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SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0220 PM CDT Thu May 15 2025 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE SOUTHERN PLAINS INTO ARKANSAS...AND OVER PARTS OF THE MID-ATLANTIC AND NORTHEAST... ...SUMMARY... Severe thunderstorms are possible Saturday across parts of the Mid Atlantic and Northeast, and across parts of the southeastern Great Plains to Lower Mississippi Valley. ...Synopsis... An upper cyclone and attendant shortwave trough over the upper Great Lakes to the TN Valley will shift east on Saturday, becoming positioned from NY to offshore the Mid-Atlantic coast by Sunday morning. Meanwhile, an upper trough will dig across the western U.S. while upper ridging develops over much of the Plains. A belt of strong westerly flow associated with the eastern upper trough will overspread much of eastern U.S., while a sub-tropical jet streak moves across the southern Plain into the Lower MS Valley. At the surface, a cold front will surge east across the Ohio Valley through early afternoon, and the Mid-Atlantic and Northeast during the evening/overnight. The southwest extent of this surface boundary will extend from the Lower OH Valley into central OK Saturday morning. The boundary may sag southward across portions of the TN Valley, while the Plains portion of the boundary lifts northward into KS and southern MO during the evening/overnight. Meanwhile, a surface dryline will extend south/southwest from near western OK to the TX Big Bend vicinity. ...Southern Plains to Lower MS Valley... The building upper ridge over the Plains will likely suppress convection across portions of the region as an EML will be difficult to overcome without stronger large-scale ascent/height falls. However, low-level convergence along the dryline amid persistent low-level warm advection and forecast shortwave perturbations migrating through the upper ridge from the southern Rockies into the Red River vicinity may aid in isolated to widely scattered storm development during the afternoon. A very moist airmass will be in place (upper 60s/low 70s F dewpoints) beneath 7.5-8.5 C/km midlevel lapse rates. This will result in strong instability across the warm sector (MLCAPE greater than 2500 J/kg). Furthermore, supercell wind profiles are apparent in forecast soundings, with curved low-level hodographs become elongated/straight above 2-3 km. Any discrete cells that develop will pose a risk for large to very large hail. If sufficient storm coverage occurs, some clustering could result in upscale developing into an MCS moving across the ArkLaTex vicinity and into the Lower MS Valley during the evening/nighttime hours. If this occurs, a risk for damaging gusts will increase. ...Southeast... Convection may be ongoing/weakening across portions of MS/AL/GA/SC/NC Saturday morning. It is unclear how this activity may evolve, but an outflow boundary will likely extend across portions of MS/AL/GA. Given a very moist and unstable airmass by afternoon some redevelopment of thunderstorms is possible. Forcing for ascent will be nebulous across the Deep South, so coverage may remain sparse. Nevertheless, any storm that develops could produce strong gusts or hail. ...NC/VA into the Northeast... Convection may be ongoing across portions of NC/VA Saturday morning but likely will be weakening as outflow is expected to be surging across the Piedmont. It is unclear if redevelopment may occur ahead of the surface cold front during the afternoon/evening. While a very moist and unstable airmass will reside across the region, large-scale ascent will remain weak and focused further north toward the Northeast. If storms can develop, a risk for large hail and damaging gusts will be possible. Additional storms are expected to develop with northward extent into the Northeast beneath the upper low and ahead of the surface cold front. While boundary layer moisture will be more modest with northward extent, cool temperatures aloft will foster modest destabilization. Isolated to widely scattered storms will pose a risk for hail and gusty winds through early evening. ..Leitman.. 05/15/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0220 PM CDT Thu May 15 2025 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE SOUTHERN PLAINS INTO ARKANSAS...AND OVER PARTS OF THE MID-ATLANTIC AND NORTHEAST... ...SUMMARY... Severe thunderstorms are possible Saturday across parts of the Mid Atlantic and Northeast, and across parts of the southeastern Great Plains to Lower Mississippi Valley. ...Synopsis... An upper cyclone and attendant shortwave trough over the upper Great Lakes to the TN Valley will shift east on Saturday, becoming positioned from NY to offshore the Mid-Atlantic coast by Sunday morning. Meanwhile, an upper trough will dig across the western U.S. while upper ridging develops over much of the Plains. A belt of strong westerly flow associated with the eastern upper trough will overspread much of eastern U.S., while a sub-tropical jet streak moves across the southern Plain into the Lower MS Valley. At the surface, a cold front will surge east across the Ohio Valley through early afternoon, and the Mid-Atlantic and Northeast during the evening/overnight. The southwest extent of this surface boundary will extend from the Lower OH Valley into central OK Saturday morning. The boundary may sag southward across portions of the TN Valley, while the Plains portion of the boundary lifts northward into KS and southern MO during the evening/overnight. Meanwhile, a surface dryline will extend south/southwest from near western OK to the TX Big Bend vicinity. ...Southern Plains to Lower MS Valley... The building upper ridge over the Plains will likely suppress convection across portions of the region as an EML will be difficult to overcome without stronger large-scale ascent/height falls. However, low-level convergence along the dryline amid persistent low-level warm advection and forecast shortwave perturbations migrating through the upper ridge from the southern Rockies into the Red River vicinity may aid in isolated to widely scattered storm development during the afternoon. A very moist airmass will be in place (upper 60s/low 70s F dewpoints) beneath 7.5-8.5 C/km midlevel lapse rates. This will result in strong instability across the warm sector (MLCAPE greater than 2500 J/kg). Furthermore, supercell wind profiles are apparent in forecast soundings, with curved low-level hodographs become elongated/straight above 2-3 km. Any discrete cells that develop will pose a risk for large to very large hail. If sufficient storm coverage occurs, some clustering could result in upscale developing into an MCS moving across the ArkLaTex vicinity and into the Lower MS Valley during the evening/nighttime hours. If this occurs, a risk for damaging gusts will increase. ...Southeast... Convection may be ongoing/weakening across portions of MS/AL/GA/SC/NC Saturday morning. It is unclear how this activity may evolve, but an outflow boundary will likely extend across portions of MS/AL/GA. Given a very moist and unstable airmass by afternoon some redevelopment of thunderstorms is possible. Forcing for ascent will be nebulous across the Deep South, so coverage may remain sparse. Nevertheless, any storm that develops could produce strong gusts or hail. ...NC/VA into the Northeast... Convection may be ongoing across portions of NC/VA Saturday morning but likely will be weakening as outflow is expected to be surging across the Piedmont. It is unclear if redevelopment may occur ahead of the surface cold front during the afternoon/evening. While a very moist and unstable airmass will reside across the region, large-scale ascent will remain weak and focused further north toward the Northeast. If storms can develop, a risk for large hail and damaging gusts will be possible. Additional storms are expected to develop with northward extent into the Northeast beneath the upper low and ahead of the surface cold front. While boundary layer moisture will be more modest with northward extent, cool temperatures aloft will foster modest destabilization. Isolated to widely scattered storms will pose a risk for hail and gusty winds through early evening. ..Leitman.. 