SPC Apr 17, 2024 0730 UTC Day 3 Severe Thunderstorm Outlook

1 year 3 months ago
SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 AM CDT Wed Apr 17 2024 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM NORTH CAROLINA INTO NORTHERN GEORGIA AND ALABAMA... ...SUMMARY... Sporadic strong to marginally severe storms are possible on Friday over parts of the Southeast. ...Synopsis... A large but low-amplitude upper trough will exist from the northern Rockies east across the northern Plains, upper MS Valley, and Great Lakes, with an upper low deepening over Ontario. Moderate midlevel westerlies will exist across much of the Plains into the OH Valley, with much weaker winds aloft from TX into the Southeast. Meanwhile, a weaker wave is expected to move across parts of the Southwest early on Saturday. At the surface, high pressure will be prominent across the central and northern Plains as well as the MS and OH Valleys, with a cold front roughly stretching from central TX to the Appalachians. A moist air mass will exist south of this front, from TX eastward across the Gulf Coast states. Given a strong area of high pressure to the north, this front should continue to progress generally southward through the period. ...The Frontal Zone from TX to the Carolinas... Scattered thunderstorms may linger from OH into eastern TN Friday morning near the front, with generally weak instability at that time and no severe threat expected. Other storms will form as heating occurs and the front interacts with moisture over the Carolinas. Around 1000 J/kg MLCAPE appears reasonable, beneath modest west/northwest flow aloft. Forecast soundings depict a deeply mixed boundary layer conducive for strong gusts while hodographs appear sufficiently long for cellular storm mode, and thus marginal hail risk. This threat should extend westward across parts of GA and AL near the front as well for daytime isolated severe wind or hail. Farther west, a large area of elevated instability will exist over the southern Plains, well north of the surface front from eastern TX to the middle Rio Grande Valley. Overall lift is expected to be weak in this region, with lesser heating potential and weak shear. The greatest chance of general thunderstorms here may be overnight near the 850 mb boundary from southwest TX to the Red River. Small hail cannot be ruled out given ample elevated CAPE. ..Jewell.. 04/17/2024 Read more

SPC Apr 17, 2024 0730 UTC Day 3 Severe Thunderstorm Outlook

1 year 3 months ago
SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 AM CDT Wed Apr 17 2024 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM NORTH CAROLINA INTO NORTHERN GEORGIA AND ALABAMA... ...SUMMARY... Sporadic strong to marginally severe storms are possible on Friday over parts of the Southeast. ...Synopsis... A large but low-amplitude upper trough will exist from the northern Rockies east across the northern Plains, upper MS Valley, and Great Lakes, with an upper low deepening over Ontario. Moderate midlevel westerlies will exist across much of the Plains into the OH Valley, with much weaker winds aloft from TX into the Southeast. Meanwhile, a weaker wave is expected to move across parts of the Southwest early on Saturday. At the surface, high pressure will be prominent across the central and northern Plains as well as the MS and OH Valleys, with a cold front roughly stretching from central TX to the Appalachians. A moist air mass will exist south of this front, from TX eastward across the Gulf Coast states. Given a strong area of high pressure to the north, this front should continue to progress generally southward through the period. ...The Frontal Zone from TX to the Carolinas... Scattered thunderstorms may linger from OH into eastern TN Friday morning near the front, with generally weak instability at that time and no severe threat expected. Other storms will form as heating occurs and the front interacts with moisture over the Carolinas. Around 1000 J/kg MLCAPE appears reasonable, beneath modest west/northwest flow aloft. Forecast soundings depict a deeply mixed boundary layer conducive for strong gusts while hodographs appear sufficiently long for cellular storm mode, and thus marginal hail risk. This threat should extend westward across parts of GA and AL near the front as well for daytime isolated severe wind or hail. Farther west, a large area of elevated instability will exist over the southern Plains, well north of the surface front from eastern TX to the middle Rio Grande Valley. Overall lift is expected to be weak in this region, with lesser heating potential and weak shear. The greatest chance of general thunderstorms here may be overnight near the 850 mb boundary from southwest TX to the Red River. Small hail cannot be ruled out given ample elevated CAPE. ..Jewell.. 04/17/2024 Read more

