Severe Storms

WW 0410 Status Updates
STATUS REPORT ON WW 410 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..DEAN..06/12/25 ATTN...WFO...BOU...LBF...CYS...FSD...ABR...UNR... STATUS REPORT FOR WS 410 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS COC075-087-095-115-123-122240- CO . COLORADO COUNTIES INCLUDED ARE LOGAN MORGAN PHILLIPS SEDGWICK WELD NEC005-007-013-017-029-031-033-045-049-069-075-091-101-103-105- 117-123-135-157-161-165-171-122240- NE . NEBRASKA COUNTIES INCLUDED ARE ARTHUR BANNER BOX BUTTE BROWN CHASE CHERRY CHEYENNE DAWES DEUEL GARDEN GRANT HOOKER KEITH KEYA PAHA KIMBALL MCPHERSON MORRILL PERKINS SCOTTS BLUFF SHERIDAN SIOUX THOMAS SDC003-015-017-023-053-073-085-095-121-123-122240- Read more

WW 0410 Status Updates
STATUS REPORT ON WW 410 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..DEAN..06/12/25 ATTN...WFO...BOU...LBF...CYS...FSD...ABR...UNR... STATUS REPORT FOR WS 410 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS COC075-087-095-115-123-122240- CO . COLORADO COUNTIES INCLUDED ARE LOGAN MORGAN PHILLIPS SEDGWICK WELD NEC005-007-013-017-029-031-033-045-049-069-075-091-101-103-105- 117-123-135-157-161-165-171-122240- NE . NEBRASKA COUNTIES INCLUDED ARE ARTHUR BANNER BOX BUTTE BROWN CHASE CHERRY CHEYENNE DAWES DEUEL GARDEN GRANT HOOKER KEITH KEYA PAHA KIMBALL MCPHERSON MORRILL PERKINS SCOTTS BLUFF SHERIDAN SIOUX THOMAS SDC003-015-017-023-053-073-085-095-121-123-122240- Read more

WW 0410 Status Updates
STATUS REPORT ON WW 410 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..DEAN..06/12/25 ATTN...WFO...BOU...LBF...CYS...FSD...ABR...UNR... STATUS REPORT FOR WS 410 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS COC075-087-095-115-123-122240- CO . COLORADO COUNTIES INCLUDED ARE LOGAN MORGAN PHILLIPS SEDGWICK WELD NEC005-007-013-017-029-031-033-045-049-069-075-091-101-103-105- 117-123-135-157-161-165-171-122240- NE . NEBRASKA COUNTIES INCLUDED ARE ARTHUR BANNER BOX BUTTE BROWN CHASE CHERRY CHEYENNE DAWES DEUEL GARDEN GRANT HOOKER KEITH KEYA PAHA KIMBALL MCPHERSON MORRILL PERKINS SCOTTS BLUFF SHERIDAN SIOUX THOMAS SDC003-015-017-023-053-073-085-095-121-123-122240- Read more

WW 410 SEVERE TSTM CO NE SD WY 122055Z - 130500Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 410 NWS Storm Prediction Center Norman OK 255 PM MDT Thu Jun 12 2025 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Northeast Colorado Western and Northern Nebraska Southern South Dakota Southeast Wyoming * Effective this Thursday afternoon and evening from 255 PM until 1100 PM MDT. * Primary threats include... Scattered large hail and isolated very large hail events to 2.5 inches in diameter possible Scattered damaging wind gusts to 70 mph possible A tornado or two possible SUMMARY...Severe thunderstorms are expected to continue to develop regionally mainly near a southwest/northeast-oriented front, with an unstable air mass and moderately strong wind profiles supporting supercells and hail/wind potential, and possibly even a brief tornado. The severe thunderstorm watch area is approximately along and 75 statute miles north and south of a line from 40 miles east southeast of Chamberlain SD to 75 miles south southwest of Torrington WY. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU0). 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. && AVIATION...A few severe thunderstorms with hail surface and aloft to 2.5 inches. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 550. Mean storm motion vector 26025. ...Guyer Read more

WW 0410 Status Updates
STATUS FOR WATCH 0410 HAS NOT BEEN ISSUED YET Read more

No watches are valid as of Thu Jun 12 20:48:01 UTC 2025.

MD 1260 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR CENTRAL/NORTHERN LOUISIANA...SOUTHERN ARKANSAS...WESTERN MISSISSIPPI
Mesoscale Discussion 1260 NWS Storm Prediction Center Norman OK 0127 PM CDT Thu Jun 12 2025 Areas affected...central/northern Louisiana...southern Arkansas...western Mississippi Concerning...Severe potential...Watch unlikely Valid 121827Z - 122030Z Probability of Watch Issuance...20 percent SUMMARY...Marginal severe threat to continue through the afternoon. DISCUSSION...Thunderstorm activity continues near an MCV across eastern TX into portion so LA/AR. Largely, this has remained below severe limits. Echo tops have increased over the last hour or so with daytime heating and increasing instability across southern LA. Overall, flow remains weak except in association with the MCV where around 20-30 kts of deep layer shear are noted on the eastern periphery. Some organization may occur with deeper updrafts with potential for damaging wind and perhaps a tornado. This corridor will shift north and eastward into AR through time this afternoon. Overall, this risk will likely remain too localized for watch issuance. ..Thornton/Guyer.. 06/12/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...JAN...LIX...LZK...LCH...SHV... LAT...LON 30599338 31889300 33029326 34289337 34579311 34379197 34039141 33499071 32299018 30779102 30499168 30139225 30219294 30599338 MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 95 MPH MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Thu Jun 12 2025 Valid 122000Z - 131200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTH-CENTRAL PLAINS... ...SUMMARY... Scattered areas of severe thunderstorm development are possible today into tonight, accompanied by potential for severe hail and wind across parts of the Great Plains, the Upper Midwest, the Texas coastal plain into the Lower Mississippi Valley, as well as a portion of the northern Mid-Atlantic. ...20z Update... The primary change for this update is to remove risk probabilities across parts of eastern TX and western LA in the wake of a gradually strengthening convective band/MCS where conditions have stabilized. Low-end risk probabilities have been expanded slightly across south TX to account for the southeastward propagation of a convective cluster developing on the outflow of the prior MCS. Recent RAP mesoanalysis estimates/forecast soundings suggest the downstream convective environment may be supportive of organized convection through early evening. Elsewhere, the forecast largely remains on track with few adjustments required. Convection developing within the upslope flow regime across the central High Plains should increase in coverage and intensity as ascent associated with a weak mid-level perturbation (currently over northern UT) overspreads the region. Across the Northern Mid-Atlantic/Northeast, temperatures have warmed into the mid-80s, which should minimize inhibition based on forecast soundings; however, satellite imagery continues to show meager vertical development of cumulus along the frontal zone, which limits confidence in convective initiation and the overall severe threat. See the previous discussion (below) and MCD #1260 for additional details. ..Moore.. 