05/15/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0220 PM CDT Thu May 15 2025 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE SOUTHERN PLAINS INTO ARKANSAS...AND OVER PARTS OF THE MID-ATLANTIC AND NORTHEAST... ...SUMMARY... Severe thunderstorms are possible Saturday across parts of the Mid Atlantic and Northeast, and across parts of the southeastern Great Plains to Lower Mississippi Valley. ...Synopsis... An upper cyclone and attendant shortwave trough over the upper Great Lakes to the TN Valley will shift east on Saturday, becoming positioned from NY to offshore the Mid-Atlantic coast by Sunday morning. Meanwhile, an upper trough will dig across the western U.S. while upper ridging develops over much of the Plains. A belt of strong westerly flow associated with the eastern upper trough will overspread much of eastern U.S., while a sub-tropical jet streak moves across the southern Plain into the Lower MS Valley. At the surface, a cold front will surge east across the Ohio Valley through early afternoon, and the Mid-Atlantic and Northeast during the evening/overnight. The southwest extent of this surface boundary will extend from the Lower OH Valley into central OK Saturday morning. The boundary may sag southward across portions of the TN Valley, while the Plains portion of the boundary lifts northward into KS and southern MO during the evening/overnight. Meanwhile, a surface dryline will extend south/southwest from near western OK to the TX Big Bend vicinity. ...Southern Plains to Lower MS Valley... The building upper ridge over the Plains will likely suppress convection across portions of the region as an EML will be difficult to overcome without stronger large-scale ascent/height falls. However, low-level convergence along the dryline amid persistent low-level warm advection and forecast shortwave perturbations migrating through the upper ridge from the southern Rockies into the Red River vicinity may aid in isolated to widely scattered storm development during the afternoon. A very moist airmass will be in place (upper 60s/low 70s F dewpoints) beneath 7.5-8.5 C/km midlevel lapse rates. This will result in strong instability across the warm sector (MLCAPE greater than 2500 J/kg). Furthermore, supercell wind profiles are apparent in forecast soundings, with curved low-level hodographs become elongated/straight above 2-3 km. Any discrete cells that develop will pose a risk for large to very large hail. If sufficient storm coverage occurs, some clustering could result in upscale developing into an MCS moving across the ArkLaTex vicinity and into the Lower MS Valley during the evening/nighttime hours. If this occurs, a risk for damaging gusts will increase. ...Southeast... Convection may be ongoing/weakening across portions of MS/AL/GA/SC/NC Saturday morning. It is unclear how this activity may evolve, but an outflow boundary will likely extend across portions of MS/AL/GA. Given a very moist and unstable airmass by afternoon some redevelopment of thunderstorms is possible. Forcing for ascent will be nebulous across the Deep South, so coverage may remain sparse. Nevertheless, any storm that develops could produce strong gusts or hail. ...NC/VA into the Northeast... Convection may be ongoing across portions of NC/VA Saturday morning but likely will be weakening as outflow is expected to be surging across the Piedmont. It is unclear if redevelopment may occur ahead of the surface cold front during the afternoon/evening. While a very moist and unstable airmass will reside across the region, large-scale ascent will remain weak and focused further north toward the Northeast. If storms can develop, a risk for large hail and damaging gusts will be possible. Additional storms are expected to develop with northward extent into the Northeast beneath the upper low and ahead of the surface cold front. While boundary layer moisture will be more modest with northward extent, cool temperatures aloft will foster modest destabilization. Isolated to widely scattered storms will pose a risk for hail and gusty winds through early evening. ..Leitman.. 05/15/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0220 PM CDT Thu May 15 2025 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE SOUTHERN PLAINS INTO ARKANSAS...AND OVER PARTS OF THE MID-ATLANTIC AND NORTHEAST... ...SUMMARY... Severe thunderstorms are possible Saturday across parts of the Mid Atlantic and Northeast, and across parts of the southeastern Great Plains to Lower Mississippi Valley. ...Synopsis... An upper cyclone and attendant shortwave trough over the upper Great Lakes to the TN Valley will shift east on Saturday, becoming positioned from NY to offshore the Mid-Atlantic coast by Sunday morning. Meanwhile, an upper trough will dig across the western U.S. while upper ridging develops over much of the Plains. A belt of strong westerly flow associated with the eastern upper trough will overspread much of eastern U.S., while a sub-tropical jet streak moves across the southern Plain into the Lower MS Valley. At the surface, a cold front will surge east across the Ohio Valley through early afternoon, and the Mid-Atlantic and Northeast during the evening/overnight. The southwest extent of this surface boundary will extend from the Lower OH Valley into central OK Saturday morning. The boundary may sag southward across portions of the TN Valley, while the Plains portion of the boundary lifts northward into KS and southern MO during the evening/overnight. Meanwhile, a surface dryline will extend south/southwest from near western OK to the TX Big Bend vicinity. ...Southern Plains to Lower MS Valley... The building upper ridge over the Plains will likely suppress convection across portions of the region as an EML will be difficult to overcome without stronger large-scale ascent/height falls. However, low-level convergence along the dryline amid persistent low-level warm advection and forecast shortwave perturbations migrating through the upper ridge from the southern Rockies into the Red River vicinity may aid in isolated to widely scattered storm development during the afternoon. A very moist airmass will be in place (upper 60s/low 70s F dewpoints) beneath 7.5-8.5 C/km midlevel lapse rates. This will result in strong instability across the warm sector (MLCAPE greater than 2500 J/kg). Furthermore, supercell wind profiles are apparent in forecast soundings, with curved low-level hodographs become elongated/straight above 2-3 km. Any discrete cells that develop will pose a risk for large to very large hail. If sufficient storm coverage occurs, some clustering could result in upscale developing into an MCS moving across the ArkLaTex vicinity and into the Lower MS Valley during the evening/nighttime hours. If this occurs, a risk for damaging gusts will increase. ...Southeast... Convection may be ongoing/weakening across portions of MS/AL/GA/SC/NC Saturday morning. It is unclear how this activity may evolve, but an outflow boundary will likely extend across portions of MS/AL/GA. Given a very moist and unstable airmass by afternoon some redevelopment of thunderstorms is possible. Forcing for ascent will be nebulous across the Deep South, so coverage may remain sparse. Nevertheless, any storm that develops could produce strong gusts or hail. ...NC/VA into the Northeast... Convection may be ongoing across portions of NC/VA Saturday morning but likely will be weakening as outflow is expected to be surging across the Piedmont. It is unclear if redevelopment may occur ahead of the surface cold front during the afternoon/evening. While a very moist and unstable airmass will reside across the region, large-scale ascent will remain weak and focused further north toward the Northeast. If storms can develop, a risk for large hail and damaging gusts will be possible. Additional storms are expected to develop with northward extent into the Northeast beneath the upper low and ahead of the surface cold front. While boundary layer moisture will be more modest with northward extent, cool temperatures aloft will foster modest destabilization. Isolated to widely scattered storms will pose a risk for hail and gusty winds through early evening. ..Leitman.. 05/15/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0220 PM CDT Thu May 15 2025 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE SOUTHERN PLAINS INTO ARKANSAS...AND OVER PARTS OF THE MID-ATLANTIC AND NORTHEAST... ...SUMMARY... Severe thunderstorms are possible Saturday across parts of the Mid Atlantic and Northeast, and across parts of the southeastern Great Plains to Lower Mississippi Valley. ...Synopsis... An upper cyclone and attendant shortwave trough over the upper Great Lakes to the TN Valley will shift east on Saturday, becoming positioned from NY to offshore the Mid-Atlantic coast by Sunday morning. Meanwhile, an upper trough will dig across the western U.S. while upper ridging develops over much of the Plains. A belt of strong westerly flow associated with the eastern upper trough will overspread much of eastern U.S., while a sub-tropical jet streak moves across the southern Plain into the Lower MS Valley. At the surface, a cold front will surge east across the Ohio Valley through early afternoon, and the Mid-Atlantic and Northeast during the evening/overnight. The southwest extent of this surface boundary will extend from the Lower OH Valley into central OK Saturday morning. The boundary may sag southward across portions of the TN Valley, while the Plains portion of the boundary lifts northward into KS and southern MO during the evening/overnight. Meanwhile, a surface dryline will extend south/southwest from near western OK to the TX Big Bend vicinity. ...Southern Plains to Lower MS Valley... The building upper ridge over the Plains will likely suppress convection across portions of the region as an EML will be difficult to overcome without stronger large-scale ascent/height falls. However, low-level convergence along the dryline amid persistent low-level warm advection and forecast shortwave perturbations migrating through the upper ridge from the southern Rockies into the Red River vicinity may aid in isolated to widely scattered storm development during the afternoon. A very moist airmass will be in place (upper 60s/low 