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SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1109 AM CDT Thu May 01 2025 Valid 011630Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE LOWER MS VALLEY THROUGH THE TN AND OH VALLEYS INTO THE LOWER GREAT LAKES...AND FROM THE TX/OK PAHANDLES EASTWARD ACROSS OK AND NORTH AND CENTRAL TX.... ...SUMMARY... Lines and/or clusters of strong to severe thunderstorms are likely to impact parts of the Ohio Valley into lower Great Lakes, parts of the lower Mississippi Valley, and the southern Great Plains this afternoon through tonight. ...OH Valley... Morning water vapor imagery shows a progressive and large shortwave trough moving across parts of MO/IL. Forcing ahead of this trough will lead to scattered thunderstorm development over eastern IN and central KY, with storms spreading northeastward through the afternoon and early evening. Forecast soundings show deep and moderately strong southwest flow aloft. This coupled with sufficient CAPE will pose a threat of organized lines/clusters of storms capable of damaging wind gusts. Activity is expected to spread into western NY/PA during the early evening before weakening. ...Central TX... A weak surface boundary extends from west-central LA westward into central TX this morning. Strong heating and ample moisture along/south of the boundary will yield max CAPE values over 4000 J/kg by late afternoon. Most 12z CAM solutions indicate at least isolated intense convection forming in this corridor. Those storms that form will pose a risk of very large hail and damaging winds. Other intense storms may form off the high terrain of northern Mexico and build into parts of central TX this evening. ...TX Panhandle into OK... A combination of strong heating and upslope low-level winds into the Raton mesa will aid in the development of a cluster of thunderstorms over southeast CO this afternoon. This activity will track southeastward into a progressively more moist/unstable air mass over the TX panhandle and western OK, where a few more intense storms are expected. Cells and bowing structures will pose a risk of large hail and damaging winds. By late tonight, other storms are expected to form ahead of this complex, affecting parts of central OK with a risk of large hail. ..Hart/Wendt.. 05/01/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1109 AM CDT Thu May 01 2025 Valid 011630Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE LOWER MS VALLEY THROUGH THE TN AND OH VALLEYS INTO THE LOWER GREAT LAKES...AND FROM THE TX/OK PAHANDLES EASTWARD ACROSS OK AND NORTH AND CENTRAL TX.... ...SUMMARY... Lines and/or clusters of strong to severe thunderstorms are likely to impact parts of the Ohio Valley into lower Great Lakes, parts of the lower Mississippi Valley, and the southern Great Plains this afternoon through tonight. ...OH Valley... Morning water vapor imagery shows a progressive and large shortwave trough moving across parts of MO/IL. Forcing ahead of this trough will lead to scattered thunderstorm development over eastern IN and central KY, with storms spreading northeastward through the afternoon and early evening. Forecast soundings show deep and moderately strong southwest flow aloft. This coupled with sufficient CAPE will pose a threat of organized lines/clusters of storms capable of damaging wind gusts. Activity is expected to spread into western NY/PA during the early evening before weakening. ...Central TX... A weak surface boundary extends from west-central LA westward into central TX this morning. Strong heating and ample moisture along/south of the boundary will yield max CAPE values over 4000 J/kg by late afternoon. Most 12z CAM solutions indicate at least isolated intense convection forming in this corridor. Those storms that form will pose a risk of very large hail and damaging winds. Other intense storms may form off the high terrain of northern Mexico and build into parts of central TX this evening. ...TX Panhandle into OK... A combination of strong heating and upslope low-level winds into the Raton mesa will aid in the development of a cluster of thunderstorms over southeast CO this afternoon. This activity will track southeastward into a progressively more moist/unstable air mass over the TX panhandle and western OK, where a few more intense storms are expected. Cells and bowing structures will pose a risk of large hail and damaging winds. By late tonight, other storms are expected to form ahead of this complex, affecting parts of central OK with a risk of large hail. ..Hart/Wendt.. 05/01/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1109 AM CDT Thu May 01 2025 Valid 011630Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE LOWER MS VALLEY THROUGH THE TN AND OH VALLEYS INTO THE LOWER GREAT LAKES...AND FROM THE TX/OK PAHANDLES EASTWARD ACROSS OK AND NORTH AND CENTRAL TX.... ...SUMMARY... Lines and/or clusters of strong to severe thunderstorms are likely to impact parts of the Ohio Valley into lower Great Lakes, parts of the lower Mississippi Valley, and the southern Great Plains this afternoon through tonight. ...OH Valley... Morning water vapor imagery shows a progressive and large shortwave trough moving across parts of MO/IL. Forcing ahead of this trough will lead to scattered thunderstorm development over eastern IN and central KY, with storms spreading northeastward through the afternoon and early evening. Forecast soundings show deep and moderately strong southwest flow aloft. This coupled with sufficient CAPE will pose a threat of organized lines/clusters of storms capable of damaging wind gusts. Activity is expected to spread into western NY/PA during the early evening before weakening. ...Central TX... A weak surface boundary extends from west-central LA westward into central TX this morning. Strong heating and ample moisture along/south of the boundary will yield max CAPE values over 4000 J/kg by late afternoon. Most 12z CAM solutions indicate at least isolated intense convection forming in this corridor. Those storms that form will pose a risk of very large hail and damaging winds. Other intense storms may form off the high terrain of northern Mexico and build into parts of central TX this evening. ...TX Panhandle into OK... A combination of strong heating and upslope low-level winds into the Raton mesa will aid in the development of a cluster of thunderstorms over southeast CO this afternoon. This activity will track southeastward into a progressively more moist/unstable air mass over the TX panhandle and western OK, where a few more intense storms are expected. Cells and bowing structures will pose a risk of large hail and damaging winds. By late tonight, other storms are expected to form ahead of this complex, affecting parts of central OK with a risk of large hail. ..Hart/Wendt.. 