Severe Storms

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1124 AM CDT Thu Sep 05 2024 Valid 051630Z - 061200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF FAR SOUTH-CENTRAL COLORADO INTO NORTHERN/CENTRAL NEW MEXICO... ...SUMMARY... Thunderstorms capable of producing isolated severe wind gusts and hail will be possible today across parts of far south-central Colorado into northern/central New Mexico. ...Synopsis... Satellite imagery shows a shortwave trough moving southeastward through the central Rockies, between the upper ridging in place over the western Great Basin and the broad upper troughing across central Canadian and northern Plains/Upper MS Valley. Another shortwave trough exists over the Upper MS Valley. This shortwave trough is forecast to continue progressing eastward through the base broad central Canada/northern Plains trough, moving across the Upper Great Lakes and into eastern Ontario. Recent surface analysis places a surface low associated with this shortwave over Lake Superior, with a cold front extending southwestward from this low through KS and into northeast NM. This front is forecast to progress southward/southeastward as its parent surface low lifts northeastward. Isolated thunderstorms are possible along this frontal boundary, but overall severity should be mitigated by modest buoyancy and vertical shear. Greater thunderstorm coverage and severity is anticipated over the southern Rockies as the previously mentioned central Rockies shortwave trough continues southeastward and promotes thunderstorm development. Lastly, a tropical wave just off the TX Coast is contributing to abundant moisture across much of Gulf Coast, with low 70s dewpoints reaching into much of east TX and northern LA, and upper 70s across FL. Precipitable water values over 2" cover much of this region as well. Heavy rain is the primary threat (as indicated by the latest Day 1 Excessive Rainfall Outlook from WPC), but a few water-loaded downbursts capable of damaging gusts are possible from southeast TX and southern/central LA eastward along the Gulf Coast and over the Florida Peninsula. Coverage of these gusts is expected to be sparse and too low to delineate a 5% wind probability area. ...Southern Rockies/southern High Plains... Moderate low-level moisture is anticipated within the post-frontal airmass across the southern Rockies and adjacent southern High Plains this afternoon, characterized by dewpoints in the low to mid 50s across the High Plains and upper 40s across the higher terrain. Even with this modest moisture, the airmass is expected to destabilize, fostered by deep boundary-layer mixing and cool temperatures aloft (i.e. around -10 deg C at 500 mb). Surface easterlies/northeasterlies beneath modest westerlies aloft will contribute to effective bulk shear around 35 kt, which is strong enough for some updraft organization. Isolated hail is possible across the higher terrain with the initially more cellular development. Damaging gusts are expected to be the primary risk thereafter as storms trend towards a more clustered mode and move eastward into the more mixed southern High Plains. ..Mosier/Squitieri.. 09/05/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1124 AM CDT Thu Sep 05 2024 Valid 051630Z - 061200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF FAR SOUTH-CENTRAL COLORADO INTO NORTHERN/CENTRAL NEW MEXICO... ...SUMMARY... Thunderstorms capable of producing isolated severe wind gusts and hail will be possible today across parts of far south-central Colorado into northern/central New Mexico. ...Synopsis... Satellite imagery shows a shortwave trough moving southeastward through the central Rockies, between the upper ridging in place over the western Great Basin and the broad upper troughing across central Canadian and northern Plains/Upper MS Valley. Another shortwave trough exists over the Upper MS Valley. This shortwave trough is forecast to continue progressing eastward through the base broad central Canada/northern Plains trough, moving across the Upper Great Lakes and into eastern Ontario. Recent surface analysis places a surface low associated with this shortwave over Lake Superior, with a cold front extending southwestward from this low through KS and into northeast NM. This front is forecast to progress southward/southeastward as its parent surface low lifts northeastward. Isolated thunderstorms are possible along this frontal boundary, but overall severity should be mitigated by modest buoyancy and vertical shear. Greater thunderstorm coverage and severity is anticipated over the southern Rockies as the previously mentioned central Rockies shortwave trough continues southeastward and promotes thunderstorm development. Lastly, a tropical wave just off the TX Coast is contributing to abundant moisture across much of Gulf Coast, with low 70s dewpoints reaching into much of east TX and northern LA, and upper 70s across FL. Precipitable water values over 2" cover much of this region as well. Heavy rain is the primary threat (as indicated by the latest Day 1 Excessive Rainfall Outlook from WPC), but a few water-loaded downbursts capable of damaging gusts are possible from southeast TX and southern/central LA eastward along the Gulf Coast and over the Florida Peninsula. Coverage of these gusts is expected to be sparse and too low to delineate a 5% wind probability area. ...Southern Rockies/southern High Plains... Moderate low-level moisture is anticipated within the post-frontal airmass across the southern Rockies and adjacent southern High Plains this afternoon, characterized by dewpoints in the low to mid 50s across the High Plains and upper 40s across the higher terrain. Even with this modest moisture, the airmass is expected to destabilize, fostered by deep boundary-layer mixing and cool temperatures aloft (i.e. around -10 deg C at 500 mb). Surface easterlies/northeasterlies beneath modest westerlies aloft will contribute to effective bulk shear around 35 kt, which is strong enough for some updraft organization. Isolated hail is possible across the higher terrain with the initially more cellular development. Damaging gusts are expected to be the primary risk thereafter as storms trend towards a more clustered mode and move eastward into the more mixed southern High Plains. ..Mosier/Squitieri.. 