Aggregator

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0346 AM CDT Mon Apr 01 2024 Valid 041200Z - 091200Z ...DISCUSSION... ...Thursday/Day 4 to Saturday/Day 6... An upper-level low will move across the Northeast on Thursday and Friday, and into the western Atlantic on Saturday. During this period at the end of the week, an upper-level ridge is forecast to move through the central U.S. At the surface, a large area of high pressure is forecast to move from the central U.S. to the eastern states. Due to relatively dry and stable air, severe thunderstorms appear unlikely across most of the continental U.S. through Saturday. The greatest chance of thunderstorms would be in the southern and central Plains on Saturday evening, as weak moisture advection occurs in the Great Plains and an upper-level trough approaches from the southwest. ...Sunday/Day 7 and Monday/Day 8... Moisture advection is forecast to take place ahead of an upper-level trough over the southern Plains and Ark-La-Tex on Sunday and Monday. An isolated severe threat could develop each afternoon across the moist sector, which should be in the southern Plains. The models suggest that instability will remain weak across this moist airmass, which would limit severe threat coverage in most areas. Predictability concerning the spacing of any potential threat remains low at this time, mainly due to the extended range. Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0220 AM CDT Mon Apr 01 2024 Valid 031200Z - 041200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MID-ATLANTIC...CAROLINAS AND CENTRAL FLORIDA PENINSULA... ...SUMMARY... Marginally severe thunderstorms will be possible on Wednesday across parts of the Mid-Atlantic, Carolinas and Florida Peninsula. ...Mid-Atlantic/Carolinas... An upper-level low is forecast to move eastward into the Ohio Valley on Wednesday, as a mid-level jet translates eastward toward the Atlantic Seaboard. At the surface, a cold front is forecast to advance quickly eastward across the Atlantic Seaboard during the morning and afternoon. Surface dewpoints ahead of the front are forecast to be in the mid 60s F, which will contribute to weak destabilization during the day. As surface temperatures warm ahead of the boundary, scattered thunderstorm development is expected during the late morning and early afternoon. The greatest convective coverage should be the Mid-Atlantic, where the exit region of the mid-level jet will likely be associated with a pocket of strong large-scale ascent. This, combined with strong deep-layer shear, could be enough for an isolated wind-damage threat, as low-level lapse rates steepen during the day. Any severe threat is expected to diminish from west to east as the cold front moves into the coastal areas during the afternoon. ...Florida Peninsula... A 90 to 110 knot mid-level jet is forecast to move to the southern Atlantic Seaboard by midday, as a cold front advances southward across the Florida Peninsula. Thunderstorm development will be likely near and ahead of the front across much of the central Florida Peninsula during the afternoon. A moist airmass will be in place ahead of the front across central Florida, where surface dewpoints are forecast to be in the upper 60s and lower 70S F. This should aid weak destabilization. In addition, forecast soundings ahead of the front around 21Z have 0-6 km shear near 50 knots, with 0-3 km lapse rates near 6.5 C/km. This could support an isolated wind-damage threat with short multicell line segments that develop ahead of the front. Hail could also occur with the stronger cells. ..Broyles.. 04/01/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0220 AM CDT Mon Apr 01 2024 Valid 031200Z - 041200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MID-ATLANTIC...CAROLINAS AND CENTRAL FLORIDA PENINSULA... ...SUMMARY... Marginally severe thunderstorms will be possible on Wednesday across parts of the Mid-Atlantic, Carolinas and Florida Peninsula. ...Mid-Atlantic/Carolinas... An upper-level low is forecast to move eastward into the Ohio Valley on Wednesday, as a mid-level jet translates eastward toward the Atlantic Seaboard. At the surface, a cold front is forecast to advance quickly eastward across the Atlantic Seaboard during the morning and afternoon. Surface dewpoints ahead of the front are forecast to be in the mid 60s F, which will contribute to weak destabilization during the day. As surface temperatures warm ahead of the boundary, scattered thunderstorm development is expected during the late morning and early afternoon. The greatest convective coverage should be the Mid-Atlantic, where the exit region of the mid-level jet will likely be associated with a pocket of strong large-scale ascent. This, combined with strong deep-layer shear, could be enough for an isolated wind-damage threat, as low-level lapse rates steepen during the day. Any severe threat is expected to diminish from west to east as the cold front moves into the coastal areas during the afternoon. ...Florida Peninsula... A 90 to 110 knot mid-level jet is forecast to move to the southern Atlantic Seaboard by midday, as a cold front advances southward across the Florida Peninsula. Thunderstorm development will be likely near and ahead of the front across much of the central Florida Peninsula during the afternoon. A moist airmass will be in place ahead of the front across central Florida, where surface dewpoints are forecast to be in the upper 60s and lower 70S F. This should aid weak destabilization. In addition, forecast soundings ahead of the front around 21Z have 0-6 km shear near 50 knots, with 0-3 km lapse rates near 6.5 C/km. This could support an isolated wind-damage threat with short multicell line segments that develop ahead of the front. Hail could also occur with the stronger cells. ..Broyles.. 