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SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0220 PM CDT Thu Sep 18 2025 Valid 201200Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not currently expected on Saturday. ...Synopsis... A broad mid/upper-level trough will remain across parts of the central CONUS on Saturday, as multiple embedded shortwaves traverse parts of the northern Plains and Upper Midwest. Farther west, a mid/upper-level trough offshore of southern CA is forecast to move slowly eastward, while a stronger mid/upper-level shortwave trough will approach the Pacific Northwest later in the period. The broadly cyclonic flow regime will support thunderstorm potential across a large part of the CONUS, though generally weak deep-layer shear should tend to limit the organized severe threat. Scattered storms will again be possible across the Upper Midwest/Great Lakes, where relatively cool temperatures aloft could support a few strong storms. Morning convection is expected across parts of KS, with redevelopment possible during the afternoon from parts of OK/KS into the mid MS Valley. Depending on the extent of heating/destabilization, strong storms will be possible during the afternoon/evening across this region, though potential for a corridor of more organized severe threat is quite uncertain at this time. Isolated strong storms will also be possible in the CO Front Range vicinity, where somewhat more favorable deep-layer shear may be in place, but it remains uncertain if destabilization will be sufficient to support a severe-hail threat. ..Dean.. 09/18/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0220 PM CDT Thu Sep 18 2025 Valid 201200Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not currently expected on Saturday. ...Synopsis... A broad mid/upper-level trough will remain across parts of the central CONUS on Saturday, as multiple embedded shortwaves traverse parts of the northern Plains and Upper Midwest. Farther west, a mid/upper-level trough offshore of southern CA is forecast to move slowly eastward, while a stronger mid/upper-level shortwave trough will approach the Pacific Northwest later in the period. The broadly cyclonic flow regime will support thunderstorm potential across a large part of the CONUS, though generally weak deep-layer shear should tend to limit the organized severe threat. Scattered storms will again be possible across the Upper Midwest/Great Lakes, where relatively cool temperatures aloft could support a few strong storms. Morning convection is expected across parts of KS, with redevelopment possible during the afternoon from parts of OK/KS into the mid MS Valley. Depending on the extent of heating/destabilization, strong storms will be possible during the afternoon/evening across this region, though potential for a corridor of more organized severe threat is quite uncertain at this time. Isolated strong storms will also be possible in the CO Front Range vicinity, where somewhat more favorable deep-layer shear may be in place, but it remains uncertain if destabilization will be sufficient to support a severe-hail threat. ..Dean.. 09/18/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0220 PM CDT Thu Sep 18 2025 Valid 201200Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not currently expected on Saturday. ...Synopsis... A broad mid/upper-level trough will remain across parts of the central CONUS on Saturday, as multiple embedded shortwaves traverse parts of the northern Plains and Upper Midwest. Farther west, a mid/upper-level trough offshore of southern CA is forecast to move slowly eastward, while a stronger mid/upper-level shortwave trough will approach the Pacific Northwest later in the period. The broadly cyclonic flow regime will support thunderstorm potential across a large part of the CONUS, though generally weak deep-layer shear should tend to limit the organized severe threat. Scattered storms will again be possible across the Upper Midwest/Great Lakes, where relatively cool temperatures aloft could support a few strong storms. Morning convection is expected across parts of KS, with redevelopment possible during the afternoon from parts of OK/KS into the mid MS Valley. Depending on the extent of heating/destabilization, strong storms will be possible during the afternoon/evening across this region, though potential for a corridor of more organized severe threat is quite uncertain at this time. Isolated strong storms will also be possible in the CO Front Range vicinity, where somewhat more favorable deep-layer shear may be in place, but it remains uncertain if destabilization will be sufficient to support a severe-hail threat. ..Dean.. 09/18/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0220 PM CDT Thu Sep 18 2025 Valid 201200Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not currently expected on Saturday. ...Synopsis... A broad mid/upper-level trough will remain across parts of the central CONUS on Saturday, as multiple embedded shortwaves traverse parts of the northern Plains and Upper Midwest. Farther west, a mid/upper-level trough offshore of southern CA is forecast to move slowly eastward, while a stronger mid/upper-level shortwave trough will approach the Pacific Northwest later in the period. The broadly cyclonic flow regime will support thunderstorm potential across a large part of the CONUS, though generally weak deep-layer shear should tend to limit the organized severe threat. Scattered storms will again be possible across the Upper Midwest/Great Lakes, where relatively cool temperatures aloft could support a few strong storms. Morning convection is expected across parts of KS, with redevelopment possible during the afternoon from parts of OK/KS into the mid MS Valley. Depending on the extent of heating/destabilization, strong storms will be possible during the afternoon/evening across this region, though potential for a corridor