09/05/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1124 AM CDT Thu Sep 05 2024 Valid 051630Z - 061200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF FAR SOUTH-CENTRAL COLORADO INTO NORTHERN/CENTRAL NEW MEXICO... ...SUMMARY... Thunderstorms capable of producing isolated severe wind gusts and hail will be possible today across parts of far south-central Colorado into northern/central New Mexico. ...Synopsis... Satellite imagery shows a shortwave trough moving southeastward through the central Rockies, between the upper ridging in place over the western Great Basin and the broad upper troughing across central Canadian and northern Plains/Upper MS Valley. Another shortwave trough exists over the Upper MS Valley. This shortwave trough is forecast to continue progressing eastward through the base broad central Canada/northern Plains trough, moving across the Upper Great Lakes and into eastern Ontario. Recent surface analysis places a surface low associated with this shortwave over Lake Superior, with a cold front extending southwestward from this low through KS and into northeast NM. This front is forecast to progress southward/southeastward as its parent surface low lifts northeastward. Isolated thunderstorms are possible along this frontal boundary, but overall severity should be mitigated by modest buoyancy and vertical shear. Greater thunderstorm coverage and severity is anticipated over the southern Rockies as the previously mentioned central Rockies shortwave trough continues southeastward and promotes thunderstorm development. Lastly, a tropical wave just off the TX Coast is contributing to abundant moisture across much of Gulf Coast, with low 70s dewpoints reaching into much of east TX and northern LA, and upper 70s across FL. Precipitable water values over 2" cover much of this region as well. Heavy rain is the primary threat (as indicated by the latest Day 1 Excessive Rainfall Outlook from WPC), but a few water-loaded downbursts capable of damaging gusts are possible from southeast TX and southern/central LA eastward along the Gulf Coast and over the Florida Peninsula. Coverage of these gusts is expected to be sparse and too low to delineate a 5% wind probability area. ...Southern Rockies/southern High Plains... Moderate low-level moisture is anticipated within the post-frontal airmass across the southern Rockies and adjacent southern High Plains this afternoon, characterized by dewpoints in the low to mid 50s across the High Plains and upper 40s across the higher terrain. Even with this modest moisture, the airmass is expected to destabilize, fostered by deep boundary-layer mixing and cool temperatures aloft (i.e. around -10 deg C at 500 mb). Surface easterlies/northeasterlies beneath modest westerlies aloft will contribute to effective bulk shear around 35 kt, which is strong enough for some updraft organization. Isolated hail is possible across the higher terrain with the initially more cellular development. Damaging gusts are expected to be the primary risk thereafter as storms trend towards a more clustered mode and move eastward into the more mixed southern High Plains. ..Mosier/Squitieri.. 09/05/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0742 AM CDT Thu Sep 05 2024 Valid 051300Z - 061200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF FAR SOUTH-CENTRAL COLORADO INTO NORTHERN/CENTRAL NEW MEXICO... ...SUMMARY... Thunderstorms capable of producing isolated severe wind gusts and hail will be possible today across parts of far south-central Colorado into northern/central New Mexico. ...Central/Southern Rockies into the Southern High Plains... On the southwest fringe of large-scale upper troughing over Canada and the northern Plains/Upper Midwest, a mid-level shortwave trough over the central Rockies this morning will move generally southward across NM and vicinity through the day. Even though low-level moisture remains fairly modest across the southern Rockies and adjacent High Plains along/near of a cold front, cool mid-level temperatures and somewhat steepened lapse rates aloft will likely contribute to the development of around 500-750 J/kg of MLCAPE by early afternoon as daytime heating occurs. Initial development of robust convection by around 18-19Z will likely be tied to the higher terrain as weak large-scale ascent associated with the shortwave trough overspreads the south-central Rockies in a low-level post-frontal regime. This activity should then spread generally south-southeastward across parts of northern/central NM through the late afternoon and into the evening. While low-level easterly flow ahead of the front is forecast to remain weak, veering winds with height through mid/upper levels should still support around 25-35 kt of effective bulk shear and some updraft organization. The strongest cores that can develop may be capable of producing severe hail. Otherwise, the threat for isolated strong to severe wind gusts should spread southward in tandem with any small clusters that can form. ...Great Lakes/Midwest to the Central Plains... Generally elevated convection is ongoing this morning across parts of the Upper Midwest along and near a surface cold front, and ahead of a large-scale upper trough moving generally southeastward. Instability across this region is expected to remain weak (MUCAPE 500 J/kg or less), which should tend to limit the overall severe threat. Still, some of the stronger cores could produce small hail or gusty winds in the short term. Other thunderstorms may eventually develop this afternoon along/near the front across parts of the Midwest and/or central Plains. Regardless, the overall severe threat across these regions currently appears too limited to introduce low severe probabilities. ..Gleason/Leitman.. 