Severe Storms

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1258 AM CDT Mon Apr 01 2024 Valid 021200Z - 031200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE OHIO AND TENNESSEE VALLEYS... ...SUMMARY... A severe threat is expected on Tuesday from the Ohio and Tennessee Valleys eastward into the Mid-Atlantic, and southward into the central Gulf Coast states. Wind damage and isolated large hail will be possible across a broad area. The tornado threat is expected to be greatest from middle Tennessee north-northeastward into central and northern Kentucky. ...Ohio and Tennessee Valleys/Central Gulf Coast States/Central Appalachians... An upper-level trough is forecast to move eastward into the mid to upper Mississippi Valley on Tuesday, as a cold front advances eastward toward the Ohio and Tennessee Valleys. By afternoon, a north-to-south corridor of maximized low-level moisture is forecast to be in place from the northern Gulf Coast States to central Kentucky, where surface dewpoints are expected to be in the mid 60s F. As instability increases along this corridor, numerous thunderstorms will likely develop, with a linear MCS organizing and moving eastward across the Ohio and Tennessee Valleys during the afternoon and evening. This large MCS should reach the central Appalachians by early to mid evening. A 90 to 100 knot mid-level jet will likely move northeastward into the Ohio Valley during the afternoon. This jet will create strong deep-layer shear across most of the region. Forecast soundings by 21Z from middle Tennessee to central Kentucky have 0-6 km shear in the 70 to 80 knot range. The wind shear and strong large-scale ascent, associated with the mid-level jet, will be favorable for the development of a squall line Tuesday afternoon. This linear MCS will likely have numerous embedded severe storms with the greatest threat being wind damage. The wind-damage threat is expected to maximize during the late afternoon and early evening. QLCS tornadic circulations will be possible along some parts of the line, especially near bowing segments. An isolated large hail threat is also expected in areas where the squall line interacts with locally stronger instability, and with isolated rotating cells that develop ahead of the line. The severe threat is expected to decrease during the mid to late evening as the line moves through the central Appalachians. ...Central Gulf Coast States... An upper-level trough will move eastward across the southern Plains on Tuesday, as a cold front moves eastward into the lower Mississippi Valley. Surface dewpoints should be in the mid to upper 60s F ahead of the front, where some models suggest that MLCAPE will peak in the 1000 to 1200 J/kg range during the afternoon. Scattered thunderstorm development appears likely to take place ahead of the front early in the day, with an organized line segment or cluster moving eastward across the central Gulf Coast States during the afternoon. Strong deep-layer shear will be in place, and low-level lapse rates will steepen during the late morning and early afternoon. The environment will likely support a wind-damage and isolated large-hail threat. An isolated tornado threat will also be possible, especially in the northern Gulf Coast states near the southern edge of the low-level jet. Large-scale ascent and deep-layer shear are forecast to be somewhat weaker across the central and southern Gulf Coast states, which should result in a more isolated severe threat with southward extent. ...Mid-Atlantic... An anticyclonic flow pattern is forecast across the Eastern Seaboard on Tuesday. At the surface, a relatively cold airmass is forecast across much of the Mid-Atlantic due to cold air damming. Above the cold surface air, elevated instability is forecast to increase during the evening, as the exit region of the mid-level jet moves through the central Appalachians. Thunderstorms that form in the unstable air aloft, may have a potential for marginally severe hail during the evening into the early overnight period. ..Broyles.. 04/01/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1258 AM CDT Mon Apr 01 2024 Valid 021200Z - 031200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE OHIO AND TENNESSEE VALLEYS... ...SUMMARY... A severe threat is expected on Tuesday from the Ohio and Tennessee Valleys eastward into the Mid-Atlantic, and southward into the central Gulf Coast states. Wind damage and isolated large hail will be possible across a broad area. The tornado threat is expected to be greatest from middle Tennessee north-northeastward into central and northern Kentucky. ...Ohio and Tennessee Valleys/Central Gulf Coast States/Central Appalachians... An upper-level trough is forecast to move eastward into the mid to upper Mississippi Valley on Tuesday, as a cold front advances eastward toward the Ohio and Tennessee Valleys. By afternoon, a north-to-south corridor of maximized low-level moisture is forecast to be in place from the northern Gulf Coast States to central Kentucky, where surface dewpoints are expected to be in the mid 60s F. As instability increases along this corridor, numerous thunderstorms will likely develop, with a linear MCS organizing and moving eastward across the Ohio and Tennessee Valleys during the afternoon and evening. This large MCS should reach the central Appalachians by early to mid evening. A 90 to 100 knot mid-level jet will likely move northeastward into the Ohio Valley during the afternoon. This jet will create strong deep-layer shear across most of the region. Forecast soundings by 21Z from middle Tennessee to central Kentucky have 0-6 km shear in the 70 to 80 knot range. The wind shear and strong large-scale ascent, associated with the mid-level jet, will be favorable for the development of a squall line Tuesday afternoon. This linear MCS will likely have numerous embedded severe storms with the greatest threat being wind damage. The wind-damage threat is expected to maximize during the late afternoon and early evening. QLCS tornadic circulations will be possible along some parts of the line, especially near bowing segments. An isolated large hail threat is also expected in areas where the squall line interacts with locally stronger instability, and with isolated rotating cells that develop ahead of the line. The severe threat is expected to decrease during the mid to late evening as the line moves through the central Appalachians. ...Central Gulf Coast States... An upper-level trough will move eastward across the southern Plains on Tuesday, as a cold front moves eastward into the lower Mississippi Valley. Surface dewpoints should be in the mid to upper 60s F ahead of the front, where some models suggest that MLCAPE will peak in the 1000 to 1200 J/kg range during the afternoon. Scattered thunderstorm development appears likely to take place ahead of the front early in the day, with an organized line segment or cluster moving eastward across the central Gulf Coast States during the afternoon. Strong deep-layer shear will be in place, and low-level lapse rates will steepen during the late morning and early afternoon. The environment will likely support a wind-damage and isolated large-hail threat. An isolated tornado threat will also be possible, especially in the northern Gulf Coast states near the southern edge of the low-level jet. Large-scale ascent and deep-layer shear are forecast to be somewhat weaker across the central and southern Gulf Coast states, which should result in a more isolated severe threat with southward extent. ...Mid-Atlantic... An anticyclonic flow pattern is forecast across the Eastern Seaboard on Tuesday. At the surface, a relatively cold airmass is forecast across much of the Mid-Atlantic due to cold air damming. Above the cold surface air, elevated instability is forecast to increase during the evening, as the exit region of the mid-level jet moves through the central Appalachians. Thunderstorms that form in the unstable air aloft, may have a potential for marginally severe hail during the evening into the early overnight period. ..Broyles.. 