70s F dewpoints) beneath 7.5-8.5 C/km midlevel lapse rates. This will result in strong instability across the warm sector (MLCAPE greater than 2500 J/kg). Furthermore, supercell wind profiles are apparent in forecast soundings, with curved low-level hodographs become elongated/straight above 2-3 km. Any discrete cells that develop will pose a risk for large to very large hail. If sufficient storm coverage occurs, some clustering could result in upscale developing into an MCS moving across the ArkLaTex vicinity and into the Lower MS Valley during the evening/nighttime hours. If this occurs, a risk for damaging gusts will increase. ...Southeast... Convection may be ongoing/weakening across portions of MS/AL/GA/SC/NC Saturday morning. It is unclear how this activity may evolve, but an outflow boundary will likely extend across portions of MS/AL/GA. Given a very moist and unstable airmass by afternoon some redevelopment of thunderstorms is possible. Forcing for ascent will be nebulous across the Deep South, so coverage may remain sparse. Nevertheless, any storm that develops could produce strong gusts or hail. ...NC/VA into the Northeast... Convection may be ongoing across portions of NC/VA Saturday morning but likely will be weakening as outflow is expected to be surging across the Piedmont. It is unclear if redevelopment may occur ahead of the surface cold front during the afternoon/evening. While a very moist and unstable airmass will reside across the region, large-scale ascent will remain weak and focused further north toward the Northeast. If storms can develop, a risk for large hail and damaging gusts will be possible. Additional storms are expected to develop with northward extent into the Northeast beneath the upper low and ahead of the surface cold front. While boundary layer moisture will be more modest with northward extent, cool temperatures aloft will foster modest destabilization. Isolated to widely scattered storms will pose a risk for hail and gusty winds through early evening. ..Leitman.. 05/15/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0220 PM CDT Thu May 15 2025 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE SOUTHERN PLAINS INTO ARKANSAS...AND OVER PARTS OF THE MID-ATLANTIC AND NORTHEAST... ...SUMMARY... Severe thunderstorms are possible Saturday across parts of the Mid Atlantic and Northeast, and across parts of the southeastern Great Plains to Lower Mississippi Valley. ...Synopsis... An upper cyclone and attendant shortwave trough over the upper Great Lakes to the TN Valley will shift east on Saturday, becoming positioned from NY to offshore the Mid-Atlantic coast by Sunday morning. Meanwhile, an upper trough will dig across the western U.S. while upper ridging develops over much of the Plains. A belt of strong westerly flow associated with the eastern upper trough will overspread much of eastern U.S., while a sub-tropical jet streak moves across the southern Plain into the Lower MS Valley. At the surface, a cold front will surge east across the Ohio Valley through early afternoon, and the Mid-Atlantic and Northeast during the evening/overnight. The southwest extent of this surface boundary will extend from the Lower OH Valley into central OK Saturday morning. The boundary may sag southward across portions of the TN Valley, while the Plains portion of the boundary lifts northward into KS and southern MO during the evening/overnight. Meanwhile, a surface dryline will extend south/southwest from near western OK to the TX Big Bend vicinity. ...Southern Plains to Lower MS Valley... The building upper ridge over the Plains will likely suppress convection across portions of the region as an EML will be difficult to overcome without stronger large-scale ascent/height falls. However, low-level convergence along the dryline amid persistent low-level warm advection and forecast shortwave perturbations migrating through the upper ridge from the southern Rockies into the Red River vicinity may aid in isolated to widely scattered storm development during the afternoon. A very moist airmass will be in place (upper 60s/low 70s F dewpoints) beneath 7.5-8.5 C/km midlevel lapse rates. This will result in strong instability across the warm sector (MLCAPE greater than 2500 J/kg). Furthermore, supercell wind profiles are apparent in forecast soundings, with curved low-level hodographs become elongated/straight above 2-3 km. Any discrete cells that develop will pose a risk for large to very large hail. If sufficient storm coverage occurs, some clustering could result in upscale developing into an MCS moving across the ArkLaTex vicinity and into the Lower MS Valley during the evening/nighttime hours. If this occurs, a risk for damaging gusts will increase. ...Southeast... Convection may be ongoing/weakening across portions of MS/AL/GA/SC/NC Saturday morning. It is unclear how this activity may evolve, but an outflow boundary will likely extend across portions of MS/AL/GA. Given a very moist and unstable airmass by afternoon some redevelopment of thunderstorms is possible. Forcing for ascent will be nebulous across the Deep South, so coverage may remain sparse. Nevertheless, any storm that develops could produce strong gusts or hail. ...NC/VA into the Northeast... Convection may be ongoing across portions of NC/VA Saturday morning but likely will be weakening as outflow is expected to be surging across the Piedmont. It is unclear if redevelopment may occur ahead of the surface cold front during the afternoon/evening. While a very moist and unstable airmass will reside across the region, large-scale ascent will remain weak and focused further north toward the Northeast. If storms can develop, a risk for large hail and damaging gusts will be possible. Additional storms are expected to develop with northward extent into the Northeast beneath the upper low and ahead of the surface cold front. While boundary layer moisture will be more modest with northward extent, cool temperatures aloft will foster modest destabilization. Isolated to widely scattered storms will pose a risk for hail and gusty winds through early evening. ..Leitman.. 05/15/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0220 PM CDT Thu May 15 2025 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE SOUTHERN PLAINS INTO ARKANSAS...AND OVER PARTS OF THE MID-ATLANTIC AND NORTHEAST... ...SUMMARY... Severe thunderstorms are possible Saturday across parts of the Mid Atlantic and Northeast, and across parts of the southeastern Great Plains to Lower Mississippi Valley. ...Synopsis... An upper cyclone and attendant shortwave trough over the upper Great Lakes to the TN Valley will shift east on Saturday, becoming positioned from NY to offshore the Mid-Atlantic coast by Sunday morning. Meanwhile, an upper trough will dig across the western U.S. while upper ridging develops over much of the Plains. A belt of strong westerly flow associated with the eastern upper trough will overspread much of eastern U.S., while a sub-tropical jet streak moves across the southern Plain into the Lower MS Valley. At the surface, a cold front will surge east across the Ohio Valley through early afternoon, and the Mid-Atlantic and Northeast during the evening/overnight. The southwest extent of this surface boundary will extend from the Lower OH Valley into central OK Saturday morning. The boundary may sag southward across portions of the TN Valley, while the Plains portion of the boundary lifts northward into KS and southern MO during the evening/overnight. Meanwhile, a surface dryline will extend south/southwest from near western OK to the TX Big Bend vicinity. ...Southern Plains to Lower MS Valley... The building upper ridge over the Plains will likely suppress convection across portions of the region as an EML will be difficult to overcome without stronger large-scale ascent/height falls. However, low-level convergence along the dryline amid persistent low-level warm advection and forecast shortwave perturbations migrating through the upper ridge from the southern Rockies into the Red River vicinity may aid in isolated to widely scattered storm development during the afternoon. A very moist airmass will be in place (upper 60s/low 70s F dewpoints) beneath 7.5-8.5 C/km midlevel lapse rates. This will result in strong instability across the warm sector (MLCAPE greater than 2500 J/kg). Furthermore, supercell wind profiles are apparent in forecast soundings, with curved low-level hodographs become elongated/straight above 2-3 km. Any discrete cells that develop will pose a risk for large to very large hail. If sufficient storm coverage occurs, some clustering could result in upscale developing into an MCS moving across the ArkLaTex vicinity and into the Lower MS Valley during the evening/nighttime hours. If this occurs, a risk for damaging gusts will increase. ...Southeast... Convection may be ongoing/weakening across portions of MS/AL/GA/SC/NC Saturday morning. It is unclear how this activity may evolve, but an outflow boundary will likely extend across portions of MS/AL/GA. Given a very moist and unstable airmass by afternoon some redevelopment of thunderstorms is possible. Forcing for ascent will be nebulous across the Deep South, so coverage may remain sparse. Nevertheless, any storm that develops could produce strong gusts or hail. ...NC/VA into the Northeast... Convection may be ongoing across portions of NC/VA Saturday morning but likely will be weakening as outflow is expected to be surging across the Piedmont. It is unclear if redevelopment may occur ahead of the surface cold front during the afternoon/evening. While a very moist and unstable airmass will reside across the region, large-scale ascent will remain weak and focused further north toward the Northeast. If storms can develop, a risk for large hail and damaging gusts will be possible. Additional storms are expected to develop with northward extent into the Northeast beneath the upper low and ahead of the surface cold front. While boundary layer moisture will be more modest with northward extent, cool temperatures aloft will foster modest destabilization. Isolated to widely scattered storms will pose a risk for hail and gusty winds through early evening. ..Leitman.. 