09/05/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0742 AM CDT Thu Sep 05 2024 Valid 051300Z - 061200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF FAR SOUTH-CENTRAL COLORADO INTO NORTHERN/CENTRAL NEW MEXICO... ...SUMMARY... Thunderstorms capable of producing isolated severe wind gusts and hail will be possible today across parts of far south-central Colorado into northern/central New Mexico. ...Central/Southern Rockies into the Southern High Plains... On the southwest fringe of large-scale upper troughing over Canada and the northern Plains/Upper Midwest, a mid-level shortwave trough over the central Rockies this morning will move generally southward across NM and vicinity through the day. Even though low-level moisture remains fairly modest across the southern Rockies and adjacent High Plains along/near of a cold front, cool mid-level temperatures and somewhat steepened lapse rates aloft will likely contribute to the development of around 500-750 J/kg of MLCAPE by early afternoon as daytime heating occurs. Initial development of robust convection by around 18-19Z will likely be tied to the higher terrain as weak large-scale ascent associated with the shortwave trough overspreads the south-central Rockies in a low-level post-frontal regime. This activity should then spread generally south-southeastward across parts of northern/central NM through the late afternoon and into the evening. While low-level easterly flow ahead of the front is forecast to remain weak, veering winds with height through mid/upper levels should still support around 25-35 kt of effective bulk shear and some updraft organization. The strongest cores that can develop may be capable of producing severe hail. Otherwise, the threat for isolated strong to severe wind gusts should spread southward in tandem with any small clusters that can form. ...Great Lakes/Midwest to the Central Plains... Generally elevated convection is ongoing this morning across parts of the Upper Midwest along and near a surface cold front, and ahead of a large-scale upper trough moving generally southeastward. Instability across this region is expected to remain weak (MUCAPE 500 J/kg or less), which should tend to limit the overall severe threat. Still, some of the stronger cores could produce small hail or gusty winds in the short term. Other thunderstorms may eventually develop this afternoon along/near the front across parts of the Midwest and/or central Plains. Regardless, the overall severe threat across these regions currently appears too limited to introduce low severe probabilities. ..Gleason/Leitman.. 09/05/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0742 AM CDT Thu Sep 05 2024 Valid 051300Z - 061200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF FAR SOUTH-CENTRAL COLORADO INTO NORTHERN/CENTRAL NEW MEXICO... ...SUMMARY... Thunderstorms capable of producing isolated severe wind gusts and hail will be possible today across parts of far south-central Colorado into northern/central New Mexico. ...Central/Southern Rockies into the Southern High Plains... On the southwest fringe of large-scale upper troughing over Canada and the northern Plains/Upper Midwest, a mid-level shortwave trough over the central Rockies this morning will move generally southward across NM and vicinity through the day. Even though low-level moisture remains fairly modest across the southern Rockies and adjacent High Plains along/near of a cold front, cool mid-level temperatures and somewhat steepened lapse rates aloft will likely contribute to the development of around 500-750 J/kg of MLCAPE by early afternoon as daytime heating occurs. Initial development of robust convection by around 18-19Z will likely be tied to the higher terrain as weak large-scale ascent associated with the shortwave trough overspreads the south-central Rockies in a low-level post-frontal regime. This activity should then spread generally south-southeastward across parts of northern/central NM through the late afternoon and into the evening. While low-level easterly flow ahead of the front is forecast to remain weak, veering winds with height through mid/upper levels should still support around 25-35 kt of effective bulk shear and some updraft organization. The strongest cores that can develop may be capable of producing severe hail. Otherwise, the threat for isolated strong to severe wind gusts should spread southward in tandem with any small clusters that can form. ...Great Lakes/Midwest to the Central Plains... Generally elevated convection is ongoing this morning across parts of the Upper Midwest along and near a surface cold front, and ahead of a large-scale upper trough moving generally southeastward. Instability across this region is expected to remain weak (MUCAPE 500 J/kg or less), which should tend to limit the overall severe threat. Still, some of the stronger cores could produce small hail or gusty winds in the short term. Other thunderstorms may eventually develop this afternoon along/near the front across parts of the Midwest and/or central Plains. Regardless, the overall severe threat across these regions currently appears too limited to introduce low severe probabilities. ..Gleason/Leitman.. 