05/01/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1109 AM CDT Thu May 01 2025 Valid 011630Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE LOWER MS VALLEY THROUGH THE TN AND OH VALLEYS INTO THE LOWER GREAT LAKES...AND FROM THE TX/OK PAHANDLES EASTWARD ACROSS OK AND NORTH AND CENTRAL TX.... ...SUMMARY... Lines and/or clusters of strong to severe thunderstorms are likely to impact parts of the Ohio Valley into lower Great Lakes, parts of the lower Mississippi Valley, and the southern Great Plains this afternoon through tonight. ...OH Valley... Morning water vapor imagery shows a progressive and large shortwave trough moving across parts of MO/IL. Forcing ahead of this trough will lead to scattered thunderstorm development over eastern IN and central KY, with storms spreading northeastward through the afternoon and early evening. Forecast soundings show deep and moderately strong southwest flow aloft. This coupled with sufficient CAPE will pose a threat of organized lines/clusters of storms capable of damaging wind gusts. Activity is expected to spread into western NY/PA during the early evening before weakening. ...Central TX... A weak surface boundary extends from west-central LA westward into central TX this morning. Strong heating and ample moisture along/south of the boundary will yield max CAPE values over 4000 J/kg by late afternoon. Most 12z CAM solutions indicate at least isolated intense convection forming in this corridor. Those storms that form will pose a risk of very large hail and damaging winds. Other intense storms may form off the high terrain of northern Mexico and build into parts of central TX this evening. ...TX Panhandle into OK... A combination of strong heating and upslope low-level winds into the Raton mesa will aid in the development of a cluster of thunderstorms over southeast CO this afternoon. This activity will track southeastward into a progressively more moist/unstable air mass over the TX panhandle and western OK, where a few more intense storms are expected. Cells and bowing structures will pose a risk of large hail and damaging winds. By late tonight, other storms are expected to form ahead of this complex, affecting parts of central OK with a risk of large hail. ..Hart/Wendt.. 05/01/2025 Read more

Level 5 water restrictions began in Danvers on May 1 due to the low flow of the Ipswich River and the low level of the reservoir. The Level 5 water restrictions limit outdoor water use to lawns and gardens using hand-held hoses and watering cans only from 7 p.m. to 8 a.m. Danvers, MA Patch, May 1, 2025

Texas’ dust season, which typically runs from March through May, has been unusually dusty, with ten full-fledged dust storms—during which visibility drops to just half of a mile—compared to the average of 1.8. Newsweek (New York), May 1, 2025

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0757 AM CDT Thu May 01 2025 Valid 011300Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE LOWER MS VALLEY THROUGH THE TN AND OH VALLEYS INTO THE LOWER GREAT LAKES...AND FROM THE TX/OK PANHANDLES EASTWARD ACROSS OK AND NORTH TX.... ...SUMMARY... Lines and/or clusters of strong to severe thunderstorms are likely to impact parts of the Ohio Valley into lower Great Lakes, parts of the lower Mississippi Valley, and the southern Great Plains this afternoon through tonight. ...Synopsis... Early morning satellite imagery shows several shortwave troughs across the CONUS, including one entering the Lower MO Valley/Ozarks vicinity, another moving into NE, and another off the southern CA coast. The lead wave is forecast to progress quickly northeastward through the OH Valley and Great Lakes while losing amplitude under the increasingly confluent flow aloft. At the same time, another shortwave trough will drop southeastward through the northern High Plains into the northern/central Plains, leading to some amplification of the upper troughing across the north-central CONUS. Recent surface analysis revealed several lows within a broad area of low pressure across the central CONUS, one over west-central IL, another near the SD/ND/MN border intersection, and a third over north-central OK. A warm front extends eastward from the low over west-central IL, while modest troughing extends between the Upper Midwest low and the one over north-central OK. The west-central IL low is expected to deepen throughout the day as it moves northeastward ahead of its parent shortwave, with the attendant warm front advancing northward as well. The northernmost surface low is expected to progress slowly eastward as well, with its associated surface troughing also drifting eastward. A more stationary pattern is anticipated in the vicinity of the OK low throughout much of the period. ...TN/OH Valleys into the Lower Great Lakes... Low 60s dewpoints are already in place across the Lower OH and TN Valley this morning. Continued northward/northeastward advection of this low-level moisture is anticipated today as the surface low progresses northeastward. This increased moisture coupled with modest heating will help support moderate buoyancy across much of the region by early afternoon. Broad large-scale ascent and surface troughing are expected over the region amid this destabilization, which is forecast to result in widespread thunderstorms during the afternoon and evening. The convective mode will likely be dominated by linear structures, with one or more convective lines possible. Primary severe risk will be damaging gusts, supported by moderate southwesterly flow in the lower troposphere. Some hail is also possible, particularly during cell mergers. The tornado risk will be low but non-zero, as veered low-level flow limits the low-level shear. ...Lower MS Valley... The airmass across the region is expected to quickly destabilize as low-level moisture advects back into the region in the wake of the convection currently moving through. Upper 60s dewpoints coupled with modest heating will result in moderate to strong buoyancy and no convective inhibition by the early afternoon. Even modest low-level convergence should be enough to initiate deep convection, but any remnant outflow could also act as a focus for convective initiation. Robust updrafts are expected with initial development, with a quick trend towards outflow-dominant structures. Large hail and damaging gusts are the primary risks. ...TX/OK Panhandles into much of OK and north TX... Low-level moisture is expected to advect back northwestward into the TX Panhandle throughout the day. Cold mid-level temperatures are already in place (-16 deg C at 500 on the 12Z AMA sounding), so this added low-level moisture coupled with glancing ascent will likely result in late evening thunderstorm development. Most of the convection-allowing guidance is suggesting these storms will grow upscale quickly into an MCS, with some of guidance suggesting it could be quite and capable of producing significant wind gusts as it moves eastward across the TX Panhandle and into OK. Additionally, gradual increase in the low-level moisture beneath cold mid-level temperatures and associated steep mid-level lapse rates will result in strong buoyancy across southern OK. Modest warm-air advection could result in convective initiation across this region amid an environment that supports very large hail. Complex interaction is possible between the potential MCS and the more cellular development ahead of it, but some severe threat appears possible through early tomorrow morning. ..Mosier/Jewell.. 