04/01/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1258 AM CDT Mon Apr 01 2024 Valid 021200Z - 031200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE OHIO AND TENNESSEE VALLEYS... ...SUMMARY... A severe threat is expected on Tuesday from the Ohio and Tennessee Valleys eastward into the Mid-Atlantic, and southward into the central Gulf Coast states. Wind damage and isolated large hail will be possible across a broad area. The tornado threat is expected to be greatest from middle Tennessee north-northeastward into central and northern Kentucky. ...Ohio and Tennessee Valleys/Central Gulf Coast States/Central Appalachians... An upper-level trough is forecast to move eastward into the mid to upper Mississippi Valley on Tuesday, as a cold front advances eastward toward the Ohio and Tennessee Valleys. By afternoon, a north-to-south corridor of maximized low-level moisture is forecast to be in place from the northern Gulf Coast States to central Kentucky, where surface dewpoints are expected to be in the mid 60s F. As instability increases along this corridor, numerous thunderstorms will likely develop, with a linear MCS organizing and moving eastward across the Ohio and Tennessee Valleys during the afternoon and evening. This large MCS should reach the central Appalachians by early to mid evening. A 90 to 100 knot mid-level jet will likely move northeastward into the Ohio Valley during the afternoon. This jet will create strong deep-layer shear across most of the region. Forecast soundings by 21Z from middle Tennessee to central Kentucky have 0-6 km shear in the 70 to 80 knot range. The wind shear and strong large-scale ascent, associated with the mid-level jet, will be favorable for the development of a squall line Tuesday afternoon. This linear MCS will likely have numerous embedded severe storms with the greatest threat being wind damage. The wind-damage threat is expected to maximize during the late afternoon and early evening. QLCS tornadic circulations will be possible along some parts of the line, especially near bowing segments. An isolated large hail threat is also expected in areas where the squall line interacts with locally stronger instability, and with isolated rotating cells that develop ahead of the line. The severe threat is expected to decrease during the mid to late evening as the line moves through the central Appalachians. ...Central Gulf Coast States... An upper-level trough will move eastward across the southern Plains on Tuesday, as a cold front moves eastward into the lower Mississippi Valley. Surface dewpoints should be in the mid to upper 60s F ahead of the front, where some models suggest that MLCAPE will peak in the 1000 to 1200 J/kg range during the afternoon. Scattered thunderstorm development appears likely to take place ahead of the front early in the day, with an organized line segment or cluster moving eastward across the central Gulf Coast States during the afternoon. Strong deep-layer shear will be in place, and low-level lapse rates will steepen during the late morning and early afternoon. The environment will likely support a wind-damage and isolated large-hail threat. An isolated tornado threat will also be possible, especially in the northern Gulf Coast states near the southern edge of the low-level jet. Large-scale ascent and deep-layer shear are forecast to be somewhat weaker across the central and southern Gulf Coast states, which should result in a more isolated severe threat with southward extent. ...Mid-Atlantic... An anticyclonic flow pattern is forecast across the Eastern Seaboard on Tuesday. At the surface, a relatively cold airmass is forecast across much of the Mid-Atlantic due to cold air damming. Above the cold surface air, elevated instability is forecast to increase during the evening, as the exit region of the mid-level jet moves through the central Appalachians. Thunderstorms that form in the unstable air aloft, may have a potential for marginally severe hail during the evening into the early overnight period. ..Broyles.. 04/01/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1258 AM CDT Mon Apr 01 2024 Valid 021200Z - 031200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE OHIO AND TENNESSEE VALLEYS... ...SUMMARY... A severe threat is expected on Tuesday from the Ohio and Tennessee Valleys eastward into the Mid-Atlantic, and southward into the central Gulf Coast states. Wind damage and isolated large hail will be possible across a broad area. The tornado threat is expected to be greatest from middle Tennessee north-northeastward into central and northern Kentucky. ...Ohio and Tennessee Valleys/Central Gulf Coast States/Central Appalachians... An upper-level trough is forecast to move eastward into the mid to upper Mississippi Valley on Tuesday, as a cold front advances eastward toward the Ohio and Tennessee Valleys. By afternoon, a north-to-south corridor of maximized low-level moisture is forecast to be in place from the northern Gulf Coast States to central Kentucky, where surface dewpoints are expected to be in the mid 60s F. As instability increases along this corridor, numerous thunderstorms will likely develop, with a linear MCS organizing and moving eastward across the Ohio and Tennessee Valleys during the afternoon and evening. This large MCS should reach the central Appalachians by early to mid evening. A 90 to 100 knot mid-level jet will likely move northeastward into the Ohio Valley during the afternoon. This jet will create strong deep-layer shear across most of the region. Forecast soundings by 21Z from middle Tennessee to central Kentucky have 0-6 km shear in the 70 to 80 knot range. The wind shear and strong large-scale ascent, associated with the mid-level jet, will be favorable for the development of a squall line Tuesday afternoon. This linear MCS will likely have numerous embedded severe storms with the greatest threat being wind damage. The wind-damage threat is expected to maximize during the late afternoon and early evening. QLCS tornadic circulations