09/05/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0742 AM CDT Thu Sep 05 2024 Valid 051300Z - 061200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF FAR SOUTH-CENTRAL COLORADO INTO NORTHERN/CENTRAL NEW MEXICO... ...SUMMARY... Thunderstorms capable of producing isolated severe wind gusts and hail will be possible today across parts of far south-central Colorado into northern/central New Mexico. ...Central/Southern Rockies into the Southern High Plains... On the southwest fringe of large-scale upper troughing over Canada and the northern Plains/Upper Midwest, a mid-level shortwave trough over the central Rockies this morning will move generally southward across NM and vicinity through the day. Even though low-level moisture remains fairly modest across the southern Rockies and adjacent High Plains along/near of a cold front, cool mid-level temperatures and somewhat steepened lapse rates aloft will likely contribute to the development of around 500-750 J/kg of MLCAPE by early afternoon as daytime heating occurs. Initial development of robust convection by around 18-19Z will likely be tied to the higher terrain as weak large-scale ascent associated with the shortwave trough overspreads the south-central Rockies in a low-level post-frontal regime. This activity should then spread generally south-southeastward across parts of northern/central NM through the late afternoon and into the evening. While low-level easterly flow ahead of the front is forecast to remain weak, veering winds with height through mid/upper levels should still support around 25-35 kt of effective bulk shear and some updraft organization. The strongest cores that can develop may be capable of producing severe hail. Otherwise, the threat for isolated strong to severe wind gusts should spread southward in tandem with any small clusters that can form. ...Great Lakes/Midwest to the Central Plains... Generally elevated convection is ongoing this morning across parts of the Upper Midwest along and near a surface cold front, and ahead of a large-scale upper trough moving generally southeastward. Instability across this region is expected to remain weak (MUCAPE 500 J/kg or less), which should tend to limit the overall severe threat. Still, some of the stronger cores could produce small hail or gusty winds in the short term. Other thunderstorms may eventually develop this afternoon along/near the front across parts of the Midwest and/or central Plains. Regardless, the overall severe threat across these regions currently appears too limited to introduce low severe probabilities. ..Gleason/Leitman.. 09/05/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0742 AM CDT Thu Sep 05 2024 Valid 051300Z - 061200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF FAR SOUTH-CENTRAL COLORADO INTO NORTHERN/CENTRAL NEW MEXICO... ...SUMMARY... Thunderstorms capable of producing isolated severe wind gusts and hail will be possible today across parts of far south-central Colorado into northern/central New Mexico. ...Central/Southern Rockies into the Southern High Plains... On the southwest fringe of large-scale upper troughing over Canada and the northern Plains/Upper Midwest, a mid-level shortwave trough over the central Rockies this morning will move generally southward across NM and vicinity through the day. Even though low-level moisture remains fairly modest across the southern Rockies and adjacent High Plains along/near of a cold front, cool mid-level temperatures and somewhat steepened lapse rates aloft will likely contribute to the development of around 500-750 J/kg of MLCAPE by early afternoon as daytime heating occurs. Initial development of robust convection by around 18-19Z will likely be tied to the higher terrain as weak large-scale ascent associated with the shortwave trough overspreads the south-central Rockies in a low-level post-frontal regime. This activity should then spread generally south-southeastward across parts of northern/central NM through the late afternoon and into the evening. While low-level easterly flow ahead of the front is forecast to remain weak, veering winds with height through mid/upper levels should still support around 25-35 kt of effective bulk shear and some updraft organization. The strongest cores that can develop may be capable of producing severe hail. Otherwise, the threat for isolated strong to severe wind gusts should spread southward in tandem with any small clusters that can form. ...Great Lakes/Midwest to the Central Plains... Generally elevated convection is ongoing this morning across parts of the Upper Midwest along and near a surface cold front, and ahead of a large-scale upper trough moving generally southeastward. Instability across this region is expected to remain weak (MUCAPE 500 J/kg or less), which should tend to limit the overall severe threat. Still, some of the stronger cores could produce small hail or gusty winds in the short term. Other thunderstorms may eventually develop this afternoon along/near the front across parts of the Midwest and/or central Plains. Regardless, the overall severe threat across these regions currently appears too limited to introduce low severe probabilities. ..Gleason/Leitman.. 