06/12/2025 .PREV DISCUSSION... /ISSUED 1151 AM CDT Thu Jun 12 2025/ ...North-central Plains including Nebraska/South Dakota... A low-amplitude shortwave trough and associated speed max will progress eastward over the northern High Plains, from southeast Montana/northeast Wyoming toward the Dakotas. Related forcing for ascent and a moderate belt of mid-level westerlies will overlie a wavy frontal zone across southern South Dakota and western Nebraska. At least widely scattered thunderstorms are expected into mid/late afternoon, with moderate buoyancy and 35-45 kt effective shear (especially northern Nebraska northward) supportive of supercells. Large hail and severe-caliber wind gusts are the primary hazards. ...South/East Texas to Lower Mississippi Valley/Mid-South... An extensive MCS and prominent outflow remain primary forecast factors today, with outflow now having progressed off the middle/upper Texas coast. An enhanced low/mid-level wind field on the eastern periphery of the convectively augmented upper low will continue to contribute to some supercell/tornado risk within a moist environment, although cloud cover and thermodynamic limitations may persist. Damaging winds may also occur on a sporadic/relatively limited basis regionally. ...Southeast/southern Appalachians... Strong heating is expected today across parts of Georgia into the Carolinas, where temperatures in the upper 80s F and dewpoints near 70F are forecast. This will lead to widespread moderate CAPE values and the development of scattered afternoon thunderstorms. Vertical shear is weak, but a few weakly organized thunderstorm clusters may reach severe intensity with gusty/damaging winds. ...Northern Mid-Atlantic/Northeast... With full insolation, moderate destabilization will steadily develop this afternoon near/south of a southward-moving front. While ingredients are severe-storm supportive, the extent of deep convective development may be limited by modest overall forcing/low-level convergence, but at least isolated damaging winds/hail will be possible where storms do develop. Favorable deep-layer shear (40+ kt effective) is conditionally supportive of well-organized storms including supercells. In a relative sense, severe storm development currently appears most probable across eastern Pennsylvania, northern New Jersey, and potentially toward the Great NYC Metro vicinity/far southeast New York. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Thu Jun 12 2025 Valid 122000Z - 131200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTH-CENTRAL PLAINS... ...SUMMARY... Scattered areas of severe thunderstorm development are possible today into tonight, accompanied by potential for severe hail and wind across parts of the Great Plains, the Upper Midwest, the Texas coastal plain into the Lower Mississippi Valley, as well as a portion of the northern Mid-Atlantic. ...20z Update... The primary change for this update is to remove risk probabilities across parts of eastern TX and western LA in the wake of a gradually strengthening convective band/MCS where conditions have stabilized. Low-end risk probabilities have been expanded slightly across south TX to account for the southeastward propagation of a convective cluster developing on the outflow of the prior MCS. Recent RAP mesoanalysis estimates/forecast soundings suggest the downstream convective environment may be supportive of organized convection through early evening. Elsewhere, the forecast largely remains on track with few adjustments required. Convection developing within the upslope flow regime across the central High Plains should increase in coverage and intensity as ascent associated with a weak mid-level perturbation (currently over northern UT) overspreads the region. Across the Northern Mid-Atlantic/Northeast, temperatures have warmed into the mid-80s, which should minimize inhibition based on forecast soundings; however, satellite imagery continues to show meager vertical development of cumulus along the frontal zone, which limits confidence in convective initiation and the overall severe threat. See the previous discussion (below) and MCD #1260 for additional details. ..Moore.. 06/12/2025 .PREV DISCUSSION... /ISSUED 1151 AM CDT Thu Jun 12 2025/ ...North-central Plains including Nebraska/South Dakota... A low-amplitude shortwave trough and associated speed max will progress eastward over the northern High Plains, from southeast Montana/northeast Wyoming toward the Dakotas. Related forcing for ascent and a moderate belt of mid-level westerlies will overlie a wavy frontal zone across southern South Dakota and western Nebraska. At least widely scattered thunderstorms are expected into mid/late afternoon, with moderate buoyancy and 35-45 kt effective shear (especially northern Nebraska northward) supportive of supercells. Large hail and severe-caliber wind gusts are the primary hazards. ...South/East Texas to Lower Mississippi Valley/Mid-South... An extensive MCS and prominent outflow remain primary forecast factors today, with outflow now having progressed off the middle/upper Texas coast. An enhanced low/mid-level wind field on the eastern periphery of the convectively augmented upper low will continue to contribute to some supercell/tornado risk within a moist environment, although cloud cover and thermodynamic limitations may persist. Damaging winds may also occur on a sporadic/relatively limited basis regionally. ...Southeast/southern Appalachians... Strong heating is expected today across parts of Georgia into the Carolinas, where temperatures in the upper 80s F and dewpoints near 70F are forecast. This will lead to widespread moderate CAPE values and the development of scattered afternoon thunderstorms. Vertical shear is weak, but a few weakly organized thunderstorm clusters may reach severe intensity with gusty/damaging winds. ...Northern Mid-Atlantic/Northeast... With full insolation, moderate destabilization will steadily develop this afternoon near/south of a southward-moving front. While ingredients are severe-storm supportive, the extent of deep convective development may be limited by modest overall forcing/low-level convergence, but at least isolated damaging winds/hail will be possible where storms do develop. Favorable deep-layer shear (40+ kt effective) is conditionally supportive of well-organized storms including supercells. In a relative sense, severe storm development currently appears most probable across eastern Pennsylvania, northern New Jersey, and potentially toward the Great NYC Metro vicinity/far southeast New York. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Thu Jun 12 2025 Valid 122000Z - 131200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTH-CENTRAL PLAINS... ...SUMMARY... Scattered areas of severe thunderstorm development are possible today into tonight, accompanied by potential for severe hail and wind across parts of the Great Plains, the Upper Midwest, the Texas coastal plain into the Lower Mississippi Valley, as well as a portion of the northern Mid-Atlantic. ...20z Update... The primary change for this update is to remove risk probabilities across parts of eastern TX and western LA in the wake of a gradually strengthening convective band/MCS where conditions have stabilized. Low-end risk probabilities have been expanded slightly across south TX to account for the southeastward propagation of a convective cluster developing on the outflow of the prior MCS. Recent RAP mesoanalysis estimates/forecast soundings suggest the downstream convective environment may be supportive of organized convection through early evening. Elsewhere, the forecast largely remains on track with few adjustments required. Convection developing within the upslope flow regime across the central High Plains should increase in coverage and intensity as ascent associated with a weak mid-level perturbation (currently over northern UT) overspreads the region. Across the Northern Mid-Atlantic/Northeast, temperatures have warmed into the mid-80s, which should minimize inhibition based on forecast soundings; however, satellite imagery continues to show meager vertical development of cumulus along the frontal zone, which limits confidence in convective initiation and the overall severe threat. See the previous discussion (below) and MCD #1260 for additional details. ..Moore.. 