will be possible along some parts of the line, especially near bowing segments. An isolated large hail threat is also expected in areas where the squall line interacts with locally stronger instability, and with isolated rotating cells that develop ahead of the line. The severe threat is expected to decrease during the mid to late evening as the line moves through the central Appalachians. ...Central Gulf Coast States... An upper-level trough will move eastward across the southern Plains on Tuesday, as a cold front moves eastward into the lower Mississippi Valley. Surface dewpoints should be in the mid to upper 60s F ahead of the front, where some models suggest that MLCAPE will peak in the 1000 to 1200 J/kg range during the afternoon. Scattered thunderstorm development appears likely to take place ahead of the front early in the day, with an organized line segment or cluster moving eastward across the central Gulf Coast States during the afternoon. Strong deep-layer shear will be in place, and low-level lapse rates will steepen during the late morning and early afternoon. The environment will likely support a wind-damage and isolated large-hail threat. An isolated tornado threat will also be possible, especially in the northern Gulf Coast states near the southern edge of the low-level jet. Large-scale ascent and deep-layer shear are forecast to be somewhat weaker across the central and southern Gulf Coast states, which should result in a more isolated severe threat with southward extent. ...Mid-Atlantic... An anticyclonic flow pattern is forecast across the Eastern Seaboard on Tuesday. At the surface, a relatively cold airmass is forecast across much of the Mid-Atlantic due to cold air damming. Above the cold surface air, elevated instability is forecast to increase during the evening, as the exit region of the mid-level jet moves through the central Appalachians. Thunderstorms that form in the unstable air aloft, may have a potential for marginally severe hail during the evening into the early overnight period. ..Broyles.. 04/01/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0106 AM CDT Mon Apr 01 2024 Valid 011200Z - 021200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM THE SOUTHERN PLAINS TO THE OZARKS AND INTO FAR WESTERN INDIANA.... ...SUMMARY... Severe weather is expected to occur over a broad region from the southern Plains, the Ozarks, portions of the Ohio Valley, and into a small part of the Mid-Atlantic. Large to very large hail, damaging winds, and tornadoes (some strong) are possible. The severe threat will peak this afternoon/evening in the southern Plains with the greatest threat for the Ohio Valley vicinity being the evening/overnight period. ...Synopsis... A large, positively tilted upper-level trough will shift east from the Southwest to the central Plains today. A mid-level shortwave trough, currently rounding the base of the large scale trough, will advance quickly northeast through the day today within a strong mid-level jet. This strong flow will overspread a broad, very moist warm sector and lead to severe weather across a large portion of the Southern Plains into the Midwest. A surface low is present across eastern Colorado this morning with a stationary front extending eastward across Kansas and Missouri and into the Ohio Valley. This surface low will drift slowly east through the day and the front is expected to lift north across Missouri as a warm front during the afternoon. ...North Texas, central and eastern Oklahoma, southeast Kansas, and the Ozarks... Mid 60s dewpoints are expected across much of the warm sector east of the dryline by mid-day today with temperatures warming into the 70s to low 80s. Moderate to strong instability is expected to develop by the time ascent associated with the approaching trough overspreads the dryline. Once this occurs, expect rapid storm development along the dryline from southern Kansas to north Texas. Very strong shear, and mostly straight hodographs will support splitting supercells initially capable of large to potentially giant hail across a broad region from southwest Missouri to north Texas. Storm evolution off the dryline is still somewhat uncertain. Some guidance depicts more discrete development off the dryline and the potential for multiple rounds of supercells, while other CAM guidance waits until closer to 00Z to convect and leads to upscale growth and significant storm interaction within the first few hours. This evolution will have a significant impact on the longevity of the giant hail threat, but even with a messy storm mode, very large hail will remain a threat. Low-level shear is expected to be very weak for much of the day, which will limit the tornado threat. However, by the evening, the low-level jet is expected to strengthen with the ejecting wave and low-level shear will improve. The most favorable hodographs are expected across northeast Oklahoma into southeast Kansas and southwest/central Missouri in a region where mature supercells will likely be ongoing. Therefore, a more favorable period for tornadoes and potentially strong tornadoes may exist from 23-03Z as the low-level shear improves. ...Eastern Missouri into southern Illinois... At least isolated supercells are expected to develop along the warm front from northern Missouri into central Illinois this afternoon and evening. Strong instability and very strong shear will support large to very large hail. In addition, storm motion is expected to be parallel to the surface front. Therefore, any supercells which can latch onto the warm front will have a higher tornado threat. However, more isolated storm coverage and uncertainty regarding storm evolution preclude higher tornado probabilities in this region. Later in the evening and into the overnight hours, storms from the west will move into the region with a threat for large hail, a few tornadoes, and severe wind gusts. ...Ohio River Vicinity... Supercells from Illinois may continue east along the warm front into the evening across southern Indiana and potentially southern Ohio. Additional storms may also develop along this frontal zone with a primary threat of large hail. Weaker instability/shear should limit the overall threat from these storms compared to farther west. However, moderate instability and strong shear will support a threat for large hail, damaging wind gusts, and perhaps a tornado. Overnight, a cluster of storms is expected to approach from the west. The overnight environment will continue to support a severe threat with 1500 J/kg MLCAPE and effective shear in excess of 50 knots. There is still considerable uncertainty how this cluster will evolve. A cluster of supercells would pose a threat for all severe weather hazards, while a more organized MCS may support a greater severe wind and QLCS tornado threat. ...Central Texas... Strong instability is expected to develop ahead of a dryline across central Texas this afternoon. Confluence along the dryline and weak height falls should provide ample support for isolated to scattered storm development. Any storms which develop will be capable of very large to giant hail, given very strong instability and shear an expected supercellular storm mode. ..Bentley/Darrow.. 