09/05/2024 Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0313 AM CDT Thu Sep 05 2024 Valid 081200Z - 131200Z ...DISCUSSION... A deep upper-level trough initially over the eastern CONUS on D4/Sunday is forecast to move offshore early next week. In the wake of this trough and its attendant cold front, a surface ridge is expected to persist over much of the eastern CONUS through mid week. This ridge will likely prevent the northward return of richer low-level moisture for most of the extended-range period, which should tend to limit organized severe-thunderstorm potential across much of the CONUS. There is some potential for the influence of the eastern surface ridge to wane by D7/Wednesday into D8/Thursday, while some guidance suggests a mid/upper-level trough will approach the central/northern High Plains during this time frame. Should this occur, there could be some increase in severe potential, though predictability remains rather low at this forecast range. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0313 AM CDT Thu Sep 05 2024 Valid 081200Z - 131200Z ...DISCUSSION... A deep upper-level trough initially over the eastern CONUS on D4/Sunday is forecast to move offshore early next week. In the wake of this trough and its attendant cold front, a surface ridge is expected to persist over much of the eastern CONUS through mid week. This ridge will likely prevent the northward return of richer low-level moisture for most of the extended-range period, which should tend to limit organized severe-thunderstorm potential across much of the CONUS. There is some potential for the influence of the eastern surface ridge to wane by D7/Wednesday into D8/Thursday, while some guidance suggests a mid/upper-level trough will approach the central/northern High Plains during this time frame. Should this occur, there could be some increase in severe potential, though predictability remains rather low at this forecast range. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0313 AM CDT Thu Sep 05 2024 Valid 081200Z - 131200Z ...DISCUSSION... A deep upper-level trough initially over the eastern CONUS on D4/Sunday is forecast to move offshore early next week. In the wake of this trough and its attendant cold front, a surface ridge is expected to persist over much of the eastern CONUS through mid week. This ridge will likely prevent the northward return of richer low-level moisture for most of the extended-range period, which should tend to limit organized severe-thunderstorm potential across much of the CONUS. There is some potential for the influence of the eastern surface ridge to wane by D7/Wednesday into D8/Thursday, while some guidance suggests a mid/upper-level trough will approach the central/northern High Plains during this time frame. Should this occur, there could be some increase in severe potential, though predictability remains rather low at this forecast range. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0313 AM CDT Thu Sep 05 2024 Valid 081200Z - 131200Z ...DISCUSSION... A deep upper-level trough initially over the eastern CONUS on D4/Sunday is forecast to move offshore early next week. In the wake of this trough and its attendant cold front, a surface ridge is expected to persist over much of the eastern CONUS through mid week. This ridge will likely prevent the northward return of richer low-level moisture for most of the extended-range period, which should tend to limit organized severe-thunderstorm potential across much of the CONUS. There is some potential for the influence of the eastern surface ridge to wane by D7/Wednesday into D8/Thursday, while some guidance suggests a mid/upper-level trough will approach the central/northern High Plains during this time frame. Should this occur, there could be some increase in severe potential, though predictability remains rather low at this forecast range. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0313 AM CDT Thu Sep 05 2024 Valid 081200Z - 131200Z ...DISCUSSION... A deep upper-level trough initially over the eastern CONUS on D4/Sunday is forecast to move offshore early next week. In the wake of this trough and its attendant cold front, a surface ridge is expected to persist over much of the eastern CONUS through mid week. This ridge will likely prevent the northward return of richer low-level moisture for most of the extended-range period, which should tend to limit organized severe-thunderstorm potential across much of the CONUS. There is some potential for the influence of the eastern surface ridge to wane by D7/Wednesday into D8/Thursday, while some guidance suggests a mid/upper-level trough will approach the central/northern High Plains during this time frame. Should this occur, there could be some increase in severe potential, though predictability remains rather low at this forecast range. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0313 AM CDT Thu Sep 05 2024 Valid 081200Z - 131200Z ...DISCUSSION... A deep upper-level trough initially over the eastern CONUS on D4/Sunday is forecast to move offshore early next week. In the wake of this trough and its attendant cold front, a surface ridge is expected to persist over much of the eastern CONUS through mid week. This ridge will likely prevent the northward return of richer low-level moisture for most of the extended-range period, which should tend to limit organized severe-thunderstorm potential across much of the CONUS. There is some potential for the influence of the eastern surface ridge to wane by D7/Wednesday into D8/Thursday, while some guidance suggests a mid/upper-level trough will approach the central/northern High Plains during this time frame. Should this occur, there could be some increase in severe potential, though predictability remains rather low at this forecast range. Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0229 AM CDT Thu Sep 05 2024 Valid 071200Z - 081200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A few strong storms are possible across parts of the Northeast and Mid Atlantic on Saturday. ...Synopsis... A deep trough is forecast to take on more of a neutral or negative tilt on Saturday, as an embedded mid/upper-level cyclone moves slowly eastward across parts of ON/QC. A surface low initially near the lower Great Lakes may gradually deepen as it moves northeastward, while a trailing cold front will move through parts of the Northeast and Mid Atlantic through the day and into the evening. Farther south, a gradually deepening frontal wave is forecast to move near the Carolina coast through the day, and then move offshore by evening. To the west, an upper-level ridge is forecast to remain in place across the Southwest, while an upper-level trough moves slowly eastward across northern CA and the Pacific Northwest. ...Parts of the Northeast/Mid Atlantic... Some modest low-level moisture return is possible along/ahead of the front across the Mid Atlantic and Northeast, though buoyancy will likely remain meager due to weak midlevel lapse rates, and timing of the front remains somewhat uncertain. If adequate destabilization can occur along/ahead of the front, then increasing low/midlevel flow and large-scale ascent would support potential for somewhat organized convection during the day across parts of the Northeast and Mid Atlantic, which could pose some damaging-wind potential. Severe probabilities may eventually be needed for parts of the region, if confidence increases regarding frontal timing and development of sufficient instability. ...Central/southern High Plains vicinity... Modest low-level moisture return (dewpoints generally in the low 50s F) beneath relatively steep midlevel lapse rates will support moderate destabilization across parts of the central/southern High Plains. Deep-layer shear will become at least marginally supportive of organized storms within a modest northwesterly flow regime. Storm development and coverage (if any) across the High Plains remains uncertain, with large-scale ascent likely to remain subtle at best. Diurnal storm development will also be possible across the higher terrain of the southern/central Rockies, though buoyancy and deep-layer shear will tend to be somewhat weaker compared to areas farther east. ...Coastal NC... Depending on the track of the frontal wave that is forecast to develop Friday night near the coastal Carolinas, rich low-level moisture may spread slightly inland during the morning/afternoon, before the low moves offshore. While some increase in low-level flow is expected as the wave gradually deepens, buoyancy will likely remain quite weak. Any severe potential with the system may be rather limited, unless low-level mass response ends up being stronger than currently forecast. ..Dean.. 09/05/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0229 AM CDT Thu Sep 05 2024 Valid 071200Z - 081200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A few strong storms are possible across parts of the Northeast and Mid Atlantic on Saturday. ...Synopsis... A deep trough is forecast to take on more of a neutral or negative tilt on Saturday, as an embedded mid/upper-level cyclone moves slowly eastward across parts of ON/QC. A surface low initially near the lower Great Lakes may gradually deepen as it moves northeastward, while a trailing cold front will move through parts of the Northeast and Mid Atlantic through the day and into the evening. Farther south, a gradually deepening frontal wave is forecast to move near the Carolina coast through the day, and then move offshore by evening. To the west, an upper-level ridge is forecast to remain in place across the Southwest, while an upper-level trough moves slowly eastward across northern CA and the Pacific Northwest. ...Parts of the Northeast/Mid Atlantic... Some modest low-level moisture return is possible along/ahead of the front across the Mid Atlantic and Northeast, though buoyancy will likely remain meager due to weak midlevel lapse rates, and timing of the front remains somewhat uncertain. If adequate destabilization can occur along/ahead of the front, then increasing low/midlevel flow and large-scale ascent would support potential for somewhat organized convection during the day across parts of the Northeast and Mid Atlantic, which could pose some damaging-wind potential. Severe probabilities may eventually be needed for parts of the region, if confidence increases regarding frontal timing and development of sufficient instability. ...Central/southern High Plains vicinity... Modest low-level moisture return (dewpoints generally in the low 50s F) beneath relatively steep midlevel lapse rates will support moderate destabilization across parts of the central/southern High Plains. Deep-layer shear will become at least marginally supportive of organized storms within a modest northwesterly flow regime. Storm development and coverage (if any) across the High Plains remains uncertain, with large-scale ascent likely to remain subtle at best. Diurnal storm development will also be possible across the higher terrain of the southern/central Rockies, though buoyancy and deep-layer shear will tend to be somewhat weaker compared to areas farther east. ...Coastal NC... Depending on the track of the frontal wave that is forecast to develop Friday night near the coastal Carolinas, rich low-level moisture may spread slightly inland during the morning/afternoon, before the low moves offshore. While some increase in low-level flow is expected as the wave gradually deepens, buoyancy will likely remain quite weak. Any severe potential with the system may be rather limited, unless low-level