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SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0243 PM CDT Fri Sep 19 2025 Valid 192000Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF FAR SOUTHERN NEBRASKA INTO NORTHWEST AND CENTRAL KANSAS... ...SUMMARY... Isolated severe thunderstorms may impact parts of far southern Nebraska into northwestern and central Kansas late this afternoon and evening, accompanied by some risk for severe hail and wind. ...20z Update... The previous forecast largely remains on track. Latest GOES imagery shows initial thunderstorm development along a weak front across far northwest KS. Ahead of this boundary, modest moisture return across western KS has yielded dewpoints in the upper 50s to low 60s with MLCAPE values increasing to around 1000 J/kg. With temperatures warming into the low 80s, MLCIN is gradually being removed as the front impinges on the returning moisture. Regional VWPs continue to sample 35-40 knot flow at around 4 km AGL, which will support adequate deep-layer shear for organized convection as thunderstorms continue to develop through late afternoon/early evening. Strong/severe thunderstorm coverage remains uncertain with southeastward extent into central KS, but latest observational trends suggest that the severe threat should be relatively greatest across northwest KS through early evening (that said, expected coverage/intensity should remain sufficiently limited to maintain Marginal risk highlights). Elsewhere, the previous forecast (below) remains on track. Instances of sporadic hail and/or wind damage will be possible from eastern AR into northern MS and northwest AL through early evening; however, the convective environment is favorable for mainly short-lived pulse convection (per observed radar trends and regional VWPs), making predictability of any substantial severe threat very limited. ..Moore.. 09/19/2025 .PREV DISCUSSION... /ISSUED 1130 AM CDT Fri Sep 19 2025/ ...Central Plains... Increasing large-scale ascent associated with the embedded shortwave trough and modestly enhanced west-northwesterly jet should influence isolated thunderstorm development by late afternoon/early evening across parts of southwest Nebraska into western Kansas. This region should have a modestly moist low-level airmass in place, with enough daytime heating forecast to support around 1000-1500 J/kg of MLCAPE. Even though mid-level lapse rates are not expected to become overly steep, strong deep-layer shear should aid in convective updraft organization. Any thunderstorms that can form and be sustained could produce isolated severe hail and/or wind gusts as they spread southeastward across western/central Kansas through the evening. ...Midwest/Mississippi Valley... An eastward-moving shortwave trough over the Upper Midwest will more directly influence the middle/upper Mississippi Valley, with moderate destabilization expected this afternoon from the middle Mississippi Valley southward into the Mid-South where MLCAPE will tend to reach 1500-2000 J/kg. Weak deep tropospheric winds will be prevalent along with weak mid-level lapse rates. Even so, some strong to locally severe pulse storms may occur this afternoon through early evening in a broad region spanning parts of Wisconsin/Illinois southward to the Mid-South. ...Western/south-central Minnesota and vicinity... Pending cloud breaks/sufficient heating, scenario may be conducive for funnels and possibly a low chance of a brief tornado in proximity to the upper low and residual surface front, where low-level CAPE/ambient vorticity will be maximized. It is a generally similar regime as to yesterday's reported brief tornado in far southeast North Dakota, although today's setup may be less supportive and more uncertain. ...Southwest States including southeast Arizona... Showers and thunderstorms are ongoing early today across parts of central/eastern Arizona, and on a more isolated basis into western New Mexico and far west Texas. This activity is related to weak ascent aloft associated with minor perturbations rotating through/around a weak upper ridge over the Southwest. Some guidance shows potential for additional robust thunderstorm development by late afternoon/early evening, likely aided by orographic lift and other weak mid-level disturbances. While a localized severe storm or two could occur, substantial uncertainty exists regarding the intensity of these thunderstorms later today owing to ongoing clouds/precipitation, lack of a notable EML, and limited forecast instability. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0243 PM CDT Fri Sep 19 2025 Valid 192000Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF FAR SOUTHERN NEBRASKA INTO NORTHWEST AND CENTRAL KANSAS... ...SUMMARY... Isolated severe thunderstorms may impact parts of far southern Nebraska into northwestern and central Kansas late this afternoon and evening, accompanied by some risk for severe hail and wind. ...20z Update... The previous forecast largely remains on track. Latest GOES imagery shows initial thunderstorm development along a weak front across far northwest KS. Ahead of this boundary, modest moisture return across western KS has yielded dewpoints in the upper 50s to low 60s with MLCAPE values increasing to around 1000 J/kg. With temperatures warming into the low 80s, MLCIN is gradually being removed as the front impinges on the returning moisture. Regional VWPs continue to sample 35-40 knot flow at around 4 km AGL, which will support adequate deep-layer shear for organized convection as thunderstorms continue to develop through late afternoon/early evening. Strong/severe thunderstorm coverage remains uncertain with southeastward extent into central KS, but latest observational trends suggest that the severe threat should be relatively greatest across northwest KS through early evening (that said, expected coverage/intensity should remain sufficiently limited to maintain Marginal risk highlights). Elsewhere, the previous forecast (below) remains on track. Instances of sporadic hail and/or wind damage will be possible from eastern AR into northern MS and northwest AL through early evening; however, the convective environment is favorable for mainly short-lived pulse convection (per observed radar trends and regional VWPs), making predictability of any substantial severe threat very limited. ..Moore.. 