06/12/2025 .PREV DISCUSSION... /ISSUED 1151 AM CDT Thu Jun 12 2025/ ...North-central Plains including Nebraska/South Dakota... A low-amplitude shortwave trough and associated speed max will progress eastward over the northern High Plains, from southeast Montana/northeast Wyoming toward the Dakotas. Related forcing for ascent and a moderate belt of mid-level westerlies will overlie a wavy frontal zone across southern South Dakota and western Nebraska. At least widely scattered thunderstorms are expected into mid/late afternoon, with moderate buoyancy and 35-45 kt effective shear (especially northern Nebraska northward) supportive of supercells. Large hail and severe-caliber wind gusts are the primary hazards. ...South/East Texas to Lower Mississippi Valley/Mid-South... An extensive MCS and prominent outflow remain primary forecast factors today, with outflow now having progressed off the middle/upper Texas coast. An enhanced low/mid-level wind field on the eastern periphery of the convectively augmented upper low will continue to contribute to some supercell/tornado risk within a moist environment, although cloud cover and thermodynamic limitations may persist. Damaging winds may also occur on a sporadic/relatively limited basis regionally. ...Southeast/southern Appalachians... Strong heating is expected today across parts of Georgia into the Carolinas, where temperatures in the upper 80s F and dewpoints near 70F are forecast. This will lead to widespread moderate CAPE values and the development of scattered afternoon thunderstorms. Vertical shear is weak, but a few weakly organized thunderstorm clusters may reach severe intensity with gusty/damaging winds. ...Northern Mid-Atlantic/Northeast... With full insolation, moderate destabilization will steadily develop this afternoon near/south of a southward-moving front. While ingredients are severe-storm supportive, the extent of deep convective development may be limited by modest overall forcing/low-level convergence, but at least isolated damaging winds/hail will be possible where storms do develop. Favorable deep-layer shear (40+ kt effective) is conditionally supportive of well-organized storms including supercells. In a relative sense, severe storm development currently appears most probable across eastern Pennsylvania, northern New Jersey, and potentially toward the Great NYC Metro vicinity/far southeast New York. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Thu Jun 12 2025 Valid 122000Z - 131200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTH-CENTRAL PLAINS... ...SUMMARY... Scattered areas of severe thunderstorm development are possible today into tonight, accompanied by potential for severe hail and wind across parts of the Great Plains, the Upper Midwest, the Texas coastal plain into the Lower Mississippi Valley, as well as a portion of the northern Mid-Atlantic. ...20z Update... The primary change for this update is to remove risk probabilities across parts of eastern TX and western LA in the wake of a gradually strengthening convective band/MCS where conditions have stabilized. Low-end risk probabilities have been expanded slightly across south TX to account for the southeastward propagation of a convective cluster developing on the outflow of the prior MCS. Recent RAP mesoanalysis estimates/forecast soundings suggest the downstream convective environment may be supportive of organized convection through early evening. Elsewhere, the forecast largely remains on track with few adjustments required. Convection developing within the upslope flow regime across the central High Plains should increase in coverage and intensity as ascent associated with a weak mid-level perturbation (currently over northern UT) overspreads the region. Across the Northern Mid-Atlantic/Northeast, temperatures have warmed into the mid-80s, which should minimize inhibition based on forecast soundings; however, satellite imagery continues to show meager vertical development of cumulus along the frontal zone, which limits confidence in convective initiation and the overall severe threat. See the previous discussion (below) and MCD #1260 for additional details. ..Moore.. 06/12/2025 .PREV DISCUSSION... /ISSUED 1151 AM CDT Thu Jun 12 2025/ ...North-central Plains including Nebraska/South Dakota... A low-amplitude shortwave trough and associated speed max will progress eastward over the northern High Plains, from southeast Montana/northeast Wyoming toward the Dakotas. Related forcing for ascent and a moderate belt of mid-level westerlies will overlie a wavy frontal zone across southern South Dakota and western Nebraska. At least widely scattered thunderstorms are expected into mid/late afternoon, with moderate buoyancy and 35-45 kt effective shear (especially northern Nebraska northward) supportive of supercells. Large hail and severe-caliber wind gusts are the primary hazards. ...South/East Texas to Lower Mississippi Valley/Mid-South... An extensive MCS and prominent outflow remain primary forecast factors today, with outflow now having progressed off the middle/upper Texas coast. An enhanced low/mid-level wind field on the eastern periphery of the convectively augmented upper low will continue to contribute to some supercell/tornado risk within a moist environment, although cloud cover and thermodynamic limitations may persist. Damaging winds may also occur on a sporadic/relatively limited basis regionally. ...Southeast/southern Appalachians... Strong heating is expected today across parts of Georgia into the Carolinas, where temperatures in the upper 80s F and dewpoints near 70F are forecast. This will lead to widespread moderate CAPE values and the development of scattered afternoon thunderstorms. Vertical shear is weak, but a few weakly organized thunderstorm clusters may reach severe intensity with gusty/damaging winds. ...Northern Mid-Atlantic/Northeast... With full insolation, moderate destabilization will steadily develop this afternoon near/south of a southward-moving front. While ingredients are severe-storm supportive, the extent of deep convective development may be limited by modest overall forcing/low-level convergence, but at least isolated damaging winds/hail will be possible where storms do develop. Favorable deep-layer shear (40+ kt effective) is conditionally supportive of well-organized storms including supercells. In a relative sense, severe storm development currently appears most probable across eastern Pennsylvania, northern New Jersey, and potentially toward the Great NYC Metro vicinity/far southeast New York. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Thu Jun 12 2025 Valid 122000Z - 131200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTH-CENTRAL PLAINS... ...SUMMARY... Scattered areas of severe thunderstorm development are possible today into tonight, accompanied by potential for severe hail and wind across parts of the Great Plains, the Upper Midwest, the Texas coastal plain into the Lower Mississippi Valley, as well as a portion of the northern Mid-Atlantic. ...20z Update... The primary change for this update is to remove risk probabilities across parts of eastern TX and western LA in the wake of a gradually strengthening convective band/MCS where conditions have stabilized. Low-end risk probabilities have been expanded slightly across south TX to account for the southeastward propagation of a convective cluster developing on the outflow of the prior MCS. Recent RAP mesoanalysis estimates/forecast soundings suggest the downstream convective environment may be supportive of organized convection through early evening. Elsewhere, the forecast largely remains on track with few adjustments required. Convection developing within the upslope flow regime across the central High Plains should increase in coverage and intensity as ascent associated with a weak mid-level perturbation (currently over northern UT) overspreads the region. Across the Northern Mid-Atlantic/Northeast, temperatures have warmed into the mid-80s, which should minimize inhibition based on forecast soundings; however, satellite imagery continues to show meager vertical development of cumulus along the frontal zone, which limits confidence in convective initiation and the overall severe threat. See the previous discussion (below) and MCD #1260 for additional details. ..Moore.. 06/12/2025 .PREV DISCUSSION... /ISSUED 1151 AM CDT Thu Jun 12 2025/ ...North-central Plains including Nebraska/South Dakota... A low-amplitude shortwave trough and associated speed max will progress eastward over the northern High Plains, from southeast Montana/northeast Wyoming toward the Dakotas. Related forcing for ascent and a moderate belt of mid-level westerlies will overlie a wavy frontal zone across southern South Dakota and western Nebraska. At least widely scattered thunderstorms are expected into mid/late afternoon, with moderate buoyancy and 35-45 kt effective shear (especially northern Nebraska northward) supportive of supercells. Large hail and severe-caliber wind gusts are the primary hazards. ...South/East Texas to Lower Mississippi Valley/Mid-South... An extensive MCS and prominent outflow remain primary forecast factors today, with outflow now having progressed off the middle/upper Texas coast. An enhanced low/mid-level wind field on the eastern periphery of the convectively augmented upper low will continue to contribute to some supercell/tornado risk within a moist environment, although cloud cover and thermodynamic limitations may persist. Damaging winds may also occur on a sporadic/relatively limited basis regionally. ...Southeast/southern Appalachians... Strong heating is expected today across parts of Georgia into the Carolinas, where temperatures in the upper 80s F and dewpoints near 70F are forecast. This will lead to widespread moderate CAPE values and the development of scattered afternoon thunderstorms. Vertical shear is weak, but a few weakly organized thunderstorm clusters may reach severe intensity with gusty/damaging winds. ...Northern Mid-Atlantic/Northeast... With full insolation, moderate destabilization will steadily develop this afternoon near/south of a southward-moving front. While ingredients are severe-storm supportive, the extent of deep convective development may be limited by modest overall forcing/low-level convergence, but at least isolated damaging winds/hail will be possible where storms do develop. Favorable deep-layer shear (40+ kt effective) is conditionally supportive of well-organized storms including supercells. In a relative sense, severe storm development currently appears most probable across eastern Pennsylvania, northern New Jersey, and potentially toward the Great NYC Metro vicinity/far southeast New York. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Thu Jun 12 2025 Valid 122000Z - 131200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTH-CENTRAL PLAINS... ...SUMMARY... Scattered areas of severe thunderstorm development are possible today into tonight, accompanied by potential for severe hail and wind across parts of the Great Plains, the Upper Midwest, the Texas coastal plain into the Lower Mississippi Valley, as well as a portion of the northern Mid-Atlantic. ...20z Update... The primary change for this update is to remove risk probabilities across parts of eastern TX and western LA in the wake of a gradually strengthening convective band/MCS where conditions have stabilized. Low-end risk probabilities have been expanded slightly across south TX to account for the southeastward propagation of a convective cluster developing on the outflow of the prior MCS. Recent RAP mesoanalysis estimates/forecast soundings suggest the downstream convective environment may be supportive of organized convection through early evening. Elsewhere, the forecast largely remains on track with few adjustments required. Convection developing within the upslope flow regime across the central High Plains should increase in coverage and intensity as ascent associated with a weak mid-level perturbation (currently over northern UT) overspreads the region. Across the Northern Mid-Atlantic/Northeast, temperatures have warmed into the mid-80s, which should minimize inhibition based on forecast soundings; however, satellite imagery continues to show meager vertical development of cumulus along the frontal zone, which limits confidence in convective initiation and the overall severe threat. See the previous discussion (below) and MCD #1260 for additional details. ..Moore.. 06/12/2025 .PREV DISCUSSION... /ISSUED 1151 AM CDT Thu Jun 12 2025/ ...North-central Plains including Nebraska/South Dakota... A low-amplitude shortwave trough and associated speed max will progress eastward over the northern High Plains, from southeast Montana/northeast Wyoming toward the Dakotas. Related forcing for ascent and a moderate belt of mid-level westerlies will overlie a wavy frontal zone across southern South Dakota and western Nebraska. At least widely scattered thunderstorms are expected into mid/late afternoon, with moderate buoyancy and 35-45 kt effective shear (especially northern Nebraska northward) supportive of supercells. Large hail and severe-caliber wind gusts are the primary hazards. ...South/East Texas to Lower Mississippi Valley/Mid-South... An extensive MCS and prominent outflow remain primary forecast factors today, with outflow now having progressed off the middle/upper Texas coast. An enhanced low/mid-level wind field on the eastern periphery of the convectively augmented upper low will continue to contribute to some supercell/tornado risk within a moist environment, although cloud cover and thermodynamic limitations may persist. Damaging winds may also occur on a sporadic/relatively limited basis regionally. ...Southeast/southern Appalachians... Strong heating is expected today across parts of Georgia into the Carolinas, where temperatures in the upper 80s F and dewpoints near 70F are forecast. This will lead to widespread moderate CAPE values and the development of scattered afternoon thunderstorms. Vertical shear is weak, but a few weakly organized thunderstorm clusters may reach severe intensity with gusty/damaging winds. ...Northern Mid-Atlantic/Northeast... With full insolation, moderate destabilization will steadily develop this afternoon near/south of a southward-moving front. While ingredients are severe-storm supportive, the extent of deep convective development may be limited by modest overall forcing/low-level convergence, but at least isolated damaging winds/hail will be possible where storms do develop. Favorable deep-layer shear (40+ kt effective) is conditionally supportive of well-organized storms including supercells. In a relative sense, severe storm development currently appears most probable across eastern Pennsylvania, northern New Jersey, and potentially toward the Great NYC Metro vicinity/far southeast New York. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Thu Jun 12 2025 Valid 122000Z - 131200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTH-CENTRAL PLAINS... ...SUMMARY... Scattered areas of severe thunderstorm development are possible today into tonight, accompanied by potential for severe hail and wind across parts of the Great Plains, the Upper Midwest, the Texas coastal plain into the Lower Mississippi Valley, as well as a portion of the northern Mid-Atlantic. ...20z Update... The primary change for this update is to remove risk probabilities across parts of eastern TX and western LA in the wake of a gradually strengthening convective band/MCS where conditions have stabilized. Low-end risk probabilities have been expanded slightly across south TX to account for the southeastward propagation of a convective cluster developing on the outflow of the prior MCS. Recent RAP mesoanalysis estimates/forecast soundings suggest the downstream convective environment may be supportive of organized convection through early evening. Elsewhere, the forecast largely remains on track with few adjustments required. Convection developing within the upslope flow regime across the central High Plains should increase in coverage and intensity as ascent associated with a weak mid-level perturbation (currently over northern UT) overspreads the region. Across the Northern Mid-Atlantic/Northeast, temperatures have warmed into the mid-80s, which should minimize inhibition based on forecast soundings; however, satellite imagery continues to show meager vertical development of cumulus along the frontal zone, which limits confidence in convective initiation and the overall severe threat. See the previous discussion (below) and MCD #1260 for additional details. ..Moore.. 06/12/2025 .PREV DISCUSSION... /ISSUED 1151 AM CDT Thu Jun 12 2025/ ...North-central Plains including Nebraska/South Dakota... A low-amplitude shortwave trough and associated speed max will progress eastward over the northern High Plains, from southeast Montana/northeast Wyoming toward the Dakotas. Related forcing for ascent and a moderate belt of mid-level westerlies will overlie a wavy frontal zone across southern South Dakota and western Nebraska. At least widely scattered thunderstorms are expected into mid/late afternoon, with moderate buoyancy and 35-45 kt effective shear (especially northern Nebraska northward) supportive of supercells. Large hail and severe-caliber wind gusts are the primary hazards. ...South/East Texas to Lower Mississippi Valley/Mid-South... An extensive MCS and prominent outflow remain primary forecast factors today, with outflow now having progressed off the middle/upper Texas coast. An enhanced low/mid-level wind field on the eastern periphery of the convectively augmented upper low will continue to contribute to some supercell/tornado risk within a moist environment, although cloud cover and thermodynamic limitations may persist. Damaging winds may also occur on a sporadic/relatively limited basis regionally. ...Southeast/southern Appalachians... Strong heating is expected today across parts of Georgia into the Carolinas, where temperatures in the upper 80s F and dewpoints near 70F are forecast. This will lead to widespread moderate CAPE values and the development of scattered afternoon thunderstorms. Vertical shear is weak, but a few weakly organized thunderstorm clusters may reach severe intensity with gusty/damaging winds. ...Northern Mid-Atlantic/Northeast... With full insolation, moderate destabilization will steadily develop this afternoon near/south of a southward-moving front. While ingredients are severe-storm supportive, the extent of deep convective development may be limited by modest overall forcing/low-level convergence, but at least isolated damaging winds/hail will be possible where storms do develop. Favorable deep-layer shear (40+ kt effective) is conditionally supportive of well-organized storms including supercells. In a relative sense, severe storm development currently appears most probable across eastern Pennsylvania, northern New Jersey, and potentially toward the Great NYC Metro vicinity/far southeast New York. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Thu Jun 12 2025 Valid 122000Z - 131200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTH-CENTRAL PLAINS... ...SUMMARY... Scattered areas of severe thunderstorm development are possible today into tonight, accompanied by potential for severe hail and wind across parts of the Great Plains, the Upper Midwest, the Texas coastal plain into the Lower Mississippi Valley, as well as a portion of the northern Mid-Atlantic. ...20z Update... The primary change for this update is to remove risk probabilities across parts of eastern TX and western LA in the wake of a gradually strengthening convective band/MCS where conditions have stabilized. Low-end risk probabilities have been expanded slightly across south TX to account for the southeastward propagation of a convective cluster developing on the outflow of the prior MCS. Recent RAP mesoanalysis estimates/forecast soundings suggest the downstream convective environment may be supportive of organized convection through early evening. Elsewhere, the forecast largely remains on track with few adjustments required. Convection developing within the upslope flow regime across the central High Plains should increase in coverage and intensity as ascent associated with a weak mid-level perturbation (currently over northern UT) overspreads the region. Across the Northern Mid-Atlantic/Northeast, temperatures have warmed into the mid-80s, which should minimize inhibition based on forecast soundings; however, satellite imagery continues to show meager vertical development of cumulus along the frontal zone, which limits confidence in convective initiation and the overall severe threat. See the previous discussion (below) and MCD #1260 for additional details. ..Moore.. 