Severe Storms

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1159 PM CDT Fri May 24 2024 Valid 261200Z - 271200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS SUNDAY AFTERNOON INTO SUNDAY EVENING ACROSS MUCH OF EASTERN MISSOURI...CENTRAL AND SOUTHERN ILLINOIS...CENTRAL AND SOUTHERN INDIANA...MUCH OF KENTUCKY AND ADJACENT NORTHERN TENNESSEE... ...SUMMARY... Widespread strong to severe thunderstorm development appears possible across parts of the southeastern Great Plains and lower Missouri Valley into the Ohio and Tennessee Valleys Sunday afternoon through Sunday night. It is possible this could include the evolution of at least one large, long-lived organized cluster of storms posing a risk for damaging wind gusts, from parts of east central Missouri and west central Illinois through much of Kentucky and adjacent portions of northern Tennessee. ...Synopsis... Models indicate that initially low-amplitude mid-level troughing, comprised of at least a couple of smaller-scale perturbations emerging from the Great Basin and Southwest, may undergo substantive amplification while slowly progressing northeast and east of the lower Missouri Valley and central Great Plains during this period. The lead embedded perturbation may be accompanied by notable further deepening of a relatively compact developing cyclone across the lower Missouri Valley through the upper Great Lakes region by late Sunday night. To the southwest of this cyclone, a cold front is forecast to surge southward through much of Missouri, northwestern Arkansas and the southern Great Plains Red River Valley. It appears that the front will be preceded by a sharpening dryline near the Kansas/Missouri border area southwestward through central Texas by late afternoon, while a plume of warm elevated mixed-layer air continues advecting east of the southeastern Great Plains through much of the mid/lower Mississippi Valley and lower Ohio Valley through southern Appalachians. Beneath this regime, moderately strong southwesterly low-level flow will contribute to low-level moisture return across the Mississippi Valley through the lower Great Lakes and Appalachians, but this may be complicated by the influence of remnant convection and convective outflow from areas upstream late Saturday through Saturday night. ...Southeastern Great Plains through Ohio Valley/Great Lakes... Latest model output, including convection allowing guidance, suggests that several remnant convective clusters may be ongoing at 12Z Sunday across parts of the lower Missouri/middle Mississippi Valley vicinity. It is possible that destabilizing moist low-level inflow to the south and southwest of the southern-most activity may be sufficient to maintain or support re-intensification of convection east-southeastward through parts of the lower Ohio/Tennessee Valleys during the day. If this occurs, beneath a seasonably strong west-southwesterly mid/upper jet, vertical shear may contribute to an organizing system capable of producing sustained damaging wind gusts. Otherwise, a perhaps more prominent signal persists in model output that a corridor of strengthening differential surface heating, near the western flank of modifying convective outflow and beneath the leading edge of the plume of warm and capping elevated mixed-layer air, may become a focus for renewed convective develop by Sunday afternoon. Initially in a corridor roughly across northeast/east central Missouri into west central Illinois, lift associated with warm advection and inflow of boundary-layer air characterized by CAPE in excess of 3000 J/kg may contribute to upscale growing convective development, with potential to organize into a southeastward propagating convective system. Given seasonably high boundary-layer moisture content beneath dry mid-levels with very steep lapse rates, a strong cold pool may eventually evolve and pose a risk for sustained damaging wind gusts across parts of the lower Ohio and Tennessee Valleys through Sunday evening. ..Kerr.. 05/25/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1159 PM CDT Fri May 24 2024 Valid 261200Z - 271200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS SUNDAY AFTERNOON INTO SUNDAY EVENING ACROSS MUCH OF EASTERN MISSOURI...CENTRAL AND SOUTHERN ILLINOIS...CENTRAL AND SOUTHERN INDIANA...MUCH OF KENTUCKY AND ADJACENT NORTHERN TENNESSEE... ...SUMMARY... Widespread strong to severe thunderstorm development appears possible across parts of the southeastern Great Plains and lower Missouri Valley into the Ohio and Tennessee Valleys Sunday afternoon through Sunday night. It is possible this could include the evolution of at least one large, long-lived organized cluster of storms posing a risk for damaging wind gusts, from parts of east central Missouri and west central Illinois through much of Kentucky and adjacent portions of northern Tennessee. ...Synopsis... Models indicate that initially low-amplitude mid-level troughing, comprised of at least a couple of smaller-scale perturbations emerging from the Great Basin and Southwest, may undergo substantive amplification while slowly progressing northeast and east of the lower Missouri Valley and central Great Plains during this period. The lead embedded perturbation may be accompanied by notable further deepening of a relatively compact developing cyclone across the lower Missouri Valley through the upper Great Lakes region by late Sunday night. To the southwest of this cyclone, a cold front is forecast to surge southward through much of Missouri, northwestern Arkansas and the southern Great Plains Red River Valley. It appears that the front will be preceded by a sharpening dryline near the Kansas/Missouri border area southwestward through central Texas by late afternoon, while a plume of warm elevated mixed-layer air continues advecting east of the southeastern Great Plains through much of the mid/lower Mississippi Valley and lower Ohio Valley through southern Appalachians. Beneath this regime, moderately strong southwesterly low-level flow will contribute to low-level moisture