05/01/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0757 AM CDT Thu May 01 2025 Valid 011300Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE LOWER MS VALLEY THROUGH THE TN AND OH VALLEYS INTO THE LOWER GREAT LAKES...AND FROM THE TX/OK PANHANDLES EASTWARD ACROSS OK AND NORTH TX.... ...SUMMARY... Lines and/or clusters of strong to severe thunderstorms are likely to impact parts of the Ohio Valley into lower Great Lakes, parts of the lower Mississippi Valley, and the southern Great Plains this afternoon through tonight. ...Synopsis... Early morning satellite imagery shows several shortwave troughs across the CONUS, including one entering the Lower MO Valley/Ozarks vicinity, another moving into NE, and another off the southern CA coast. The lead wave is forecast to progress quickly northeastward through the OH Valley and Great Lakes while losing amplitude under the increasingly confluent flow aloft. At the same time, another shortwave trough will drop southeastward through the northern High Plains into the northern/central Plains, leading to some amplification of the upper troughing across the north-central CONUS. Recent surface analysis revealed several lows within a broad area of low pressure across the central CONUS, one over west-central IL, another near the SD/ND/MN border intersection, and a third over north-central OK. A warm front extends eastward from the low over west-central IL, while modest troughing extends between the Upper Midwest low and the one over north-central OK. The west-central IL low is expected to deepen throughout the day as it moves northeastward ahead of its parent shortwave, with the attendant warm front advancing northward as well. The northernmost surface low is expected to progress slowly eastward as well, with its associated surface troughing also drifting eastward. A more stationary pattern is anticipated in the vicinity of the OK low throughout much of the period. ...TN/OH Valleys into the Lower Great Lakes... Low 60s dewpoints are already in place across the Lower OH and TN Valley this morning. Continued northward/northeastward advection of this low-level moisture is anticipated today as the surface low progresses northeastward. This increased moisture coupled with modest heating will help support moderate buoyancy across much of the region by early afternoon. Broad large-scale ascent and surface troughing are expected over the region amid this destabilization, which is forecast to result in widespread thunderstorms during the afternoon and evening. The convective mode will likely be dominated by linear structures, with one or more convective lines possible. Primary severe risk will be damaging gusts, supported by moderate southwesterly flow in the lower troposphere. Some hail is also possible, particularly during cell mergers. The tornado risk will be low but non-zero, as veered low-level flow limits the low-level shear. ...Lower MS Valley... The airmass across the region is expected to quickly destabilize as low-level moisture advects back into the region in the wake of the convection currently moving through. Upper 60s dewpoints coupled with modest heating will result in moderate to strong buoyancy and no convective inhibition by the early afternoon. Even modest low-level convergence should be enough to initiate deep convection, but any remnant outflow could also act as a focus for convective initiation. Robust updrafts are expected with initial development, with a quick trend towards outflow-dominant structures. Large hail and damaging gusts are the primary risks. ...TX/OK Panhandles into much of OK and north TX... Low-level moisture is expected to advect back northwestward into the TX Panhandle throughout the day. Cold mid-level temperatures are already in place (-16 deg C at 500 on the 12Z AMA sounding), so this added low-level moisture coupled with glancing ascent will likely result in late evening thunderstorm development. Most of the convection-allowing guidance is suggesting these storms will grow upscale quickly into an MCS, with some of guidance suggesting it could be quite and capable of producing significant wind gusts as it moves eastward across the TX Panhandle and into OK. Additionally, gradual increase in the low-level moisture beneath cold mid-level temperatures and associated steep mid-level lapse rates will result in strong buoyancy across southern OK. Modest warm-air advection could result in convective initiation across this region amid an environment that supports very large hail. Complex interaction is possible between the potential MCS and the more cellular development ahead of it, but some severe threat appears possible through early tomorrow morning. ..Mosier/Jewell.. 05/01/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0757 AM CDT Thu May 01 2025 Valid 011300Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE LOWER MS VALLEY THROUGH THE TN AND OH VALLEYS INTO THE LOWER GREAT LAKES...AND FROM THE TX/OK PANHANDLES EASTWARD ACROSS OK AND NORTH TX.... ...SUMMARY... Lines and/or clusters of strong to severe thunderstorms are likely to impact parts of the Ohio Valley into lower Great Lakes, parts of the lower Mississippi Valley, and the southern Great Plains this afternoon through tonight. ...Synopsis... Early morning satellite imagery shows several shortwave troughs across the CONUS, including one entering the Lower MO Valley/Ozarks vicinity, another moving into NE, and another off the southern CA coast. The lead wave is forecast to progress quickly northeastward through the OH Valley and Great Lakes while losing amplitude under the increasingly confluent flow aloft. At the same time, another shortwave trough will drop southeastward through the northern High Plains into the northern/central Plains, leading to some