04/01/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0106 AM CDT Mon Apr 01 2024 Valid 011200Z - 021200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM THE SOUTHERN PLAINS TO THE OZARKS AND INTO FAR WESTERN INDIANA.... ...SUMMARY... Severe weather is expected to occur over a broad region from the southern Plains, the Ozarks, portions of the Ohio Valley, and into a small part of the Mid-Atlantic. Large to very large hail, damaging winds, and tornadoes (some strong) are possible. The severe threat will peak this afternoon/evening in the southern Plains with the greatest threat for the Ohio Valley vicinity being the evening/overnight period. ...Synopsis... A large, positively tilted upper-level trough will shift east from the Southwest to the central Plains today. A mid-level shortwave trough, currently rounding the base of the large scale trough, will advance quickly northeast through the day today within a strong mid-level jet. This strong flow will overspread a broad, very moist warm sector and lead to severe weather across a large portion of the Southern Plains into the Midwest. A surface low is present across eastern Colorado this morning with a stationary front extending eastward across Kansas and Missouri and into the Ohio Valley. This surface low will drift slowly east through the day and the front is expected to lift north across Missouri as a warm front during the afternoon. ...North Texas, central and eastern Oklahoma, southeast Kansas, and the Ozarks... Mid 60s dewpoints are expected across much of the warm sector east of the dryline by mid-day today with temperatures warming into the 70s to low 80s. Moderate to strong instability is expected to develop by the time ascent associated with the approaching trough overspreads the dryline. Once this occurs, expect rapid storm development along the dryline from southern Kansas to north Texas. Very strong shear, and mostly straight hodographs will support splitting supercells initially capable of large to potentially giant hail across a broad region from southwest Missouri to north Texas. Storm evolution off the dryline is still somewhat uncertain. Some guidance depicts more discrete development off the dryline and the potential for multiple rounds of supercells, while other CAM guidance waits until closer to 00Z to convect and leads to upscale growth and significant storm interaction within the first few hours. This evolution will have a significant impact on the longevity of the giant hail threat, but even with a messy storm mode, very large hail will remain a threat. Low-level shear is expected to be very weak for much of the day, which will limit the tornado threat. However, by the evening, the low-level jet is expected to strengthen with the ejecting wave and low-level shear will improve. The most favorable hodographs are expected across northeast Oklahoma into southeast Kansas and southwest/central Missouri in a region where mature supercells will likely be ongoing. Therefore, a more favorable period for tornadoes and potentially strong tornadoes may exist from 23-03Z as the low-level shear improves. ...Eastern Missouri into southern Illinois... At least isolated supercells are expected to develop along the warm front from northern Missouri into central Illinois this afternoon and evening. Strong instability and very strong shear will support large to very large hail. In addition, storm motion is expected to be parallel to the surface front. Therefore, any supercells which can latch onto the warm front will have a higher tornado threat. However, more isolated storm coverage and uncertainty regarding storm evolution preclude higher tornado probabilities in this region. Later in the evening and into the overnight hours, storms from the west will move into the region with a threat for large hail, a few tornadoes, and severe wind gusts. ...Ohio River Vicinity... Supercells from Illinois may continue east along the warm front into the evening across southern Indiana and potentially southern Ohio. Additional storms may also develop along this frontal zone with a primary threat of large hail. Weaker instability/shear should limit the overall threat from these storms compared to farther west. However, moderate instability and strong shear will support a threat for large hail, damaging wind gusts, and perhaps a tornado. Overnight, a cluster of storms is expected to approach from the west. The overnight environment will continue to support a severe threat with 1500 J/kg MLCAPE and effective shear in excess of 50 knots. There is still considerable uncertainty how this cluster will evolve. A cluster of supercells would pose a threat for all severe weather hazards, while a more organized MCS may support a greater severe wind and QLCS tornado threat. ...Central Texas... Strong instability is expected to develop ahead of a dryline across central Texas this afternoon. Confluence along the dryline and weak height falls should provide ample support for isolated to scattered storm development. Any storms which develop will be capable of very large to giant hail, given very strong instability and shear an expected supercellular storm mode. ..Bentley/Darrow.. 04/01/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0106 AM CDT Mon Apr 01 2024 Valid 011200Z - 021200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM THE SOUTHERN PLAINS TO THE OZARKS AND INTO FAR WESTERN INDIANA.... ...SUMMARY... Severe weather is expected to occur over a broad region from the southern Plains, the Ozarks, portions of the Ohio Valley, and into a small part of the Mid-Atlantic. Large to very large hail, damaging winds, and tornadoes (some strong) are possible. The severe threat will peak this afternoon/evening in the southern Plains with the greatest threat for the Ohio Valley vicinity being the evening/overnight period. ...Synopsis... A large, positively tilted upper-level trough will shift east from the Southwest to the central Plains today. A mid-level shortwave trough, currently rounding the base of the large scale trough, will advance quickly northeast through the day today within a strong mid-level jet. This strong flow will overspread a broad, very moist warm sector and lead to severe weather across a large portion of the Southern Plains into the Midwest. A surface low is present across eastern Colorado this morning with a stationary front extending eastward across Kansas and Missouri and into the Ohio Valley. This surface low will drift slowly east through the day and the front is expected to lift north across Missouri as a warm front during the afternoon. ...North Texas, central and eastern Oklahoma, southeast Kansas, and the Ozarks... Mid 60s dewpoints are expected across much of the warm sector east of the dryline by mid-day today with temperatures warming into the 70s to low 80s. Moderate to strong instability is expected to develop by