return across the Mississippi Valley through the lower Great Lakes and Appalachians, but this may be complicated by the influence of remnant convection and convective outflow from areas upstream late Saturday through Saturday night. ...Southeastern Great Plains through Ohio Valley/Great Lakes... Latest model output, including convection allowing guidance, suggests that several remnant convective clusters may be ongoing at 12Z Sunday across parts of the lower Missouri/middle Mississippi Valley vicinity. It is possible that destabilizing moist low-level inflow to the south and southwest of the southern-most activity may be sufficient to maintain or support re-intensification of convection east-southeastward through parts of the lower Ohio/Tennessee Valleys during the day. If this occurs, beneath a seasonably strong west-southwesterly mid/upper jet, vertical shear may contribute to an organizing system capable of producing sustained damaging wind gusts. Otherwise, a perhaps more prominent signal persists in model output that a corridor of strengthening differential surface heating, near the western flank of modifying convective outflow and beneath the leading edge of the plume of warm and capping elevated mixed-layer air, may become a focus for renewed convective develop by Sunday afternoon. Initially in a corridor roughly across northeast/east central Missouri into west central Illinois, lift associated with warm advection and inflow of boundary-layer air characterized by CAPE in excess of 3000 J/kg may contribute to upscale growing convective development, with potential to organize into a southeastward propagating convective system. Given seasonably high boundary-layer moisture content beneath dry mid-levels with very steep lapse rates, a strong cold pool may eventually evolve and pose a risk for sustained damaging wind gusts across parts of the lower Ohio and Tennessee Valleys through Sunday evening. ..Kerr.. 05/25/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1258 AM CDT Sat May 25 2024 Valid 251200Z - 261200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS IN PARTS OF KANSAS/OKLAHOMA AND FAR SOUTHWEST MISSOURI... ...SUMMARY... An outbreak of severe thunderstorms is forecast from late afternoon into tonight across parts of the central and southern Great Plains. A few long-lived supercells capable of intense tornadoes may occur. Giant hail and destructive wind gusts are also expected. ...Central and southern Great Plains... Much uncertainty plagues this outlook cycle, with the level 4-Moderate risk left as-is. This evening's guidance has trended slower and more confined with the boundary-layer moisture return, with most CAMs also suggesting earlier afternoon initiation occurring along the periphery of the richer moisture in west TX. Level 5-High risk potential remains evident with the 00Z HRRR indicating a possible tornado outbreak scenario with long-lived strong to violent tornadoes. Consensus of evening guidance suggests low-level moisture return will be within a confined swath emanating north from the south-central TX portion of the Rio Grande Valley into west TX. This will occur downstream of a modestly amplified mid-level trough, consisting of multiple embedded shortwave impulses, ejecting across the West into the central and southern High Plains. Surface temperatures west of the dryline will become hot, and most CAMs indicate early to mid-afternoon thunderstorm development in the TX Big Country/western north TX vicinity. It is probable that this will become the southern extent of the overall severe threat with slow-moving supercells persisting into the evening. Across OK/KS, richer and deeper boundary-layer moisture ahead of the dryline should be confined to western OK through late afternoon. A more well-mixed boundary layer is expected farther north in western/central KS, while the rich moisture should be shallow in central OK before deepening later. Most guidance suggests high-based thunderstorms will develop in the late afternoon across southwest NE and northwest KS, where mid-level cooling will be greatest. Very large hail and isolated severe wind gusts will be the primary threats during the afternoon with relatively elongated/straight hodographs supporting potential for left and right-splitting supercells. A strengthening low-level jet will aid in the tornado threat substantially increasing by early evening. The most volatile environment for long-lived, intense tornadic supercells should exist over the western half of OK. Primary uncertainty precluding an upgrade is the degree of impact earlier afternoon storms to the south may have on this setup with left-splits/outflows. The northern periphery of the richer/deeper moisture surge and robust low-level jet is eventually expected to reach at least into southern KS during the evening. Supercells in this region will strengthen as this occurs, and become capable of producing long-lived, intense tornadoes after dusk. But with time tonight, increasing large-scale ascent should support a supercell to bow echo to MCS evolution towards the Ozark Plateau vicinity. This should yield a swath of damaging winds, with embedded significant severe gusts and tornadoes possible as it tracks eastward along the MLCAPE gradient overnight. ...Eastern States... Three areas of level 1-MRGL risk are forecast today with sporadic severe hail and locally damaging winds possible. Remnant morning convection and attendant MCVs may aid in isolated severe across parts of the Deep South early, before spreading/developing east towards parts of the coastal Atlantic Southeast during the afternoon. Separately, a marginal supercell wind profile will also exist along the southeast FL sea breeze. Across the Lower Great Lakes to central/northern Appalachians, initial mid-level ridging will evolve to a flatter, zonal flow regime. The trailing surface front attendant to a nearly stationary, occluded cyclone along the southeast MB/northwest ON border area should aid in isolated to scattered thunderstorms this afternoon, some of which should become strong. ..Grams/Moore.. 