09/19/2025 .PREV DISCUSSION... /ISSUED 1130 AM CDT Fri Sep 19 2025/ ...Central Plains... Increasing large-scale ascent associated with the embedded shortwave trough and modestly enhanced west-northwesterly jet should influence isolated thunderstorm development by late afternoon/early evening across parts of southwest Nebraska into western Kansas. This region should have a modestly moist low-level airmass in place, with enough daytime heating forecast to support around 1000-1500 J/kg of MLCAPE. Even though mid-level lapse rates are not expected to become overly steep, strong deep-layer shear should aid in convective updraft organization. Any thunderstorms that can form and be sustained could produce isolated severe hail and/or wind gusts as they spread southeastward across western/central Kansas through the evening. ...Midwest/Mississippi Valley... An eastward-moving shortwave trough over the Upper Midwest will more directly influence the middle/upper Mississippi Valley, with moderate destabilization expected this afternoon from the middle Mississippi Valley southward into the Mid-South where MLCAPE will tend to reach 1500-2000 J/kg. Weak deep tropospheric winds will be prevalent along with weak mid-level lapse rates. Even so, some strong to locally severe pulse storms may occur this afternoon through early evening in a broad region spanning parts of Wisconsin/Illinois southward to the Mid-South. ...Western/south-central Minnesota and vicinity... Pending cloud breaks/sufficient heating, scenario may be conducive for funnels and possibly a low chance of a brief tornado in proximity to the upper low and residual surface front, where low-level CAPE/ambient vorticity will be maximized. It is a generally similar regime as to yesterday's reported brief tornado in far southeast North Dakota, although today's setup may be less supportive and more uncertain. ...Southwest States including southeast Arizona... Showers and thunderstorms are ongoing early today across parts of central/eastern Arizona, and on a more isolated basis into western New Mexico and far west Texas. This activity is related to weak ascent aloft associated with minor perturbations rotating through/around a weak upper ridge over the Southwest. Some guidance shows potential for additional robust thunderstorm development by late afternoon/early evening, likely aided by orographic lift and other weak mid-level disturbances. While a localized severe storm or two could occur, substantial uncertainty exists regarding the intensity of these thunderstorms later today owing to ongoing clouds/precipitation, lack of a notable EML, and limited forecast instability. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0243 PM CDT Fri Sep 19 2025 Valid 192000Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF FAR SOUTHERN NEBRASKA INTO NORTHWEST AND CENTRAL KANSAS... ...SUMMARY... Isolated severe thunderstorms may impact parts of far southern Nebraska into northwestern and central Kansas late this afternoon and evening, accompanied by some risk for severe hail and wind. ...20z Update... The previous forecast largely remains on track. Latest GOES imagery shows initial thunderstorm development along a weak front across far northwest KS. Ahead of this boundary, modest moisture return across western KS has yielded dewpoints in the upper 50s to low 60s with MLCAPE values increasing to around 1000 J/kg. With temperatures warming into the low 80s, MLCIN is gradually being removed as the front impinges on the returning moisture. Regional VWPs continue to sample 35-40 knot flow at around 4 km AGL, which will support adequate deep-layer shear for organized convection as thunderstorms continue to develop through late afternoon/early evening. Strong/severe thunderstorm coverage remains uncertain with southeastward extent into central KS, but latest observational trends suggest that the severe threat should be relatively greatest across northwest KS through early evening (that said, expected coverage/intensity should remain sufficiently limited to maintain Marginal risk highlights). Elsewhere, the previous forecast (below) remains on track. Instances of sporadic hail and/or wind damage will be possible from eastern AR into northern MS and northwest AL through early evening; however, the convective environment is favorable for mainly short-lived pulse convection (per observed radar trends and regional VWPs), making predictability of any substantial severe threat very limited. ..Moore.. 09/19/2025 .PREV DISCUSSION... /ISSUED 1130 AM CDT Fri Sep 19 2025/ ...Central Plains... Increasing large-scale ascent associated with the embedded shortwave trough and modestly enhanced west-northwesterly jet should influence isolated thunderstorm development by late afternoon/early evening across parts of southwest Nebraska into western Kansas. This region should have a modestly moist low-level airmass in place, with enough daytime heating forecast to support around 1000-1500 J/kg of MLCAPE. Even though mid-level lapse rates are not expected to become overly steep, strong deep-layer shear should aid in convective updraft organization. Any thunderstorms that can form and be sustained could produce isolated severe hail and/or wind gusts as they spread southeastward across western/central Kansas through the evening. ...Midwest/Mississippi Valley... An eastward-moving shortwave trough over the Upper Midwest will more directly influence the middle/upper Mississippi Valley, with moderate destabilization expected this afternoon from the middle Mississippi Valley southward into the Mid-South where MLCAPE will tend to reach 1500-2000 J/kg. Weak deep tropospheric winds will be prevalent along with weak mid-level lapse rates. Even so, some strong to locally severe pulse storms may occur this afternoon through early evening in a broad region spanning parts of Wisconsin/Illinois southward to the Mid-South. ...Western/south-central Minnesota and vicinity... Pending cloud breaks/sufficient heating, scenario may be conducive for funnels and possibly a low chance of a brief tornado in proximity to the upper low and residual surface front, where low-level CAPE/ambient vorticity will be maximized. It is a generally similar regime as to yesterday's reported brief tornado in far southeast North Dakota, although today's setup may be less supportive and more uncertain. ...Southwest States including southeast Arizona... Showers and thunderstorms are ongoing early today across parts of central/eastern Arizona, and on a more isolated basis into western New Mexico and far west Texas. This activity is related to weak ascent aloft associated with minor perturbations rotating through/around a weak upper ridge over the Southwest. Some guidance shows potential for additional robust thunderstorm development by late afternoon/early evening, likely aided by orographic lift and other weak mid-level disturbances. While a localized severe storm or two could occur, substantial uncertainty exists regarding the intensity of these thunderstorms later today owing to ongoing clouds/precipitation, lack of a notable EML, and limited forecast instability. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0243 PM CDT Fri Sep 19 2025 Valid 192000Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF FAR SOUTHERN NEBRASKA INTO NORTHWEST AND CENTRAL KANSAS... ...SUMMARY... Isolated severe thunderstorms may impact parts of far southern Nebraska into northwestern and central Kansas late this afternoon and evening, accompanied by some risk for severe hail and wind. ...20z Update... The previous forecast largely remains on track. Latest GOES imagery shows initial thunderstorm development along a weak front across far northwest KS. Ahead of this boundary, modest moisture return across western KS has yielded dewpoints in the upper 50s to low 60s with MLCAPE values increasing to around 1000 J/kg. With temperatures warming into the low 80s, MLCIN is gradually being removed as the front impinges on the returning moisture. Regional VWPs continue to sample 35-40 knot flow at around 4 km AGL, which will support adequate deep-layer shear for organized convection as thunderstorms continue to develop through late afternoon/early evening. Strong/severe thunderstorm coverage remains uncertain with southeastward extent into central KS, but latest observational trends suggest that the severe threat should be relatively greatest across northwest KS through early evening (that said, expected coverage/intensity should remain sufficiently limited to maintain Marginal risk highlights). Elsewhere, the previous forecast (below) remains on track. Instances of sporadic hail and/or wind damage will be possible from eastern AR into northern MS and northwest AL through early evening; however, the convective environment is favorable for mainly short-lived pulse convection (per observed radar trends and regional VWPs), making predictability of any substantial severe threat very limited. ..Moore.. 09/19/2025 .PREV DISCUSSION... /ISSUED 1130 AM CDT Fri Sep 19 2025/ ...Central Plains... Increasing large-scale ascent associated with the embedded shortwave trough and modestly enhanced west-northwesterly jet should influence isolated thunderstorm development by late afternoon/early evening across parts of southwest Nebraska into western Kansas. This region should have a modestly moist low-level airmass in place, with enough daytime heating forecast to support around 1000-1500 J/kg of MLCAPE. Even though mid-level lapse rates are not expected to become overly steep, strong deep-layer shear should aid in convective updraft organization. Any thunderstorms that can form and be sustained could produce isolated severe hail and/or wind gusts as they spread southeastward across western/central Kansas through the evening. ...Midwest/Mississippi Valley... An eastward-moving shortwave trough over the Upper Midwest will more directly influence the middle/upper Mississippi Valley, with moderate destabilization expected this afternoon from the middle Mississippi Valley southward into the Mid-South where MLCAPE will tend to reach 1500-2000 J/kg. Weak deep tropospheric winds will be prevalent along with weak mid-level lapse rates. Even so, some strong to locally severe pulse storms may occur this afternoon through early evening in a broad region spanning parts of Wisconsin/Illinois southward to the Mid-South. ...Western/south-central Minnesota and vicinity... Pending cloud breaks/sufficient heating, scenario may be conducive for funnels and possibly a low chance of a brief tornado in proximity to the upper low and residual surface front, where low-level CAPE/ambient vorticity will be maximized. It is a generally similar regime as to yesterday's reported brief tornado in far southeast North Dakota, although today's setup may be less supportive and more uncertain. ...Southwest States including southeast Arizona... Showers and thunderstorms are ongoing early today across parts of central/eastern Arizona, and on a more isolated basis into western New Mexico and far west Texas. This activity is related to weak ascent aloft associated with minor perturbations rotating through/around a weak upper ridge over the Southwest. Some guidance shows potential for additional robust thunderstorm development by late afternoon/early evening, likely aided by orographic lift and other weak mid-level disturbances. While a localized severe storm or two could occur, substantial uncertainty exists regarding the intensity of these thunderstorms later today owing to ongoing clouds/precipitation, lack of a notable EML, and limited forecast instability. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0243 PM CDT Fri Sep 19 2025 Valid 192000Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF FAR SOUTHERN NEBRASKA INTO NORTHWEST AND CENTRAL KANSAS... ...SUMMARY... Isolated severe thunderstorms may impact parts of far southern Nebraska into northwestern and central Kansas late this afternoon and evening, accompanied by some risk for severe hail and wind. ...20z Update... The previous forecast largely remains on track. Latest GOES imagery shows initial thunderstorm development along a weak front across far northwest KS. Ahead of this boundary, modest moisture return across western KS has yielded dewpoints in the upper 50s to low 60s with MLCAPE values increasing to around 1000 J/kg. With temperatures warming into the low 80s, MLCIN is gradually being removed as the front impinges on the returning moisture. Regional VWPs continue to sample 35-40 knot flow at around 4 km AGL, which will support adequate deep-layer shear for organized convection as thunderstorms continue to develop through late afternoon/early evening. Strong/severe thunderstorm coverage remains uncertain with southeastward extent into central KS, but latest observational trends suggest that the severe threat should be relatively greatest across northwest KS through early evening (that said, expected coverage/intensity should remain sufficiently limited to maintain Marginal risk highlights). Elsewhere, the previous forecast (below) remains on track. Instances of sporadic hail and/or wind damage will be possible from eastern AR into northern MS and northwest AL through early evening; however, the convective environment is favorable for mainly short-lived pulse convection (per observed radar trends and regional VWPs), making predictability of any substantial severe threat very limited. ..Moore.. 