05/15/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0220 PM CDT Thu May 15 2025 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE SOUTHERN PLAINS INTO ARKANSAS...AND OVER PARTS OF THE MID-ATLANTIC AND NORTHEAST... ...SUMMARY... Severe thunderstorms are possible Saturday across parts of the Mid Atlantic and Northeast, and across parts of the southeastern Great Plains to Lower Mississippi Valley. ...Synopsis... An upper cyclone and attendant shortwave trough over the upper Great Lakes to the TN Valley will shift east on Saturday, becoming positioned from NY to offshore the Mid-Atlantic coast by Sunday morning. Meanwhile, an upper trough will dig across the western U.S. while upper ridging develops over much of the Plains. A belt of strong westerly flow associated with the eastern upper trough will overspread much of eastern U.S., while a sub-tropical jet streak moves across the southern Plain into the Lower MS Valley. At the surface, a cold front will surge east across the Ohio Valley through early afternoon, and the Mid-Atlantic and Northeast during the evening/overnight. The southwest extent of this surface boundary will extend from the Lower OH Valley into central OK Saturday morning. The boundary may sag southward across portions of the TN Valley, while the Plains portion of the boundary lifts northward into KS and southern MO during the evening/overnight. Meanwhile, a surface dryline will extend south/southwest from near western OK to the TX Big Bend vicinity. ...Southern Plains to Lower MS Valley... The building upper ridge over the Plains will likely suppress convection across portions of the region as an EML will be difficult to overcome without stronger large-scale ascent/height falls. However, low-level convergence along the dryline amid persistent low-level warm advection and forecast shortwave perturbations migrating through the upper ridge from the southern Rockies into the Red River vicinity may aid in isolated to widely scattered storm development during the afternoon. A very moist airmass will be in place (upper 60s/low 70s F dewpoints) beneath 7.5-8.5 C/km midlevel lapse rates. This will result in strong instability across the warm sector (MLCAPE greater than 2500 J/kg). Furthermore, supercell wind profiles are apparent in forecast soundings, with curved low-level hodographs become elongated/straight above 2-3 km. Any discrete cells that develop will pose a risk for large to very large hail. If sufficient storm coverage occurs, some clustering could result in upscale developing into an MCS moving across the ArkLaTex vicinity and into the Lower MS Valley during the evening/nighttime hours. If this occurs, a risk for damaging gusts will increase. ...Southeast... Convection may be ongoing/weakening across portions of MS/AL/GA/SC/NC Saturday morning. It is unclear how this activity may evolve, but an outflow boundary will likely extend across portions of MS/AL/GA. Given a very moist and unstable airmass by afternoon some redevelopment of thunderstorms is possible. Forcing for ascent will be nebulous across the Deep South, so coverage may remain sparse. Nevertheless, any storm that develops could produce strong gusts or hail. ...NC/VA into the Northeast... Convection may be ongoing across portions of NC/VA Saturday morning but likely will be weakening as outflow is expected to be surging across the Piedmont. It is unclear if redevelopment may occur ahead of the surface cold front during the afternoon/evening. While a very moist and unstable airmass will reside across the region, large-scale ascent will remain weak and focused further north toward the Northeast. If storms can develop, a risk for large hail and damaging gusts will be possible. Additional storms are expected to develop with northward extent into the Northeast beneath the upper low and ahead of the surface cold front. While boundary layer moisture will be more modest with northward extent, cool temperatures aloft will foster modest destabilization. Isolated to widely scattered storms will pose a risk for hail and gusty winds through early evening. ..Leitman.. 05/15/2025 Read more

MD 0787 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR PORTIONS OF CENTRAL AND NORTHERN ARKANSAS INTO FAR SOUTHEASTERN MISSOURI
Mesoscale Discussion 0787 NWS Storm Prediction Center Norman OK 1255 PM CDT Thu May 15 2025 Areas affected...portions of central and northern Arkansas into far southeastern Missouri Concerning...Severe potential...Watch possible Valid 151755Z - 151930Z Probability of Watch Issuance...40 percent SUMMARY...The severe threat may increase into the afternoon if storms can become surface based. Severe hail and wind are the main concerns. Should storm increase in coverage/intensity, and root into the boundary layer, a Severe Thunderstorm Watch may be needed. DISCUSSION...Scattered thunderstorms ahead of a cold front persist atop a stout capping layer, and have fluctuated in intensity over the past few hours. Ahead of these storms, the boundary layer continues to destabilize as surface temperatures warm into the mid 80s F, amid 70+ F dewpoints beneath 8-9 C/km mid-level lapse rates, yielding 2000+ J/kg MLCAPE. 50-70 kts of 500 mb southwesterly flow supports over 50 kts of effective bulk shear. Hodographs via RAP forecast soundings are relatively straight, suggesting that multicells and splitting supercell structures will be the primary mode of convection, assuming storms can become surface based. Latest mesoanalysis and RAP forecast soundings show that a substantial degree of convective inhibition remains, so it is plausible that the ongoing storms may not intensify further, at least for a while. However, if storms manage to become surface based, a more prominent severe hail/wind threat may materialize, at which point a Severe Thunderstorm Watch may be needed. ..Squitieri/Mosier.. 05/15/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...PAH...MEG...LSX...LZK...SGF...TSA... LAT...LON 34669451 35699311 36429213 37079085 36898998 36158984 35279026 35019055 34649154 34459234 34459365 34669451 MOST PROBABLE PEAK WIND GUST...65-80 MPH MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN Read more

MD 0786 CONCERNING SEVERE POTENTIAL...WATCH LIKELY FOR PORTIONS OF SOUTHERN AND CENTRAL MINNESOTA INTO NORTHWEST WISCONSIN
Mesoscale Discussion 0786 NWS Storm Prediction Center Norman OK 1208 PM CDT Thu May 15 2025 Areas affected...Portions of southern and central Minnesota into Northwest Wisconsin Concerning...Severe potential...Watch likely Valid 151708Z - 151945Z Probability of Watch Issuance...80 percent SUMMARY...Severe storms capable of all severe hazards (including very large hail and strong tornadoes) are expected this afternoon. Timing of storm development is uncertain, but one or more watches are likely early this afternoon. DISCUSSION...Potent mid-level ascent continues to lift into southern and central Minnesota late this morning. Earlier elevated convection north of the Twin Cities has weakened substantially and very minimal outflow is evident from that activity. A narrow warm sector is lifting ahead of a dryline feature. Despite cloud cover, temperatures continue to warm into the low/mid 70s F and cumulus are beginning to deepen along the dryline. Given the forcing for ascent, initiation of stronger storms within the next 2-3 hours appears reasonable and is supported by most recent CAM guidance. Strong effective shear across the surface boundaries should support at least initially discrete storms. Strong forcing aloft may promote some areas of quicker upscale growth into line segments. Mid-level lapse rates advecting into the region will support large/very large hail. Low-level southeasterly winds will promote large low-level hodographs (already evident on the KMPX VAD). Tornadoes, some potentially strong, will be possible. The tornado risk will likely be greater with southeastward extent on account of the broader warm sector. Scattered severe gusts are also expected given convective transport of strong low-level flow to the surface. The timing of development remains the biggest uncertainty along with the relatively narrow zone of tornado risk in Minnesota. One ore more watches are likely early this afternoon. ..Wendt/Mosier.. 05/15/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...DLH...ARX...MPX...FGF... LAT...LON 44109429 45039564 45879603 46339554 46449406 45999278 45559214 44569190 43879237 43579286 44109429 MOST PROBABLE PEAK TORNADO INTENSITY...100-130 MPH MOST PROBABLE PEAK WIND GUST...55-70 MPH MOST PROBABLE PEAK HAIL SIZE...2.00-3.50 IN Read more