05/25/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1258 AM CDT Sat May 25 2024 Valid 251200Z - 261200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS IN PARTS OF KANSAS/OKLAHOMA AND FAR SOUTHWEST MISSOURI... ...SUMMARY... An outbreak of severe thunderstorms is forecast from late afternoon into tonight across parts of the central and southern Great Plains. A few long-lived supercells capable of intense tornadoes may occur. Giant hail and destructive wind gusts are also expected. ...Central and southern Great Plains... Much uncertainty plagues this outlook cycle, with the level 4-Moderate risk left as-is. This evening's guidance has trended slower and more confined with the boundary-layer moisture return, with most CAMs also suggesting earlier afternoon initiation occurring along the periphery of the richer moisture in west TX. Level 5-High risk potential remains evident with the 00Z HRRR indicating a possible tornado outbreak scenario with long-lived strong to violent tornadoes. Consensus of evening guidance suggests low-level moisture return will be within a confined swath emanating north from the south-central TX portion of the Rio Grande Valley into west TX. This will occur downstream of a modestly amplified mid-level trough, consisting of multiple embedded shortwave impulses, ejecting across the West into the central and southern High Plains. Surface temperatures west of the dryline will become hot, and most CAMs indicate early to mid-afternoon thunderstorm development in the TX Big Country/western north TX vicinity. It is probable that this will become the southern extent of the overall severe threat with slow-moving supercells persisting into the evening. Across OK/KS, richer and deeper boundary-layer moisture ahead of the dryline should be confined to western OK through late afternoon. A more well-mixed boundary layer is expected farther north in western/central KS, while the rich moisture should be shallow in central OK before deepening later. Most guidance suggests high-based thunderstorms will develop in the late afternoon across southwest NE and northwest KS, where mid-level cooling will be greatest. Very large hail and isolated severe wind gusts will be the primary threats during the afternoon with relatively elongated/straight hodographs supporting potential for left and right-splitting supercells. A strengthening low-level jet will aid in the tornado threat substantially increasing by early evening. The most volatile environment for long-lived, intense tornadic supercells should exist over the western half of OK. Primary uncertainty precluding an upgrade is the degree of impact earlier afternoon storms to the south may have on this setup with left-splits/outflows. The northern periphery of the richer/deeper moisture surge and robust low-level jet is eventually expected to reach at least into southern KS during the evening. Supercells in this region will strengthen as this occurs, and become capable of producing long-lived, intense tornadoes after dusk. But with time tonight, increasing large-scale ascent should support a supercell to bow echo to MCS evolution towards the Ozark Plateau vicinity. This should yield a swath of damaging winds, with embedded significant severe gusts and tornadoes possible as it tracks eastward along the MLCAPE gradient overnight. ...Eastern States... Three areas of level 1-MRGL risk are forecast today with sporadic severe hail and locally damaging winds possible. Remnant morning convection and attendant MCVs may aid in isolated severe across parts of the Deep South early, before spreading/developing east towards parts of the coastal Atlantic Southeast during the afternoon. Separately, a marginal supercell wind profile will also exist along the southeast FL sea breeze. Across the Lower Great Lakes to central/northern Appalachians, initial mid-level ridging will evolve to a flatter, zonal flow regime. The trailing surface front attendant to a nearly stationary, occluded cyclone along the southeast MB/northwest ON border area should aid in isolated to scattered thunderstorms this afternoon, some of which should become strong. ..Grams/Moore.. 05/25/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1258 AM CDT Sat May 25 2024 Valid 251200Z - 261200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS IN PARTS OF KANSAS/OKLAHOMA AND FAR SOUTHWEST MISSOURI... ...SUMMARY... An outbreak of severe thunderstorms is forecast from late afternoon into tonight across parts of the central and southern Great Plains. A few long-lived supercells capable of intense tornadoes may occur. Giant hail and destructive wind gusts are also expected. ...Central and southern Great Plains... Much uncertainty plagues this outlook cycle, with the level 4-Moderate risk left as-is. This evening's guidance has trended slower and more confined with the boundary-layer moisture return, with most CAMs also suggesting earlier afternoon initiation occurring along the periphery of the richer moisture in west TX. Level 5-High risk potential remains evident with the 00Z HRRR indicating a possible tornado outbreak scenario with long-lived strong to violent tornadoes. Consensus of evening guidance suggests low-level moisture return will be within a confined swath emanating north from the south-central TX portion of the Rio Grande Valley into west TX. This will occur downstream of a modestly amplified mid-level trough, consisting of multiple embedded shortwave impulses, ejecting across the West into the central and southern High Plains. Surface temperatures west of the dryline will become hot, and most CAMs indicate early to mid-afternoon thunderstorm development in the TX Big Country/western north TX vicinity. It is probable that this will become the southern extent of the overall severe threat with slow-moving supercells persisting into the evening. Across OK/KS, richer and deeper boundary-layer moisture ahead of the dryline should be confined to western OK through late afternoon. A more well-mixed boundary layer is expected