09/19/2025 .PREV DISCUSSION... /ISSUED 1130 AM CDT Fri Sep 19 2025/ ...Central Plains... Increasing large-scale ascent associated with the embedded shortwave trough and modestly enhanced west-northwesterly jet should influence isolated thunderstorm development by late afternoon/early evening across parts of southwest Nebraska into western Kansas. This region should have a modestly moist low-level airmass in place, with enough daytime heating forecast to support around 1000-1500 J/kg of MLCAPE. Even though mid-level lapse rates are not expected to become overly steep, strong deep-layer shear should aid in convective updraft organization. Any thunderstorms that can form and be sustained could produce isolated severe hail and/or wind gusts as they spread southeastward across western/central Kansas through the evening. ...Midwest/Mississippi Valley... An eastward-moving shortwave trough over the Upper Midwest will more directly influence the middle/upper Mississippi Valley, with moderate destabilization expected this afternoon from the middle Mississippi Valley southward into the Mid-South where MLCAPE will tend to reach 1500-2000 J/kg. Weak deep tropospheric winds will be prevalent along with weak mid-level lapse rates. Even so, some strong to locally severe pulse storms may occur this afternoon through early evening in a broad region spanning parts of Wisconsin/Illinois southward to the Mid-South. ...Western/south-central Minnesota and vicinity... Pending cloud breaks/sufficient heating, scenario may be conducive for funnels and possibly a low chance of a brief tornado in proximity to the upper low and residual surface front, where low-level CAPE/ambient vorticity will be maximized. It is a generally similar regime as to yesterday's reported brief tornado in far southeast North Dakota, although today's setup may be less supportive and more uncertain. ...Southwest States including southeast Arizona... Showers and thunderstorms are ongoing early today across parts of central/eastern Arizona, and on a more isolated basis into western New Mexico and far west Texas. This activity is related to weak ascent aloft associated with minor perturbations rotating through/around a weak upper ridge over the Southwest. Some guidance shows potential for additional robust thunderstorm development by late afternoon/early evening, likely aided by orographic lift and other weak mid-level disturbances. While a localized severe storm or two could occur, substantial uncertainty exists regarding the intensity of these thunderstorms later today owing to ongoing clouds/precipitation, lack of a notable EML, and limited forecast instability. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0243 PM CDT Fri Sep 19 2025 Valid 192000Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF FAR SOUTHERN NEBRASKA INTO NORTHWEST AND CENTRAL KANSAS... ...SUMMARY... Isolated severe thunderstorms may impact parts of far southern Nebraska into northwestern and central Kansas late this afternoon and evening, accompanied by some risk for severe hail and wind. ...20z Update... The previous forecast largely remains on track. Latest GOES imagery shows initial thunderstorm development along a weak front across far northwest KS. Ahead of this boundary, modest moisture return across western KS has yielded dewpoints in the upper 50s to low 60s with MLCAPE values increasing to around 1000 J/kg. With temperatures warming into the low 80s, MLCIN is gradually being removed as the front impinges on the returning moisture. Regional VWPs continue to sample 35-40 knot flow at around 4 km AGL, which will support adequate deep-layer shear for organized convection as thunderstorms continue to develop through late afternoon/early evening. Strong/severe thunderstorm coverage remains uncertain with southeastward extent into central KS, but latest observational trends suggest that the severe threat should be relatively greatest across northwest KS through early evening (that said, expected coverage/intensity should remain sufficiently limited to maintain Marginal risk highlights). Elsewhere, the previous forecast (below) remains on track. Instances of sporadic hail and/or wind damage will be possible from eastern AR into northern MS and northwest AL through early evening; however, the convective environment is favorable for mainly short-lived pulse convection (per observed radar trends and regional VWPs), making predictability of any substantial severe threat very limited. ..Moore.. 09/19/2025 .PREV DISCUSSION... /ISSUED 1130 AM CDT Fri Sep 19 2025/ ...Central Plains... Increasing large-scale ascent associated with the embedded shortwave trough and modestly enhanced west-northwesterly jet should influence isolated thunderstorm development by late afternoon/early evening across parts of southwest Nebraska into western Kansas. This region should have a modestly moist low-level airmass in place, with enough daytime heating forecast to support around 1000-1500 J/kg of MLCAPE. Even though mid-level lapse rates are not expected to become overly steep, strong deep-layer shear should aid in convective updraft organization. Any thunderstorms that can form and be sustained could produce isolated severe hail and/or wind gusts as they spread southeastward across western/central Kansas through the evening. ...Midwest/Mississippi Valley... An eastward-moving shortwave trough over the Upper Midwest will more directly influence the middle/upper Mississippi Valley, with moderate destabilization expected this afternoon from the middle Mississippi Valley southward into the Mid-South where MLCAPE will tend to reach 1500-2000 J/kg. Weak deep tropospheric winds will be prevalent along with weak mid-level lapse rates. Even so, some strong to locally severe pulse storms may occur this afternoon through early evening in a broad region spanning parts of Wisconsin/Illinois southward to the Mid-South. ...Western/south-central Minnesota and vicinity... Pending cloud breaks/sufficient heating, scenario may be conducive for funnels and possibly a low chance of a brief tornado in proximity to the upper low and residual surface front, where low-level CAPE/ambient vorticity will be maximized. It is a generally similar regime as to yesterday's reported brief tornado in far southeast North Dakota, although today's setup may be less supportive and more uncertain. ...Southwest States including southeast Arizona... Showers and thunderstorms are ongoing early today across parts of central/eastern Arizona, and on a more isolated basis into western New Mexico and far west Texas. This activity is related to weak ascent aloft associated with minor perturbations rotating through/around a weak upper ridge over the Southwest. Some guidance shows potential for additional robust thunderstorm development by late afternoon/early evening, likely aided by orographic lift and other weak mid-level disturbances. While a localized severe storm or two could occur, substantial uncertainty exists regarding the intensity of these thunderstorms later today owing to ongoing clouds/precipitation, lack of a notable EML, and limited forecast instability. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0243 PM CDT Fri Sep 19 2025 Valid 192000Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF FAR SOUTHERN NEBRASKA INTO NORTHWEST AND CENTRAL KANSAS... ...SUMMARY... Isolated severe thunderstorms may impact parts of far southern Nebraska into northwestern and central Kansas late this afternoon and evening, accompanied by some risk for severe hail and wind. ...20z Update... The previous forecast largely remains on track. Latest GOES imagery shows initial thunderstorm development along a weak front across far northwest KS. Ahead of this boundary, modest moisture return across western KS has yielded dewpoints in the upper 50s to low 60s with MLCAPE values increasing to around 1000 J/kg. With temperatures warming into the low 80s, MLCIN is gradually being removed as the front impinges on the returning moisture. Regional VWPs continue to sample 35-40 knot flow at around 4 km AGL, which will support adequate deep-layer shear for organized convection as thunderstorms continue to develop through late afternoon/early evening. Strong/severe thunderstorm coverage remains uncertain with southeastward extent into central KS, but latest observational trends suggest that the severe threat should be relatively greatest across northwest KS through early evening (that said, expected coverage/intensity should remain sufficiently limited to maintain Marginal risk highlights). Elsewhere, the previous forecast (below) remains on track. Instances of sporadic hail and/or wind damage will be possible from eastern AR into northern MS and northwest AL through early evening; however, the convective environment is favorable for mainly short-lived pulse convection (per observed radar trends and regional VWPs), making predictability of any substantial severe threat very limited. ..Moore.. 09/19/2025 .PREV DISCUSSION... /ISSUED 1130 AM CDT Fri Sep 19 2025/ ...Central Plains... Increasing large-scale ascent associated with the embedded shortwave trough and modestly enhanced west-northwesterly jet should influence isolated thunderstorm development by late afternoon/early evening across parts of southwest Nebraska into western Kansas. This region should have a modestly moist low-level airmass in place, with enough daytime heating forecast to support around 1000-1500 J/kg of MLCAPE. Even though mid-level lapse rates are not expected to become overly steep, strong deep-layer shear should aid in convective updraft organization. Any thunderstorms that can form and be sustained could produce isolated severe hail and/or wind gusts as they spread southeastward across western/central Kansas through the evening. ...Midwest/Mississippi Valley... An eastward-moving shortwave trough over the Upper Midwest will more directly influence the middle/upper Mississippi Valley, with moderate destabilization expected this afternoon from the middle Mississippi Valley southward into the Mid-South where MLCAPE will tend to reach 1500-2000 J/kg. Weak deep tropospheric winds will be prevalent along with weak mid-level lapse rates. Even so, some strong to locally severe pulse storms may occur this afternoon through early evening in a broad region spanning parts of Wisconsin/Illinois southward to the Mid-South. ...Western/south-central Minnesota and vicinity... Pending cloud breaks/sufficient heating, scenario may be conducive for funnels and possibly a low chance of a brief tornado in proximity to the upper low and residual surface front, where low-level CAPE/ambient vorticity will be maximized. It is a generally similar regime as to yesterday's reported brief tornado in far southeast North Dakota, although today's setup may be less supportive and more uncertain. ...Southwest States including southeast Arizona... Showers and thunderstorms are ongoing early today across parts of central/eastern Arizona, and on a more isolated basis into western New Mexico and far west Texas. This activity is related to weak ascent aloft associated with minor perturbations rotating through/around a weak upper ridge over the Southwest. Some guidance shows potential for additional robust thunderstorm development by late afternoon/early evening, likely aided by orographic lift and other weak mid-level disturbances. While a localized severe storm or two could occur, substantial uncertainty exists regarding the intensity of these thunderstorms later today owing to ongoing clouds/precipitation, lack of a notable EML, and limited forecast instability. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0243 PM CDT Fri Sep 19 2025 Valid 192000Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF FAR SOUTHERN NEBRASKA INTO NORTHWEST AND CENTRAL KANSAS... ...SUMMARY... Isolated severe thunderstorms may impact parts of far southern Nebraska into northwestern and central Kansas late this afternoon and evening, accompanied by some risk for severe hail and wind. ...20z Update... The previous forecast largely remains on track. Latest GOES imagery shows initial thunderstorm development along a weak front across far northwest KS. Ahead of this boundary, modest moisture return across western KS has yielded dewpoints in the upper 50s to low 60s with MLCAPE values increasing to around 1000 J/kg. With temperatures warming into the low 80s, MLCIN is gradually being removed as the front impinges on the returning moisture. Regional VWPs continue to sample 35-40 knot flow at around 4 km AGL, which will support adequate deep-layer shear for organized convection as thunderstorms continue to develop through late afternoon/early evening. Strong/severe thunderstorm coverage remains uncertain with southeastward extent into central KS, but latest observational trends suggest that the severe threat should be relatively greatest across northwest KS through early evening (that said, expected coverage/intensity should remain sufficiently limited to maintain Marginal risk highlights). Elsewhere, the previous forecast (below) remains on track. Instances of sporadic hail and/or wind damage will be possible from eastern AR into northern MS and northwest AL through early evening; however, the convective environment is favorable for mainly short-lived pulse convection (per observed radar trends and regional VWPs), making predictability of any substantial severe threat very limited. ..Moore.. 