WW 0252 Status Updates
STATUS FOR WATCH 0252 HAS NOT BEEN ISSUED YET Read more

WW 0252 Status Updates
STATUS FOR WATCH 0252 HAS NOT BEEN ISSUED YET Read more

WW 0251 Status Updates
STATUS FOR WATCH 0251 HAS NOT BEEN ISSUED YET Read more

WW 0251 Status Updates
STATUS FOR WATCH 0251 HAS NOT BEEN ISSUED YET Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1220 PM CDT Thu May 15 2025 Valid 161200Z - 171200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTHEAST MISSOURI...SOUTHERN ILLINOIS/INDIANA...AND CENTRAL AND WESTERN KENTUCKY... ...SUMMARY... A regional outbreak of severe thunderstorms is likely across parts of the middle Mississippi and Ohio Valleys Friday afternoon into Friday night. This may include a few intense supercells posing a risk for large hail and tornadoes. During the evening into the overnight hours, this will include an upscale growing and organizing bowing line of storms posing a risk for strong, damaging winds and a continuing risk for tornadoes. ...A regional outbreak of severe storms is expected on Friday across portions of the Mid-South to the Ohio Valley... ...Synopsis... An upper cyclone over the Upper Midwest and attendant shortwave trough will develop east/northeast across much of the Midwest and TN Valley. A swath of strong mid/upper southwesterly flow will accompany this system. Forecast guidance shows a 70-90 kt 500 mb jet spreading across the Mid-MS to OH Valley, while 850-700 mb increases to 40-60 kt by midday. This will result in supercell wind profiles, support widespread organized convection. Favorable deep-layer shear will extend downstream into the central Appalachians and Mid-Atlantic vicinity as well. At the surface, low pressure will shift east from northern MN into the Upper Great Lakes. A warm from southern MO into the OH Valley Friday morning is forecast to lift northward through the afternoon, allowing rich boundary layer moisture (mid/upper 60s F dewpoints) to overspread much of the Lower OH Valley, with a large warm sector in place across a broad region from east TX to the Great Lakes and eastward toward the Mid-Atlantic coast. Corridors of moderate to strong destabilization during the day and into the nighttime hours will support several areas of severe storms from east Texas into much of the Midwest and the Mid-Atlantic, some of which could be significant. ...Mid-MS Valley into the OH/TN Valley Vicinity... Forecast guidance depicts potential for remnant convection from Day 1/Thu ongoing across KY or TN Friday morning. Current expectation is that this activity will dissipate or weaken as it shifts east toward the central Appalachians. Strong warm advection should allow for rapid airmass recovery in the way of any morning thunderstorm activity. By midday, a very moist (mid 60s to low 70s F dewpoints) airmass will be in place beneath steep midlevel lapse rates, fostering MLCAPE around 2500-3500 J/kg from southeast MO northward to around the I-70 corridor and east toward the IN/KY. One or more clusters of convection is expected to develop by early afternoon within the strong warm advection regime and as large-scale ascent increases with the approach of the upper trough and an eastward-advancing cold front extending from eastern IA/western MO into central OK/TX around midday. Supercell wind profiles with enlarged low-level hodographs becoming elongated above 2-3 km within a volatile thermodynamic environment suggests convection will rapidly intensify. Any convection that remains discrete will pose a risk for very large hail (up to 3.5 inches), tornadoes (a few may be strong), and damaging gusts. With time, consolidation of thunderstorm clusters is expected and an organized bow is forecast to move across the OH/TN Valley region. Intense, damaging gusts greater than 70 kt will be possible once this occurs. Additional convection is expected to develop during the evening ahead of the advancing cold front from northern AR into western TN/KY. If this activity can remain discrete, supercells will pose an all-hazards severe risk. Eventually, this activity should become linear, but will still have an attendant wind/tornado risk, with a gradual weakening trend during the overnight hours expected across MS/AL/GA. ...Central Appalachians to Mid-Atlantic... Thunderstorms may be ongoing Friday morning across parts of PA and spread east/southeast through early afternoon as a lead upper shortwave impulse moves across the Northeast. Moistening and heating ahead of this activity will support moderate to strong destabilization, especially from the Chesapeake Bay vicinity southward across the VA/NC Piedmont. The initial round of thunderstorms may pose a risk for locally strong gusts and hail before moving offshore the NJ/DE/MD coast during the early afternoon. During the evening/overnight hours, a mature bowing MCS is expected to move over the WV/VA/NC mountains and spread east across the region, posing a risk for swaths of strong to damaging wind gusts. Forecast guidance varies in timing and exact evolution of this system across the region, but portions of the area may need higher probabilities in subsequent outlooks. ...WI/MI... Thunderstorms are expected to develop ahead of the surface low and cold front during the afternoon and evening. Cold temperatures aloft will support steep midlevel lapse rates and weak to moderate instability despite more modest boundary layer moisture. Favorable shear will support organized convection capable of isolated damaging gusts and hail. ...ArkLaTex vicinity... A more conditional risk of significant severe thunderstorms will exist across northeast TX into southern AR/northwest LA. A very moist and strongly unstable airmass will be in place, and forecast guidance suggests capping should erode along/ahead of the surface dryline. Low-level convergence along the surface boundary is not expected to be strong, and large-scale ascent will be nebulous, with neutral height tendencies expected. Nevertheless, at least a few storms are expected to develop during/just after peak heating. Supercell wind profiles, with long/straight hodographs are apparent in forecast soundings. Furthermore, thermodynamic profiles will be very favorable for large hail, while steepening low-level lapse rates will support strong outflow winds. Isolated significant hail (to 2.5 inches) is possible in addition to sporadic damaging gusts. ..Leitman.. 05/15/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1220 PM CDT Thu May 15 2025 Valid 161200Z - 171200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTHEAST MISSOURI...SOUTHERN ILLINOIS/INDIANA...AND CENTRAL AND WESTERN KENTUCKY... ...SUMMARY... A regional outbreak of severe thunderstorms is likely across parts of the middle Mississippi and Ohio Valleys Friday afternoon into Friday night. This may include a few intense supercells posing a risk for large hail and tornadoes. During the evening into the overnight hours, this will include an upscale growing and organizing bowing line of storms posing a risk for strong, damaging winds and a continuing risk for tornadoes. ...A regional outbreak of severe storms is expected on Friday across portions of the Mid-South to the Ohio Valley... ...Synopsis... An upper cyclone over the Upper Midwest and attendant shortwave trough will develop east/northeast across much of the Midwest and TN Valley. A swath of strong mid/upper southwesterly flow will accompany this system. Forecast guidance shows a 70-90 kt 500 mb jet spreading across the Mid-MS to OH Valley, while 850-700 mb increases to 40-60 kt by midday. This will result in supercell wind profiles, support widespread organized convection. Favorable deep-layer shear will extend downstream into the central Appalachians and Mid-Atlantic vicinity as well. At the surface, low pressure will shift east from northern MN into the Upper Great Lakes. A warm from southern MO into the OH Valley Friday morning is forecast to lift northward through the afternoon, allowing rich boundary layer moisture (mid/upper 60s F dewpoints) to overspread much of the Lower OH Valley, with a large warm sector in place across a broad region from east TX to the Great Lakes and eastward toward the Mid-Atlantic coast. Corridors of moderate to strong destabilization during the day and into the nighttime hours will support several areas of severe storms from east Texas into much of the Midwest and the Mid-Atlantic, some of which could be significant. ...Mid-MS Valley into the OH/TN Valley Vicinity... Forecast guidance depicts potential for remnant convection from Day 1/Thu ongoing across KY or TN Friday morning. Current expectation is that this activity will dissipate or weaken as it shifts east toward the central Appalachians. Strong warm advection should allow for rapid airmass recovery in the way of any morning thunderstorm activity. By midday, a very moist (mid 60s to low 70s F dewpoints) airmass will be in place beneath steep midlevel lapse rates, fostering MLCAPE around 2500-3500 J/kg from