farther north in western/central KS, while the rich moisture should be shallow in central OK before deepening later. Most guidance suggests high-based thunderstorms will develop in the late afternoon across southwest NE and northwest KS, where mid-level cooling will be greatest. Very large hail and isolated severe wind gusts will be the primary threats during the afternoon with relatively elongated/straight hodographs supporting potential for left and right-splitting supercells. A strengthening low-level jet will aid in the tornado threat substantially increasing by early evening. The most volatile environment for long-lived, intense tornadic supercells should exist over the western half of OK. Primary uncertainty precluding an upgrade is the degree of impact earlier afternoon storms to the south may have on this setup with left-splits/outflows. The northern periphery of the richer/deeper moisture surge and robust low-level jet is eventually expected to reach at least into southern KS during the evening. Supercells in this region will strengthen as this occurs, and become capable of producing long-lived, intense tornadoes after dusk. But with time tonight, increasing large-scale ascent should support a supercell to bow echo to MCS evolution towards the Ozark Plateau vicinity. This should yield a swath of damaging winds, with embedded significant severe gusts and tornadoes possible as it tracks eastward along the MLCAPE gradient overnight. ...Eastern States... Three areas of level 1-MRGL risk are forecast today with sporadic severe hail and locally damaging winds possible. Remnant morning convection and attendant MCVs may aid in isolated severe across parts of the Deep South early, before spreading/developing east towards parts of the coastal Atlantic Southeast during the afternoon. Separately, a marginal supercell wind profile will also exist along the southeast FL sea breeze. Across the Lower Great Lakes to central/northern Appalachians, initial mid-level ridging will evolve to a flatter, zonal flow regime. The trailing surface front attendant to a nearly stationary, occluded cyclone along the southeast MB/northwest ON border area should aid in isolated to scattered thunderstorms this afternoon, some of which should become strong. ..Grams/Moore.. 05/25/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1258 AM CDT Sat May 25 2024 Valid 251200Z - 261200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS IN PARTS OF KANSAS/OKLAHOMA AND FAR SOUTHWEST MISSOURI... ...SUMMARY... An outbreak of severe thunderstorms is forecast from late afternoon into tonight across parts of the central and southern Great Plains. A few long-lived supercells capable of intense tornadoes may occur. Giant hail and destructive wind gusts are also expected. ...Central and southern Great Plains... Much uncertainty plagues this outlook cycle, with the level 4-Moderate risk left as-is. This evening's guidance has trended slower and more confined with the boundary-layer moisture return, with most CAMs also suggesting earlier afternoon initiation occurring along the periphery of the richer moisture in west TX. Level 5-High risk potential remains evident with the 00Z HRRR indicating a possible tornado outbreak scenario with long-lived strong to violent tornadoes. Consensus of evening guidance suggests low-level moisture return will be within a confined swath emanating north from the south-central TX portion of the Rio Grande Valley into west TX. This will occur downstream of a modestly amplified mid-level trough, consisting of multiple embedded shortwave impulses, ejecting across the West into the central and southern High Plains. Surface temperatures west of the dryline will become hot, and most CAMs indicate early to mid-afternoon thunderstorm development in the TX Big Country/western north TX vicinity. It is probable that this will become the southern extent of the overall severe threat with slow-moving supercells persisting into the evening. Across OK/KS, richer and deeper boundary-layer moisture ahead of the dryline should be confined to western OK through late afternoon. A more well-mixed boundary layer is expected farther north in western/central KS, while the rich moisture should be shallow in central OK before deepening later. Most guidance suggests high-based thunderstorms will develop in the late afternoon across southwest NE and northwest KS, where mid-level cooling will be greatest. Very large hail and isolated severe wind gusts will be the primary threats during the afternoon with relatively elongated/straight hodographs supporting potential for left and right-splitting supercells. A strengthening low-level jet will aid in the tornado threat substantially increasing by early evening. The most volatile environment for long-lived, intense tornadic supercells should exist over the western half of OK. Primary uncertainty precluding an upgrade is the degree of impact earlier afternoon storms to the south may have on this setup with left-splits/outflows. The northern periphery of the richer/deeper moisture surge and robust low-level jet is eventually expected to reach at least into southern KS during the evening. Supercells in this region will strengthen as this occurs, and become capable of producing long-lived, intense tornadoes after dusk. But with time tonight, increasing large-scale ascent should support a supercell to bow echo to MCS evolution towards the Ozark Plateau vicinity. This should yield a swath of damaging winds, with embedded significant severe gusts and tornadoes possible as it tracks eastward along the MLCAPE gradient overnight. ...Eastern States... Three areas of level 1-MRGL risk are forecast today with sporadic severe hail and locally damaging winds possible. Remnant morning convection and attendant MCVs may aid in isolated severe across parts of the Deep South early, before spreading/developing east towards parts of the coastal Atlantic Southeast during the afternoon. Separately, a marginal supercell wind profile will also exist along the southeast FL sea breeze. Across the Lower Great Lakes to central/northern Appalachians, initial mid-level ridging will evolve to a flatter, zonal flow regime. The trailing surface front attendant to a nearly stationary, occluded cyclone along the southeast MB/northwest ON border area should aid in isolated to scattered thunderstorms this afternoon, some of which should become strong. ..Grams/Moore.. 