09/19/2025 .PREV DISCUSSION... /ISSUED 1130 AM CDT Fri Sep 19 2025/ ...Central Plains... Increasing large-scale ascent associated with the embedded shortwave trough and modestly enhanced west-northwesterly jet should influence isolated thunderstorm development by late afternoon/early evening across parts of southwest Nebraska into western Kansas. This region should have a modestly moist low-level airmass in place, with enough daytime heating forecast to support around 1000-1500 J/kg of MLCAPE. Even though mid-level lapse rates are not expected to become overly steep, strong deep-layer shear should aid in convective updraft organization. Any thunderstorms that can form and be sustained could produce isolated severe hail and/or wind gusts as they spread southeastward across western/central Kansas through the evening. ...Midwest/Mississippi Valley... An eastward-moving shortwave trough over the Upper Midwest will more directly influence the middle/upper Mississippi Valley, with moderate destabilization expected this afternoon from the middle Mississippi Valley southward into the Mid-South where MLCAPE will tend to reach 1500-2000 J/kg. Weak deep tropospheric winds will be prevalent along with weak mid-level lapse rates. Even so, some strong to locally severe pulse storms may occur this afternoon through early evening in a broad region spanning parts of Wisconsin/Illinois southward to the Mid-South. ...Western/south-central Minnesota and vicinity... Pending cloud breaks/sufficient heating, scenario may be conducive for funnels and possibly a low chance of a brief tornado in proximity to the upper low and residual surface front, where low-level CAPE/ambient vorticity will be maximized. It is a generally similar regime as to yesterday's reported brief tornado in far southeast North Dakota, although today's setup may be less supportive and more uncertain. ...Southwest States including southeast Arizona... Showers and thunderstorms are ongoing early today across parts of central/eastern Arizona, and on a more isolated basis into western New Mexico and far west Texas. This activity is related to weak ascent aloft associated with minor perturbations rotating through/around a weak upper ridge over the Southwest. Some guidance shows potential for additional robust thunderstorm development by late afternoon/early evening, likely aided by orographic lift and other weak mid-level disturbances. While a localized severe storm or two could occur, substantial uncertainty exists regarding the intensity of these thunderstorms later today owing to ongoing clouds/precipitation, lack of a notable EML, and limited forecast instability. Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0227 PM CDT Fri Sep 19 2025 Valid 211200Z - 221200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A few strong thunderstorms are possible across parts of the Great Plains and the Ohio Valley on Sunday, though organized severe thunderstorm potential remains uncertain. ...Discussion... A compact midlevel trough will advance eastward across the Upper Midwest on Sunday, while a broader large-scale trough encompasses much of the central CONUS. Several embedded shortwave impulses (some convectively induced/enhanced) will track eastward within the zonal midlevel flow across parts of the Ohio Valley, central Plains and northern Plains through the period. Given the low-amplitude nature of these impulses (and large differences in timing/evolution among model guidance), organized severe thunderstorm potential remains uncertain at this time. Nevertheless, a moist/moderately unstable air mass will be in place from the southern/central Plains eastward into parts of the OH Valley, and given the subtle areas of large-scale lift and locally enhanced midlevel flow, a broad area of strong-thunderstorm potential is evident. As the details regarding timing/evolution of the embedded shortwave troughs and related destabilization become clearer, one or more Marginal Risk areas may be warranted over the central/southern Plains and the Ohio Valley. ..Weinman.. 09/19/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0227 PM CDT Fri Sep 19 2025 Valid 211200Z - 221200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A few strong thunderstorms are possible across parts of the Great Plains and the Ohio Valley on Sunday, though organized severe thunderstorm potential remains uncertain. ...Discussion... A compact midlevel trough will advance eastward across the Upper Midwest on Sunday, while a broader large-scale trough encompasses much of the central CONUS. Several embedded shortwave impulses (some convectively induced/enhanced) will track eastward within the zonal midlevel flow across parts of the Ohio Valley, central Plains and northern Plains through the period. Given the low-amplitude nature of these impulses (and large differences in timing/evolution among model guidance), organized severe thunderstorm potential remains uncertain at this time. Nevertheless, a moist/moderately unstable air mass will be in place from the southern/central Plains eastward into parts of the OH Valley, and given the subtle areas of large-scale lift and locally enhanced midlevel flow, a broad area of strong-thunderstorm potential is evident. As the details regarding timing/evolution of the embedded shortwave troughs and related destabilization become clearer, one or more Marginal Risk areas may be warranted over the central/southern Plains and the Ohio Valley. ..Weinman.. 09/19/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0227 PM CDT Fri Sep 19 2025 Valid 211200Z - 221200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A few strong thunderstorms are possible across parts of the Great Plains and the Ohio Valley on Sunday, though organized severe thunderstorm potential remains uncertain. ...Discussion... A compact midlevel trough will advance eastward across the Upper Midwest on Sunday, while a broader large-scale trough encompasses much of the central CONUS. Several embedded shortwave impulses (some convectively induced/enhanced) will track eastward within the zonal midlevel flow across parts of the Ohio Valley, central Plains and northern Plains through the period. Given the low-amplitude nature of these impulses (and large differences in timing/evolution among model guidance), organized severe thunderstorm potential remains uncertain at this time. Nevertheless, a moist/moderately unstable air mass will be in place from the southern/central Plains eastward into parts of the OH Valley, and given the subtle areas of large-scale lift and locally enhanced midlevel flow, a broad area of strong-thunderstorm potential is evident. As the details regarding timing/evolution of the embedded shortwave troughs and related destabilization become clearer, one or more Marginal Risk areas may be warranted over the central/southern Plains and the Ohio Valley. ..Weinman.. 