amplification of the upper troughing across the north-central CONUS. Recent surface analysis revealed several lows within a broad area of low pressure across the central CONUS, one over west-central IL, another near the SD/ND/MN border intersection, and a third over north-central OK. A warm front extends eastward from the low over west-central IL, while modest troughing extends between the Upper Midwest low and the one over north-central OK. The west-central IL low is expected to deepen throughout the day as it moves northeastward ahead of its parent shortwave, with the attendant warm front advancing northward as well. The northernmost surface low is expected to progress slowly eastward as well, with its associated surface troughing also drifting eastward. A more stationary pattern is anticipated in the vicinity of the OK low throughout much of the period. ...TN/OH Valleys into the Lower Great Lakes... Low 60s dewpoints are already in place across the Lower OH and TN Valley this morning. Continued northward/northeastward advection of this low-level moisture is anticipated today as the surface low progresses northeastward. This increased moisture coupled with modest heating will help support moderate buoyancy across much of the region by early afternoon. Broad large-scale ascent and surface troughing are expected over the region amid this destabilization, which is forecast to result in widespread thunderstorms during the afternoon and evening. The convective mode will likely be dominated by linear structures, with one or more convective lines possible. Primary severe risk will be damaging gusts, supported by moderate southwesterly flow in the lower troposphere. Some hail is also possible, particularly during cell mergers. The tornado risk will be low but non-zero, as veered low-level flow limits the low-level shear. ...Lower MS Valley... The airmass across the region is expected to quickly destabilize as low-level moisture advects back into the region in the wake of the convection currently moving through. Upper 60s dewpoints coupled with modest heating will result in moderate to strong buoyancy and no convective inhibition by the early afternoon. Even modest low-level convergence should be enough to initiate deep convection, but any remnant outflow could also act as a focus for convective initiation. Robust updrafts are expected with initial development, with a quick trend towards outflow-dominant structures. Large hail and damaging gusts are the primary risks. ...TX/OK Panhandles into much of OK and north TX... Low-level moisture is expected to advect back northwestward into the TX Panhandle throughout the day. Cold mid-level temperatures are already in place (-16 deg C at 500 on the 12Z AMA sounding), so this added low-level moisture coupled with glancing ascent will likely result in late evening thunderstorm development. Most of the convection-allowing guidance is suggesting these storms will grow upscale quickly into an MCS, with some of guidance suggesting it could be quite and capable of producing significant wind gusts as it moves eastward across the TX Panhandle and into OK. Additionally, gradual increase in the low-level moisture beneath cold mid-level temperatures and associated steep mid-level lapse rates will result in strong buoyancy across southern OK. Modest warm-air advection could result in convective initiation across this region amid an environment that supports very large hail. Complex interaction is possible between the potential MCS and the more cellular development ahead of it, but some severe threat appears possible through early tomorrow morning. ..Mosier/Jewell.. 05/01/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0757 AM CDT Thu May 01 2025 Valid 011300Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE LOWER MS VALLEY THROUGH THE TN AND OH VALLEYS INTO THE LOWER GREAT LAKES...AND FROM THE TX/OK PANHANDLES EASTWARD ACROSS OK AND NORTH TX.... ...SUMMARY... Lines and/or clusters of strong to severe thunderstorms are likely to impact parts of the Ohio Valley into lower Great Lakes, parts of the lower Mississippi Valley, and the southern Great Plains this afternoon through tonight. ...Synopsis... Early morning satellite imagery shows several shortwave troughs across the CONUS, including one entering the Lower MO Valley/Ozarks vicinity, another moving into NE, and another off the southern CA coast. The lead wave is forecast to progress quickly northeastward through the OH Valley and Great Lakes while losing amplitude under the increasingly confluent flow aloft. At the same time, another shortwave trough will drop southeastward through the northern High Plains into the northern/central Plains, leading to some amplification of the upper troughing across the north-central CONUS. Recent surface analysis revealed several lows within a broad area of low pressure across the central CONUS, one over west-central IL, another near the SD/ND/MN border intersection, and a third over north-central OK. A warm front extends eastward from the low over west-central IL, while modest troughing extends between the Upper Midwest low and the one over north-central OK. The west-central IL low is expected to deepen throughout the day as it moves northeastward ahead of its parent shortwave, with the attendant warm front advancing northward as well. The northernmost surface low is expected to progress slowly eastward as well, with its associated surface troughing also drifting eastward. A more stationary pattern is anticipated in the vicinity of the OK low throughout much of the period. ...TN/OH Valleys into the Lower Great Lakes... Low 60s dewpoints are already in place across the Lower OH and TN Valley this morning. Continued northward/northeastward advection of this low-level moisture is anticipated today as the surface low progresses northeastward. This increased moisture coupled with modest heating will help support moderate buoyancy across much of the region by early afternoon. Broad large-scale ascent and surface troughing are expected over the region amid this destabilization, which is forecast to result in widespread thunderstorms during the afternoon and evening. The convective mode will likely be dominated by linear structures, with one or more convective lines possible. Primary severe risk will be damaging gusts, supported by moderate southwesterly flow in the lower troposphere. Some hail is also possible, particularly during cell mergers. The tornado risk will be low but non-zero, as veered low-level flow limits the low-level shear. ...Lower MS Valley... The airmass across the region is expected to quickly destabilize as low-level moisture advects back into the region in the wake of the