05/25/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1258 AM CDT Sat May 25 2024 Valid 251200Z - 261200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS IN PARTS OF KANSAS/OKLAHOMA AND FAR SOUTHWEST MISSOURI... ...SUMMARY... An outbreak of severe thunderstorms is forecast from late afternoon into tonight across parts of the central and southern Great Plains. A few long-lived supercells capable of intense tornadoes may occur. Giant hail and destructive wind gusts are also expected. ...Central and southern Great Plains... Much uncertainty plagues this outlook cycle, with the level 4-Moderate risk left as-is. This evening's guidance has trended slower and more confined with the boundary-layer moisture return, with most CAMs also suggesting earlier afternoon initiation occurring along the periphery of the richer moisture in west TX. Level 5-High risk potential remains evident with the 00Z HRRR indicating a possible tornado outbreak scenario with long-lived strong to violent tornadoes. Consensus of evening guidance suggests low-level moisture return will be within a confined swath emanating north from the south-central TX portion of the Rio Grande Valley into west TX. This will occur downstream of a modestly amplified mid-level trough, consisting of multiple embedded shortwave impulses, ejecting across the West into the central and southern High Plains. Surface temperatures west of the dryline will become hot, and most CAMs indicate early to mid-afternoon thunderstorm development in the TX Big Country/western north TX vicinity. It is probable that this will become the southern extent of the overall severe threat with slow-moving supercells persisting into the evening. Across OK/KS, richer and deeper boundary-layer moisture ahead of the dryline should be confined to western OK through late afternoon. A more well-mixed boundary layer is expected farther north in western/central KS, while the rich moisture should be shallow in central OK before deepening later. Most guidance suggests high-based thunderstorms will develop in the late afternoon across southwest NE and northwest KS, where mid-level cooling will be greatest. Very large hail and isolated severe wind gusts will be the primary threats during the afternoon with relatively elongated/straight hodographs supporting potential for left and right-splitting supercells. A strengthening low-level jet will aid in the tornado threat substantially increasing by early evening. The most volatile environment for long-lived, intense tornadic supercells should exist over the western half of OK. Primary uncertainty precluding an upgrade is the degree of impact earlier afternoon storms to the south may have on this setup with left-splits/outflows. The northern periphery of the richer/deeper moisture surge and robust low-level jet is eventually expected to reach at least into southern KS during the evening. Supercells in this region will strengthen as this occurs, and become capable of producing long-lived, intense tornadoes after dusk. But with time tonight, increasing large-scale ascent should support a supercell to bow echo to MCS evolution towards the Ozark Plateau vicinity. This should yield a swath of damaging winds, with embedded significant severe gusts and tornadoes possible as it tracks eastward along the MLCAPE gradient overnight. ...Eastern States... Three areas of level 1-MRGL risk are forecast today with sporadic severe hail and locally damaging winds possible. Remnant morning convection and attendant MCVs may aid in isolated severe across parts of the Deep South early, before spreading/developing east towards parts of the coastal Atlantic Southeast during the afternoon. Separately, a marginal supercell wind profile will also exist along the southeast FL sea breeze. Across the Lower Great Lakes to central/northern Appalachians, initial mid-level ridging will evolve to a flatter, zonal flow regime. The trailing surface front attendant to a nearly stationary, occluded cyclone along the southeast MB/northwest ON border area should aid in isolated to scattered thunderstorms this afternoon, some of which should become strong. ..Grams/Moore.. 05/25/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1258 AM CDT Sat May 25 2024 Valid 251200Z - 261200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS IN PARTS OF KANSAS/OKLAHOMA AND FAR SOUTHWEST MISSOURI... ...SUMMARY... An outbreak of severe thunderstorms is forecast from late afternoon into tonight across parts of the central and southern Great Plains. A few long-lived supercells capable of intense tornadoes may occur. Giant hail and destructive wind gusts are also expected. ...Central and southern Great Plains... Much uncertainty plagues this outlook cycle, with the level 4-Moderate risk left as-is. This evening's guidance has trended slower and more confined with the boundary-layer moisture return, with most CAMs also suggesting earlier afternoon initiation occurring along the periphery of the richer moisture in west TX. Level 5-High risk potential remains evident with the 00Z HRRR indicating a possible tornado outbreak scenario with long-lived strong to violent tornadoes. Consensus of evening guidance suggests low-level moisture return will be within a confined swath emanating north from the south-central TX portion of the Rio Grande Valley into west TX. This will occur downstream of a modestly amplified mid-level trough, consisting of multiple embedded shortwave impulses, ejecting across the West into the central and southern High Plains. Surface temperatures west of the dryline will become hot, and most CAMs indicate early to mid-afternoon thunderstorm development in the TX Big Country/western