of more organized severe threat is quite uncertain at this time. Isolated strong storms will also be possible in the CO Front Range vicinity, where somewhat more favorable deep-layer shear may be in place, but it remains uncertain if destabilization will be sufficient to support a severe-hail threat. ..Dean.. 09/18/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0220 PM CDT Thu Sep 18 2025 Valid 201200Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not currently expected on Saturday. ...Synopsis... A broad mid/upper-level trough will remain across parts of the central CONUS on Saturday, as multiple embedded shortwaves traverse parts of the northern Plains and Upper Midwest. Farther west, a mid/upper-level trough offshore of southern CA is forecast to move slowly eastward, while a stronger mid/upper-level shortwave trough will approach the Pacific Northwest later in the period. The broadly cyclonic flow regime will support thunderstorm potential across a large part of the CONUS, though generally weak deep-layer shear should tend to limit the organized severe threat. Scattered storms will again be possible across the Upper Midwest/Great Lakes, where relatively cool temperatures aloft could support a few strong storms. Morning convection is expected across parts of KS, with redevelopment possible during the afternoon from parts of OK/KS into the mid MS Valley. Depending on the extent of heating/destabilization, strong storms will be possible during the afternoon/evening across this region, though potential for a corridor of more organized severe threat is quite uncertain at this time. Isolated strong storms will also be possible in the CO Front Range vicinity, where somewhat more favorable deep-layer shear may be in place, but it remains uncertain if destabilization will be sufficient to support a severe-hail threat. ..Dean.. 09/18/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0220 PM CDT Thu Sep 18 2025 Valid 201200Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not currently expected on Saturday. ...Synopsis... A broad mid/upper-level trough will remain across parts of the central CONUS on Saturday, as multiple embedded shortwaves traverse parts of the northern Plains and Upper Midwest. Farther west, a mid/upper-level trough offshore of southern CA is forecast to move slowly eastward, while a stronger mid/upper-level shortwave trough will approach the Pacific Northwest later in the period. The broadly cyclonic flow regime will support thunderstorm potential across a large part of the CONUS, though generally weak deep-layer shear should tend to limit the organized severe threat. Scattered storms will again be possible across the Upper Midwest/Great Lakes, where relatively cool temperatures aloft could support a few strong storms. Morning convection is expected across parts of KS, with redevelopment possible during the afternoon from parts of OK/KS into the mid MS Valley. Depending on the extent of heating/destabilization, strong storms will be possible during the afternoon/evening across this region, though potential for a corridor of more organized severe threat is quite uncertain at this time. Isolated strong storms will also be possible in the CO Front Range vicinity, where somewhat more favorable deep-layer shear may be in place, but it remains uncertain if destabilization will be sufficient to support a severe-hail threat. ..Dean.. 09/18/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0220 PM CDT Thu Sep 18 2025 Valid 201200Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not currently expected on Saturday. ...Synopsis... A broad mid/upper-level trough will remain across parts of the central CONUS on Saturday, as multiple embedded shortwaves traverse parts of the northern Plains and Upper Midwest. Farther west, a mid/upper-level trough offshore of southern CA is forecast to move slowly eastward, while a stronger mid/upper-level shortwave trough will approach the Pacific Northwest later in the period. The broadly cyclonic flow regime will support thunderstorm potential across a large part of the CONUS, though generally weak deep-layer shear should tend to limit the organized severe threat. Scattered storms will again be possible across the Upper Midwest/Great Lakes, where relatively cool temperatures aloft could support a few strong storms. Morning convection is expected across parts of KS, with redevelopment possible during the afternoon from parts of OK/KS into the mid MS Valley. Depending on the extent of heating/destabilization, strong storms will be possible during the afternoon/evening across this region, though potential for a corridor of more organized severe threat is quite uncertain at this time. Isolated strong storms will also be possible in the CO Front Range vicinity, where somewhat more favorable deep-layer shear may be in place, but it remains uncertain if destabilization will be sufficient to support a severe-hail threat. ..Dean.. 09/18/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0220 PM CDT Thu Sep 18 2025 Valid 201200Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not currently expected on Saturday. ...Synopsis... A broad mid/upper-level trough will remain across parts of the central CONUS on Saturday, as multiple embedded shortwaves traverse parts of the northern Plains and Upper Midwest. Farther west, a mid/upper-level trough offshore of southern CA is forecast to move slowly eastward, while a stronger mid/upper-level shortwave trough will approach the Pacific Northwest later in the period. The broadly cyclonic flow regime will support thunderstorm potential across a large part of the CONUS, though generally weak deep-layer shear should tend to limit the organized severe threat. Scattered storms will again be possible across the Upper Midwest/Great Lakes, where relatively cool temperatures aloft could support a few strong storms. Morning convection is expected across