SPC Apr 17, 2024 0730 UTC Day 3 Severe Thunderstorm Outlook

1 year 3 months ago
SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 AM CDT Wed Apr 17 2024 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM NORTH CAROLINA INTO NORTHERN GEORGIA AND ALABAMA... ...SUMMARY... Sporadic strong to marginally severe storms are possible on Friday over parts of the Southeast. ...Synopsis... A large but low-amplitude upper trough will exist from the northern Rockies east across the northern Plains, upper MS Valley, and Great Lakes, with an upper low deepening over Ontario. Moderate midlevel westerlies will exist across much of the Plains into the OH Valley, with much weaker winds aloft from TX into the Southeast. Meanwhile, a weaker wave is expected to move across parts of the Southwest early on Saturday. At the surface, high pressure will be prominent across the central and northern Plains as well as the MS and OH Valleys, with a cold front roughly stretching from central TX to the Appalachians. A moist air mass will exist south of this front, from TX eastward across the Gulf Coast states. Given a strong area of high pressure to the north, this front should continue to progress generally southward through the period. ...The Frontal Zone from TX to the Carolinas... Scattered thunderstorms may linger from OH into eastern TN Friday morning near the front, with generally weak instability at that time and no severe threat expected. Other storms will form as heating occurs and the front interacts with moisture over the Carolinas. Around 1000 J/kg MLCAPE appears reasonable, beneath modest west/northwest flow aloft. Forecast soundings depict a deeply mixed boundary layer conducive for strong gusts while hodographs appear sufficiently long for cellular storm mode, and thus marginal hail risk. This threat should extend westward across parts of GA and AL near the front as well for daytime isolated severe wind or hail. Farther west, a large area of elevated instability will exist over the southern Plains, well north of the surface front from eastern TX to the middle Rio Grande Valley. Overall lift is expected to be weak in this region, with lesser heating potential and weak shear. The greatest chance of general thunderstorms here may be overnight near the 850 mb boundary from southwest TX to the Red River. Small hail cannot be ruled out given ample elevated CAPE. ..Jewell.. 04/17/2024 Read more

SPC Apr 17, 2024 0730 UTC Day 3 Severe Thunderstorm Outlook

1 year 3 months ago
SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 AM CDT Wed Apr 17 2024 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM NORTH CAROLINA INTO NORTHERN GEORGIA AND ALABAMA... ...SUMMARY... Sporadic strong to marginally severe storms are possible on Friday over parts of the Southeast. ...Synopsis... A large but low-amplitude upper trough will exist from the northern Rockies east across the northern Plains, upper MS Valley, and Great Lakes, with an upper low deepening over Ontario. Moderate midlevel westerlies will exist across much of the Plains into the OH Valley, with much weaker winds aloft from TX into the Southeast. Meanwhile, a weaker wave is expected to move across parts of the Southwest early on Saturday. At the surface, high pressure will be prominent across the central and northern Plains as well as the MS and OH Valleys, with a cold front roughly stretching from central TX to the Appalachians. A moist air mass will exist south of this front, from TX eastward across the Gulf Coast states. Given a strong area of high pressure to the north, this front should continue to progress generally southward through the period. ...The Frontal Zone from TX to the Carolinas... Scattered thunderstorms may linger from OH into eastern TN Friday morning near the front, with generally weak instability at that time and no severe threat expected. Other storms will form as heating occurs and the front interacts with moisture over the Carolinas. Around 1000 J/kg MLCAPE appears reasonable, beneath modest west/northwest flow aloft. Forecast soundings depict a deeply mixed boundary layer conducive for strong gusts while hodographs appear sufficiently long for cellular storm mode, and thus marginal hail risk. This threat should extend westward across parts of GA and AL near the front as well for daytime isolated severe wind or hail. Farther west, a large area of elevated instability will exist over the southern Plains, well north of the surface front from eastern TX to the middle Rio Grande Valley. Overall lift is expected to be weak in this region, with lesser heating potential and weak shear. The greatest chance of general thunderstorms here may be overnight near the 850 mb boundary from southwest TX to the Red River. Small hail cannot be ruled out given ample elevated CAPE. ..Jewell.. 04/17/2024 Read more

SPC Day 2 Fire Weather Outlook

1 year 3 months ago
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0153 AM CDT Wed Apr 17 2024 Valid 181200Z - 191200Z ...NO CRITICAL AREAS... ...Synopsis... Predominately zonal mid-level flow is expected over the CONUS by D2/Thursday. Stronger westerly flow is expected to gradually shift east as weak high pressure builds over the West. At the surface, a cold front is forecast to move across much of the plains ushering in a cooler air mass. Surface high pressure behind the front should keep winds modest over much of the central US. The only exception to this may be across parts of far northeast NM and southern CO. Here, the dry air mass may remain sheltered from the cold front supporting at least brief localized fire-weather conditions D2/Thursday afternoon. Otherwise, fire-weather potential appears limited across the CONUS. ..Lyons.. 04/17/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook

1 year 3 months ago
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0153 AM CDT Wed Apr 17 2024 Valid 181200Z - 191200Z ...NO CRITICAL AREAS... ...Synopsis... Predominately zonal mid-level flow is expected over the CONUS by D2/Thursday. Stronger westerly flow is expected to gradually shift east as weak high pressure builds over the West. At the surface, a cold front is forecast to move across much of the plains ushering in a cooler air mass. Surface high pressure behind the front should keep winds modest over much of the central US. The only exception to this may be across parts of far northeast NM and southern CO. Here, the dry air mass may remain sheltered from the cold front supporting at least brief localized fire-weather conditions D2/Thursday afternoon. Otherwise, fire-weather potential appears limited across the CONUS. ..Lyons.. 04/17/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook

1 year 3 months ago
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0153 AM CDT Wed Apr 17 2024 Valid 181200Z - 191200Z ...NO CRITICAL AREAS... ...Synopsis... Predominately zonal mid-level flow is expected over the CONUS by D2/Thursday. Stronger westerly flow is expected to gradually shift east as weak high pressure builds over the West. At the surface, a cold front is forecast to move across much of the plains ushering in a cooler air mass. Surface high pressure behind the front should keep winds modest over much of the central US. The only exception to this may be across parts of far northeast NM and southern CO. Here, the dry air mass may remain sheltered from the cold front supporting at least brief localized fire-weather conditions D2/Thursday afternoon. Otherwise, fire-weather potential appears limited across the CONUS. ..Lyons.. 04/17/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook

1 year 3 months ago
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0153 AM CDT Wed Apr 17 2024 Valid 181200Z - 191200Z ...NO CRITICAL AREAS... ...Synopsis... Predominately zonal mid-level flow is expected over the CONUS by D2/Thursday. Stronger westerly flow is expected to gradually shift east as weak high pressure builds over the West. At the surface, a cold front is forecast to move across much of the plains ushering in a cooler air mass. Surface high pressure behind the front should keep winds modest over much of the central US. The only exception to this may be across parts of far northeast NM and southern CO. Here, the dry air mass may remain sheltered from the cold front supporting at least brief localized fire-weather conditions D2/Thursday afternoon. Otherwise, fire-weather potential appears limited across the CONUS. ..Lyons.. 04/17/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook

1 year 3 months ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0151 AM CDT Wed Apr 17 2024 Valid 171200Z - 181200Z ...Synopsis... Behind the weakening upper low, flow aloft is forecast to trend more zonal and weaken as the general pattern de-amplifies. Still, some stronger westerly flow will linger over parts of the southern Rockies through the forecast period. A lee low will bolster low-level surface flow off the Rockies and into the adjacent High Plains this afternoon and evening. Warm temperatures are expected along with the dry downslope flow. This should support afternoon min RH values of 10-15% across much of eastern NM and southern CO. While winds are not expected to be overly strong (generally 10-15 mph) a few hours of dry and breezy conditions are possible. With area fuels dry, elevated fire-weather conditions are likely. ..Lyons.. 04/17/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook

1 year 3 months ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0151 AM CDT Wed Apr 17 2024 Valid 171200Z - 181200Z ...Synopsis... Behind the weakening upper low, flow aloft is forecast to trend more zonal and weaken as the general pattern de-amplifies. Still, some stronger westerly flow will linger over parts of the southern Rockies through the forecast period. A lee low will bolster low-level surface flow off the Rockies and into the adjacent High Plains this afternoon and evening. Warm temperatures are expected along with the dry downslope flow. This should support afternoon min RH values of 10-15% across much of eastern NM and southern CO. While winds are not expected to be overly strong (generally 10-15 mph) a few hours of dry and breezy conditions are possible. With area fuels dry, elevated fire-weather conditions are likely. ..Lyons.. 04/17/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook

1 year 3 months ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0151 AM CDT Wed Apr 17 2024 Valid 171200Z - 181200Z ...Synopsis... Behind the weakening upper low, flow aloft is forecast to trend more zonal and weaken as the general pattern de-amplifies. Still, some stronger westerly flow will linger over parts of the southern Rockies through the forecast period. A lee low will bolster low-level surface flow off the Rockies and into the adjacent High Plains this afternoon and evening. Warm temperatures are expected along with the dry downslope flow. This should support afternoon min RH values of 10-15% across much of eastern NM and southern CO. While winds are not expected to be overly strong (generally 10-15 mph) a few hours of dry and breezy conditions are possible. With area fuels dry, elevated fire-weather conditions are likely. ..Lyons.. 04/17/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook

1 year 3 months ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0151 AM CDT Wed Apr 17 2024 Valid 171200Z - 181200Z ...Synopsis... Behind the weakening upper low, flow aloft is forecast to trend more zonal and weaken as the general pattern de-amplifies. Still, some stronger westerly flow will linger over parts of the southern Rockies through the forecast period. A lee low will bolster low-level surface flow off the Rockies and into the adjacent High Plains this afternoon and evening. Warm temperatures are expected along with the dry downslope flow. This should support afternoon min RH values of 10-15% across much of eastern NM and southern CO. While winds are not expected to be overly strong (generally 10-15 mph) a few hours of dry and breezy conditions are possible. With area fuels dry, elevated fire-weather conditions are likely. ..Lyons.. 04/17/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Apr 17, 2024 0600 UTC Day 2 Convective Outlook

1 year 3 months ago
SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1258 AM CDT Wed Apr 17 2024 Valid 181200Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE MID MISSISSIPPI VALLEY AND LOWER OHIO VALLEY...AND OVER A PORTION OF NORTHERN TEXAS... ...SUMMARY... Scattered strong to severe storms capable of damaging winds, large hail, and perhaps a couple tornadoes will be possible Thursday from parts of eastern Missouri into the lower Ohio Valley and vicinity. Locally damaging winds and hail are also expected over parts of northern Texas. ...Synopsis... On Thursday, an upper low will move east from Manitoba into western Ontario, with a broad area of cyclonic flow aloft from the northern Plains to the Upper Great Lakes. South of the primary midlevel temperature gradient, moderate winds to around 50 kt will extend southward from MO into the OH Valley, with 30 kt midlevel winds into northern TX. Southwest winds of 30-40 kt will exist around 850 mb, aiding theta-e advection into the Mid MS/OH Valleys. At the surface, a cold front will exist roughly from northern MO into northwest TX Thursday morning, with a weak low moving from MO into the OH Valley ahead off the front. A warm front will lift northward ahead of the low, allowing moistening to occur over much of southern IL, IN, and northern KY during the day, and spreading into western OH overnight. Ample moisture ahead of this front will result in an elongated area of strong to severe potential throughout the day. ...Mid MS Valley into the lower OH Valley... Severe probabilities have been shifted farther west given latest model trends, as strong to severe storms could begin rather early in the day. Ongoing areas of storms are expected on the nose of the low-level jet, possibly in the form of an MCS, roughly over northern MO. As the warm front lifts north ahead of any such system, this could prove favorable for a swath of damaging winds. Otherwise, activity is expected to form near the low and along the cold front, where instability and shear will also favor supercells with large hail and perhaps tornado risk. Given the potential for early storms, this lends uncertainty to the forecast, and precludes an upgrade of higher coverage probabilities as placement would be uncertain. Regardless of early day evolution, moderate westerlies atop the expanding moist sector should favor areas of damaging wind, hail, and perhaps a few tornadoes during the day and through early evening. The severe risk could potentially reach into western OH and northern KY late, depending on upstream evolution. ...Northern TX... A cold front will push quickly south across OK and MO during the day, and across the Red River during the late afternoon and early evening. Given the late frontal arrival, strong destabilization will occur with full heating and upper 60s to lower 70s F dewpoints. MLCAPE over 3000 J/kg is forecast, with steep lapse rates through a deep layer. Although shear will not be strong, hodographs will favor southeastward-moving cells developing near the front or within the narrow low-level lapse rate plume where it will become uncapped. Locally damaging downbursts along with hail will be possible with any storms that develop, warranting an upgrade in severe probabilities for this focused diurnal event. ..Jewell.. 04/17/2024 Read more

