... A deep surface cyclone over the central Great Plains at 12Z Tuesday should gradually progress east-northeast to the Upper MS Valley by early Wednesday. An intense mid-level jetlet (in excess of 80 kts) from northwest TX into southern KS should move east across the Ozark Plateau before weakening Tuesday night as it reaches the Lower OH Valley. The initially north/south-oriented cold front to the south of the surface low will move farther east faster near the cyclone, but slow and stall farther south over the Ark-La-Tex. Synoptically, two favored regions for severe storms Tuesday afternoon/evening will be within the left-exit region of the intense mid-level jet in parts of IA/MO/IL, and over the Ark-La-Tex into the Mid-South where frontal convection will intersect with the richer low-level moisture plume emanating north from the western Gulf. A broad severe weather highlight remains warranted, with areas of higher probabilities likely being needed in later outlooks as mesoscale details become clearer given that the instability/buoyancy plume should be confined and modulated by late D3-early D4 convection. ...D5/Wednesday... Latest guidance suggest some severe threat should persist into early D5 given the strength of low to mid-level flow before the deep surface cyclone occludes and dampens over the Great Lakes. The northeast lobe of the warm-moist sector emanating from the western Gulf should be further confined relative to D4. Conditionally, the central OH Valley vicinity appears to have the best opportunity to destabilize in the wake of late D4-early D5 convection and overlap with the stronger flow fields. This area will be monitored for a possible severe weather highlight in the next outlook cycle. ...D6/Thursday... With a broad upper trough becoming established over the Upper Midwest, a building surface anticyclone over the Great Plains should support a reinforcing cold front impinging on the rich western Gulf moisture plume over parts of TX into AR/LA. Some severe potential may evolve given increasingly larger CAPE compared to prior days, but overall shear profiles appear modest. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0358 AM CDT Sat Apr 13 2024 Valid 161200Z - 211200Z ...DISCUSSION... ...D4/Tuesday... A deep surface cyclone over the central Great Plains at 12Z Tuesday should gradually progress east-northeast to the Upper MS Valley by early Wednesday. An intense mid-level jetlet (in excess of 80 kts) from northwest TX into southern KS should move east across the Ozark Plateau before weakening Tuesday night as it reaches the Lower OH Valley. The initially north/south-oriented cold front to the south of the surface low will move farther east faster near the cyclone, but slow and stall farther south over the Ark-La-Tex. Synoptically, two favored regions for severe storms Tuesday afternoon/evening will be within the left-exit region of the intense mid-level jet in parts of IA/MO/IL, and over the Ark-La-Tex into the Mid-South where frontal convection will intersect with the richer low-level moisture plume emanating north from the western Gulf. A broad severe weather highlight remains warranted, with areas of higher probabilities likely being needed in later outlooks as mesoscale details become clearer given that the instability/buoyancy plume should be confined and modulated by late D3-early D4 convection. ...D5/Wednesday... Latest guidance suggest some severe threat should persist into early D5 given the strength of low to mid-level flow before the deep surface cyclone occludes and dampens over the Great Lakes. The northeast lobe of the warm-moist sector emanating from the western Gulf should be further confined relative to D4. Conditionally, the central OH Valley vicinity appears to have the best opportunity to destabilize in the wake of late D4-early D5 convection and overlap with the stronger flow fields. This area will be monitored for a possible severe weather highlight in the next outlook cycle. ...D6/Thursday... With a broad upper trough becoming established over the Upper Midwest, a building surface anticyclone over the Great Plains should support a reinforcing cold front impinging on the rich western Gulf moisture plume over parts of TX into AR/LA. Some severe potential may evolve given increasingly larger CAPE compared to prior days, but overall shear profiles appear modest. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0358 AM CDT Sat Apr 13 2024 Valid 161200Z - 211200Z ...DISCUSSION... ...D4/Tuesday... A deep surface cyclone over the central Great Plains at 12Z Tuesday should gradually progress east-northeast to the Upper MS Valley by early Wednesday. An intense mid-level jetlet (in excess of 80 kts) from northwest TX into southern KS should move east across the Ozark Plateau before weakening Tuesday night as it reaches the Lower OH Valley. The initially north/south-oriented cold front to the south of the surface low will move farther east faster near the cyclone, but slow and stall farther south over the Ark-La-Tex. Synoptically, two favored regions for severe storms Tuesday afternoon/evening will be within the left-exit region of the intense mid-level jet in parts of IA/MO/IL, and over the Ark-La-Tex into the Mid-South where frontal convection will intersect with the richer low-level moisture plume emanating north from the western Gulf. A broad severe weather highlight remains warranted, with areas of higher probabilities likely being needed in later outlooks as mesoscale details become clearer given that the instability/buoyancy plume should be confined and modulated by late D3-early D4 convection. ...D5/Wednesday... Latest guidance suggest some severe threat should persist into early D5 given the strength of low to mid-level flow before the deep surface cyclone occludes and dampens over the Great Lakes. The northeast lobe of the warm-moist sector emanating from the western Gulf should be further confined relative to D4. Conditionally, the central OH Valley vicinity appears to have the best opportunity to destabilize in the wake of late D4-early D5 convection and overlap with the stronger flow fields. This area will be monitored for a possible severe weather highlight in the next outlook cycle. ...D6/Thursday... With a broad upper trough becoming established over the Upper Midwest, a building surface anticyclone over the Great Plains should support a reinforcing cold front impinging on the rich western Gulf moisture plume over parts of TX into AR/LA. Some severe potential may evolve given increasingly larger CAPE compared to prior days, but overall shear profiles appear modest. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0358 AM CDT Sat Apr 13 2024 Valid 161200Z - 211200Z ...DISCUSSION... ...D4/Tuesday... A deep surface cyclone over the central Great Plains at 12Z Tuesday should gradually progress east-northeast to the Upper MS Valley by early Wednesday. An intense mid-level jetlet (in excess of 80 kts) from northwest TX into southern KS should move east across the Ozark Plateau before weakening Tuesday night as it reaches the Lower OH Valley. The initially north/south-oriented cold front to the south of the surface low will move farther east faster near the cyclone, but slow and stall farther south over the Ark-La-Tex. Synoptically, two favored regions for severe storms Tuesday afternoon/evening will be within the left-exit region of the intense mid-level jet in parts of IA/MO/IL, and over the Ark-La-Tex into the Mid-South where frontal convection will intersect with the richer low-level moisture plume emanating north from the western Gulf. A broad severe weather highlight remains warranted, with areas of higher probabilities likely being needed in later outlooks as mesoscale details become clearer given that the instability/buoyancy plume should be confined and modulated by late D3-early D4 convection. ...D5/Wednesday... Latest guidance suggest some severe threat should persist into early D5 given the strength of low to mid-level flow before the deep surface cyclone occludes and dampens over the Great Lakes. The northeast lobe of the warm-moist sector emanating from the western Gulf should be further confined relative to D4. Conditionally, the central OH Valley vicinity appears to have the best opportunity to destabilize in the wake of late D4-early D5 convection and overlap with the stronger flow fields. This area will be monitored for a possible severe weather highlight in the next outlook cycle. ...D6/Thursday... With a broad upper trough becoming established over the Upper Midwest, a building surface anticyclone over the Great Plains should support a reinforcing cold front impinging on the rich western Gulf moisture plume over parts of TX into AR/LA. Some severe potential may evolve given increasingly larger CAPE compared to prior days, but overall shear profiles appear modest. Read more