06/12/2025 .PREV DISCUSSION... /ISSUED 1151 AM CDT Thu Jun 12 2025/ ...North-central Plains including Nebraska/South Dakota... A low-amplitude shortwave trough and associated speed max will progress eastward over the northern High Plains, from southeast Montana/northeast Wyoming toward the Dakotas. Related forcing for ascent and a moderate belt of mid-level westerlies will overlie a wavy frontal zone across southern South Dakota and western Nebraska. At least widely scattered thunderstorms are expected into mid/late afternoon, with moderate buoyancy and 35-45 kt effective shear (especially northern Nebraska northward) supportive of supercells. Large hail and severe-caliber wind gusts are the primary hazards. ...South/East Texas to Lower Mississippi Valley/Mid-South... An extensive MCS and prominent outflow remain primary forecast factors today, with outflow now having progressed off the middle/upper Texas coast. An enhanced low/mid-level wind field on the eastern periphery of the convectively augmented upper low will continue to contribute to some supercell/tornado risk within a moist environment, although cloud cover and thermodynamic limitations may persist. Damaging winds may also occur on a sporadic/relatively limited basis regionally. ...Southeast/southern Appalachians... Strong heating is expected today across parts of Georgia into the Carolinas, where temperatures in the upper 80s F and dewpoints near 70F are forecast. This will lead to widespread moderate CAPE values and the development of scattered afternoon thunderstorms. Vertical shear is weak, but a few weakly organized thunderstorm clusters may reach severe intensity with gusty/damaging winds. ...Northern Mid-Atlantic/Northeast... With full insolation, moderate destabilization will steadily develop this afternoon near/south of a southward-moving front. While ingredients are severe-storm supportive, the extent of deep convective development may be limited by modest overall forcing/low-level convergence, but at least isolated damaging winds/hail will be possible where storms do develop. Favorable deep-layer shear (40+ kt effective) is conditionally supportive of well-organized storms including supercells. In a relative sense, severe storm development currently appears most probable across eastern Pennsylvania, northern New Jersey, and potentially toward the Great NYC Metro vicinity/far southeast New York. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Thu Jun 12 2025 Valid 122000Z - 131200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTH-CENTRAL PLAINS... ...SUMMARY... Scattered areas of severe thunderstorm development are possible today into tonight, accompanied by potential for severe hail and wind across parts of the Great Plains, the Upper Midwest, the Texas coastal plain into the Lower Mississippi Valley, as well as a portion of the northern Mid-Atlantic. ...20z Update... The primary change for this update is to remove risk probabilities across parts of eastern TX and western LA in the wake of a gradually strengthening convective band/MCS where conditions have stabilized. Low-end risk probabilities have been expanded slightly across south TX to account for the southeastward propagation of a convective cluster developing on the outflow of the prior MCS. Recent RAP mesoanalysis estimates/forecast soundings suggest the downstream convective environment may be supportive of organized convection through early evening. Elsewhere, the forecast largely remains on track with few adjustments required. Convection developing within the upslope flow regime across the central High Plains should increase in coverage and intensity as ascent associated with a weak mid-level perturbation (currently over northern UT) overspreads the region. Across the Northern Mid-Atlantic/Northeast, temperatures have warmed into the mid-80s, which should minimize inhibition based on forecast soundings; however, satellite imagery continues to show meager vertical development of cumulus along the frontal zone, which limits confidence in convective initiation and the overall severe threat. See the previous discussion (below) and MCD #1260 for additional details. ..Moore.. 06/12/2025 .PREV DISCUSSION... /ISSUED 1151 AM CDT Thu Jun 12 2025/ ...North-central Plains including Nebraska/South Dakota... A low-amplitude shortwave trough and associated speed max will progress eastward over the northern High Plains, from southeast Montana/northeast Wyoming toward the Dakotas. Related forcing for ascent and a moderate belt of mid-level westerlies will overlie a wavy frontal zone across southern South Dakota and western Nebraska. At least widely scattered thunderstorms are expected into mid/late afternoon, with moderate buoyancy and 35-45 kt effective shear (especially northern Nebraska northward) supportive of supercells. Large hail and severe-caliber wind gusts are the primary hazards. ...South/East Texas to Lower Mississippi Valley/Mid-South... An extensive MCS and prominent outflow remain primary forecast factors today, with outflow now having progressed off the middle/upper Texas coast. An enhanced low/mid-level wind field on the eastern periphery of the convectively augmented upper low will continue to contribute to some supercell/tornado risk within a moist environment, although cloud cover and thermodynamic limitations may persist. Damaging winds may also occur on a sporadic/relatively limited basis regionally. ...Southeast/southern Appalachians... Strong heating is expected today across parts of Georgia into the Carolinas, where temperatures in the upper 80s F and dewpoints near 70F are forecast. This will lead to widespread moderate CAPE values and the development of scattered afternoon thunderstorms. Vertical shear is weak, but a few weakly organized thunderstorm clusters may reach severe intensity with gusty/damaging winds. ...Northern Mid-Atlantic/Northeast... With full insolation, moderate destabilization will steadily develop this afternoon near/south of a southward-moving front. While ingredients are severe-storm supportive, the extent of deep convective development may be limited by modest overall forcing/low-level convergence, but at least isolated damaging winds/hail will be possible where storms do develop. Favorable deep-layer shear (40+ kt effective) is conditionally supportive of well-organized storms including supercells. In a relative sense, severe storm development currently appears most probable across eastern Pennsylvania, northern New Jersey, and potentially toward the Great NYC Metro vicinity/far southeast New York. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Thu Jun 12 2025 Valid 122000Z - 131200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTH-CENTRAL PLAINS... ...SUMMARY... Scattered areas of severe thunderstorm development are possible today into tonight, accompanied by potential for severe hail and wind across parts of the Great Plains, the Upper Midwest, the Texas coastal plain into the Lower Mississippi Valley, as well as a portion of the northern Mid-Atlantic. ...20z Update... The primary change for this update is to remove risk probabilities across parts of eastern TX and western LA in the wake of a gradually strengthening convective band/MCS where conditions have stabilized. Low-end risk probabilities have been expanded slightly across south TX to account for the southeastward propagation of a convective cluster developing on the outflow of the prior MCS. Recent RAP mesoanalysis estimates/forecast soundings suggest the downstream convective environment may be supportive of organized convection through early evening. Elsewhere, the forecast largely remains on track with few adjustments required. Convection developing within the upslope flow regime across the central High Plains should increase in coverage and intensity as ascent associated with a weak mid-level perturbation (currently over northern UT) overspreads the region. Across the Northern Mid-Atlantic/Northeast, temperatures have warmed into the mid-80s, which should minimize inhibition based on forecast soundings; however, satellite imagery continues to show meager vertical development of cumulus along the frontal zone, which limits confidence in convective initiation and the overall severe threat. See the previous discussion (below) and MCD #1260 for additional details. ..Moore.. 