SPC Apr 17, 2024 0600 UTC Day 2 Convective Outlook

1 year 3 months ago
SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1258 AM CDT Wed Apr 17 2024 Valid 181200Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE MID MISSISSIPPI VALLEY AND LOWER OHIO VALLEY...AND OVER A PORTION OF NORTHERN TEXAS... ...SUMMARY... Scattered strong to severe storms capable of damaging winds, large hail, and perhaps a couple tornadoes will be possible Thursday from parts of eastern Missouri into the lower Ohio Valley and vicinity. Locally damaging winds and hail are also expected over parts of northern Texas. ...Synopsis... On Thursday, an upper low will move east from Manitoba into western Ontario, with a broad area of cyclonic flow aloft from the northern Plains to the Upper Great Lakes. South of the primary midlevel temperature gradient, moderate winds to around 50 kt will extend southward from MO into the OH Valley, with 30 kt midlevel winds into northern TX. Southwest winds of 30-40 kt will exist around 850 mb, aiding theta-e advection into the Mid MS/OH Valleys. At the surface, a cold front will exist roughly from northern MO into northwest TX Thursday morning, with a weak low moving from MO into the OH Valley ahead off the front. A warm front will lift northward ahead of the low, allowing moistening to occur over much of southern IL, IN, and northern KY during the day, and spreading into western OH overnight. Ample moisture ahead of this front will result in an elongated area of strong to severe potential throughout the day. ...Mid MS Valley into the lower OH Valley... Severe probabilities have been shifted farther west given latest model trends, as strong to severe storms could begin rather early in the day. Ongoing areas of storms are expected on the nose of the low-level jet, possibly in the form of an MCS, roughly over northern MO. As the warm front lifts north ahead of any such system, this could prove favorable for a swath of damaging winds. Otherwise, activity is expected to form near the low and along the cold front, where instability and shear will also favor supercells with large hail and perhaps tornado risk. Given the potential for early storms, this lends uncertainty to the forecast, and precludes an upgrade of higher coverage probabilities as placement would be uncertain. Regardless of early day evolution, moderate westerlies atop the expanding moist sector should favor areas of damaging wind, hail, and perhaps a few tornadoes during the day and through early evening. The severe risk could potentially reach into western OH and northern KY late, depending on upstream evolution. ...Northern TX... A cold front will push quickly south across OK and MO during the day, and across the Red River during the late afternoon and early evening. Given the late frontal arrival, strong destabilization will occur with full heating and upper 60s to lower 70s F dewpoints. MLCAPE over 3000 J/kg is forecast, with steep lapse rates through a deep layer. Although shear will not be strong, hodographs will favor southeastward-moving cells developing near the front or within the narrow low-level lapse rate plume where it will become uncapped. Locally damaging downbursts along with hail will be possible with any storms that develop, warranting an upgrade in severe probabilities for this focused diurnal event. ..Jewell.. 04/17/2024 Read more

SPC Apr 17, 2024 0600 UTC Day 2 Convective Outlook

1 year 3 months ago
SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1258 AM CDT Wed Apr 17 2024 Valid 181200Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE MID MISSISSIPPI VALLEY AND LOWER OHIO VALLEY...AND OVER A PORTION OF NORTHERN TEXAS... ...SUMMARY... Scattered strong to severe storms capable of damaging winds, large hail, and perhaps a couple tornadoes will be possible Thursday from parts of eastern Missouri into the lower Ohio Valley and vicinity. Locally damaging winds and hail are also expected over parts of northern Texas. ...Synopsis... On Thursday, an upper low will move east from Manitoba into western Ontario, with a broad area of cyclonic flow aloft from the northern Plains to the Upper Great Lakes. South of the primary midlevel temperature gradient, moderate winds to around 50 kt will extend southward from MO into the OH Valley, with 30 kt midlevel winds into northern TX. Southwest winds of 30-40 kt will exist around 850 mb, aiding theta-e advection into the Mid MS/OH Valleys. At the surface, a cold front will exist roughly from northern MO into northwest TX Thursday morning, with a weak low moving from MO into the OH Valley ahead off the front. A warm front will lift northward ahead of the low, allowing moistening to occur over much of southern IL, IN, and northern KY during the day, and spreading into western OH overnight. Ample moisture ahead of this front will result in an elongated area of strong to severe potential throughout the day. ...Mid MS Valley into the lower OH Valley... Severe probabilities have been shifted farther west given latest model trends, as strong to severe storms could begin rather early in the day. Ongoing areas of storms are expected on the nose of the low-level jet, possibly in the form of an MCS, roughly over northern MO. As the warm front lifts north ahead of any such system, this could prove favorable for a swath of damaging winds. Otherwise, activity is expected to form near the low and along the cold front, where instability and shear will also favor supercells with large hail and perhaps tornado risk. Given the potential for early storms, this lends uncertainty to the forecast, and precludes an upgrade of higher coverage probabilities as placement would be uncertain. Regardless of early day evolution, moderate westerlies atop the expanding moist sector should favor areas of damaging wind, hail, and perhaps a few tornadoes during the day and through early evening. The severe risk could potentially reach into western OH and northern KY late, depending on upstream evolution. ...Northern TX... A cold front will push quickly south across OK and MO during the day, and across the Red River during the late afternoon and early evening. Given the late frontal arrival, strong destabilization will occur with full heating and upper 60s to lower 70s F dewpoints. MLCAPE over 3000 J/kg is forecast, with steep lapse rates through a deep layer. Although shear will not be strong, hodographs will favor southeastward-moving cells developing near the front or within the narrow low-level lapse rate plume where it will become uncapped. Locally damaging downbursts along with hail will be possible with any storms that develop, warranting an upgrade in severe probabilities for this focused diurnal event. ..Jewell.. 04/17/2024 Read more