the time ascent associated with the approaching trough overspreads the dryline. Once this occurs, expect rapid storm development along the dryline from southern Kansas to north Texas. Very strong shear, and mostly straight hodographs will support splitting supercells initially capable of large to potentially giant hail across a broad region from southwest Missouri to north Texas. Storm evolution off the dryline is still somewhat uncertain. Some guidance depicts more discrete development off the dryline and the potential for multiple rounds of supercells, while other CAM guidance waits until closer to 00Z to convect and leads to upscale growth and significant storm interaction within the first few hours. This evolution will have a significant impact on the longevity of the giant hail threat, but even with a messy storm mode, very large hail will remain a threat. Low-level shear is expected to be very weak for much of the day, which will limit the tornado threat. However, by the evening, the low-level jet is expected to strengthen with the ejecting wave and low-level shear will improve. The most favorable hodographs are expected across northeast Oklahoma into southeast Kansas and southwest/central Missouri in a region where mature supercells will likely be ongoing. Therefore, a more favorable period for tornadoes and potentially strong tornadoes may exist from 23-03Z as the low-level shear improves. ...Eastern Missouri into southern Illinois... At least isolated supercells are expected to develop along the warm front from northern Missouri into central Illinois this afternoon and evening. Strong instability and very strong shear will support large to very large hail. In addition, storm motion is expected to be parallel to the surface front. Therefore, any supercells which can latch onto the warm front will have a higher tornado threat. However, more isolated storm coverage and uncertainty regarding storm evolution preclude higher tornado probabilities in this region. Later in the evening and into the overnight hours, storms from the west will move into the region with a threat for large hail, a few tornadoes, and severe wind gusts. ...Ohio River Vicinity... Supercells from Illinois may continue east along the warm front into the evening across southern Indiana and potentially southern Ohio. Additional storms may also develop along this frontal zone with a primary threat of large hail. Weaker instability/shear should limit the overall threat from these storms compared to farther west. However, moderate instability and strong shear will support a threat for large hail, damaging wind gusts, and perhaps a tornado. Overnight, a cluster of storms is expected to approach from the west. The overnight environment will continue to support a severe threat with 1500 J/kg MLCAPE and effective shear in excess of 50 knots. There is still considerable uncertainty how this cluster will evolve. A cluster of supercells would pose a threat for all severe weather hazards, while a more organized MCS may support a greater severe wind and QLCS tornado threat. ...Central Texas... Strong instability is expected to develop ahead of a dryline across central Texas this afternoon. Confluence along the dryline and weak height falls should provide ample support for isolated to scattered storm development. Any storms which develop will be capable of very large to giant hail, given very strong instability and shear an expected supercellular storm mode. ..Bentley/Darrow.. 04/01/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0106 AM CDT Mon Apr 01 2024 Valid 011200Z - 021200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM THE SOUTHERN PLAINS TO THE OZARKS AND INTO FAR WESTERN INDIANA.... ...SUMMARY... Severe weather is expected to occur over a broad region from the southern Plains, the Ozarks, portions of the Ohio Valley, and into a small part of the Mid-Atlantic. Large to very large hail, damaging winds, and tornadoes (some strong) are possible. The severe threat will peak this afternoon/evening in the southern Plains with the greatest threat for the Ohio Valley vicinity being the evening/overnight period. ...Synopsis... A large, positively tilted upper-level trough will shift east from the Southwest to the central Plains today. A mid-level shortwave trough, currently rounding the base of the large scale trough, will advance quickly northeast through the day today within a strong mid-level jet. This strong flow will overspread a broad, very moist warm sector and lead to severe weather across a large portion of the Southern Plains into the Midwest. A surface low is present across eastern Colorado this morning with a stationary front extending eastward across Kansas and Missouri and into the Ohio Valley. This surface low will drift slowly east through the day and the front is expected to lift north across Missouri as a warm front during the afternoon. ...North Texas, central and eastern Oklahoma, southeast Kansas, and the Ozarks... Mid 60s dewpoints are expected across much of the warm sector east of the dryline by mid-day today with temperatures warming into the 70s to low 80s. Moderate to strong instability is expected to develop by the time ascent associated with the approaching trough overspreads the dryline. Once this occurs, expect rapid storm development along the dryline from southern Kansas to north Texas. Very strong shear, and mostly straight hodographs will support splitting supercells initially capable of large to potentially giant hail across a broad region from southwest Missouri to north Texas. Storm evolution off the dryline is still somewhat uncertain. Some guidance depicts more discrete development off the dryline and the potential for multiple rounds of supercells, while other CAM guidance waits until closer to 00Z to convect and leads to upscale growth and significant storm interaction within the first few hours. This evolution will have a significant impact on the longevity of the giant hail threat, but even with a messy storm mode, very large hail will remain a threat. Low-level shear is expected to be very weak for much of the day, which will limit the tornado threat. However, by the evening, the low-level jet is expected to strengthen with the ejecting wave and low-level shear will improve. The most favorable hodographs are expected across northeast Oklahoma into southeast Kansas and southwest/central Missouri in a region where mature supercells will likely be ongoing. Therefore, a more favorable period for tornadoes and potentially strong tornadoes may exist from 23-03Z as the low-level shear improves. ...Eastern Missouri into southern Illinois... At least isolated supercells are expected to develop along the warm front from northern Missouri into central Illinois this afternoon and evening. Strong instability and very strong shear will support large to very large hail. In addition, storm motion is expected to be parallel to the surface front. Therefore, any supercells which can latch onto the warm front will have a higher tornado threat. However, more isolated