southeast MO northward to around the I-70 corridor and east toward the IN/KY. One or more clusters of convection is expected to develop by early afternoon within the strong warm advection regime and as large-scale ascent increases with the approach of the upper trough and an eastward-advancing cold front extending from eastern IA/western MO into central OK/TX around midday. Supercell wind profiles with enlarged low-level hodographs becoming elongated above 2-3 km within a volatile thermodynamic environment suggests convection will rapidly intensify. Any convection that remains discrete will pose a risk for very large hail (up to 3.5 inches), tornadoes (a few may be strong), and damaging gusts. With time, consolidation of thunderstorm clusters is expected and an organized bow is forecast to move across the OH/TN Valley region. Intense, damaging gusts greater than 70 kt will be possible once this occurs. Additional convection is expected to develop during the evening ahead of the advancing cold front from northern AR into western TN/KY. If this activity can remain discrete, supercells will pose an all-hazards severe risk. Eventually, this activity should become linear, but will still have an attendant wind/tornado risk, with a gradual weakening trend during the overnight hours expected across MS/AL/GA. ...Central Appalachians to Mid-Atlantic... Thunderstorms may be ongoing Friday morning across parts of PA and spread east/southeast through early afternoon as a lead upper shortwave impulse moves across the Northeast. Moistening and heating ahead of this activity will support moderate to strong destabilization, especially from the Chesapeake Bay vicinity southward across the VA/NC Piedmont. The initial round of thunderstorms may pose a risk for locally strong gusts and hail before moving offshore the NJ/DE/MD coast during the early afternoon. During the evening/overnight hours, a mature bowing MCS is expected to move over the WV/VA/NC mountains and spread east across the region, posing a risk for swaths of strong to damaging wind gusts. Forecast guidance varies in timing and exact evolution of this system across the region, but portions of the area may need higher probabilities in subsequent outlooks. ...WI/MI... Thunderstorms are expected to develop ahead of the surface low and cold front during the afternoon and evening. Cold temperatures aloft will support steep midlevel lapse rates and weak to moderate instability despite more modest boundary layer moisture. Favorable shear will support organized convection capable of isolated damaging gusts and hail. ...ArkLaTex vicinity... A more conditional risk of significant severe thunderstorms will exist across northeast TX into southern AR/northwest LA. A very moist and strongly unstable airmass will be in place, and forecast guidance suggests capping should erode along/ahead of the surface dryline. Low-level convergence along the surface boundary is not expected to be strong, and large-scale ascent will be nebulous, with neutral height tendencies expected. Nevertheless, at least a few storms are expected to develop during/just after peak heating. Supercell wind profiles, with long/straight hodographs are apparent in forecast soundings. Furthermore, thermodynamic profiles will be very favorable for large hail, while steepening low-level lapse rates will support strong outflow winds. Isolated significant hail (to 2.5 inches) is possible in addition to sporadic damaging gusts. ..Leitman.. 05/15/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1220 PM CDT Thu May 15 2025 Valid 161200Z - 171200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTHEAST MISSOURI...SOUTHERN ILLINOIS/INDIANA...AND CENTRAL AND WESTERN KENTUCKY... ...SUMMARY... A regional outbreak of severe thunderstorms is likely across parts of the middle Mississippi and Ohio Valleys Friday afternoon into Friday night. This may include a few intense supercells posing a risk for large hail and tornadoes. During the evening into the overnight hours, this will include an upscale growing and organizing bowing line of storms posing a risk for strong, damaging winds and a continuing risk for tornadoes. ...A regional outbreak of severe storms is expected on Friday across portions of the Mid-South to the Ohio Valley... ...Synopsis... An upper cyclone over the Upper Midwest and attendant shortwave trough will develop east/northeast across much of the Midwest and TN Valley. A swath of strong mid/upper southwesterly flow will accompany this system. Forecast guidance shows a 70-90 kt 500 mb jet spreading across the Mid-MS to OH Valley, while 850-700 mb increases to 40-60 kt by midday. This will result in supercell wind profiles, support widespread organized convection. Favorable deep-layer shear will extend downstream into the central Appalachians and Mid-Atlantic vicinity as well. At the surface, low pressure will shift east from northern MN into the Upper Great Lakes. A warm from southern MO into the OH Valley Friday morning is forecast to lift northward through the afternoon, allowing rich boundary layer moisture (mid/upper 60s F dewpoints) to overspread much of the Lower OH Valley, with a large warm sector in place across a broad region from east TX to the Great Lakes and eastward toward the Mid-Atlantic coast. Corridors of moderate to strong destabilization during the day and into the nighttime hours will support several areas of severe storms from east Texas into much of the Midwest and the Mid-Atlantic, some of which could be significant. ...Mid-MS Valley into the OH/TN Valley Vicinity... Forecast guidance depicts potential for remnant convection from Day 1/Thu ongoing across KY or TN Friday morning. Current expectation is that this activity will dissipate or weaken as it shifts east toward the central Appalachians. Strong warm advection should allow for rapid airmass recovery in the way of any morning thunderstorm activity. By midday, a very moist (mid 60s to low 70s F dewpoints) airmass will be in place beneath steep midlevel lapse rates, fostering MLCAPE around 2500-3500 J/kg from southeast MO northward to around the I-70 corridor and east toward the IN/KY. One or more clusters of convection is expected to develop by early afternoon within the strong warm advection regime and as large-scale ascent increases with the approach of the upper trough and an eastward-advancing cold front extending from eastern IA/western MO into central OK/TX around midday. Supercell wind profiles with enlarged low-level hodographs becoming elongated above 2-3 km within a volatile thermodynamic environment suggests convection will rapidly intensify. Any convection that remains discrete will pose a risk for very large hail (up to 3.5 inches), tornadoes (a few may be strong), and damaging gusts. With time, consolidation of thunderstorm clusters is expected and an organized bow is forecast to move across the OH/TN Valley region. Intense, damaging gusts greater than 70 kt will be possible once this occurs. Additional convection is expected to develop during the evening ahead of the advancing cold front from northern AR into western TN/KY. If this activity can remain discrete, supercells will pose an all-hazards severe risk. Eventually, this activity should become linear, but will still have an attendant wind/tornado risk, with a gradual weakening trend during the overnight hours expected across MS/AL/GA. ...Central Appalachians to Mid-Atlantic... Thunderstorms may be ongoing Friday morning across parts of PA and spread east/southeast through early afternoon as a lead upper shortwave impulse moves across the Northeast. Moistening and heating ahead of this activity will support moderate to strong destabilization, especially from the Chesapeake Bay vicinity southward across the VA/NC Piedmont. The initial round of thunderstorms may pose a risk for locally strong gusts and hail before moving offshore the NJ/DE/MD coast during the early afternoon. During the evening/overnight hours, a mature bowing MCS is expected to move over the WV/VA/NC mountains and spread east across the region, posing a risk for swaths of strong to damaging wind gusts. Forecast guidance varies in timing and exact evolution of this system across the region, but portions of the area may need higher probabilities in subsequent outlooks. ...WI/MI... Thunderstorms are expected to develop ahead of the surface low and cold front during the afternoon and evening. Cold temperatures aloft will support steep midlevel lapse rates and weak to moderate instability despite more modest boundary layer moisture. Favorable shear will support organized convection capable of isolated damaging gusts and hail. ...ArkLaTex vicinity... A more conditional risk of significant severe thunderstorms will exist across northeast TX into southern AR/northwest LA. A very moist and strongly unstable airmass will be in place, and forecast guidance suggests capping should erode along/ahead of the surface dryline. Low-level convergence along the surface boundary is not expected to be strong, and large-scale ascent will be nebulous, with neutral height tendencies expected. Nevertheless, at least a few storms are expected to develop during/just after peak heating. Supercell wind profiles, with long/straight hodographs are apparent in forecast soundings. Furthermore, thermodynamic profiles will be very favorable for large hail, while steepening low-level lapse rates will support strong outflow winds. Isolated significant hail (to 2.5 inches) is possible in addition to sporadic damaging gusts. ..Leitman.. 