parts of KS, with redevelopment possible during the afternoon from parts of OK/KS into the mid MS Valley. Depending on the extent of heating/destabilization, strong storms will be possible during the afternoon/evening across this region, though potential for a corridor of more organized severe threat is quite uncertain at this time. Isolated strong storms will also be possible in the CO Front Range vicinity, where somewhat more favorable deep-layer shear may be in place, but it remains uncertain if destabilization will be sufficient to support a severe-hail threat. ..Dean.. 09/18/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0220 PM CDT Thu Sep 18 2025 Valid 201200Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not currently expected on Saturday. ...Synopsis... A broad mid/upper-level trough will remain across parts of the central CONUS on Saturday, as multiple embedded shortwaves traverse parts of the northern Plains and Upper Midwest. Farther west, a mid/upper-level trough offshore of southern CA is forecast to move slowly eastward, while a stronger mid/upper-level shortwave trough will approach the Pacific Northwest later in the period. The broadly cyclonic flow regime will support thunderstorm potential across a large part of the CONUS, though generally weak deep-layer shear should tend to limit the organized severe threat. Scattered storms will again be possible across the Upper Midwest/Great Lakes, where relatively cool temperatures aloft could support a few strong storms. Morning convection is expected across parts of KS, with redevelopment possible during the afternoon from parts of OK/KS into the mid MS Valley. Depending on the extent of heating/destabilization, strong storms will be possible during the afternoon/evening across this region, though potential for a corridor of more organized severe threat is quite uncertain at this time. Isolated strong storms will also be possible in the CO Front Range vicinity, where somewhat more favorable deep-layer shear may be in place, but it remains uncertain if destabilization will be sufficient to support a severe-hail threat. ..Dean.. 09/18/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0220 PM CDT Thu Sep 18 2025 Valid 201200Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not currently expected on Saturday. ...Synopsis... A broad mid/upper-level trough will remain across parts of the central CONUS on Saturday, as multiple embedded shortwaves traverse parts of the northern Plains and Upper Midwest. Farther west, a mid/upper-level trough offshore of southern CA is forecast to move slowly eastward, while a stronger mid/upper-level shortwave trough will approach the Pacific Northwest later in the period. The broadly cyclonic flow regime will support thunderstorm potential across a large part of the CONUS, though generally weak deep-layer shear should tend to limit the organized severe threat. Scattered storms will again be possible across the Upper Midwest/Great Lakes, where relatively cool temperatures aloft could support a few strong storms. Morning convection is expected across parts of KS, with redevelopment possible during the afternoon from parts of OK/KS into the mid MS Valley. Depending on the extent of heating/destabilization, strong storms will be possible during the afternoon/evening across this region, though potential for a corridor of more organized severe threat is quite uncertain at this time. Isolated strong storms will also be possible in the CO Front Range vicinity, where somewhat more favorable deep-layer shear may be in place, but it remains uncertain if destabilization will be sufficient to support a severe-hail threat. ..Dean.. 09/18/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0220 PM CDT Thu Sep 18 2025 Valid 201200Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not currently expected on Saturday. ...Synopsis... A broad mid/upper-level trough will remain across parts of the central CONUS on Saturday, as multiple embedded shortwaves traverse parts of the northern Plains and Upper Midwest. Farther west, a mid/upper-level trough offshore of southern CA is forecast to move slowly eastward, while a stronger mid/upper-level shortwave trough will approach the Pacific Northwest later in the period. The broadly cyclonic flow regime will support thunderstorm potential across a large part of the CONUS, though generally weak deep-layer shear should tend to limit the organized severe threat. Scattered storms will again be possible across the Upper Midwest/Great Lakes, where relatively cool temperatures aloft could support a few strong storms. Morning convection is expected across parts of KS, with redevelopment possible during the afternoon from parts of OK/KS into the mid MS Valley. Depending on the extent of heating/destabilization, strong storms will be possible during the afternoon/evening across this region, though potential for a corridor of more organized severe threat is quite uncertain at this time. Isolated strong storms will also be possible in the CO Front Range vicinity, where somewhat more favorable deep-layer shear may be in place, but it remains uncertain if destabilization will be sufficient to support a severe-hail threat. ..Dean.. 09/18/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0220 PM CDT Thu Sep 18 2025 Valid 201200Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not currently expected on Saturday. ...Synopsis... A broad mid/upper-level trough will remain across parts of the central CONUS on Saturday, as multiple embedded shortwaves traverse parts of the northern Plains and Upper Midwest. Farther west, a mid/upper-level trough offshore of southern CA is forecast to move slowly eastward, while a stronger mid/upper-level shortwave trough will approach the Pacific Northwest later in the period. The broadly cyclonic flow regime will support thunderstorm potential across a large part of the CONUS, though generally