north TX vicinity. It is probable that this will become the southern extent of the overall severe threat with slow-moving supercells persisting into the evening. Across OK/KS, richer and deeper boundary-layer moisture ahead of the dryline should be confined to western OK through late afternoon. A more well-mixed boundary layer is expected farther north in western/central KS, while the rich moisture should be shallow in central OK before deepening later. Most guidance suggests high-based thunderstorms will develop in the late afternoon across southwest NE and northwest KS, where mid-level cooling will be greatest. Very large hail and isolated severe wind gusts will be the primary threats during the afternoon with relatively elongated/straight hodographs supporting potential for left and right-splitting supercells. A strengthening low-level jet will aid in the tornado threat substantially increasing by early evening. The most volatile environment for long-lived, intense tornadic supercells should exist over the western half of OK. Primary uncertainty precluding an upgrade is the degree of impact earlier afternoon storms to the south may have on this setup with left-splits/outflows. The northern periphery of the richer/deeper moisture surge and robust low-level jet is eventually expected to reach at least into southern KS during the evening. Supercells in this region will strengthen as this occurs, and become capable of producing long-lived, intense tornadoes after dusk. But with time tonight, increasing large-scale ascent should support a supercell to bow echo to MCS evolution towards the Ozark Plateau vicinity. This should yield a swath of damaging winds, with embedded significant severe gusts and tornadoes possible as it tracks eastward along the MLCAPE gradient overnight. ...Eastern States... Three areas of level 1-MRGL risk are forecast today with sporadic severe hail and locally damaging winds possible. Remnant morning convection and attendant MCVs may aid in isolated severe across parts of the Deep South early, before spreading/developing east towards parts of the coastal Atlantic Southeast during the afternoon. Separately, a marginal supercell wind profile will also exist along the southeast FL sea breeze. Across the Lower Great Lakes to central/northern Appalachians, initial mid-level ridging will evolve to a flatter, zonal flow regime. The trailing surface front attendant to a nearly stationary, occluded cyclone along the southeast MB/northwest ON border area should aid in isolated to scattered thunderstorms this afternoon, some of which should become strong. ..Grams/Moore.. 05/25/2024 Read more

MD 0946 CONCERNING SEVERE THUNDERSTORM WATCH 304... FOR SOUTHERN MISSOURI AND FAR NORTHWEST ARKANSAS
Mesoscale Discussion 0946 NWS Storm Prediction Center Norman OK 0946 PM CDT Fri May 24 2024 Areas affected...Southern Missouri and far northwest Arkansas Concerning...Severe Thunderstorm Watch 304... Valid 250246Z - 250445Z The severe weather threat for Severe Thunderstorm Watch 304 continues. SUMMARY...Isolated thunderstorms will continue along a cold front across south-central Missouri and along the MO/AR border for the next 1-2 hours. These storms may periodically intensify to severe limits and pose a large hail/damaging wind threat. DISCUSSION...Isolated thunderstorms continue to develop along a cold front as it migrates into south-central MO. Although the observed 00 UTC SGF sounding sampled an very supportive environment for severe convection (MLCAPE nearly 3000 J/kg with a 0-6 km BWD value of 45 knots), convection has largely struggled to maintain intensity, likely owing to a combination of diminishing forcing for ascent along the front and the onset of nocturnal stabilization. However, a few stronger updraft pulses have been noted over the past 30 minutes and have intensified to severe limits based on MRMS vertical ice and MESH estimates. Given weak ascent within an otherwise favorable environment, the expectation through 04 UTC is for continued development of weak convection with occasional stronger updraft pulses that may intensify to severe limits. Unless a more robust cell can develop some degree of mid-level rotation and/or a sufficiently intense cold pool, storm longevity should be limited. Consequently, the severe hail/wind threat should remain somewhat isolated as storms move into south-central MO and along the MO/AR border. ..Moore.. 05/25/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LZK...SGF...TSA... LAT...LON 36289441 37009320 37179266 37139211 37099164 36879156 36719163 36559191 36359258 36169321 36089356 36099395 36149419 36289441 Read more

MD 0945 CONCERNING SEVERE THUNDERSTORM WATCH 303...305... FOR FAR EASTERN OKLAHOMA...ARKANSAS...FAR NORTHWEST LOUISIANA...NORTHEAST TEXAS
Mesoscale Discussion 0945 NWS Storm Prediction Center Norman OK 0902 PM CDT Fri May 24 2024 Areas affected...Far Eastern Oklahoma...Arkansas...Far Northwest Louisiana...Northeast Texas Concerning...Severe Thunderstorm Watch 303...305... Valid 250202Z - 250400Z The severe weather threat for Severe Thunderstorm Watch 303, 305 continues. SUMMARY...The severe threat across the Ark-La-Tex is expected to continue for several more hours. Large hail and wind damage will be the primary threats, although the strongest of cells could also have an isolated tornado threat. DISCUSSION...Latest mosaic radar imagery shows a large MCS, with scattered severe storms, located from northeast Texas extending northward into eastern Oklahoma and northeastward into southwest Arkansas. The airmass across much of the Ark-La-Tex is strongly unstable with the RAP estimating MLCAPE generally in the 3000 to 4000 J/kg range. In addition, forecast soundings this evening across much of the unstable airmass have moderate deep-layer shear, with 700-500 mb lapse rates in the 7 to 7.5 C/km range. The environment will continue to support supercells with large hail and wind damage. A wind-damage threat will also be likely with the more intense short line segments. The severe threat is expected to continue into the late evening, but should become more widely scattered as instability begins to decrease across the region. ..Broyles.. 05/25/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...MEG...JAN...LZK...SHV...TSA...FWD... LAT...LON 32689284 33359151 33809103 34209091 34699138 34969203 35409304 35679373 35689430 35229465 34759474 34009469 33499495 32749621 32279666 31859659 31629632 31679559 32179414 32689284 Read more