05/15/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1220 PM CDT Thu May 15 2025 Valid 161200Z - 171200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTHEAST MISSOURI...SOUTHERN ILLINOIS/INDIANA...AND CENTRAL AND WESTERN KENTUCKY... ...SUMMARY... A regional outbreak of severe thunderstorms is likely across parts of the middle Mississippi and Ohio Valleys Friday afternoon into Friday night. This may include a few intense supercells posing a risk for large hail and tornadoes. During the evening into the overnight hours, this will include an upscale growing and organizing bowing line of storms posing a risk for strong, damaging winds and a continuing risk for tornadoes. ...A regional outbreak of severe storms is expected on Friday across portions of the Mid-South to the Ohio Valley... ...Synopsis... An upper cyclone over the Upper Midwest and attendant shortwave trough will develop east/northeast across much of the Midwest and TN Valley. A swath of strong mid/upper southwesterly flow will accompany this system. Forecast guidance shows a 70-90 kt 500 mb jet spreading across the Mid-MS to OH Valley, while 850-700 mb increases to 40-60 kt by midday. This will result in supercell wind profiles, support widespread organized convection. Favorable deep-layer shear will extend downstream into the central Appalachians and Mid-Atlantic vicinity as well. At the surface, low pressure will shift east from northern MN into the Upper Great Lakes. A warm from southern MO into the OH Valley Friday morning is forecast to lift northward through the afternoon, allowing rich boundary layer moisture (mid/upper 60s F dewpoints) to overspread much of the Lower OH Valley, with a large warm sector in place across a broad region from east TX to the Great Lakes and eastward toward the Mid-Atlantic coast. Corridors of moderate to strong destabilization during the day and into the nighttime hours will support several areas of severe storms from east Texas into much of the Midwest and the Mid-Atlantic, some of which could be significant. ...Mid-MS Valley into the OH/TN Valley Vicinity... Forecast guidance depicts potential for remnant convection from Day 1/Thu ongoing across KY or TN Friday morning. Current expectation is that this activity will dissipate or weaken as it shifts east toward the central Appalachians. Strong warm advection should allow for rapid airmass recovery in the way of any morning thunderstorm activity. By midday, a very moist (mid 60s to low 70s F dewpoints) airmass will be in place beneath steep midlevel lapse rates, fostering MLCAPE around 2500-3500 J/kg from southeast MO northward to around the I-70 corridor and east toward the IN/KY. One or more clusters of convection is expected to develop by early afternoon within the strong warm advection regime and as large-scale ascent increases with the approach of the upper trough and an eastward-advancing cold front extending from eastern IA/western MO into central OK/TX around midday. Supercell wind profiles with enlarged low-level hodographs becoming elongated above 2-3 km within a volatile thermodynamic environment suggests convection will rapidly intensify. Any convection that remains discrete will pose a risk for very large hail (up to 3.5 inches), tornadoes (a few may be strong), and damaging gusts. With time, consolidation of thunderstorm clusters is expected and an organized bow is forecast to move across the OH/TN Valley region. Intense, damaging gusts greater than 70 kt will be possible once this occurs. Additional convection is expected to develop during the evening ahead of the advancing cold front from northern AR into western TN/KY. If this activity can remain discrete, supercells will pose an all-hazards severe risk. Eventually, this activity should become linear, but will still have an attendant wind/tornado risk, with a gradual weakening trend during the overnight hours expected across MS/AL/GA. ...Central Appalachians to Mid-Atlantic... Thunderstorms may be ongoing Friday morning across parts of PA and spread east/southeast through early afternoon as a lead upper shortwave impulse moves across the Northeast. Moistening and heating ahead of this activity will support moderate to strong destabilization, especially from the Chesapeake Bay vicinity southward across the VA/NC Piedmont. The initial round of thunderstorms may pose a risk for locally strong gusts and hail before moving offshore the NJ/DE/MD coast during the early afternoon. During the evening/overnight hours, a mature bowing MCS is expected to move over the WV/VA/NC mountains and spread east across the region, posing a risk for swaths of strong to damaging wind gusts. Forecast guidance varies in timing and exact evolution of this system across the region, but portions of the area may need higher probabilities in subsequent outlooks. ...WI/MI... Thunderstorms are expected to develop ahead of the surface low and cold front during the afternoon and evening. Cold temperatures aloft will support steep midlevel lapse rates and weak to moderate instability despite more modest boundary layer moisture. Favorable shear will support organized convection capable of isolated damaging gusts and hail. ...ArkLaTex vicinity... A more conditional risk of significant severe thunderstorms will exist across northeast TX into southern AR/northwest LA. A very moist and strongly unstable airmass will be in place, and forecast guidance suggests capping should erode along/ahead of the surface dryline. Low-level convergence along the surface boundary is not expected to be strong, and large-scale ascent will be nebulous, with neutral height tendencies expected. Nevertheless, at least a few storms are expected to develop during/just after peak heating. Supercell wind profiles, with long/straight hodographs are apparent in forecast soundings. Furthermore, thermodynamic profiles will be very favorable for large hail, while steepening low-level lapse rates will support strong outflow winds. Isolated significant hail (to 2.5 inches) is possible in addition to sporadic damaging gusts. ..Leitman.. 05/15/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1220 PM CDT Thu May 15 2025 Valid 161200Z - 171200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTHEAST MISSOURI...SOUTHERN ILLINOIS/INDIANA...AND CENTRAL AND WESTERN KENTUCKY... ...SUMMARY... A regional outbreak of severe thunderstorms is likely across parts of the middle Mississippi and Ohio Valleys Friday afternoon into Friday night. This may include a few intense supercells posing a risk for large hail and tornadoes. During the evening into the overnight hours, this will include an upscale growing and organizing bowing line of storms posing a risk for strong, damaging winds and a continuing risk for tornadoes. ...A regional outbreak of severe storms is expected on Friday across portions of the Mid-South to the Ohio Valley... ...Synopsis... An upper cyclone over the Upper Midwest and attendant shortwave trough will develop east/northeast across much of the Midwest and TN Valley. A swath of strong mid/upper southwesterly flow will accompany this system. Forecast guidance shows a 70-90 kt 500 mb jet spreading across the Mid-MS to OH Valley, while 850-700 mb increases to 40-60 kt by midday. This will result in supercell wind profiles, support widespread organized convection. Favorable deep-layer shear will extend downstream into the central Appalachians and Mid-Atlantic vicinity as well. At the surface, low pressure will shift east from northern MN into the Upper Great Lakes. A warm from southern MO into the OH Valley Friday morning is forecast to lift northward through the afternoon, allowing rich boundary layer moisture (mid/upper 60s F dewpoints) to overspread much of the Lower OH Valley, with a large warm sector in place across a broad region from east TX to the Great Lakes and eastward toward the Mid-Atlantic coast. Corridors of moderate to strong destabilization during the day and into the nighttime hours will support several areas of severe storms from east Texas into much of the Midwest and the Mid-Atlantic, some of which could be significant. ...Mid-MS Valley into the OH/TN Valley Vicinity... Forecast guidance depicts potential for remnant convection from Day 1/Thu ongoing across KY or TN Friday morning. Current expectation is that this activity will dissipate or weaken as it shifts east toward the central Appalachians. Strong warm advection should allow for rapid airmass recovery in the way of any morning thunderstorm activity. By midday, a very moist (mid 60s to low 70s F dewpoints) airmass will be in place beneath steep midlevel lapse rates, fostering MLCAPE around 2500-3500 J/kg from southeast MO northward to around the I-70 corridor and east toward the IN/KY. One or more clusters of convection is expected to develop by early afternoon within the strong warm advection regime and as large-scale ascent increases with the approach of the upper trough and an eastward-advancing cold front