09/19/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0227 PM CDT Fri Sep 19 2025 Valid 211200Z - 221200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A few strong thunderstorms are possible across parts of the Great Plains and the Ohio Valley on Sunday, though organized severe thunderstorm potential remains uncertain. ...Discussion... A compact midlevel trough will advance eastward across the Upper Midwest on Sunday, while a broader large-scale trough encompasses much of the central CONUS. Several embedded shortwave impulses (some convectively induced/enhanced) will track eastward within the zonal midlevel flow across parts of the Ohio Valley, central Plains and northern Plains through the period. Given the low-amplitude nature of these impulses (and large differences in timing/evolution among model guidance), organized severe thunderstorm potential remains uncertain at this time. Nevertheless, a moist/moderately unstable air mass will be in place from the southern/central Plains eastward into parts of the OH Valley, and given the subtle areas of large-scale lift and locally enhanced midlevel flow, a broad area of strong-thunderstorm potential is evident. As the details regarding timing/evolution of the embedded shortwave troughs and related destabilization become clearer, one or more Marginal Risk areas may be warranted over the central/southern Plains and the Ohio Valley. ..Weinman.. 09/19/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0227 PM CDT Fri Sep 19 2025 Valid 211200Z - 221200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A few strong thunderstorms are possible across parts of the Great Plains and the Ohio Valley on Sunday, though organized severe thunderstorm potential remains uncertain. ...Discussion... A compact midlevel trough will advance eastward across the Upper Midwest on Sunday, while a broader large-scale trough encompasses much of the central CONUS. Several embedded shortwave impulses (some convectively induced/enhanced) will track eastward within the zonal midlevel flow across parts of the Ohio Valley, central Plains and northern Plains through the period. Given the low-amplitude nature of these impulses (and large differences in timing/evolution among model guidance), organized severe thunderstorm potential remains uncertain at this time. Nevertheless, a moist/moderately unstable air mass will be in place from the southern/central Plains eastward into parts of the OH Valley, and given the subtle areas of large-scale lift and locally enhanced midlevel flow, a broad area of strong-thunderstorm potential is evident. As the details regarding timing/evolution of the embedded shortwave troughs and related destabilization become clearer, one or more Marginal Risk areas may be warranted over the central/southern Plains and the Ohio Valley. ..Weinman.. 09/19/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0227 PM CDT Fri Sep 19 2025 Valid 211200Z - 221200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A few strong thunderstorms are possible across parts of the Great Plains and the Ohio Valley on Sunday, though organized severe thunderstorm potential remains uncertain. ...Discussion... A compact midlevel trough will advance eastward across the Upper Midwest on Sunday, while a broader large-scale trough encompasses much of the central CONUS. Several embedded shortwave impulses (some convectively induced/enhanced) will track eastward within the zonal midlevel flow across parts of the Ohio Valley, central Plains and northern Plains through the period. Given the low-amplitude nature of these impulses (and large differences in timing/evolution among model guidance), organized severe thunderstorm potential remains uncertain at this time. Nevertheless, a moist/moderately unstable air mass will be in place from the southern/central Plains eastward into parts of the OH Valley, and given the subtle areas of large-scale lift and locally enhanced midlevel flow, a broad area of strong-thunderstorm potential is evident. As the details regarding timing/evolution of the embedded shortwave troughs and related destabilization become clearer, one or more Marginal Risk areas may be warranted over the central/southern Plains and the Ohio Valley. ..Weinman.. 09/19/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0227 PM CDT Fri Sep 19 2025 Valid 211200Z - 221200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A few strong thunderstorms are possible across parts of the Great Plains and the Ohio Valley on Sunday, though organized severe thunderstorm potential remains uncertain. ...Discussion... A compact midlevel trough will advance eastward across the Upper Midwest on Sunday, while a broader large-scale trough encompasses much of the central CONUS. Several embedded shortwave impulses (some convectively induced/enhanced) will track eastward within the zonal midlevel flow across parts of the Ohio Valley, central Plains and northern Plains through the period. Given the low-amplitude nature of these impulses (and large differences in timing/evolution among model guidance), organized severe thunderstorm potential remains uncertain at this time. Nevertheless, a moist/moderately unstable air mass will be in place from the southern/central Plains eastward into parts of the OH Valley, and given the subtle areas of large-scale lift and locally enhanced midlevel flow, a broad area of strong-thunderstorm potential is evident. As the details regarding timing/evolution of the embedded shortwave troughs and related destabilization become clearer, one or more Marginal Risk areas may be warranted over the central/southern Plains and the Ohio Valley. ..Weinman.. 09/19/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0227 PM CDT Fri Sep 19 2025 Valid 211200Z - 221200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A few strong thunderstorms are possible across parts of the Great Plains and the Ohio Valley on Sunday, though organized severe thunderstorm potential remains uncertain. ...Discussion... A compact midlevel trough will advance eastward across the Upper Midwest on Sunday, while a broader large-scale trough encompasses much of the central CONUS. Several embedded shortwave impulses (some convectively induced/enhanced) will track eastward within the zonal midlevel flow across parts of the Ohio Valley, central Plains and northern Plains through the period. Given the low-amplitude nature of these impulses (and large differences in timing/evolution among model guidance), organized severe thunderstorm potential remains uncertain at this time. Nevertheless, a moist/moderately unstable air mass will be in place from the southern/central Plains eastward into parts of the OH Valley, and given the subtle areas of large-scale lift and locally enhanced midlevel flow, a broad area of strong-thunderstorm potential is evident. As the details regarding timing/evolution of the embedded shortwave troughs and related destabilization become clearer, one or more Marginal Risk areas may be warranted over the central/southern Plains and the Ohio Valley. ..Weinman.. 