storm coverage and uncertainty regarding storm evolution preclude higher tornado probabilities in this region. Later in the evening and into the overnight hours, storms from the west will move into the region with a threat for large hail, a few tornadoes, and severe wind gusts. ...Ohio River Vicinity... Supercells from Illinois may continue east along the warm front into the evening across southern Indiana and potentially southern Ohio. Additional storms may also develop along this frontal zone with a primary threat of large hail. Weaker instability/shear should limit the overall threat from these storms compared to farther west. However, moderate instability and strong shear will support a threat for large hail, damaging wind gusts, and perhaps a tornado. Overnight, a cluster of storms is expected to approach from the west. The overnight environment will continue to support a severe threat with 1500 J/kg MLCAPE and effective shear in excess of 50 knots. There is still considerable uncertainty how this cluster will evolve. A cluster of supercells would pose a threat for all severe weather hazards, while a more organized MCS may support a greater severe wind and QLCS tornado threat. ...Central Texas... Strong instability is expected to develop ahead of a dryline across central Texas this afternoon. Confluence along the dryline and weak height falls should provide ample support for isolated to scattered storm development. Any storms which develop will be capable of very large to giant hail, given very strong instability and shear an expected supercellular storm mode. ..Bentley/Darrow.. 04/01/2024 Read more

MD 0318 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PORTIONS OF CENTRAL ILLINOIS INTO WESTERN INDIANA
Mesoscale Discussion 0318 NWS Storm Prediction Center Norman OK 0738 PM CDT Sun Mar 31 2024 Areas affected...portions of central Illinois into western Indiana Concerning...Severe potential...Watch unlikely Valid 010038Z - 010245Z Probability of Watch Issuance...20 percent SUMMARY...A long-lived supercell may persist for at least a few more hours across central and eastern IL into western IN with severe hail. The severe weather threat is expected to remain localized through evening. DISCUSSION...A long-lived supercell continues to traverse a diffuse warm-front over central IL, where upper 60s/mid 50s F surface temperatures/dewpoints are boosting MLCAPE/MUCAPE to 500 J/kg (per 00Z mesoanalysis). Though CAPE profiles are thin (based on the latest RAP forecast soundings and the 00Z observed ILX sounding), modestly curved low-level hodographs with mid/upper-level elongation suggest that vertical wind shear remains strong (i.e. 60+ kts of effective bulk shear). While the supercell will likely remain outflow dominant, efficient severe hail production should continue for at least a few more hours across central IL into western IN before the low-level jet veers, reducing convergence along the front and potentially supporting weakening convective potential later this evening. In the meantime, the severe threat may be constrained to this lone supercell. Convective trends will continue to be monitored for the need of a WW issuance, but current thinking is that the severe threat should remain localized over central IL/IN this evening. ..Squitieri/Guyer.. 04/01/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...IND...ILX... LAT...LON 39588894 39878942 40138937 40228902 40108806 39808662 39678615 39308599 38978631 39018688 39268815 39588894 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0743 PM CDT Sun Mar 31 2024 Valid 010100Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN ILLINOIS ACROSS CENTRAL AND SOUTHEASTERN INDIANA.... ...SUMMARY... A few storms may produce large hail into the overnight period across portions of the Ohio Valley. ...Eastern IL/southern IN Tonight... A long track supercell across central Illinois will continue to move east-southeast along the frontal boundary through this evening. A similar mesoscale environment to what was observed on the 00Z ILX RAOB is expected to persist along the front which could maintain this supercell for several more hours. However, 850mb flow is expected to gradually veer through the evening which may eventually lead to weakening of this supercell. Have maintained a narrow Slight risk ahead of this storm with a primary threat of large hail. Please see MCD 318 for additional discussion of this storm. Elsewhere, a few strong to perhaps severe storms are possible in the vicinity of the same warm front, but height rises and the aforementioned veering low-level jet will likely limit coverage and intensity of storms. ..Bentley.. 04/01/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0743 PM CDT Sun Mar 31 2024 Valid 010100Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN ILLINOIS ACROSS CENTRAL AND SOUTHEASTERN INDIANA.... ...SUMMARY... A few storms may produce large hail into the overnight period across portions of the Ohio Valley. ...Eastern IL/southern IN Tonight... A long track supercell across central Illinois will continue to move east-southeast along the frontal boundary through this evening. A similar mesoscale environment to what was observed on the 00Z ILX RAOB is expected to persist along the front which could maintain this supercell for several more hours. However, 850mb flow is expected to gradually veer through the evening which may eventually lead to weakening of this supercell. Have maintained a narrow Slight risk ahead of this storm with a primary threat of large hail. Please see MCD 318 for additional discussion of this storm. Elsewhere, a few strong to perhaps severe storms are possible in the vicinity of the same warm front, but height rises and the aforementioned veering low-level jet will likely limit coverage and intensity of storms. ..Bentley.. 04/01/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0743 PM CDT Sun Mar 31 2024 Valid 010100Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN ILLINOIS ACROSS CENTRAL AND SOUTHEASTERN INDIANA.... ...SUMMARY... A few storms may produce large hail into the overnight period across portions of the Ohio Valley. ...Eastern IL/southern IN Tonight... A long track supercell across central Illinois will continue to move east-southeast along the frontal boundary through this evening. A similar mesoscale environment to what was observed on the 00Z ILX RAOB is expected to persist along the front which could maintain this supercell for several more hours. However, 850mb flow is expected to gradually veer through the evening which may eventually lead to weakening of this supercell. Have maintained a narrow Slight risk ahead of this storm with a primary threat of large hail. Please see MCD 318 for additional discussion of this storm. Elsewhere, a few strong to perhaps severe storms are possible in the vicinity of the same warm front, but height rises and the aforementioned veering low-level jet will likely limit coverage and intensity of storms. ..Bentley.. 04/01/2024 Read more

No watches are valid as of Sun Mar 31 23:46:01 UTC 2024.