MD 0944 CONCERNING SEVERE THUNDERSTORM WATCH 302... FOR EASTERN MISSOURI AND FAR WESTERN ILLINOIS
Mesoscale Discussion 0944 NWS Storm Prediction Center Norman OK 0849 PM CDT Fri May 24 2024 Areas affected...Eastern Missouri and far western Illinois Concerning...Severe Thunderstorm Watch 302... Valid 250149Z - 250315Z The severe weather threat for Severe Thunderstorm Watch 302 continues. SUMMARY...A severe hail/wind threat may persist for another hour or two across eastern Missouri and far western Illinois as a line of thunderstorms approaches the Missouri River. DISCUSSION...Over the past hour, convective intensity has largely waned across much of WW 302 - mainly due to an acceleration of an undercutting outflow boundary/cold pool expansion. The anticipated upscale growth into a more linear cluster does not appear to be materializing as expected; however, convective development continues along an eastward migrating cold front, including embedded supercells based on KLSX imagery. Nearly straight hodographs above 1 km (as sampled by the KLSX VWP) with deep-layer shear vectors somewhat orthogonal to the front will continue to promote line-embedded supercells as this activity begins to propagate east/southeast along a diffuse buoyancy gradient (which is roughly situated along the MO river). The severe threat for much of WW 302 will continue to diminish amid the onset of nocturnal cooling and further cold pool expansion to the north of the St. Louis area, but a more focused severe threat may persist downstream for the next hour or so with an attendant risk of large hail and damaging winds. ..Moore.. 05/25/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...PAH...LSX...SGF... LAT...LON 38279191 38599123 38909060 38889020 38588975 38198943 37818946 37548997 37449040 37489084 37669130 37959184 38089203 38279191 Read more

WW 0303 Status Updates
STATUS REPORT ON WW 303 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 10 S TYR TO 20 N TYR TO 5 SW DEQ TO 45 W HOT. ..BROYLES..05/25/24 ATTN...WFO...TSA...SHV...LZK...OUN...FWD...EWX...SJT... STATUS REPORT FOR WS 303 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ARC011-013-019-025-027-039-043-057-061-073-081-091-099-103-133- 139-250540- AR . ARKANSAS COUNTIES INCLUDED ARE BRADLEY CALHOUN CLARK CLEVELAND COLUMBIA DALLAS DREW HEMPSTEAD HOWARD LAFAYETTE LITTLE RIVER MILLER NEVADA OUACHITA SEVIER UNION TXC005-037-063-067-073-183-203-315-343-347-365-401-403-405-419- 423-449-459-250540- TX . TEXAS COUNTIES INCLUDED ARE ANGELINA BOWIE CAMP CASS CHEROKEE GREGG HARRISON MARION MORRIS NACOGDOCHES PANOLA RUSK SABINE SAN AUGUSTINE SHELBY Read more

WW 0303 Status Updates
STATUS REPORT ON WW 303 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 10 S TYR TO 20 N TYR TO 5 SW DEQ TO 45 W HOT. ..BROYLES..05/25/24 ATTN...WFO...TSA...SHV...LZK...OUN...FWD...EWX...SJT... STATUS REPORT FOR WS 303 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ARC011-013-019-025-027-039-043-057-061-073-081-091-099-103-133- 139-250540- AR . ARKANSAS COUNTIES INCLUDED ARE BRADLEY CALHOUN CLARK CLEVELAND COLUMBIA DALLAS DREW HEMPSTEAD HOWARD LAFAYETTE LITTLE RIVER MILLER NEVADA OUACHITA SEVIER UNION TXC005-037-063-067-073-183-203-315-343-347-365-401-403-405-419- 423-449-459-250540- TX . TEXAS COUNTIES INCLUDED ARE ANGELINA BOWIE CAMP CASS CHEROKEE GREGG HARRISON MARION MORRIS NACOGDOCHES PANOLA RUSK SABINE SAN AUGUSTINE SHELBY Read more

WW 0303 Status Updates
STATUS REPORT ON WW 303 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 5 ESE BWD TO 30 W CRS TO 20 NE PRX TO 20 SE MLC TO 35 SSE CQB. ..BROYLES..05/25/24 ATTN...WFO...TSA...SHV...LZK...OUN...FWD...EWX...SJT... STATUS REPORT FOR WS 303 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ARC007-011-013-015-019-025-027-033-039-043-047-053-057-059-061- 073-081-083-087-091-099-103-109-113-127-131-133-139-143- 250340- AR . ARKANSAS COUNTIES INCLUDED ARE BENTON BRADLEY CALHOUN CARROLL CLARK CLEVELAND COLUMBIA CRAWFORD DALLAS DREW FRANKLIN GRANT HEMPSTEAD HOT SPRING HOWARD LAFAYETTE LITTLE RIVER LOGAN MADISON MILLER NEVADA OUACHITA PIKE POLK SCOTT SEBASTIAN SEVIER UNION WASHINGTON OKC001-021-061-077-079-089-091-101-121-127-135-250340- OK . OKLAHOMA COUNTIES INCLUDED ARE ADAIR CHEROKEE HASKELL Read more

WW 0303 Status Updates
STATUS REPORT ON WW 303 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 5 ESE BWD TO 30 W CRS TO 20 NE PRX TO 20 SE MLC TO 35 SSE CQB. ..BROYLES..05/25/24 ATTN...WFO...TSA...SHV...LZK...OUN...FWD...EWX...SJT... STATUS REPORT FOR WS 303 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ARC007-011-013-015-019-025-027-033-039-043-047-053-057-059-061- 073-081-083-087-091-099-103-109-113-127-131-133-139-143- 250340- AR . ARKANSAS COUNTIES INCLUDED ARE BENTON BRADLEY CALHOUN CARROLL CLARK CLEVELAND COLUMBIA CRAWFORD DALLAS DREW FRANKLIN GRANT HEMPSTEAD HOT SPRING HOWARD LAFAYETTE LITTLE RIVER LOGAN MADISON MILLER NEVADA OUACHITA PIKE POLK SCOTT SEBASTIAN SEVIER UNION WASHINGTON OKC001-021-061-077-079-089-091-101-121-127-135-250340- OK . OKLAHOMA COUNTIES INCLUDED ARE ADAIR CHEROKEE HASKELL Read more