weak deep-layer shear should tend to limit the organized severe threat. Scattered storms will again be possible across the Upper Midwest/Great Lakes, where relatively cool temperatures aloft could support a few strong storms. Morning convection is expected across parts of KS, with redevelopment possible during the afternoon from parts of OK/KS into the mid MS Valley. Depending on the extent of heating/destabilization, strong storms will be possible during the afternoon/evening across this region, though potential for a corridor of more organized severe threat is quite uncertain at this time. Isolated strong storms will also be possible in the CO Front Range vicinity, where somewhat more favorable deep-layer shear may be in place, but it remains uncertain if destabilization will be sufficient to support a severe-hail threat. ..Dean.. 09/18/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 PM CDT Thu Sep 18 2025 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR SOUTHWEST NE INTO WESTERN/CENTRAL KS... ...SUMMARY... Isolated severe storms are possible across parts of the central Plains on Friday. Isolated strong storms may also occur across parts of the Southwest and from the ArkLaTex into the Upper Midwest. ...Synopsis... A broad mid/upper-level trough will remain in place across parts of the northern/central Plains and Upper Midwest on Friday. Multiple embedded vorticity maxima will move traverse the larger-scale trough through the period. Across the West, a midlevel shortwave trough will move across parts of central/northern CA/NV, while a deeper mid/upper-level trough offshore of southern CA will move slowly eastward. ...KS/southern NE vicinity... A somewhat conditional Marginal Risk has been added from southwest NE into western KS, due to the potential for isolated supercells within a northwest-flow regime. Guidance has generally trended toward a more vigorous midlevel shortwave trough and jet maximum moving southeastward from the northern High Plains toward the lower MO Valley through the period. In response to this system, a weak surface low is forecast to develop across the central High Plains. Guidance continues to vary somewhat regarding the placement of any surface boundaries and extent of low-level moisture return during the day, but at least isolated storm development will be possible by late afternoon from southern NE into northwest KS. Deep-layer shear will become favorable for organized convection within the northwesterly flow regime along the southwest periphery of the aforementioned shortwave trough. Buoyancy may remain relatively modest (with MLCAPE of 500-1500 J/kg), but recent CAM guidance depicts potential for isolated supercell development, which could pose a threat for localized hail and gusty winds. A more uncertain scenario is for convection directly associated with the shortwave trough to intensify as it approaches southeast NE, but there is considerable uncertainty regarding diurnal destabilization in this area. A strengthening low-level jet could support some storm clustering and maintenance of elevated convection into late Friday night across parts of KS. Longevity of the severe threat into Friday night is uncertain, but isolated hail and strong gusts cannot be ruled out within this nocturnal regime as well. ...Upper Midwest... A midlevel shortwave trough initially over parts of IA/MO is generally forecast to move north-northeastward toward MN/WI through the day, as the trailing shortwave moves into the central Plains/lower MO Valley. Scattered to numerous storms will be possible across parts of the Upper Midwest/MS Valley, within a relatively moist and uncapped environment. Midlevel lapse rates and deep-layer shear are generally forecast to remain rather weak, so any severe threat will likely be dependent on sufficient diurnal heating/destabilization. Confidence in a mesoscale corridor of organized severe threat is too low for probabilities at this time, but a few strong storms will be possible. ...ArkLaTex into the lower/mid MS Valley... Scattered storm development will be possible during the afternoon from the ArkLaTex into the lower/mid MS Valley, though details regarding heating/destabilization are somewhat uncertain, due to the potential impact of upstream morning convection and related cloud debris. While deep-layer flow/shear will generally be weak across the region, a few strong storms will be possible if sufficient heating occurs. Severe probabilities may eventually be needed if confidence increases regarding stronger diurnal destabilization. ...Southwest... Scattered to widespread storms will again be possible across parts of the Southwest on Friday, within a relatively moist and moderately unstable environment. Deep-layer shear will generally be modest, resulting in uncertainty regarding any organized severe potential. However, localized strong gusts and small to near-severe hail will be possible with the strongest storms. ..Dean.. 09/18/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 PM CDT Thu Sep 18 2025 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR SOUTHWEST NE INTO WESTERN/CENTRAL KS... ...SUMMARY... Isolated severe storms are possible across parts of the central Plains on Friday. Isolated strong storms may also occur across parts of the Southwest and from the ArkLaTex into the Upper Midwest. ...Synopsis... A broad mid/upper-level trough will remain in place across parts of the northern/central Plains and Upper Midwest on Friday. Multiple embedded vorticity maxima will move traverse the larger-scale trough through the period. Across the West, a midlevel shortwave trough will move across parts of central/northern CA/NV, while a deeper mid/upper-level trough offshore of southern CA will move slowly eastward. ...KS/southern NE vicinity... A somewhat conditional Marginal Risk has been added from southwest NE into western KS, due to the potential for isolated supercells within