SPC Apr 17, 2024 0600 UTC Day 2 Convective Outlook

1 year 3 months ago
SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1258 AM CDT Wed Apr 17 2024 Valid 181200Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE MID MISSISSIPPI VALLEY AND LOWER OHIO VALLEY...AND OVER A PORTION OF NORTHERN TEXAS... ...SUMMARY... Scattered strong to severe storms capable of damaging winds, large hail, and perhaps a couple tornadoes will be possible Thursday from parts of eastern Missouri into the lower Ohio Valley and vicinity. Locally damaging winds and hail are also expected over parts of northern Texas. ...Synopsis... On Thursday, an upper low will move east from Manitoba into western Ontario, with a broad area of cyclonic flow aloft from the northern Plains to the Upper Great Lakes. South of the primary midlevel temperature gradient, moderate winds to around 50 kt will extend southward from MO into the OH Valley, with 30 kt midlevel winds into northern TX. Southwest winds of 30-40 kt will exist around 850 mb, aiding theta-e advection into the Mid MS/OH Valleys. At the surface, a cold front will exist roughly from northern MO into northwest TX Thursday morning, with a weak low moving from MO into the OH Valley ahead off the front. A warm front will lift northward ahead of the low, allowing moistening to occur over much of southern IL, IN, and northern KY during the day, and spreading into western OH overnight. Ample moisture ahead of this front will result in an elongated area of strong to severe potential throughout the day. ...Mid MS Valley into the lower OH Valley... Severe probabilities have been shifted farther west given latest model trends, as strong to severe storms could begin rather early in the day. Ongoing areas of storms are expected on the nose of the low-level jet, possibly in the form of an MCS, roughly over northern MO. As the warm front lifts north ahead of any such system, this could prove favorable for a swath of damaging winds. Otherwise, activity is expected to form near the low and along the cold front, where instability and shear will also favor supercells with large hail and perhaps tornado risk. Given the potential for early storms, this lends uncertainty to the forecast, and precludes an upgrade of higher coverage probabilities as placement would be uncertain. Regardless of early day evolution, moderate westerlies atop the expanding moist sector should favor areas of damaging wind, hail, and perhaps a few tornadoes during the day and through early evening. The severe risk could potentially reach into western OH and northern KY late, depending on upstream evolution. ...Northern TX... A cold front will push quickly south across OK and MO during the day, and across the Red River during the late afternoon and early evening. Given the late frontal arrival, strong destabilization will occur with full heating and upper 60s to lower 70s F dewpoints. MLCAPE over 3000 J/kg is forecast, with steep lapse rates through a deep layer. Although shear will not be strong, hodographs will favor southeastward-moving cells developing near the front or within the narrow low-level lapse rate plume where it will become uncapped. Locally damaging downbursts along with hail will be possible with any storms that develop, warranting an upgrade in severe probabilities for this focused diurnal event. ..Jewell.. 04/17/2024 Read more

SPC Apr 17, 2024 0600 UTC Day 1 Convective Outlook

1 year 3 months ago
SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1256 AM CDT Wed Apr 17 2024 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE OHIO VALLEY AND LOWER GREAT LAKES...AND IN PARTS OF NORTHEAST KANSAS AND WESTERN MISSOURI... ...SUMMARY... Scattered thunderstorms, capable of wind damage, isolated large hail and a tornado threat, are expected to develop across parts of the Ohio Valley and Lower Great Lakes this afternoon. Storms with large hail are expected tonight in parts of the central Plains and Ozarks. ...Ohio and Tennessee Valleys/Central Gulf Coast States... A negatively tilted upper-level trough, and an associated surface low, will move into the Great Lakes today. A corridor of maximized surface dewpoints will move eastward across the Ohio Valley today, as a cold front approaches from the west. Scattered thunderstorms will likely develop during the late morning, as low-level convergence and instability increases. These storms, in the form of clusters or short line segments, will move eastward across the Ohio Valley and Lower Great Lakes region during the afternoon. RAP forecast soundings across far eastern Indiana and western Ohio during the early afternoon show a favorable environment for severe storms, with MLCAPE near 1500 J/kg and 0-6 km shear around 50 knots. This should support an isolated large hail threat with the more discrete rotating storms. A wind-damage threat will also be possible, especially with the more organized line segments. Forecast soundings suggest that low-level shear will become more favorable in the late afternoon, with 0-3 km storm-relative helicity increasing into the 225 to 250 m2/s2 range. For this reason, the tornado threat is expected to be greater a bit further east from central and eastern Ohio into far western Pennsylvania. Further south into the Tennessee Valley and central Gulf Coast states, isolated thunderstorms are expected to develop ahead of a cold front, and near a moist axis with surface dewpoints in the 60s F. MLCAPE in the 750 to 1000 J/kg range, along with 0-6 km shear from 40 to 50 knots will be sufficient for an isolated severe threat. Marginally severe wind gusts and hail will be the primary threats. ...Central Plains/Ozarks... An upper-level trough will move through the north-central U.S. tonight, as a 70 to 80 knot mid-level jet passes through the trough. In response, a 40 to 50 knot low-level jet will develop further south across the central Plains. Thunderstorms are expected to initiate near the northern edge of the low-level jet late this evening from central Kansas into far southeast Nebraska. These storms are expected to move eastward across northeast Kansas and into western Missouri. Forecast soundings in northeast Kansas around 06Z have MUCAPE near 2500 J/kg, with effective shear around 45 knots. This, combined with 700-500 mb lapse rates around 7.5 C/km, should be favorable for elevated rotating storms with potential for very large hail. The large hail threat is expected to be greatest in the 04Z to 07Z time window, but may persist through late in the period. ..Broyles/Lyons.. 04/17/2024 Read more