convection currently moving through. Upper 60s dewpoints coupled with modest heating will result in moderate to strong buoyancy and no convective inhibition by the early afternoon. Even modest low-level convergence should be enough to initiate deep convection, but any remnant outflow could also act as a focus for convective initiation. Robust updrafts are expected with initial development, with a quick trend towards outflow-dominant structures. Large hail and damaging gusts are the primary risks. ...TX/OK Panhandles into much of OK and north TX... Low-level moisture is expected to advect back northwestward into the TX Panhandle throughout the day. Cold mid-level temperatures are already in place (-16 deg C at 500 on the 12Z AMA sounding), so this added low-level moisture coupled with glancing ascent will likely result in late evening thunderstorm development. Most of the convection-allowing guidance is suggesting these storms will grow upscale quickly into an MCS, with some of guidance suggesting it could be quite and capable of producing significant wind gusts as it moves eastward across the TX Panhandle and into OK. Additionally, gradual increase in the low-level moisture beneath cold mid-level temperatures and associated steep mid-level lapse rates will result in strong buoyancy across southern OK. Modest warm-air advection could result in convective initiation across this region amid an environment that supports very large hail. Complex interaction is possible between the potential MCS and the more cellular development ahead of it, but some severe threat appears possible through early tomorrow morning. ..Mosier/Jewell.. 05/01/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0757 AM CDT Thu May 01 2025 Valid 011300Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE LOWER MS VALLEY THROUGH THE TN AND OH VALLEYS INTO THE LOWER GREAT LAKES...AND FROM THE TX/OK PANHANDLES EASTWARD ACROSS OK AND NORTH TX.... ...SUMMARY... Lines and/or clusters of strong to severe thunderstorms are likely to impact parts of the Ohio Valley into lower Great Lakes, parts of the lower Mississippi Valley, and the southern Great Plains this afternoon through tonight. ...Synopsis... Early morning satellite imagery shows several shortwave troughs across the CONUS, including one entering the Lower MO Valley/Ozarks vicinity, another moving into NE, and another off the southern CA coast. The lead wave is forecast to progress quickly northeastward through the OH Valley and Great Lakes while losing amplitude under the increasingly confluent flow aloft. At the same time, another shortwave trough will drop southeastward through the northern High Plains into the northern/central Plains, leading to some amplification of the upper troughing across the north-central CONUS. Recent surface analysis revealed several lows within a broad area of low pressure across the central CONUS, one over west-central IL, another near the SD/ND/MN border intersection, and a third over north-central OK. A warm front extends eastward from the low over west-central IL, while modest troughing extends between the Upper Midwest low and the one over north-central OK. The west-central IL low is expected to deepen throughout the day as it moves northeastward ahead of its parent shortwave, with the attendant warm front advancing northward as well. The northernmost surface low is expected to progress slowly eastward as well, with its associated surface troughing also drifting eastward. A more stationary pattern is anticipated in the vicinity of the OK low throughout much of the period. ...TN/OH Valleys into the Lower Great Lakes... Low 60s dewpoints are already in place across the Lower OH and TN Valley this morning. Continued northward/northeastward advection of this low-level moisture is anticipated today as the surface low progresses northeastward. This increased moisture coupled with modest heating will help support moderate buoyancy across much of the region by early afternoon. Broad large-scale ascent and surface troughing are expected over the region amid this destabilization, which is forecast to result in widespread thunderstorms during the afternoon and evening. The convective mode will likely be dominated by linear structures, with one or more convective lines possible. Primary severe risk will be damaging gusts, supported by moderate southwesterly flow in the lower troposphere. Some hail is also possible, particularly during cell mergers. The tornado risk will be low but non-zero, as veered low-level flow limits the low-level shear. ...Lower MS Valley... The airmass across the region is expected to quickly destabilize as low-level moisture advects back into the region in the wake of the convection currently moving through. Upper 60s dewpoints coupled with modest heating will result in moderate to strong buoyancy and no convective inhibition by the early afternoon. Even modest low-level convergence should be enough to initiate deep convection, but any remnant outflow could also act as a focus for convective initiation. Robust updrafts are expected with initial development, with a quick trend towards outflow-dominant structures. Large hail and damaging gusts are the primary risks. ...TX/OK Panhandles into much of OK and north TX... Low-level moisture is expected to advect back northwestward into the TX Panhandle throughout the day. Cold mid-level temperatures are already in place (-16 deg C at 500 on the 12Z AMA sounding), so this added low-level moisture coupled with glancing ascent will likely result in late evening thunderstorm development. Most of the convection-allowing guidance is suggesting these storms will grow upscale quickly into an MCS, with some of guidance suggesting it could be quite and capable of producing significant wind gusts as it moves eastward across the TX Panhandle and into OK. Additionally, gradual increase in the low-level moisture beneath cold mid-level temperatures and associated steep mid-level lapse rates will result in strong buoyancy across southern OK. Modest warm-air advection could result in convective initiation across this region amid an environment that supports very large hail. Complex interaction is possible between the potential MCS and the more cellular development ahead of it, but some severe threat appears possible through early tomorrow morning. ..Mosier/Jewell.. 