a northwest-flow regime. Guidance has generally trended toward a more vigorous midlevel shortwave trough and jet maximum moving southeastward from the northern High Plains toward the lower MO Valley through the period. In response to this system, a weak surface low is forecast to develop across the central High Plains. Guidance continues to vary somewhat regarding the placement of any surface boundaries and extent of low-level moisture return during the day, but at least isolated storm development will be possible by late afternoon from southern NE into northwest KS. Deep-layer shear will become favorable for organized convection within the northwesterly flow regime along the southwest periphery of the aforementioned shortwave trough. Buoyancy may remain relatively modest (with MLCAPE of 500-1500 J/kg), but recent CAM guidance depicts potential for isolated supercell development, which could pose a threat for localized hail and gusty winds. A more uncertain scenario is for convection directly associated with the shortwave trough to intensify as it approaches southeast NE, but there is considerable uncertainty regarding diurnal destabilization in this area. A strengthening low-level jet could support some storm clustering and maintenance of elevated convection into late Friday night across parts of KS. Longevity of the severe threat into Friday night is uncertain, but isolated hail and strong gusts cannot be ruled out within this nocturnal regime as well. ...Upper Midwest... A midlevel shortwave trough initially over parts of IA/MO is generally forecast to move north-northeastward toward MN/WI through the day, as the trailing shortwave moves into the central Plains/lower MO Valley. Scattered to numerous storms will be possible across parts of the Upper Midwest/MS Valley, within a relatively moist and uncapped environment. Midlevel lapse rates and deep-layer shear are generally forecast to remain rather weak, so any severe threat will likely be dependent on sufficient diurnal heating/destabilization. Confidence in a mesoscale corridor of organized severe threat is too low for probabilities at this time, but a few strong storms will be possible. ...ArkLaTex into the lower/mid MS Valley... Scattered storm development will be possible during the afternoon from the ArkLaTex into the lower/mid MS Valley, though details regarding heating/destabilization are somewhat uncertain, due to the potential impact of upstream morning convection and related cloud debris. While deep-layer flow/shear will generally be weak across the region, a few strong storms will be possible if sufficient heating occurs. Severe probabilities may eventually be needed if confidence increases regarding stronger diurnal destabilization. ...Southwest... Scattered to widespread storms will again be possible across parts of the Southwest on Friday, within a relatively moist and moderately unstable environment. Deep-layer shear will generally be modest, resulting in uncertainty regarding any organized severe potential. However, localized strong gusts and small to near-severe hail will be possible with the strongest storms. ..Dean.. 09/18/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 PM CDT Thu Sep 18 2025 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR SOUTHWEST NE INTO WESTERN/CENTRAL KS... ...SUMMARY... Isolated severe storms are possible across parts of the central Plains on Friday. Isolated strong storms may also occur across parts of the Southwest and from the ArkLaTex into the Upper Midwest. ...Synopsis... A broad mid/upper-level trough will remain in place across parts of the northern/central Plains and Upper Midwest on Friday. Multiple embedded vorticity maxima will move traverse the larger-scale trough through the period. Across the West, a midlevel shortwave trough will move across parts of central/northern CA/NV, while a deeper mid/upper-level trough offshore of southern CA will move slowly eastward. ...KS/southern NE vicinity... A somewhat conditional Marginal Risk has been added from southwest NE into western KS, due to the potential for isolated supercells within a northwest-flow regime. Guidance has generally trended toward a more vigorous midlevel shortwave trough and jet maximum moving southeastward from the northern High Plains toward the lower MO Valley through the period. In response to this system, a weak surface low is forecast to develop across the central High Plains. Guidance continues to vary somewhat regarding the placement of any surface boundaries and extent of low-level moisture return during the day, but at least isolated storm development will be possible by late afternoon from southern NE into northwest KS. Deep-layer shear will become favorable for organized convection within the northwesterly flow regime along the southwest periphery of the aforementioned shortwave trough. Buoyancy may remain relatively modest (with MLCAPE of 500-1500 J/kg), but recent CAM guidance depicts potential for isolated supercell development, which could pose a threat for localized hail and gusty winds. A more uncertain scenario is for convection directly associated with the shortwave trough to intensify as it approaches southeast NE, but there is considerable uncertainty regarding diurnal destabilization in this area. A strengthening low-level jet could support some storm clustering and maintenance of elevated convection into late Friday night across parts of KS. Longevity of the severe threat into Friday night is uncertain, but isolated hail and strong gusts cannot be ruled out within this nocturnal regime as well. ...Upper Midwest... A midlevel shortwave trough initially over parts of IA/MO is generally forecast to move north-northeastward toward MN/WI through the day, as the trailing shortwave moves into the central Plains/lower MO Valley. Scattered to numerous storms will be possible across parts of the Upper Midwest/MS Valley, within a relatively