WW 303 SEVERE TSTM AR OK TX 242010Z - 250300Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 303 NWS Storm Prediction Center Norman OK 310 PM CDT Fri May 24 2024 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Western Arkansas Eastern Oklahoma North and Central Texas * Effective this Friday afternoon and evening from 310 PM until 1000 PM CDT. * Primary threats include... Scattered large hail likely with isolated very large hail events to 4 inches in diameter possible Scattered damaging winds and isolated significant gusts to 75 mph possible A tornado or two possible SUMMARY...Isolated to scattered severe storms are expected to develop across the region through late afternoon and early evening, including supercells capable of very large hail. A few storm clusters with an increased damaging wind risk may evolve by early evening within a very unstable environment. The severe thunderstorm watch area is approximately along and 80 statute miles east and west of a line from 40 miles north of Fayetteville AR to 50 miles southwest of Temple TX. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU3). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Severe Thunderstorm Watch means conditions are favorable for severe thunderstorms in and close to the watch area. Persons in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings. Severe thunderstorms can and occasionally do produce tornadoes. && OTHER WATCH INFORMATION...CONTINUE...WW 302... AVIATION...A few severe thunderstorms with hail surface and aloft to 4 inches. Extreme turbulence and surface wind gusts to 65 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 26025. ...Guyer Read more

MD 0943 CONCERNING SEVERE THUNDERSTORM WATCH 303... FOR SOUTHWESTERN ARKANSAS
Mesoscale Discussion 0943 NWS Storm Prediction Center Norman OK 0749 PM CDT Fri May 24 2024 Areas affected...Southwestern Arkansas Concerning...Severe Thunderstorm Watch 303... Valid 250049Z - 250245Z The severe weather threat for Severe Thunderstorm Watch 303 continues. SUMMARY...The severe threat is likely to increase across southern Arkansas. The primary threats will be large hail and wind damage, although a tornado could also occur. A watch extension in area has been done to account for the severe threat. DISCUSSION...The latest hi-resolution radar imagery from Shreveport, LA shows a cluster of strong to severe storms just to the northwest of Texarkana with at least one relatively intense supercell. Ahead of the cluster, surface dewpoints are in the mid to upper 70s, and MLCAPE is estimated by the RAP in the 3000 to 4000 J/kg range, and confirmed by the 00Z sounding at Shreveport. In addition, the latest WSR-88D VWP at Shreveport has 0-6 km shear near 45 knots with 0-3 km storm-relative helicity around 225 m2/s2. This environment suggests that supercells may be accompanied may have an isolated tornado threat. However, the greatest potential for severe will be associated with large hail and wind damage. Short-term models move the storms eastward across southern Arkansas and keep the threat going for a few more hours. ..Broyles/Thompson.. 05/25/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LZK...SHV... LAT...LON 33969358 33739401 33469417 33219405 33069357 32999311 33149284 33629277 33979313 33969358 Read more

MD 0942 CONCERNING SEVERE THUNDERSTORM WATCH 304... FOR SOUTHWEST MISSOURI
Mesoscale Discussion 0942 NWS Storm Prediction Center Norman OK 0703 PM CDT Fri May 24 2024 Areas affected...Southwest Missouri Concerning...Severe Thunderstorm Watch 304... Valid 250003Z - 250200Z The severe weather threat for Severe Thunderstorm Watch 304 continues. SUMMARY...The severe threat across southwest Missouri may be maximized over the next couple of hours. The primary threats remain large hail and damaging wind gusts. DISCUSSION...Despite numerous early attempts at convective initiation, only a few robust convective cells have been sustained over the past hour or so across southwest MO. This may be attributed to a gradually slowing frontal motion (and thus weakening forcing for ascent) across the region as stronger synoptic lift glances the region to the north. Regardless, MRMS and GOES IR imagery show a couple of robust supercells have become established and may persist for the next 1-2 hours as they migrate across an MLCAPE buoyancy axis. The KSGF VWP has recently sampled realtively weak (20 knots or less) winds in the 0-2 km layer with stronger (~40 knot) winds between 5-6 km. Consequently, regional hodographs appear to be sufficiently elongated to continue to support supercells, and should remain so through mid/late evening. Large hail (possibly up to 2 inches in diameter) and damaging winds remain the most probable hazards given the poor low-level hodograph structure. It remains unclear how long cells will persist into south-central MO later this evening, and additional storms appear possible based on recent visible imagery trends along the front (though perhaps not probable given the approaching onset of nocturnal cooling). Regardless, the severe threat should be focused to two to three cells heading into the late evening. ..Moore.. 05/25/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...SGF... LAT...LON 36669301 36629362 36669400 36779417 37009430 37109421 37409379 37829330 38059279 38119244 38059218 37809196 37419194 37039217 36809254 36669301 Read more

WW 0304 Status Updates
STATUS REPORT ON WW 304 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 15 S GMJ TO 25 NW SGF TO 20 E COU. ..MOORE..05/25/24 ATTN...WFO...SGF... STATUS REPORT FOR WS 304 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MOC009-029-043-059-065-067-077-091-105-109-119-125-131-149-153- 161-167-169-203-209-213-215-225-229-250240- MO . MISSOURI COUNTIES INCLUDED ARE BARRY CAMDEN CHRISTIAN DALLAS DENT DOUGLAS GREENE HOWELL LACLEDE LAWRENCE MCDONALD MARIES MILLER OREGON OZARK PHELPS POLK PULASKI SHANNON STONE TANEY TEXAS WEBSTER WRIGHT THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more

WW 0304 Status Updates
STATUS REPORT ON WW 304 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 15 S GMJ TO 25 NW SGF TO 20 E COU. ..MOORE..05/25/24 ATTN...WFO...SGF... STATUS REPORT FOR WS 304 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MOC009-029-043-059-065-067-077-091-105-109-119-125-131-149-153- 161-167-169-203-209-213-215-225-229-250240- MO . MISSOURI COUNTIES INCLUDED ARE BARRY CAMDEN CHRISTIAN DALLAS DENT DOUGLAS GREENE HOWELL LACLEDE LAWRENCE MCDONALD MARIES MILLER OREGON OZARK PHELPS POLK PULASKI SHANNON STONE TANEY TEXAS WEBSTER WRIGHT THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more