mass response ends up being stronger than currently forecast. ..Dean.. 09/05/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0229 AM CDT Thu Sep 05 2024 Valid 071200Z - 081200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A few strong storms are possible across parts of the Northeast and Mid Atlantic on Saturday. ...Synopsis... A deep trough is forecast to take on more of a neutral or negative tilt on Saturday, as an embedded mid/upper-level cyclone moves slowly eastward across parts of ON/QC. A surface low initially near the lower Great Lakes may gradually deepen as it moves northeastward, while a trailing cold front will move through parts of the Northeast and Mid Atlantic through the day and into the evening. Farther south, a gradually deepening frontal wave is forecast to move near the Carolina coast through the day, and then move offshore by evening. To the west, an upper-level ridge is forecast to remain in place across the Southwest, while an upper-level trough moves slowly eastward across northern CA and the Pacific Northwest. ...Parts of the Northeast/Mid Atlantic... Some modest low-level moisture return is possible along/ahead of the front across the Mid Atlantic and Northeast, though buoyancy will likely remain meager due to weak midlevel lapse rates, and timing of the front remains somewhat uncertain. If adequate destabilization can occur along/ahead of the front, then increasing low/midlevel flow and large-scale ascent would support potential for somewhat organized convection during the day across parts of the Northeast and Mid Atlantic, which could pose some damaging-wind potential. Severe probabilities may eventually be needed for parts of the region, if confidence increases regarding frontal timing and development of sufficient instability. ...Central/southern High Plains vicinity... Modest low-level moisture return (dewpoints generally in the low 50s F) beneath relatively steep midlevel lapse rates will support moderate destabilization across parts of the central/southern High Plains. Deep-layer shear will become at least marginally supportive of organized storms within a modest northwesterly flow regime. Storm development and coverage (if any) across the High Plains remains uncertain, with large-scale ascent likely to remain subtle at best. Diurnal storm development will also be possible across the higher terrain of the southern/central Rockies, though buoyancy and deep-layer shear will tend to be somewhat weaker compared to areas farther east. ...Coastal NC... Depending on the track of the frontal wave that is forecast to develop Friday night near the coastal Carolinas, rich low-level moisture may spread slightly inland during the morning/afternoon, before the low moves offshore. While some increase in low-level flow is expected as the wave gradually deepens, buoyancy will likely remain quite weak. Any severe potential with the system may be rather limited, unless low-level mass response ends up being stronger than currently forecast. ..Dean.. 09/05/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0229 AM CDT Thu Sep 05 2024 Valid 071200Z - 081200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A few strong storms are possible across parts of the Northeast and Mid Atlantic on Saturday. ...Synopsis... A deep trough is forecast to take on more of a neutral or negative tilt on Saturday, as an embedded mid/upper-level cyclone moves slowly eastward across parts of ON/QC. A surface low initially near the lower Great Lakes may gradually deepen as it moves northeastward, while a trailing cold front will move through parts of the Northeast and Mid Atlantic through the day and into the evening. Farther south, a gradually deepening frontal wave is forecast to move near the Carolina coast through the day, and then move offshore by evening. To the west, an upper-level ridge is forecast to remain in place across the Southwest, while an upper-level trough moves slowly eastward across northern CA and the Pacific Northwest. ...Parts of the Northeast/Mid Atlantic... Some modest low-level moisture return is possible along/ahead of the front across the Mid Atlantic and Northeast, though buoyancy will likely remain meager due to weak midlevel lapse rates, and timing of the front remains somewhat uncertain. If adequate destabilization can occur along/ahead of the front, then increasing low/midlevel flow and large-scale ascent would support potential for somewhat organized convection during the day across parts of the Northeast and Mid Atlantic, which could pose some damaging-wind potential. Severe probabilities may eventually be needed for parts of the region, if confidence increases regarding frontal timing and development of sufficient instability. ...Central/southern High Plains vicinity... Modest low-level moisture return (dewpoints generally in the low 50s F) beneath relatively steep midlevel lapse rates will support moderate destabilization across parts of the central/southern High Plains. Deep-layer shear will become at least marginally supportive of organized storms within a modest northwesterly flow regime. Storm development and coverage (if any) across the High Plains remains uncertain, with large-scale ascent likely to remain subtle at best. Diurnal storm development will also be possible across the higher terrain of the southern/central Rockies, though buoyancy and deep-layer shear will tend to be somewhat weaker compared to areas farther east. ...Coastal NC... Depending on the track of the frontal wave that is forecast to develop Friday night near the coastal Carolinas, rich low-level moisture may spread slightly inland during the morning/afternoon, before the low moves