moist and uncapped environment. Midlevel lapse rates and deep-layer shear are generally forecast to remain rather weak, so any severe threat will likely be dependent on sufficient diurnal heating/destabilization. Confidence in a mesoscale corridor of organized severe threat is too low for probabilities at this time, but a few strong storms will be possible. ...ArkLaTex into the lower/mid MS Valley... Scattered storm development will be possible during the afternoon from the ArkLaTex into the lower/mid MS Valley, though details regarding heating/destabilization are somewhat uncertain, due to the potential impact of upstream morning convection and related cloud debris. While deep-layer flow/shear will generally be weak across the region, a few strong storms will be possible if sufficient heating occurs. Severe probabilities may eventually be needed if confidence increases regarding stronger diurnal destabilization. ...Southwest... Scattered to widespread storms will again be possible across parts of the Southwest on Friday, within a relatively moist and moderately unstable environment. Deep-layer shear will generally be modest, resulting in uncertainty regarding any organized severe potential. However, localized strong gusts and small to near-severe hail will be possible with the strongest storms. ..Dean.. 09/18/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 PM CDT Thu Sep 18 2025 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR SOUTHWEST NE INTO WESTERN/CENTRAL KS... ...SUMMARY... Isolated severe storms are possible across parts of the central Plains on Friday. Isolated strong storms may also occur across parts of the Southwest and from the ArkLaTex into the Upper Midwest. ...Synopsis... A broad mid/upper-level trough will remain in place across parts of the northern/central Plains and Upper Midwest on Friday. Multiple embedded vorticity maxima will move traverse the larger-scale trough through the period. Across the West, a midlevel shortwave trough will move across parts of central/northern CA/NV, while a deeper mid/upper-level trough offshore of southern CA will move slowly eastward. ...KS/southern NE vicinity... A somewhat conditional Marginal Risk has been added from southwest NE into western KS, due to the potential for isolated supercells within a northwest-flow regime. Guidance has generally trended toward a more vigorous midlevel shortwave trough and jet maximum moving southeastward from the northern High Plains toward the lower MO Valley through the period. In response to this system, a weak surface low is forecast to develop across the central High Plains. Guidance continues to vary somewhat regarding the placement of any surface boundaries and extent of low-level moisture return during the day, but at least isolated storm development will be possible by late afternoon from southern NE into northwest KS. Deep-layer shear will become favorable for organized convection within the northwesterly flow regime along the southwest periphery of the aforementioned shortwave trough. Buoyancy may remain relatively modest (with MLCAPE of 500-1500 J/kg), but recent CAM guidance depicts potential for isolated supercell development, which could pose a threat for localized hail and gusty winds. A more uncertain scenario is for convection directly associated with the shortwave trough to intensify as it approaches southeast NE, but there is considerable uncertainty regarding diurnal destabilization in this area. A strengthening low-level jet could support some storm clustering and maintenance of elevated convection into late Friday night across parts of KS. Longevity of the severe threat into Friday night is uncertain, but isolated hail and strong gusts cannot be ruled out within this nocturnal regime as well. ...Upper Midwest... A midlevel shortwave trough initially over parts of IA/MO is generally forecast to move north-northeastward toward MN/WI through the day, as the trailing shortwave moves into the central Plains/lower MO Valley. Scattered to numerous storms will be possible across parts of the Upper Midwest/MS Valley, within a relatively moist and uncapped environment. Midlevel lapse rates and deep-layer shear are generally forecast to remain rather weak, so any severe threat will likely be dependent on sufficient diurnal heating/destabilization. Confidence in a mesoscale corridor of organized severe threat is too low for probabilities at this time, but a few strong storms will be possible. ...ArkLaTex into the lower/mid MS Valley... Scattered storm development will be possible during the afternoon from the ArkLaTex into the lower/mid MS Valley, though details regarding heating/destabilization are somewhat uncertain, due to the potential impact of upstream morning convection and related cloud debris. While deep-layer flow/shear will generally be weak across the region, a few strong storms will be possible if sufficient heating occurs. Severe probabilities may eventually be needed if confidence increases regarding stronger diurnal destabilization. ...Southwest... Scattered to widespread storms will again be possible across parts of the Southwest on Friday, within a relatively moist and moderately unstable environment. Deep-layer shear will generally be modest, resulting in uncertainty regarding any organized severe potential. However, localized strong gusts and small to near-severe hail will be possible with the strongest storms. ..Dean.. 09/18/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 PM CDT Thu Sep 18 2025 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR SOUTHWEST NE INTO WESTERN/CENTRAL KS... ...SUMMARY... Isolated severe storms are possible across parts of the central Plains on Friday. Isolated strong storms may also occur across parts of the Southwest and from the ArkLaTex into the Upper Midwest. ...Synopsis... A broad mid/upper-level trough will remain in place across parts of the northern/central Plains