09/19/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0227 PM CDT Fri Sep 19 2025 Valid 211200Z - 221200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A few strong thunderstorms are possible across parts of the Great Plains and the Ohio Valley on Sunday, though organized severe thunderstorm potential remains uncertain. ...Discussion... A compact midlevel trough will advance eastward across the Upper Midwest on Sunday, while a broader large-scale trough encompasses much of the central CONUS. Several embedded shortwave impulses (some convectively induced/enhanced) will track eastward within the zonal midlevel flow across parts of the Ohio Valley, central Plains and northern Plains through the period. Given the low-amplitude nature of these impulses (and large differences in timing/evolution among model guidance), organized severe thunderstorm potential remains uncertain at this time. Nevertheless, a moist/moderately unstable air mass will be in place from the southern/central Plains eastward into parts of the OH Valley, and given the subtle areas of large-scale lift and locally enhanced midlevel flow, a broad area of strong-thunderstorm potential is evident. As the details regarding timing/evolution of the embedded shortwave troughs and related destabilization become clearer, one or more Marginal Risk areas may be warranted over the central/southern Plains and the Ohio Valley. ..Weinman.. 09/19/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 PM CDT Fri Sep 19 2025 Valid 201200Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not currently expected on Saturday. ...Discussion... A midlevel shortwave trough will move gradually eastward across the Upper Midwest through the forecast period, while being reinforced by an upstream midlevel impulse moving southeastward from the northern Plains into the base of the trough. While midlevel flow accompanying the trough will be modest, a broad area of DCVA will promote scattered thunderstorms from WI southward toward the Lower OH Valley. While locally strong gusts cannot be ruled out where PBL lapse rates diurnally steepen in cloud breaks, poor midlevel lapse rates (and marginal buoyancy) should limit the severe risk -- especially given modest deep-layer flow/shear. Farther south, a warm/moist air mass will be in place along/immediately south of a quasi-stationary surface boundary draped across southern/central KS. In the wake of an overnight convective cluster moving eastward out of southeastern KS/northeastern OK, weak low-level warm advection atop the residual outflow and quasi-stationary front should promote afternoon thunderstorms -- focused across northern OK into far southern KS. Modestly enhanced midlevel west-northwesterly flow (closer to the midlevel trough) will conditionally support a couple strong storms over northeastern OK, though uncertainty regarding PBL recovery behind morning convection limits confidence in the risk at this time. If confidence in PBL recovery increases, a Marginal Risk could be warranted here. Steep lapse rates and ample buoyancy across north-central into northwest OK may also promote a couple strong storms, but weak deep-layer flow/shear should limit the risk of organized storms. ..Weinman.. 09/19/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 PM CDT Fri Sep 19 2025 Valid 201200Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not currently expected on Saturday. ...Discussion... A midlevel shortwave trough will move gradually eastward across the Upper Midwest through the forecast period, while being reinforced by an upstream midlevel impulse moving southeastward from the northern Plains into the base of the trough. While midlevel flow accompanying the trough will be modest, a broad area of DCVA will promote scattered thunderstorms from WI southward toward the Lower OH Valley. While locally strong gusts cannot be ruled out where PBL lapse rates diurnally steepen in cloud breaks, poor midlevel lapse rates (and marginal buoyancy) should limit the severe risk -- especially given modest deep-layer flow/shear. Farther south, a warm/moist air mass will be in place along/immediately south of a quasi-stationary surface boundary draped across southern/central KS. In the wake of an overnight convective cluster moving eastward out of southeastern KS/northeastern OK, weak low-level warm advection atop the residual outflow and quasi-stationary front should promote afternoon thunderstorms -- focused across northern OK into far southern KS. Modestly enhanced midlevel west-northwesterly flow (closer to the midlevel trough) will conditionally support a couple strong storms over northeastern OK, though uncertainty regarding PBL recovery behind morning convection limits confidence in the risk at this time. If confidence in PBL recovery increases, a Marginal Risk could be warranted here. Steep lapse rates and ample buoyancy across north-central into northwest OK may also promote a couple strong storms, but weak deep-layer flow/shear should limit the risk of organized storms. ..Weinman.. 09/19/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 PM CDT Fri Sep 19 2025 Valid 201200Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not currently expected on Saturday. ...Discussion... A midlevel shortwave trough will move gradually eastward across the Upper Midwest through the forecast period, while being reinforced by an upstream midlevel impulse moving southeastward from the northern Plains into the base of the trough. While midlevel flow accompanying the trough will be modest, a broad area of DCVA will promote scattered thunderstorms from WI southward toward the Lower OH Valley. While locally strong gusts cannot be ruled out where PBL lapse rates diurnally steepen in cloud breaks, poor midlevel lapse rates (and marginal buoyancy) should limit the severe risk -- especially given modest deep-layer flow/shear. Farther south, a warm/moist air mass will be in place along/immediately south of a quasi-stationary surface boundary draped across southern/central KS. In the wake of an overnight convective cluster moving eastward out of southeastern KS/northeastern OK, weak low-level warm advection atop the residual outflow and quasi-stationary front should promote afternoon thunderstorms -- focused across northern OK into far southern KS. Modestly enhanced midlevel west-northwesterly flow (closer to the midlevel trough) will conditionally support a couple strong storms over northeastern OK, though uncertainty regarding PBL recovery behind morning convection limits confidence in the risk at this time. If confidence in PBL recovery increases, a Marginal Risk could be warranted here. Steep lapse rates and ample buoyancy across north-central into northwest OK may also promote a couple strong storms, but weak deep-layer flow/shear should limit the risk of organized storms. ..Weinman.. 09/19/2025 Read more