04/01/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0220 AM CDT Mon Apr 01 2024 Valid 031200Z - 041200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MID-ATLANTIC...CAROLINAS AND CENTRAL FLORIDA PENINSULA... ...SUMMARY... Marginally severe thunderstorms will be possible on Wednesday across parts of the Mid-Atlantic, Carolinas and Florida Peninsula. ...Mid-Atlantic/Carolinas... An upper-level low is forecast to move eastward into the Ohio Valley on Wednesday, as a mid-level jet translates eastward toward the Atlantic Seaboard. At the surface, a cold front is forecast to advance quickly eastward across the Atlantic Seaboard during the morning and afternoon. Surface dewpoints ahead of the front are forecast to be in the mid 60s F, which will contribute to weak destabilization during the day. As surface temperatures warm ahead of the boundary, scattered thunderstorm development is expected during the late morning and early afternoon. The greatest convective coverage should be the Mid-Atlantic, where the exit region of the mid-level jet will likely be associated with a pocket of strong large-scale ascent. This, combined with strong deep-layer shear, could be enough for an isolated wind-damage threat, as low-level lapse rates steepen during the day. Any severe threat is expected to diminish from west to east as the cold front moves into the coastal areas during the afternoon. ...Florida Peninsula... A 90 to 110 knot mid-level jet is forecast to move to the southern Atlantic Seaboard by midday, as a cold front advances southward across the Florida Peninsula. Thunderstorm development will be likely near and ahead of the front across much of the central Florida Peninsula during the afternoon. A moist airmass will be in place ahead of the front across central Florida, where surface dewpoints are forecast to be in the upper 60s and lower 70S F. This should aid weak destabilization. In addition, forecast soundings ahead of the front around 21Z have 0-6 km shear near 50 knots, with 0-3 km lapse rates near 6.5 C/km. This could support an isolated wind-damage threat with short multicell line segments that develop ahead of the front. Hail could also occur with the stronger cells. ..Broyles.. 04/01/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0220 AM CDT Mon Apr 01 2024 Valid 031200Z - 041200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MID-ATLANTIC...CAROLINAS AND CENTRAL FLORIDA PENINSULA... ...SUMMARY... Marginally severe thunderstorms will be possible on Wednesday across parts of the Mid-Atlantic, Carolinas and Florida Peninsula. ...Mid-Atlantic/Carolinas... An upper-level low is forecast to move eastward into the Ohio Valley on Wednesday, as a mid-level jet translates eastward toward the Atlantic Seaboard. At the surface, a cold front is forecast to advance quickly eastward across the Atlantic Seaboard during the morning and afternoon. Surface dewpoints ahead of the front are forecast to be in the mid 60s F, which will contribute to weak destabilization during the day. As surface temperatures warm ahead of the boundary, scattered thunderstorm development is expected during the late morning and early afternoon. The greatest convective coverage should be the Mid-Atlantic, where the exit region of the mid-level jet will likely be associated with a pocket of strong large-scale ascent. This, combined with strong deep-layer shear, could be enough for an isolated wind-damage threat, as low-level lapse rates steepen during the day. Any severe threat is expected to diminish from west to east as the cold front moves into the coastal areas during the afternoon. ...Florida Peninsula... A 90 to 110 knot mid-level jet is forecast to move to the southern Atlantic Seaboard by midday, as a cold front advances southward across the Florida Peninsula. Thunderstorm development will be likely near and ahead of the front across much of the central Florida Peninsula during the afternoon. A moist airmass will be in place ahead of the front across central Florida, where surface dewpoints are forecast to be in the upper 60s and lower 70S F. This should aid weak destabilization. In addition, forecast soundings ahead of the front around 21Z have 0-6 km shear near 50 knots, with 0-3 km lapse rates near 6.5 C/km. This could support an isolated wind-damage threat with short multicell line segments that develop ahead of the front. Hail could also occur with the stronger cells. ..Broyles.. 04/01/2024 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0202 AM CDT Mon Apr 01 2024 Valid 011200Z - 021200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHEAST NEW MEXICO INTO SOUTHWEST TEXAS... ...Synopsis... A very strong mid-level jet will overspread the southern Plains today. Given the well-mixed airmass in the region, very strong winds (30+ mph sustained) are expected. The airmass is not expected to be overly dry and in fact, some precipitation is expected across portions of the Texas Panhandle. However, relative humidity of 20 to 25 percent is likely in the Trans Pecos and Permian Basin. This will result in at least some threat for large fires in the region. ..Bentley.. 04/01/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0202 AM CDT Mon Apr 01 2024 Valid 011200Z - 021200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHEAST NEW MEXICO INTO SOUTHWEST TEXAS... ...Synopsis... A very strong mid-level jet will overspread the southern Plains today. Given the well-mixed airmass in the region, very strong winds (30+ mph sustained) are expected. The airmass is not expected to be overly dry and in fact, some precipitation is expected across portions of the Texas Panhandle. However, relative humidity of 20 to 25 percent is likely in the Trans Pecos and Permian Basin. This will result in at least some threat for large fires in the region. ..Bentley.. 04/01/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0202 AM CDT Mon Apr 01 2024 Valid 011200Z - 021200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHEAST NEW MEXICO INTO SOUTHWEST TEXAS... ...Synopsis... A very strong mid-level jet will overspread the southern Plains today. Given the well-mixed airmass in the region, very strong winds (30+ mph sustained) are expected. The airmass is not expected to be overly dry and in fact, some precipitation is expected across portions of the Texas Panhandle. However, relative humidity of 20 to 25 percent is likely in the Trans Pecos and Permian Basin. This will result in at least some threat for large fires in the region. ..Bentley.. 04/01/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0202 AM CDT Mon Apr 01 2024 Valid 011200Z - 021200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHEAST NEW MEXICO INTO SOUTHWEST TEXAS... ...Synopsis... A very strong mid-level jet will overspread the southern Plains today. Given the well-mixed airmass in the region, very strong winds (30+ mph sustained) are expected. The airmass is not expected to be overly dry and in fact, some precipitation is expected across portions of the Texas Panhandle. However, relative humidity of 20 to 25 percent is likely in the Trans Pecos and Permian Basin. This will result in at least some threat for large fires in the region. ..Bentley.. 04/01/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 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