offshore. While some increase in low-level flow is expected as the wave gradually deepens, buoyancy will likely remain quite weak. Any severe potential with the system may be rather limited, unless low-level mass response ends up being stronger than currently forecast. ..Dean.. 09/05/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0229 AM CDT Thu Sep 05 2024 Valid 071200Z - 081200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A few strong storms are possible across parts of the Northeast and Mid Atlantic on Saturday. ...Synopsis... A deep trough is forecast to take on more of a neutral or negative tilt on Saturday, as an embedded mid/upper-level cyclone moves slowly eastward across parts of ON/QC. A surface low initially near the lower Great Lakes may gradually deepen as it moves northeastward, while a trailing cold front will move through parts of the Northeast and Mid Atlantic through the day and into the evening. Farther south, a gradually deepening frontal wave is forecast to move near the Carolina coast through the day, and then move offshore by evening. To the west, an upper-level ridge is forecast to remain in place across the Southwest, while an upper-level trough moves slowly eastward across northern CA and the Pacific Northwest. ...Parts of the Northeast/Mid Atlantic... Some modest low-level moisture return is possible along/ahead of the front across the Mid Atlantic and Northeast, though buoyancy will likely remain meager due to weak midlevel lapse rates, and timing of the front remains somewhat uncertain. If adequate destabilization can occur along/ahead of the front, then increasing low/midlevel flow and large-scale ascent would support potential for somewhat organized convection during the day across parts of the Northeast and Mid Atlantic, which could pose some damaging-wind potential. Severe probabilities may eventually be needed for parts of the region, if confidence increases regarding frontal timing and development of sufficient instability. ...Central/southern High Plains vicinity... Modest low-level moisture return (dewpoints generally in the low 50s F) beneath relatively steep midlevel lapse rates will support moderate destabilization across parts of the central/southern High Plains. Deep-layer shear will become at least marginally supportive of organized storms within a modest northwesterly flow regime. Storm development and coverage (if any) across the High Plains remains uncertain, with large-scale ascent likely to remain subtle at best. Diurnal storm development will also be possible across the higher terrain of the southern/central Rockies, though buoyancy and deep-layer shear will tend to be somewhat weaker compared to areas farther east. ...Coastal NC... Depending on the track of the frontal wave that is forecast to develop Friday night near the coastal Carolinas, rich low-level moisture may spread slightly inland during the morning/afternoon, before the low moves offshore. While some increase in low-level flow is expected as the wave gradually deepens, buoyancy will likely remain quite weak. Any severe potential with the system may be rather limited, unless low-level mass response ends up being stronger than currently forecast. ..Dean.. 09/05/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1252 AM CDT Thu Sep 05 2024 Valid 061200Z - 071200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR MUCH OF OHIO INTO ADJACENT PARTS OF THE GREAT LAKES AND OHIO VALLEY... ...SUMMARY... Strong to locally severe storms are possible on Friday across much of Ohio and adjacent portions of the Great Lakes and Ohio Valley. ...Synopsis... An upper-level trough is forecast to amplify as it digs southeastward across the Great Lakes and Ohio Valley regions on Friday. A mid/upper-level cyclone is forecast to develop with time, as a strong embedded shortwave moves southeastward into the base of the trough by Friday evening. A cold front will move through parts of the Great Lakes, Ohio Valley, Midwest, and southern Plains. Farther south, a weak surface wave may develop along a front near the Gulf Coast and move northeastward along or just offshore of the Carolina coast late Friday night into early Saturday morning. To the west, an upper ridge will remain in place across the Southwest, while a shortwave trough begins to move inland across northern CA into the Pacific Northwest. ...Ohio and adjacent parts of the Great Lakes/Ohio Valley... Thunderstorms are expected to develop near the cold front Friday afternoon across parts of Ohio and vicinity, as the amplifying upper-level trough begins to impinge upon the region. Low-level moisture will likely remain rather limited ahead of the front, though relatively strong heating/mixing will steepen low-level lapse rates. Somewhat more favorable moisture and buoyancy will reside near and immediately behind the front, with MLCAPE potentially approaching or exceeding 1000 J/kg. Low-level flow will likely remain rather weak, but gradually increasing effective shear (generally into the 25-35 kt range) could support a few stronger storms capable of at least isolated damaging winds during the afternoon and perhaps into the evening. Isolated hail also cannot be ruled out with any stronger discrete cells. ...Gulf Coast to the Carolina Coast... Some increase in low-level flow is possible in the vicinity of the frontal wave that may develop near the Gulf Coast and move toward the coastal Carolinas overnight. While this could be accompanied by some increase in low-level shear/SRH, buoyancy is currently expected to remain quite weak, so potential for organized convection inland appears relatively uncertain/limited at this time. ..Dean.. 09/05/2024 Read more