MD 0317 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR PORTIONS OF NORTHERN MISSOURI INTO CENTRAL ILLINOIS
Mesoscale Discussion 0317 NWS Storm Prediction Center Norman OK 0526 PM CDT Sun Mar 31 2024 Areas affected...portions of northern Missouri into central Illinois Concerning...Severe potential...Watch possible Valid 312226Z - 010030Z Probability of Watch Issuance...40 percent SUMMARY...Severe hail will accompany ongoing elevated supercell in west-central IL, moving into central IL, in the near term. Convective initiation is more uncertain farther south along the warm front in northern MO given weak forcing. Buoyancy and shear does favor severe storm development should convective initiation occur. Convective trends are being monitored for the need of a WW issuance. DISCUSSION...An elevated supercell in west-central IL, with a history of marginally severe hail, persists within strong zonal mid-level flow to the north of a warm front. Strong 850-700 mb WAA continues to advect adequate moisture ahead of the supercell in central IL, boosting MUCAPE into the 500-1000 J/kg range (per 21Z mesoanalysis). Meanwhile the stronger southwesterly WAA beneath 60+ kt westerly 500 mb flow is contributing to modestly curved but elongated hodographs. As such, severe hail development may persist with this supercell for a couple more hours. Meanwhile, surface-based convective initiation from agitated CU farther south along the warm front, draped from roughly Linn County MO to Jasper County IL, remains uncertain in the absence of strong forcing. Surface heating has boosted MLCAPE into the 1000-1500 J/kg range amid stronger deep-layer shear (i.e. elongated and curved hodographs supporting 60+ kts of effective bulk shear). As such, any storms that can initiate and become sustained may produce severe hail/wind. Convective trends will continue to be monitored for the possibility of convective initiation over the next few hours. ..Squitieri/Guyer.. 03/31/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LOT...ILX...LSX...DVN...EAX... LAT...LON 39919320 40399240 40689096 40678934 40358816 39788775 39208768 38848780 38788853 39149028 39539183 39669268 39919320 Read more

MD 0316 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PORTIONS OF CENTRAL VIRGINIA
Mesoscale Discussion 0316 NWS Storm Prediction Center Norman OK 0443 PM CDT Sun Mar 31 2024 Areas affected...portions of central Virginia Concerning...Severe potential...Watch unlikely Valid 312143Z - 312345Z Probability of Watch Issuance...5 percent SUMMARY...A couple instances of hail and perhaps strong wind gusts will accompany the stronger storms over the next few hours. The severe threat is expected to remain isolated into the evening hours. DISCUSSION...Multiple discrete storms (possibly small supercells) have been percolating in intensity over the past hour or so, as seen by MRMS mosaic radar data. These storms are traversing a diffuse effective warm front, where at least upper 50s F surface dewpoints and steep low-level lapse rates are contributing up to 500 J/kg of thin MLCAPE. RAP forecast soundings and regional VADs show relatively straight, elongated hodographs, which favor a continued discrete storm mode with persistent enough mid-level rotation to foster some hail production. A couple of strong wind gusts are also possible given the steep low-level lapse rates. The severe threat should remain sparse and localized into the evening hours, when a weakening trend is expected given nocturnal cooling. ..Squitieri/Guyer.. 03/31/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...AKQ...LWX...RNK... LAT...LON 38107956 37637809 37127725 36817705 36587724 36647775 37117863 37547944 37837970 38107956 Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0500 PM CDT Sun Mar 31 2024 Valid 021200Z - 081200Z On Day 3/Tuesday, a positively tilted mid/upper-level trough will move east-southeastward over the central/southern Plains, while a separate northern-stream jet streak digs southward across the northern/central Plains and MS Valley. This will promote breezy/gusty northerly post-frontal surface winds across much of the Great Plains. While generally cool surface temperatures will limit RH reductions for most areas, locally elevated fire-weather conditions are still possible where fuels are dry. Over the Rio Grande in south TX, these breezy winds will overlap downslope-aided lower RH, favoring locally elevated fire-weather conditions. However, confidence in the development of critical conditions is too low for probabilities. Thereafter, the strong post-frontal winds will overspread the MS, OH, and TN Valleys on Day 4/Wednesday, before shifting eastward into the Southeast/Mid-Atlantic on Day 5/Thursday. Preceding rainfall and somewhat marginal RH reductions should generally temper fire-weather concerns, though elevated conditions cannot be ruled out for areas that miss out on substantial rainfall. For Days 6-7/Friday-Saturday, medium-range guidance and ensembles are in very good agreement, depicting high-amplitude large-scale troughs over the East and West -- characteristic of an omega block pattern. Strong meridional flow ahead of the western CONUS trough and antecedent drying will promote strong surface winds and low RH across the central/southern High Plains both days. Given the above-average predictability pattern, 70-percent Critical probabilities have been added for each day. A gap in the 70-percent probabilities was added for Day 6/Friday to account for preceding rainfall over northeast NM and far southeast CO, though these areas may need to be connected if fuels can dry out sufficiently. ..Weinman.. 03/31/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0500 PM CDT Sun Mar 31 2024 Valid 021200Z - 081200Z On Day 3/Tuesday, a positively tilted mid/upper-level trough will move east-southeastward over the central/southern Plains, while a separate northern-stream jet streak digs southward across the northern/central Plains and MS Valley. This will promote breezy/gusty northerly post-frontal surface winds across much of the Great Plains. While generally cool surface temperatures will limit RH reductions for most areas, locally elevated fire-weather conditions are still possible where fuels are dry. Over the Rio Grande in south TX, these breezy winds will overlap downslope-aided lower RH, favoring locally elevated fire-weather conditions. However, confidence in the development of critical conditions is too low for probabilities. Thereafter, the strong post-frontal winds will overspread the MS, OH, and TN Valleys on Day 4/Wednesday, before shifting eastward into the Southeast/Mid-Atlantic on Day 5/Thursday. Preceding rainfall and somewhat marginal RH reductions should generally temper fire-weather concerns, though elevated conditions cannot be ruled out for areas that miss out on substantial rainfall. For Days 6-7/Friday-Saturday, medium-range guidance and ensembles are in very good agreement, depicting high-amplitude large-scale troughs over the East and West -- characteristic of an omega block pattern. Strong meridional flow ahead of the western CONUS trough and antecedent drying will promote strong surface winds and low RH across the central/southern High Plains both days. Given the above-average predictability pattern, 70-percent Critical probabilities have been added for each day. A gap in the 70-percent probabilities was added for Day 6/Friday to account for preceding rainfall over northeast NM and far southeast CO, though these areas may need to be connected if fuels can dry out sufficiently. ..Weinman.. 