05/01/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0757 AM CDT Thu May 01 2025 Valid 011300Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE LOWER MS VALLEY THROUGH THE TN AND OH VALLEYS INTO THE LOWER GREAT LAKES...AND FROM THE TX/OK PANHANDLES EASTWARD ACROSS OK AND NORTH TX.... ...SUMMARY... Lines and/or clusters of strong to severe thunderstorms are likely to impact parts of the Ohio Valley into lower Great Lakes, parts of the lower Mississippi Valley, and the southern Great Plains this afternoon through tonight. ...Synopsis... Early morning satellite imagery shows several shortwave troughs across the CONUS, including one entering the Lower MO Valley/Ozarks vicinity, another moving into NE, and another off the southern CA coast. The lead wave is forecast to progress quickly northeastward through the OH Valley and Great Lakes while losing amplitude under the increasingly confluent flow aloft. At the same time, another shortwave trough will drop southeastward through the northern High Plains into the northern/central Plains, leading to some amplification of the upper troughing across the north-central CONUS. Recent surface analysis revealed several lows within a broad area of low pressure across the central CONUS, one over west-central IL, another near the SD/ND/MN border intersection, and a third over north-central OK. A warm front extends eastward from the low over west-central IL, while modest troughing extends between the Upper Midwest low and the one over north-central OK. The west-central IL low is expected to deepen throughout the day as it moves northeastward ahead of its parent shortwave, with the attendant warm front advancing northward as well. The northernmost surface low is expected to progress slowly eastward as well, with its associated surface troughing also drifting eastward. A more stationary pattern is anticipated in the vicinity of the OK low throughout much of the period. ...TN/OH Valleys into the Lower Great Lakes... Low 60s dewpoints are already in place across the Lower OH and TN Valley this morning. Continued northward/northeastward advection of this low-level moisture is anticipated today as the surface low progresses northeastward. This increased moisture coupled with modest heating will help support moderate buoyancy across much of the region by early afternoon. Broad large-scale ascent and surface troughing are expected over the region amid this destabilization, which is forecast to result in widespread thunderstorms during the afternoon and evening. The convective mode will likely be dominated by linear structures, with one or more convective lines possible. Primary severe risk will be damaging gusts, supported by moderate southwesterly flow in the lower troposphere. Some hail is also possible, particularly during cell mergers. The tornado risk will be low but non-zero, as veered low-level flow limits the low-level shear. ...Lower MS Valley... The airmass across the region is expected to quickly destabilize as low-level moisture advects back into the region in the wake of the convection currently moving through. Upper 60s dewpoints coupled with modest heating will result in moderate to strong buoyancy and no convective inhibition by the early afternoon. Even modest low-level convergence should be enough to initiate deep convection, but any remnant outflow could also act as a focus for convective initiation. Robust updrafts are expected with initial development, with a quick trend towards outflow-dominant structures. Large hail and damaging gusts are the primary risks. ...TX/OK Panhandles into much of OK and north TX... Low-level moisture is expected to advect back northwestward into the TX Panhandle throughout the day. Cold mid-level temperatures are already in place (-16 deg C at 500 on the 12Z AMA sounding), so this added low-level moisture coupled with glancing ascent will likely result in late evening thunderstorm development. Most of the convection-allowing guidance is suggesting these storms will grow upscale quickly into an MCS, with some of guidance suggesting it could be quite and capable of producing significant wind gusts as it moves eastward across the TX Panhandle and into OK. Additionally, gradual increase in the low-level moisture beneath cold mid-level temperatures and associated steep mid-level lapse rates will result in strong buoyancy across southern OK. Modest warm-air advection could result in convective initiation across this region amid an environment that supports very large hail. Complex interaction is possible between the potential MCS and the more cellular development ahead of it, but some severe threat appears possible through early tomorrow morning. ..Mosier/Jewell.. 05/01/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0757 AM CDT Thu May 01 2025 Valid 011300Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE LOWER MS VALLEY THROUGH THE TN AND OH VALLEYS INTO THE LOWER GREAT LAKES...AND FROM THE TX/OK PANHANDLES EASTWARD ACROSS OK AND NORTH TX.... ...SUMMARY... Lines and/or clusters of strong to severe thunderstorms are likely to impact parts of the Ohio Valley into lower Great Lakes, parts of the lower Mississippi Valley, and the southern Great Plains this afternoon through tonight. ...Synopsis... Early morning satellite imagery shows several shortwave troughs across the CONUS, including one entering the Lower MO Valley/Ozarks vicinity, another moving into NE, and another off the southern CA coast. The lead wave is forecast to progress quickly northeastward through the OH Valley and Great Lakes while losing amplitude under the increasingly confluent flow aloft. At the same time, another shortwave trough will drop southeastward through the northern High Plains into the northern/central Plains, leading to some amplification of the upper troughing across the north-central CONUS. Recent surface analysis revealed several lows within a broad area of low pressure across the central CONUS, one over west-central IL, another near the SD/ND/MN border intersection, and a third over north-central OK. A warm front extends eastward from the low over west-central IL, while modest troughing extends between the Upper Midwest low and the one over north-central OK. The west-central IL low is expected to deepen throughout the day as it moves northeastward ahead of its parent shortwave, with the attendant warm front advancing northward as well. The northernmost surface low is expected to progress slowly eastward as well, with its associated surface troughing also drifting eastward. A more stationary pattern is anticipated in the vicinity of the OK low throughout much of the period. ...TN/OH Valleys into the Lower Great Lakes... Low 60s dewpoints are already in place across the Lower OH and TN Valley this morning. Continued northward/northeastward advection of this low-level moisture is anticipated today as the surface low progresses northeastward. This increased moisture coupled with modest heating will help support moderate buoyancy across much of the region by early afternoon. Broad