SPC Apr 17, 2024 0600 UTC Day 1 Convective Outlook

1 year 3 months ago
SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1256 AM CDT Wed Apr 17 2024 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE OHIO VALLEY AND LOWER GREAT LAKES...AND IN PARTS OF NORTHEAST KANSAS AND WESTERN MISSOURI... ...SUMMARY... Scattered thunderstorms, capable of wind damage, isolated large hail and a tornado threat, are expected to develop across parts of the Ohio Valley and Lower Great Lakes this afternoon. Storms with large hail are expected tonight in parts of the central Plains and Ozarks. ...Ohio and Tennessee Valleys/Central Gulf Coast States... A negatively tilted upper-level trough, and an associated surface low, will move into the Great Lakes today. A corridor of maximized surface dewpoints will move eastward across the Ohio Valley today, as a cold front approaches from the west. Scattered thunderstorms will likely develop during the late morning, as low-level convergence and instability increases. These storms, in the form of clusters or short line segments, will move eastward across the Ohio Valley and Lower Great Lakes region during the afternoon. RAP forecast soundings across far eastern Indiana and western Ohio during the early afternoon show a favorable environment for severe storms, with MLCAPE near 1500 J/kg and 0-6 km shear around 50 knots. This should support an isolated large hail threat with the more discrete rotating storms. A wind-damage threat will also be possible, especially with the more organized line segments. Forecast soundings suggest that low-level shear will become more favorable in the late afternoon, with 0-3 km storm-relative helicity increasing into the 225 to 250 m2/s2 range. For this reason, the tornado threat is expected to be greater a bit further east from central and eastern Ohio into far western Pennsylvania. Further south into the Tennessee Valley and central Gulf Coast states, isolated thunderstorms are expected to develop ahead of a cold front, and near a moist axis with surface dewpoints in the 60s F. MLCAPE in the 750 to 1000 J/kg range, along with 0-6 km shear from 40 to 50 knots will be sufficient for an isolated severe threat. Marginally severe wind gusts and hail will be the primary threats. ...Central Plains/Ozarks... An upper-level trough will move through the north-central U.S. tonight, as a 70 to 80 knot mid-level jet passes through the trough. In response, a 40 to 50 knot low-level jet will develop further south across the central Plains. Thunderstorms are expected to initiate near the northern edge of the low-level jet late this evening from central Kansas into far southeast Nebraska. These storms are expected to move eastward across northeast Kansas and into western Missouri. Forecast soundings in northeast Kansas around 06Z have MUCAPE near 2500 J/kg, with effective shear around 45 knots. This, combined with 700-500 mb lapse rates around 7.5 C/km, should be favorable for elevated rotating storms with potential for very large hail. The large hail threat is expected to be greatest in the 04Z to 07Z time window, but may persist through late in the period. ..Broyles/Lyons.. 04/17/2024 Read more