03/31/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0500 PM CDT Sun Mar 31 2024 Valid 021200Z - 081200Z On Day 3/Tuesday, a positively tilted mid/upper-level trough will move east-southeastward over the central/southern Plains, while a separate northern-stream jet streak digs southward across the northern/central Plains and MS Valley. This will promote breezy/gusty northerly post-frontal surface winds across much of the Great Plains. While generally cool surface temperatures will limit RH reductions for most areas, locally elevated fire-weather conditions are still possible where fuels are dry. Over the Rio Grande in south TX, these breezy winds will overlap downslope-aided lower RH, favoring locally elevated fire-weather conditions. However, confidence in the development of critical conditions is too low for probabilities. Thereafter, the strong post-frontal winds will overspread the MS, OH, and TN Valleys on Day 4/Wednesday, before shifting eastward into the Southeast/Mid-Atlantic on Day 5/Thursday. Preceding rainfall and somewhat marginal RH reductions should generally temper fire-weather concerns, though elevated conditions cannot be ruled out for areas that miss out on substantial rainfall. For Days 6-7/Friday-Saturday, medium-range guidance and ensembles are in very good agreement, depicting high-amplitude large-scale troughs over the East and West -- characteristic of an omega block pattern. Strong meridional flow ahead of the western CONUS trough and antecedent drying will promote strong surface winds and low RH across the central/southern High Plains both days. Given the above-average predictability pattern, 70-percent Critical probabilities have been added for each day. A gap in the 70-percent probabilities was added for Day 6/Friday to account for preceding rainfall over northeast NM and far southeast CO, though these areas may need to be connected if fuels can dry out sufficiently. ..Weinman.. 03/31/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0500 PM CDT Sun Mar 31 2024 Valid 021200Z - 081200Z On Day 3/Tuesday, a positively tilted mid/upper-level trough will move east-southeastward over the central/southern Plains, while a separate northern-stream jet streak digs southward across the northern/central Plains and MS Valley. This will promote breezy/gusty northerly post-frontal surface winds across much of the Great Plains. While generally cool surface temperatures will limit RH reductions for most areas, locally elevated fire-weather conditions are still possible where fuels are dry. Over the Rio Grande in south TX, these breezy winds will overlap downslope-aided lower RH, favoring locally elevated fire-weather conditions. However, confidence in the development of critical conditions is too low for probabilities. Thereafter, the strong post-frontal winds will overspread the MS, OH, and TN Valleys on Day 4/Wednesday, before shifting eastward into the Southeast/Mid-Atlantic on Day 5/Thursday. Preceding rainfall and somewhat marginal RH reductions should generally temper fire-weather concerns, though elevated conditions cannot be ruled out for areas that miss out on substantial rainfall. For Days 6-7/Friday-Saturday, medium-range guidance and ensembles are in very good agreement, depicting high-amplitude large-scale troughs over the East and West -- characteristic of an omega block pattern. Strong meridional flow ahead of the western CONUS trough and antecedent drying will promote strong surface winds and low RH across the central/southern High Plains both days. Given the above-average predictability pattern, 70-percent Critical probabilities have been added for each day. A gap in the 70-percent probabilities was added for Day 6/Friday to account for preceding rainfall over northeast NM and far southeast CO, though these areas may need to be connected if fuels can dry out sufficiently. ..Weinman.. 03/31/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0500 PM CDT Sun Mar 31 2024 Valid 021200Z - 081200Z On Day 3/Tuesday, a positively tilted mid/upper-level trough will move east-southeastward over the central/southern Plains, while a separate northern-stream jet streak digs southward across the northern/central Plains and MS Valley. This will promote breezy/gusty northerly post-frontal surface winds across much of the Great Plains. While generally cool surface temperatures will limit RH reductions for most areas, locally elevated fire-weather conditions are still possible where fuels are dry. Over the Rio Grande in south TX, these breezy winds will overlap downslope-aided lower RH, favoring locally elevated fire-weather conditions. However, confidence in the development of critical conditions is too low for probabilities. Thereafter, the strong post-frontal winds will overspread the MS, OH, and TN Valleys on Day 4/Wednesday, before shifting eastward into the Southeast/Mid-Atlantic on Day 5/Thursday. Preceding rainfall and somewhat marginal RH reductions should generally temper fire-weather concerns, though elevated conditions cannot be ruled out for areas that miss out on substantial rainfall. For Days 6-7/Friday-Saturday, medium-range guidance and ensembles are in very good agreement, depicting high-amplitude large-scale troughs over the East and West -- characteristic of an omega block pattern. Strong meridional flow ahead of the western CONUS trough and antecedent drying will promote strong surface winds and low RH across the central/southern High Plains both days. Given the above-average predictability pattern, 70-percent Critical probabilities have been added for each day. A gap in the 70-percent probabilities was added for Day 6/Friday to account for preceding rainfall over northeast NM and far southeast CO, though these areas may need to be connected if fuels can dry out sufficiently. ..Weinman.. 03/31/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more