extending from eastern IA/western MO into central OK/TX around midday. Supercell wind profiles with enlarged low-level hodographs becoming elongated above 2-3 km within a volatile thermodynamic environment suggests convection will rapidly intensify. Any convection that remains discrete will pose a risk for very large hail (up to 3.5 inches), tornadoes (a few may be strong), and damaging gusts. With time, consolidation of thunderstorm clusters is expected and an organized bow is forecast to move across the OH/TN Valley region. Intense, damaging gusts greater than 70 kt will be possible once this occurs. Additional convection is expected to develop during the evening ahead of the advancing cold front from northern AR into western TN/KY. If this activity can remain discrete, supercells will pose an all-hazards severe risk. Eventually, this activity should become linear, but will still have an attendant wind/tornado risk, with a gradual weakening trend during the overnight hours expected across MS/AL/GA. ...Central Appalachians to Mid-Atlantic... Thunderstorms may be ongoing Friday morning across parts of PA and spread east/southeast through early afternoon as a lead upper shortwave impulse moves across the Northeast. Moistening and heating ahead of this activity will support moderate to strong destabilization, especially from the Chesapeake Bay vicinity southward across the VA/NC Piedmont. The initial round of thunderstorms may pose a risk for locally strong gusts and hail before moving offshore the NJ/DE/MD coast during the early afternoon. During the evening/overnight hours, a mature bowing MCS is expected to move over the WV/VA/NC mountains and spread east across the region, posing a risk for swaths of strong to damaging wind gusts. Forecast guidance varies in timing and exact evolution of this system across the region, but portions of the area may need higher probabilities in subsequent outlooks. ...WI/MI... Thunderstorms are expected to develop ahead of the surface low and cold front during the afternoon and evening. Cold temperatures aloft will support steep midlevel lapse rates and weak to moderate instability despite more modest boundary layer moisture. Favorable shear will support organized convection capable of isolated damaging gusts and hail. ...ArkLaTex vicinity... A more conditional risk of significant severe thunderstorms will exist across northeast TX into southern AR/northwest LA. A very moist and strongly unstable airmass will be in place, and forecast guidance suggests capping should erode along/ahead of the surface dryline. Low-level convergence along the surface boundary is not expected to be strong, and large-scale ascent will be nebulous, with neutral height tendencies expected. Nevertheless, at least a few storms are expected to develop during/just after peak heating. Supercell wind profiles, with long/straight hodographs are apparent in forecast soundings. Furthermore, thermodynamic profiles will be very favorable for large hail, while steepening low-level lapse rates will support strong outflow winds. Isolated significant hail (to 2.5 inches) is possible in addition to sporadic damaging gusts. ..Leitman.. 05/15/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1220 PM CDT Thu May 15 2025 Valid 161200Z - 171200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTHEAST MISSOURI...SOUTHERN ILLINOIS/INDIANA...AND CENTRAL AND WESTERN KENTUCKY... ...SUMMARY... A regional outbreak of severe thunderstorms is likely across parts of the middle Mississippi and Ohio Valleys Friday afternoon into Friday night. This may include a few intense supercells posing a risk for large hail and tornadoes. During the evening into the overnight hours, this will include an upscale growing and organizing bowing line of storms posing a risk for strong, damaging winds and a continuing risk for tornadoes. ...A regional outbreak of severe storms is expected on Friday across portions of the Mid-South to the Ohio Valley... ...Synopsis... An upper cyclone over the Upper Midwest and attendant shortwave trough will develop east/northeast across much of the Midwest and TN Valley. A swath of strong mid/upper southwesterly flow will accompany this system. Forecast guidance shows a 70-90 kt 500 mb jet spreading across the Mid-MS to OH Valley, while 850-700 mb increases to 40-60 kt by midday. This will result in supercell wind profiles, support widespread organized convection. Favorable deep-layer shear will extend downstream into the central Appalachians and Mid-Atlantic vicinity as well. At the surface, low pressure will shift east from northern MN into the Upper Great Lakes. A warm from southern MO into the OH Valley Friday morning is forecast to lift northward through the afternoon, allowing rich boundary layer moisture (mid/upper 60s F dewpoints) to overspread much of the Lower OH Valley, with a large warm sector in place across a broad region from east TX to the Great Lakes and eastward toward the Mid-Atlantic coast. Corridors of moderate to strong destabilization during the day and into the nighttime hours will support several areas of severe storms from east Texas into much of the Midwest and the Mid-Atlantic, some of which could be significant. ...Mid-MS Valley into the OH/TN Valley Vicinity... Forecast guidance depicts potential for remnant convection from Day 1/Thu ongoing across KY or TN Friday morning. Current expectation is that this activity will dissipate or weaken as it shifts east toward the central Appalachians. Strong warm advection should allow for rapid airmass recovery in the way of any morning thunderstorm activity. By midday, a very moist (mid 60s to low 70s F dewpoints) airmass will be in place beneath steep midlevel lapse rates, fostering MLCAPE around 2500-3500 J/kg from southeast MO northward to around the I-70 corridor and east toward the IN/KY. One or more clusters of convection is expected to develop by early afternoon within the strong warm advection regime and as large-scale ascent increases with the approach of the upper trough and an eastward-advancing cold front extending from eastern IA/western MO into central OK/TX around midday. Supercell wind profiles with enlarged low-level hodographs becoming elongated above 2-3 km within a volatile thermodynamic environment suggests convection will rapidly intensify. Any convection that remains discrete will pose a risk for very large hail (up to 3.5 inches), tornadoes (a few may be strong), and damaging gusts. With time, consolidation of thunderstorm clusters is expected and an organized bow is forecast to move across the OH/TN Valley region. Intense, damaging gusts greater than 70 kt will be possible once this occurs. Additional convection is expected to develop during the evening ahead of the advancing cold front from northern AR into western TN/KY. If this activity can remain discrete, supercells will pose an all-hazards severe risk. Eventually, this activity should become linear, but will still have an attendant wind/tornado risk, with a gradual weakening trend during the overnight hours expected across MS/AL/GA. ...Central Appalachians to Mid-Atlantic... Thunderstorms may be ongoing Friday morning across parts of PA and spread east/southeast through early afternoon as a lead upper shortwave impulse moves across the Northeast. Moistening and heating ahead of this activity will support moderate to strong destabilization, especially from the Chesapeake Bay vicinity southward across the VA/NC Piedmont. The initial round of thunderstorms may pose a risk for locally strong gusts and hail before moving offshore the NJ/DE/MD coast during the early afternoon. During the evening/overnight hours, a mature bowing MCS is expected to move over the WV/VA/NC mountains and spread east across the region, posing a risk for swaths of strong to damaging wind gusts. Forecast guidance varies in timing and exact evolution of this system across the region, but portions of the area may need higher probabilities in subsequent outlooks. ...WI/MI... Thunderstorms are expected to develop ahead of the surface low and cold front during the afternoon and evening. Cold temperatures aloft will support steep midlevel lapse rates and weak to moderate instability despite more modest boundary layer moisture. Favorable shear will support organized convection capable of isolated damaging gusts and hail. ...ArkLaTex vicinity... A more conditional risk of significant severe thunderstorms will exist across northeast TX into southern AR/northwest LA. A very moist and strongly unstable airmass will be in place, and forecast guidance suggests capping should erode along/ahead of the surface dryline. Low-level convergence along the surface boundary is not expected to be strong, and large-scale ascent will be nebulous, with neutral height tendencies expected. Nevertheless, at least a few storms are expected to develop during/just after peak heating. Supercell wind profiles, with long/straight hodographs are apparent in forecast soundings. Furthermore, thermodynamic profiles will be very favorable for large hail, while steepening low-level lapse rates will support strong outflow winds. Isolated significant hail (to 2.5 inches) is possible in addition to sporadic damaging gusts. ..Leitman.. 05/15/2025 Read more