large-scale ascent and surface troughing are expected over the region amid this destabilization, which is forecast to result in widespread thunderstorms during the afternoon and evening. The convective mode will likely be dominated by linear structures, with one or more convective lines possible. Primary severe risk will be damaging gusts, supported by moderate southwesterly flow in the lower troposphere. Some hail is also possible, particularly during cell mergers. The tornado risk will be low but non-zero, as veered low-level flow limits the low-level shear. ...Lower MS Valley... The airmass across the region is expected to quickly destabilize as low-level moisture advects back into the region in the wake of the convection currently moving through. Upper 60s dewpoints coupled with modest heating will result in moderate to strong buoyancy and no convective inhibition by the early afternoon. Even modest low-level convergence should be enough to initiate deep convection, but any remnant outflow could also act as a focus for convective initiation. Robust updrafts are expected with initial development, with a quick trend towards outflow-dominant structures. Large hail and damaging gusts are the primary risks. ...TX/OK Panhandles into much of OK and north TX... Low-level moisture is expected to advect back northwestward into the TX Panhandle throughout the day. Cold mid-level temperatures are already in place (-16 deg C at 500 on the 12Z AMA sounding), so this added low-level moisture coupled with glancing ascent will likely result in late evening thunderstorm development. Most of the convection-allowing guidance is suggesting these storms will grow upscale quickly into an MCS, with some of guidance suggesting it could be quite and capable of producing significant wind gusts as it moves eastward across the TX Panhandle and into OK. Additionally, gradual increase in the low-level moisture beneath cold mid-level temperatures and associated steep mid-level lapse rates will result in strong buoyancy across southern OK. Modest warm-air advection could result in convective initiation across this region amid an environment that supports very large hail. Complex interaction is possible between the potential MCS and the more cellular development ahead of it, but some severe threat appears possible through early tomorrow morning. ..Mosier/Jewell.. 05/01/2025 Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0355 AM CDT Thu May 01 2025 Valid 041200Z - 091200Z ...DISCUSSION... High pressure will dominate much of the eastern CONUS at the start of the extended period. This will shift most moisture into the Atlantic/Gulf of America. The only exception will be across Texas where east-southeasterly flow will advect richer low-level moisture into the southern High Plains. This will be the focus for any potential severe storms on Day 4/Sun and Day 5/Mon. However, specific during this period, and particularly beyond, are quite nebulous. The ECMWF cuts off an upper low across the Ohio Valley vicinity on Saturday Night while the GFS waits to cut off the upper-low across the Southeast US on Monday/Tuesday. Farther west there is more consistency in the upper pattern with a cutoff low in the Southwest vicinity. Enhanced southwesterly flow could result in several days of severe weather in the southern Plains. However, moisture remains uncertain due to aforementioned timing/location differences for the mid-level trough in the East. The GFS solution results in a more progressive cold front which clears out most of the greater moisture from the Gulf. However, the ECMWF stalls the front across the central Gulf which leaves a reservoir of rich theta-e which can be advected across Texas and vicinity during the early-mid part of next week. Therefore, predictability remains too low for probabilities at this time, but once the upper-level pattern becomes more clear, probabilities may be necessary. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0355 AM CDT Thu May 01 2025 Valid 041200Z - 091200Z ...DISCUSSION... High pressure will dominate much of the eastern CONUS at the start of the extended period. This will shift most moisture into the Atlantic/Gulf of America. The only exception will be across Texas where east-southeasterly flow will advect richer low-level moisture into the southern High Plains. This will be the focus for any potential severe storms on Day 4/Sun and Day 5/Mon. However, specific during this period, and particularly beyond, are quite nebulous. The ECMWF cuts off an upper low across the Ohio Valley vicinity on Saturday Night while the GFS waits to cut off the upper-low across the Southeast US on Monday/Tuesday. Farther west there is more consistency in the upper pattern with a cutoff low in the Southwest vicinity. Enhanced southwesterly flow could result in several days of severe weather in the southern Plains. However, moisture remains uncertain due to aforementioned timing/location differences for the mid-level trough in the East. The GFS solution results in a more progressive cold front which clears out most of the greater moisture from the Gulf. However, the ECMWF stalls the front across the central Gulf which leaves a reservoir of rich theta-e which can be advected across Texas and vicinity during the early-mid part of next week. Therefore, predictability remains too low for probabilities at this time, but once the upper-level pattern becomes more clear, probabilities may be necessary. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0355 AM CDT Thu May 01 2025 Valid 041200Z - 091200Z ...DISCUSSION... High pressure will dominate much of the eastern CONUS at the start of the extended period. This will shift most moisture into the Atlantic/Gulf of America. The only exception will be across Texas where east-southeasterly flow will advect richer low-level moisture into the southern High Plains. This will be the focus for any potential severe storms on Day 4/Sun and Day 5/Mon. However, specific during this period, and particularly beyond, are quite nebulous. The ECMWF cuts off an upper low across the Ohio Valley vicinity on Saturday Night while the GFS waits to cut off the upper-low across the Southeast US on Monday/Tuesday. Farther west there is more consistency in the upper pattern with a cutoff low in the Southwest vicinity. Enhanced southwesterly flow could result in several days of severe weather in the southern Plains. However, moisture remains uncertain due to aforementioned timing/location differences for the mid-level trough in the East. The GFS solution results in a more progressive cold front which clears out most of the greater moisture from the Gulf. However, the ECMWF stalls the front across the central Gulf which leaves a reservoir of rich theta-e which can be advected across Texas and vicinity during the early-mid part of next week. Therefore, predictability remains too low for probabilities at this time, but once the upper-level pattern becomes more clear, probabilities may be necessary. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0355 AM CDT Thu May 01 2025 Valid 041200Z - 091200Z ...DISCUSSION... High pressure will dominate much of the eastern CONUS at the start of the extended period. This will shift most moisture into the Atlantic/Gulf of America. The only exception will be across Texas where east-southeasterly flow will advect richer low-level moisture into the southern High Plains. This will be the focus for any potential severe storms on Day 4/Sun and Day 5/Mon. However, specific during this period, and particularly beyond, are quite nebulous. The ECMWF cuts off an upper low across the Ohio Valley vicinity on Saturday Night while the GFS waits to cut off the upper-low across the Southeast US on Monday/Tuesday. Farther west there is more consistency in the upper pattern with a cutoff low in the Southwest vicinity. Enhanced southwesterly flow could result in several days of severe weather in the southern Plains. However, moisture remains uncertain due to aforementioned timing/location differences for the mid-level trough in the East. The GFS solution results in a more progressive cold front which clears out most of the greater moisture from the Gulf. However, the ECMWF stalls the front across the central Gulf which leaves a reservoir of rich theta-e which can be advected across Texas and vicinity during the early-mid part of next week. Therefore, predictability remains too low for probabilities at this time, but once the upper-level pattern becomes more clear, probabilities may be necessary. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0355 AM CDT Thu May 01 2025 Valid 041200Z - 091200Z ...DISCUSSION... High pressure will dominate much of the eastern CONUS at the start of the extended period. This will shift most moisture into the Atlantic/Gulf of America. The only exception will be across Texas where east-southeasterly flow will advect richer low-level moisture into the southern High Plains. This will be the focus for any potential severe storms on Day 4/Sun and Day 5/Mon. However, specific during this period, and particularly beyond, are quite nebulous. The ECMWF cuts off an upper low across the Ohio Valley vicinity on Saturday Night while the GFS waits to cut off the upper-low across the Southeast US on Monday/Tuesday. Farther west there is more consistency in the upper pattern with a cutoff low in the Southwest vicinity. Enhanced southwesterly flow could result in several days of severe weather in the southern Plains. However, moisture remains uncertain due to aforementioned timing/location differences for the mid-level trough in the East. The GFS solution results in a more progressive cold front which clears out most of the greater moisture from the Gulf. However, the ECMWF stalls the front across the central Gulf which leaves a reservoir of rich theta-e which can be advected across Texas and vicinity during the early-mid part of next week. Therefore, predictability remains too low for probabilities at this time, but once the upper-level pattern becomes more clear, probabilities may be necessary. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0355 AM CDT Thu May 01 2025 Valid 041200Z - 091200Z ...DISCUSSION... High pressure will dominate much of the eastern CONUS at the start of the extended period. This will shift most moisture into the Atlantic/Gulf of America. The only exception will be across Texas where east-southeasterly flow will advect richer low-level moisture into the southern High Plains. This will be the focus for any potential severe storms on Day 4/Sun and Day 5/Mon. However, specific during this period, and particularly beyond, are quite nebulous. The ECMWF cuts off an upper low across the Ohio Valley vicinity on Saturday Night while the GFS waits to cut off the upper-low across the Southeast US on Monday/Tuesday. Farther west there is more consistency in the upper pattern with a cutoff low in the Southwest vicinity. Enhanced southwesterly flow could result in several days of severe weather in the southern Plains. However, moisture remains uncertain due to aforementioned timing/location differences for the mid-level trough in the East. The GFS solution results in a more progressive cold front which clears out most of the greater moisture from the Gulf. However, the ECMWF stalls the front across the central Gulf which leaves a reservoir of rich theta-e which can be advected across Texas and vicinity during the early-mid part of next week. Therefore, predictability remains too low for probabilities at this time, but once the upper-level pattern becomes more clear, probabilities may be necessary. Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0216 AM CDT Thu May 01 2025 Valid 031200Z - 041200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR FAR SOUTH TEXAS AND FROM THE SOUTHEAST TO NEW ENGLAND... ...SUMMARY... Isolated strong to severe storms are possible on Saturday from the Southeast to New England and across far South Texas. ...Synopsis... A mid-level trough will move from the Great Lakes to the Northeast on Saturday. At the surface a cold front will advance across the Appalachians and eventually off the Atlantic Coast and will also extend westward near the Gulf Coast, and into South Texas. High pressure will build into the Midwest in the wake of this cold front. ...East Coast... Scattered thunderstorms are expected to develop along and ahead of a cold front during the afternoon as some destabilization occurs east of the Appalachians. An expansive area of upper 50s to low 60s dewpoints will be present east of the Appalachians on Saturday. Some heating is expected during the afternoon which may lead to weak to potentially moderate instability. Mid-level lapse rates are forecast to be weak with only marginally strong shear. Given this environment, a few multicell storms are possible along and ahead of the eastward advancing cold front. However, more widespread coverage of severe storms is not anticipated at this time. ...Far South Texas... Thunderstorms will likely be ongoing at the beginning of the period along a front as it moves south across Texas. A very moist airmass with steep mid-level lapse rates will be in place with 45 to 50 knots of deep-layer shear. Therefore, organized storms, including the potential for supercells exists during the morning hours Saturday before the front moves into northern Mexico/the Gulf. ..Bentley.. 05/01/2025 Read more