06/12/2025 .PREV DISCUSSION... /ISSUED 1151 AM CDT Thu Jun 12 2025/ ...North-central Plains including Nebraska/South Dakota... A low-amplitude shortwave trough and associated speed max will progress eastward over the northern High Plains, from southeast Montana/northeast Wyoming toward the Dakotas. Related forcing for ascent and a moderate belt of mid-level westerlies will overlie a wavy frontal zone across southern South Dakota and western Nebraska. At least widely scattered thunderstorms are expected into mid/late afternoon, with moderate buoyancy and 35-45 kt effective shear (especially northern Nebraska northward) supportive of supercells. Large hail and severe-caliber wind gusts are the primary hazards. ...South/East Texas to Lower Mississippi Valley/Mid-South... An extensive MCS and prominent outflow remain primary forecast factors today, with outflow now having progressed off the middle/upper Texas coast. An enhanced low/mid-level wind field on the eastern periphery of the convectively augmented upper low will continue to contribute to some supercell/tornado risk within a moist environment, although cloud cover and thermodynamic limitations may persist. Damaging winds may also occur on a sporadic/relatively limited basis regionally. ...Southeast/southern Appalachians... Strong heating is expected today across parts of Georgia into the Carolinas, where temperatures in the upper 80s F and dewpoints near 70F are forecast. This will lead to widespread moderate CAPE values and the development of scattered afternoon thunderstorms. Vertical shear is weak, but a few weakly organized thunderstorm clusters may reach severe intensity with gusty/damaging winds. ...Northern Mid-Atlantic/Northeast... With full insolation, moderate destabilization will steadily develop this afternoon near/south of a southward-moving front. While ingredients are severe-storm supportive, the extent of deep convective development may be limited by modest overall forcing/low-level convergence, but at least isolated damaging winds/hail will be possible where storms do develop. Favorable deep-layer shear (40+ kt effective) is conditionally supportive of well-organized storms including supercells. In a relative sense, severe storm development currently appears most probable across eastern Pennsylvania, northern New Jersey, and potentially toward the Great NYC Metro vicinity/far southeast New York. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Thu Jun 12 2025 Valid 122000Z - 131200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTH-CENTRAL PLAINS... ...SUMMARY... Scattered areas of severe thunderstorm development are possible today into tonight, accompanied by potential for severe hail and wind across parts of the Great Plains, the Upper Midwest, the Texas coastal plain into the Lower Mississippi Valley, as well as a portion of the northern Mid-Atlantic. ...20z Update... The primary change for this update is to remove risk probabilities across parts of eastern TX and western LA in the wake of a gradually strengthening convective band/MCS where conditions have stabilized. Low-end risk probabilities have been expanded slightly across south TX to account for the southeastward propagation of a convective cluster developing on the outflow of the prior MCS. Recent RAP mesoanalysis estimates/forecast soundings suggest the downstream convective environment may be supportive of organized convection through early evening. Elsewhere, the forecast largely remains on track with few adjustments required. Convection developing within the upslope flow regime across the central High Plains should increase in coverage and intensity as ascent associated with a weak mid-level perturbation (currently over northern UT) overspreads the region. Across the Northern Mid-Atlantic/Northeast, temperatures have warmed into the mid-80s, which should minimize inhibition based on forecast soundings; however, satellite imagery continues to show meager vertical development of cumulus along the frontal zone, which limits confidence in convective initiation and the overall severe threat. See the previous discussion (below) and MCD #1260 for additional details. ..Moore.. 06/12/2025 .PREV DISCUSSION... /ISSUED 1151 AM CDT Thu Jun 12 2025/ ...North-central Plains including Nebraska/South Dakota... A low-amplitude shortwave trough and associated speed max will progress eastward over the northern High Plains, from southeast Montana/northeast Wyoming toward the Dakotas. Related forcing for ascent and a moderate belt of mid-level westerlies will overlie a wavy frontal zone across southern South Dakota and western Nebraska. At least widely scattered thunderstorms are expected into mid/late afternoon, with moderate buoyancy and 35-45 kt effective shear (especially northern Nebraska northward) supportive of supercells. Large hail and severe-caliber wind gusts are the primary hazards. ...South/East Texas to Lower Mississippi Valley/Mid-South... An extensive MCS and prominent outflow remain primary forecast factors today, with outflow now having progressed off the middle/upper Texas coast. An enhanced low/mid-level wind field on the eastern periphery of the convectively augmented upper low will continue to contribute to some supercell/tornado risk within a moist environment, although cloud cover and thermodynamic limitations may persist. Damaging winds may also occur on a sporadic/relatively limited basis regionally. ...Southeast/southern Appalachians... Strong heating is expected today across parts of Georgia into the Carolinas, where temperatures in the upper 80s F and dewpoints near 70F are forecast. This will lead to widespread moderate CAPE values and the development of scattered afternoon thunderstorms. Vertical shear is weak, but a few weakly organized thunderstorm clusters may reach severe intensity with gusty/damaging winds. ...Northern Mid-Atlantic/Northeast... With full insolation, moderate destabilization will steadily develop this afternoon near/south of a southward-moving front. While ingredients are severe-storm supportive, the extent of deep convective development may be limited by modest overall forcing/low-level convergence, but at least isolated damaging winds/hail will be possible where storms do develop. Favorable deep-layer shear (40+ kt effective) is conditionally supportive of well-organized storms including supercells. In a relative sense, severe storm development currently appears most probable across eastern Pennsylvania, northern New Jersey, and potentially toward the Great NYC Metro vicinity/far southeast New York. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Thu Jun 12 2025 Valid 122000Z - 131200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTH-CENTRAL PLAINS... ...SUMMARY... Scattered areas of severe thunderstorm development are possible today into tonight, accompanied by potential for severe hail and wind across parts of the Great Plains, the Upper Midwest, the Texas coastal plain into the Lower Mississippi Valley, as well as a portion of the northern Mid-Atlantic. ...20z Update... The primary change for this update is to remove risk probabilities across parts of eastern TX and western LA in the wake of a gradually strengthening convective band/MCS where conditions have stabilized. Low-end risk probabilities have been expanded slightly across south TX to account for the southeastward propagation of a convective cluster developing on the outflow of the prior MCS. Recent RAP mesoanalysis estimates/forecast soundings suggest the downstream convective environment may be supportive of organized convection through early evening. Elsewhere, the forecast largely remains on track with few adjustments required. Convection developing within the upslope flow regime across the central High Plains should increase in coverage and intensity as ascent associated with a weak mid-level perturbation (currently over northern UT) overspreads the region. Across the Northern Mid-Atlantic/Northeast, temperatures have warmed into the mid-80s, which should minimize inhibition based on forecast soundings; however, satellite imagery continues to show meager vertical development of cumulus along the frontal zone, which limits confidence in convective initiation and the overall severe threat. See the previous discussion (below) and MCD #1260 for additional details. ..Moore.. 