and Upper Midwest on Friday. Multiple embedded vorticity maxima will move traverse the larger-scale trough through the period. Across the West, a midlevel shortwave trough will move across parts of central/northern CA/NV, while a deeper mid/upper-level trough offshore of southern CA will move slowly eastward. ...KS/southern NE vicinity... A somewhat conditional Marginal Risk has been added from southwest NE into western KS, due to the potential for isolated supercells within a northwest-flow regime. Guidance has generally trended toward a more vigorous midlevel shortwave trough and jet maximum moving southeastward from the northern High Plains toward the lower MO Valley through the period. In response to this system, a weak surface low is forecast to develop across the central High Plains. Guidance continues to vary somewhat regarding the placement of any surface boundaries and extent of low-level moisture return during the day, but at least isolated storm development will be possible by late afternoon from southern NE into northwest KS. Deep-layer shear will become favorable for organized convection within the northwesterly flow regime along the southwest periphery of the aforementioned shortwave trough. Buoyancy may remain relatively modest (with MLCAPE of 500-1500 J/kg), but recent CAM guidance depicts potential for isolated supercell development, which could pose a threat for localized hail and gusty winds. A more uncertain scenario is for convection directly associated with the shortwave trough to intensify as it approaches southeast NE, but there is considerable uncertainty regarding diurnal destabilization in this area. A strengthening low-level jet could support some storm clustering and maintenance of elevated convection into late Friday night across parts of KS. Longevity of the severe threat into Friday night is uncertain, but isolated hail and strong gusts cannot be ruled out within this nocturnal regime as well. ...Upper Midwest... A midlevel shortwave trough initially over parts of IA/MO is generally forecast to move north-northeastward toward MN/WI through the day, as the trailing shortwave moves into the central Plains/lower MO Valley. Scattered to numerous storms will be possible across parts of the Upper Midwest/MS Valley, within a relatively moist and uncapped environment. Midlevel lapse rates and deep-layer shear are generally forecast to remain rather weak, so any severe threat will likely be dependent on sufficient diurnal heating/destabilization. Confidence in a mesoscale corridor of organized severe threat is too low for probabilities at this time, but a few strong storms will be possible. ...ArkLaTex into the lower/mid MS Valley... Scattered storm development will be possible during the afternoon from the ArkLaTex into the lower/mid MS Valley, though details regarding heating/destabilization are somewhat uncertain, due to the potential impact of upstream morning convection and related cloud debris. While deep-layer flow/shear will generally be weak across the region, a few strong storms will be possible if sufficient heating occurs. Severe probabilities may eventually be needed if confidence increases regarding stronger diurnal destabilization. ...Southwest... Scattered to widespread storms will again be possible across parts of the Southwest on Friday, within a relatively moist and moderately unstable environment. Deep-layer shear will generally be modest, resulting in uncertainty regarding any organized severe potential. However, localized strong gusts and small to near-severe hail will be possible with the strongest storms. ..Dean.. 09/18/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 PM CDT Thu Sep 18 2025 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR SOUTHWEST NE INTO WESTERN/CENTRAL KS... ...SUMMARY... Isolated severe storms are possible across parts of the central Plains on Friday. Isolated strong storms may also occur across parts of the Southwest and from the ArkLaTex into the Upper Midwest. ...Synopsis... A broad mid/upper-level trough will remain in place across parts of the northern/central Plains and Upper Midwest on Friday. Multiple embedded vorticity maxima will move traverse the larger-scale trough through the period. Across the West, a midlevel shortwave trough will move across parts of central/northern CA/NV, while a deeper mid/upper-level trough offshore of southern CA will move slowly eastward. ...KS/southern NE vicinity... A somewhat conditional Marginal Risk has been added from southwest NE into western KS, due to the potential for isolated supercells within a northwest-flow regime. Guidance has generally trended toward a more vigorous midlevel shortwave trough and jet maximum moving southeastward from the northern High Plains toward the lower MO Valley through the period. In response to this system, a weak surface low is forecast to develop across the central High Plains. Guidance continues to vary somewhat regarding the placement of any surface boundaries and extent of low-level moisture return during the day, but at least isolated storm development will be possible by late afternoon from southern NE into northwest KS. Deep-layer shear will become favorable for organized convection within the northwesterly flow regime along the southwest periphery of the aforementioned shortwave trough. Buoyancy may remain relatively modest (with MLCAPE of 500-1500 J/kg), but recent CAM guidance depicts potential for isolated supercell development, which could pose a threat for localized hail and gusty winds. A more uncertain scenario is for convection directly associated with the shortwave trough to intensify as it approaches southeast NE, but there is considerable uncertainty regarding diurnal destabilization in this area. A strengthening low-level jet could support some storm clustering and maintenance of elevated convection into late Friday night across parts of KS. Longevity of the