SPC Apr 17, 2024 0600 UTC Day 1 Convective Outlook

1 year 3 months ago
SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1256 AM CDT Wed Apr 17 2024 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE OHIO VALLEY AND LOWER GREAT LAKES...AND IN PARTS OF NORTHEAST KANSAS AND WESTERN MISSOURI... ...SUMMARY... Scattered thunderstorms, capable of wind damage, isolated large hail and a tornado threat, are expected to develop across parts of the Ohio Valley and Lower Great Lakes this afternoon. Storms with large hail are expected tonight in parts of the central Plains and Ozarks. ...Ohio and Tennessee Valleys/Central Gulf Coast States... A negatively tilted upper-level trough, and an associated surface low, will move into the Great Lakes today. A corridor of maximized surface dewpoints will move eastward across the Ohio Valley today, as a cold front approaches from the west. Scattered thunderstorms will likely develop during the late morning, as low-level convergence and instability increases. These storms, in the form of clusters or short line segments, will move eastward across the Ohio Valley and Lower Great Lakes region during the afternoon. RAP forecast soundings across far eastern Indiana and western Ohio during the early afternoon show a favorable environment for severe storms, with MLCAPE near 1500 J/kg and 0-6 km shear around 50 knots. This should support an isolated large hail threat with the more discrete rotating storms. A wind-damage threat will also be possible, especially with the more organized line segments. Forecast soundings suggest that low-level shear will become more favorable in the late afternoon, with 0-3 km storm-relative helicity increasing into the 225 to 250 m2/s2 range. For this reason, the tornado threat is expected to be greater a bit further east from central and eastern Ohio into far western Pennsylvania. Further south into the Tennessee Valley and central Gulf Coast states, isolated thunderstorms are expected to develop ahead of a cold front, and near a moist axis with surface dewpoints in the 60s F. MLCAPE in the 750 to 1000 J/kg range, along with 0-6 km shear from 40 to 50 knots will be sufficient for an isolated severe threat. Marginally severe wind gusts and hail will be the primary threats. ...Central Plains/Ozarks... An upper-level trough will move through the north-central U.S. tonight, as a 70 to 80 knot mid-level jet passes through the trough. In response, a 40 to 50 knot low-level jet will develop further south across the central Plains. Thunderstorms are expected to initiate near the northern edge of the low-level jet late this evening from central Kansas into far southeast Nebraska. These storms are expected to move eastward across northeast Kansas and into western Missouri. Forecast soundings in northeast Kansas around 06Z have MUCAPE near 2500 J/kg, with effective shear around 45 knots. This, combined with 700-500 mb lapse rates around 7.5 C/km, should be favorable for elevated rotating storms with potential for very large hail. The large hail threat is expected to be greatest in the 04Z to 07Z time window, but may persist through late in the period. ..Broyles/Lyons.. 04/17/2024 Read more

SPC Apr 17, 2024 0600 UTC Day 1 Convective Outlook

1 year 3 months ago
SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1256 AM CDT Wed Apr 17 2024 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE OHIO VALLEY AND LOWER GREAT LAKES...AND IN PARTS OF NORTHEAST KANSAS AND WESTERN MISSOURI... ...SUMMARY... Scattered thunderstorms, capable of wind damage, isolated large hail and a tornado threat, are expected to develop across parts of the Ohio Valley and Lower Great Lakes this afternoon. Storms with large hail are expected tonight in parts of the central Plains and Ozarks. ...Ohio and Tennessee Valleys/Central Gulf Coast States... A negatively tilted upper-level trough, and an associated surface low, will move into the Great Lakes today. A corridor of maximized surface dewpoints will move eastward across the Ohio Valley today, as a cold front approaches from the west. Scattered thunderstorms will likely develop during the late morning, as low-level convergence and instability increases. These storms, in the form of clusters or short line segments, will move eastward across the Ohio Valley and Lower Great Lakes region during the afternoon. RAP forecast soundings across far eastern Indiana and western Ohio during the early afternoon show a favorable environment for severe storms, with MLCAPE near 1500 J/kg and 0-6 km shear around 50 knots. This should support an isolated large hail threat with the more discrete rotating storms. A wind-damage threat will also be possible, especially with the more organized line segments. Forecast soundings suggest that low-level shear will become more favorable in the late afternoon, with 0-3 km storm-relative helicity increasing into the 225 to 250 m2/s2 range. For this reason, the tornado threat is expected to be greater a bit further east from central and eastern Ohio into far western Pennsylvania. Further south into the Tennessee Valley and central Gulf Coast states, isolated thunderstorms are expected to develop ahead of a cold front, and near a moist axis with surface dewpoints in the 60s F. MLCAPE in the 750 to 1000 J/kg range, along with 0-6 km shear from 40 to 50 knots will be sufficient for an isolated severe threat. Marginally severe wind gusts and hail will be the primary threats. ...Central Plains/Ozarks... An upper-level trough will move through the north-central U.S. tonight, as a 70 to 80 knot mid-level jet passes through the trough. In response, a 40 to 50 knot low-level jet will develop further south across the central Plains. Thunderstorms are expected to initiate near the northern edge of the low-level jet late this evening from central Kansas into far southeast Nebraska. These storms are expected to move eastward across northeast Kansas and into western Missouri. Forecast soundings in northeast Kansas around 06Z have MUCAPE near 2500 J/kg, with effective shear around 45 knots. This, combined with 700-500 mb lapse rates around 7.5 C/km, should be favorable for elevated rotating storms with potential for very large hail. The large hail threat is expected to be greatest in the 04Z to 07Z time window, but may persist through late in the period. ..Broyles/Lyons.. 04/17/2024 Read more