06/12/2025 .PREV DISCUSSION... /ISSUED 1151 AM CDT Thu Jun 12 2025/ ...North-central Plains including Nebraska/South Dakota... A low-amplitude shortwave trough and associated speed max will progress eastward over the northern High Plains, from southeast Montana/northeast Wyoming toward the Dakotas. Related forcing for ascent and a moderate belt of mid-level westerlies will overlie a wavy frontal zone across southern South Dakota and western Nebraska. At least widely scattered thunderstorms are expected into mid/late afternoon, with moderate buoyancy and 35-45 kt effective shear (especially northern Nebraska northward) supportive of supercells. Large hail and severe-caliber wind gusts are the primary hazards. ...South/East Texas to Lower Mississippi Valley/Mid-South... An extensive MCS and prominent outflow remain primary forecast factors today, with outflow now having progressed off the middle/upper Texas coast. An enhanced low/mid-level wind field on the eastern periphery of the convectively augmented upper low will continue to contribute to some supercell/tornado risk within a moist environment, although cloud cover and thermodynamic limitations may persist. Damaging winds may also occur on a sporadic/relatively limited basis regionally. ...Southeast/southern Appalachians... Strong heating is expected today across parts of Georgia into the Carolinas, where temperatures in the upper 80s F and dewpoints near 70F are forecast. This will lead to widespread moderate CAPE values and the development of scattered afternoon thunderstorms. Vertical shear is weak, but a few weakly organized thunderstorm clusters may reach severe intensity with gusty/damaging winds. ...Northern Mid-Atlantic/Northeast... With full insolation, moderate destabilization will steadily develop this afternoon near/south of a southward-moving front. While ingredients are severe-storm supportive, the extent of deep convective development may be limited by modest overall forcing/low-level convergence, but at least isolated damaging winds/hail will be possible where storms do develop. Favorable deep-layer shear (40+ kt effective) is conditionally supportive of well-organized storms including supercells. In a relative sense, severe storm development currently appears most probable across eastern Pennsylvania, northern New Jersey, and potentially toward the Great NYC Metro vicinity/far southeast New York. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Thu Jun 12 2025 Valid 122000Z - 131200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTH-CENTRAL PLAINS... ...SUMMARY... Scattered areas of severe thunderstorm development are possible today into tonight, accompanied by potential for severe hail and wind across parts of the Great Plains, the Upper Midwest, the Texas coastal plain into the Lower Mississippi Valley, as well as a portion of the northern Mid-Atlantic. ...20z Update... The primary change for this update is to remove risk probabilities across parts of eastern TX and western LA in the wake of a gradually strengthening convective band/MCS where conditions have stabilized. Low-end risk probabilities have been expanded slightly across south TX to account for the southeastward propagation of a convective cluster developing on the outflow of the prior MCS. Recent RAP mesoanalysis estimates/forecast soundings suggest the downstream convective environment may be supportive of organized convection through early evening. Elsewhere, the forecast largely remains on track with few adjustments required. Convection developing within the upslope flow regime across the central High Plains should increase in coverage and intensity as ascent associated with a weak mid-level perturbation (currently over northern UT) overspreads the region. Across the Northern Mid-Atlantic/Northeast, temperatures have warmed into the mid-80s, which should minimize inhibition based on forecast soundings; however, satellite imagery continues to show meager vertical development of cumulus along the frontal zone, which limits confidence in convective initiation and the overall severe threat. See the previous discussion (below) and MCD #1260 for additional details. ..Moore.. 06/12/2025 .PREV DISCUSSION... /ISSUED 1151 AM CDT Thu Jun 12 2025/ ...North-central Plains including Nebraska/South Dakota... A low-amplitude shortwave trough and associated speed max will progress eastward over the northern High Plains, from southeast Montana/northeast Wyoming toward the Dakotas. Related forcing for ascent and a moderate belt of mid-level westerlies will overlie a wavy frontal zone across southern South Dakota and western Nebraska. At least widely scattered thunderstorms are expected into mid/late afternoon, with moderate buoyancy and 35-45 kt effective shear (especially northern Nebraska northward) supportive of supercells. Large hail and severe-caliber wind gusts are the primary hazards. ...South/East Texas to Lower Mississippi Valley/Mid-South... An extensive MCS and prominent outflow remain primary forecast factors today, with outflow now having progressed off the middle/upper Texas coast. An enhanced low/mid-level wind field on the eastern periphery of the convectively augmented upper low will continue to contribute to some supercell/tornado risk within a moist environment, although cloud cover and thermodynamic limitations may persist. Damaging winds may also occur on a sporadic/relatively limited basis regionally. ...Southeast/southern Appalachians... Strong heating is expected today across parts of Georgia into the Carolinas, where temperatures in the upper 80s F and dewpoints near 70F are forecast. This will lead to widespread moderate CAPE values and the development of scattered afternoon thunderstorms. Vertical shear is weak, but a few weakly organized thunderstorm clusters may reach severe intensity with gusty/damaging winds. ...Northern Mid-Atlantic/Northeast... With full insolation, moderate destabilization will steadily develop this afternoon near/south of a southward-moving front. While ingredients are severe-storm supportive, the extent of deep convective development may be limited by modest overall forcing/low-level convergence, but at least isolated damaging winds/hail will be possible where storms do develop. Favorable deep-layer shear (40+ kt effective) is conditionally supportive of well-organized storms including supercells. In a relative sense, severe storm development currently appears most probable across eastern Pennsylvania, northern New Jersey, and potentially toward the Great NYC Metro vicinity/far southeast New York. Read more