severe threat into Friday night is uncertain, but isolated hail and strong gusts cannot be ruled out within this nocturnal regime as well. ...Upper Midwest... A midlevel shortwave trough initially over parts of IA/MO is generally forecast to move north-northeastward toward MN/WI through the day, as the trailing shortwave moves into the central Plains/lower MO Valley. Scattered to numerous storms will be possible across parts of the Upper Midwest/MS Valley, within a relatively moist and uncapped environment. Midlevel lapse rates and deep-layer shear are generally forecast to remain rather weak, so any severe threat will likely be dependent on sufficient diurnal heating/destabilization. Confidence in a mesoscale corridor of organized severe threat is too low for probabilities at this time, but a few strong storms will be possible. ...ArkLaTex into the lower/mid MS Valley... Scattered storm development will be possible during the afternoon from the ArkLaTex into the lower/mid MS Valley, though details regarding heating/destabilization are somewhat uncertain, due to the potential impact of upstream morning convection and related cloud debris. While deep-layer flow/shear will generally be weak across the region, a few strong storms will be possible if sufficient heating occurs. Severe probabilities may eventually be needed if confidence increases regarding stronger diurnal destabilization. ...Southwest... Scattered to widespread storms will again be possible across parts of the Southwest on Friday, within a relatively moist and moderately unstable environment. Deep-layer shear will generally be modest, resulting in uncertainty regarding any organized severe potential. However, localized strong gusts and small to near-severe hail will be possible with the strongest storms. ..Dean.. 09/18/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 PM CDT Thu Sep 18 2025 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR SOUTHWEST NE INTO WESTERN/CENTRAL KS... ...SUMMARY... Isolated severe storms are possible across parts of the central Plains on Friday. Isolated strong storms may also occur across parts of the Southwest and from the ArkLaTex into the Upper Midwest. ...Synopsis... A broad mid/upper-level trough will remain in place across parts of the northern/central Plains and Upper Midwest on Friday. Multiple embedded vorticity maxima will move traverse the larger-scale trough through the period. Across the West, a midlevel shortwave trough will move across parts of central/northern CA/NV, while a deeper mid/upper-level trough offshore of southern CA will move slowly eastward. ...KS/southern NE vicinity... A somewhat conditional Marginal Risk has been added from southwest NE into western KS, due to the potential for isolated supercells within a northwest-flow regime. Guidance has generally trended toward a more vigorous midlevel shortwave trough and jet maximum moving southeastward from the northern High Plains toward the lower MO Valley through the period. In response to this system, a weak surface low is forecast to develop across the central High Plains. Guidance continues to vary somewhat regarding the placement of any surface boundaries and extent of low-level moisture return during the day, but at least isolated storm development will be possible by late afternoon from southern NE into northwest KS. Deep-layer shear will become favorable for organized convection within the northwesterly flow regime along the southwest periphery of the aforementioned shortwave trough. Buoyancy may remain relatively modest (with MLCAPE of 500-1500 J/kg), but recent CAM guidance depicts potential for isolated supercell development, which could pose a threat for localized hail and gusty winds. A more uncertain scenario is for convection directly associated with the shortwave trough to intensify as it approaches southeast NE, but there is considerable uncertainty regarding diurnal destabilization in this area. A strengthening low-level jet could support some storm clustering and maintenance of elevated convection into late Friday night across parts of KS. Longevity of the severe threat into Friday night is uncertain, but isolated hail and strong gusts cannot be ruled out within this nocturnal regime as well. ...Upper Midwest... A midlevel shortwave trough initially over parts of IA/MO is generally forecast to move north-northeastward toward MN/WI through the day, as the trailing shortwave moves into the central Plains/lower MO Valley. Scattered to numerous storms will be possible across parts of the Upper Midwest/MS Valley, within a relatively moist and uncapped environment. Midlevel lapse rates and deep-layer shear are generally forecast to remain rather weak, so any severe threat will likely be dependent on sufficient diurnal heating/destabilization. Confidence in a mesoscale corridor of organized severe threat is too low for probabilities at this time, but a few strong storms will be possible. ...ArkLaTex into the lower/mid MS Valley... Scattered storm development will be possible during the afternoon from the ArkLaTex into the lower/mid MS Valley, though details regarding heating/destabilization are somewhat uncertain, due to the potential impact of upstream morning convection and related cloud debris. While deep-layer flow/shear will generally be weak across the region, a few strong storms will be possible if sufficient heating occurs. Severe probabilities may eventually be needed if confidence increases regarding stronger diurnal destabilization. ...Southwest... Scattered to widespread storms will again be possible across parts of the Southwest on Friday, within a relatively moist and moderately unstable environment. Deep-layer shear will generally be modest, resulting in uncertainty regarding any organized severe potential. However, localized strong gusts and small to near-severe hail will be possible with the strongest storms. ..Dean.. 09/18/2025 Read more