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SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CST Thu Feb 08 2024 Valid 091200Z - 101200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe potential currently appears rather uncertain Friday into Friday night, but trends will be closely monitored from parts of eastern Oklahoma through the mid Mississippi Valley and lower Ohio Valley. ...Synopsis and Discussion... With positive-tilt mid/upper-level troughing persisting over much of the central/eastern CONUS on Friday, the primary feature of interest for convective potential will be a compact shortwave trough ejecting across the southern/central Plains through the day, and over the mid MS and OH Valleys late Friday into early Saturday morning. An occluded surface low is forecast to advance northeastward across Ontario through the period, while a separate, weak surface low attendant to the ejecting mid-level shortwave trough develops from the central High Plains to the Midwest. Weak thunderstorms may be ongoing Friday morning along/near a remnant surface boundary across parts of the Mid-South and TN Valley in a modest low-level warm advection regime. Additional convective development ahead of the shortwave trough and associated surface low/cold front will likely be delayed until Friday evening at the earliest, with residual capping and MLCIN generally inhibiting thunderstorm initiation. Still, at least isolated thunderstorms may eventually form over parts of eastern OK and the Ozarks, and spread east-northeastward across parts of the mid MS Valley and lower OH Valley Friday night. Some low-level moisture return is anticipated across these regions ahead of the east-southeastward moving cold front, but there is still a fair amount of uncertainty with how much boundary-layer instability will be realized, and whether thunderstorms will remain elevated or become surface based. The 12Z NAM is notably more aggressive than most other guidance in depicting greater low-level moisture and related instability across MO/AR eastward into the lower OH Valley late Friday into early Saturday morning. Given strong deep-layer shear and adequate low-level shear forecast, any surface-based thunderstorms that can develop and persist would conditionally support a severe risk. But, this potential still appears highly uncertain and conditional, with a better chance that convection remains slightly elevated above a near-surface stable layer. Have therefore opted to not include any low severe probabilities at this time, while expanding the general thunderstorm area northward to account for a larger zone of possible thunderstorm development. ..Gleason.. 02/08/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CST Thu Feb 08 2024 Valid 091200Z - 101200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe potential currently appears rather uncertain Friday into Friday night, but trends will be closely monitored from parts of eastern Oklahoma through the mid Mississippi Valley and lower Ohio Valley. ...Synopsis and Discussion... With positive-tilt mid/upper-level troughing persisting over much of the central/eastern CONUS on Friday, the primary feature of interest for convective potential will be a compact shortwave trough ejecting across the southern/central Plains through the day, and over the mid MS and OH Valleys late Friday into early Saturday morning. An occluded surface low is forecast to advance northeastward across Ontario through the period, while a separate, weak surface low attendant to the ejecting mid-level shortwave trough develops from the central High Plains to the Midwest. Weak thunderstorms may be ongoing Friday morning along/near a remnant surface boundary across parts of the Mid-South and TN Valley in a modest low-level warm advection regime. Additional convective development ahead of the shortwave trough and associated surface low/cold front will likely be delayed until Friday evening at the earliest, with residual capping and MLCIN generally inhibiting thunderstorm initiation. Still, at least isolated thunderstorms may eventually form over parts of eastern OK and the Ozarks, and spread east-northeastward across parts of the mid MS Valley and lower OH Valley Friday night. Some low-level moisture return is anticipated across these regions ahead of the east-southeastward moving cold front, but there is still a fair amount of uncertainty with how much boundary-layer instability will be realized, and whether thunderstorms will remain elevated or become surface based. The 12Z NAM is notably more aggressive than most other guidance in depicting greater low-level moisture and related instability across MO/AR eastward into the lower OH Valley late Friday into early Saturday morning. Given strong deep-layer shear and adequate low-level shear forecast, any surface-based thunderstorms that can develop and persist would conditionally support a severe risk. But, this potential still appears highly uncertain and conditional, with a better chance that convection remains slightly elevated above a near-surface stable layer. Have therefore opted to not include any low severe probabilities at this time, while expanding the general thunderstorm area northward to account for a larger zone of possible thunderstorm development. ..Gleason.. 02/08/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CST Thu Feb 08 2024 Valid 091200Z - 101200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe potential currently appears rather uncertain Friday into Friday night, but trends will be closely monitored from parts of eastern Oklahoma through the mid Mississippi Valley and lower Ohio Valley. ...Synopsis and Discussion... With positive-tilt mid/upper-level troughing persisting over much of the central/eastern CONUS on Friday, the primary feature of interest for convective potential will be a compact shortwave trough ejecting across the southern/central Plains through the day, and over the mid MS and OH Valleys late Friday into early Saturday morning. An occluded surface low is forecast to advance northeastward across Ontario through the period, while a separate, weak surface low attendant to the ejecting mid-level shortwave trough develops from the central High Plains to the Midwest. Weak thunderstorms may be ongoing Friday morning along/near a remnant surface boundary across parts of the Mid-South and TN Valley in a modest low-level warm advection regime. Additional convective development ahead of the shortwave trough and associated surface low/cold front will likely be delayed until Friday evening at the earliest, with residual capping and MLCIN generally inhibiting thunderstorm initiation. Still, at least isolated thunderstorms may eventually form over parts of eastern OK and the Ozarks, and spread east-northeastward across parts of the mid MS Valley and lower OH Valley Friday night. Some low-level moisture return is anticipated across these regions ahead of the east-southeastward moving cold front, but there is still a fair amount of uncertainty with how much boundary-layer instability will be realized, and whether thunderstorms will remain elevated or become surface based. The 12Z NAM is notably more aggressive than most other guidance in depicting greater low-level moisture and related instability across MO/AR eastward into the lower OH Valley late Friday into early Saturday morning. Given strong deep-layer shear and adequate low-level shear forecast, any surface-based thunderstorms that can develop and persist would conditionally support a severe risk. But, this potential still appears highly uncertain and conditional, with a better chance that convection remains slightly elevated above a near-surface stable layer. Have therefore opted to not include any low severe probabilities at this time, while expanding the general thunderstorm area northward to account for a larger zone of possible thunderstorm development. ..Gleason.. 02/08/2024 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1039 AM CST Thu Feb 08 2024 Valid 081700Z - 091200Z ...NO CRITICAL AREAS... ...17z Update... Morning observations show wind gusts of 25-30+ mph and pockets of lower humidity becoming more numerous across the southern Plains. Winds should continue to increase through the day as a weak dryline mixes eastward. Locally elevated to near-critical meteorological conditions are possible this afternoon over parts of eastern OK/KS and western MO. However, area fuels remain poorly receptive to fire starts/spread, suggesting fire-weather concerns will remain localized. See the previous discussion for more information. ..Lyons.. 02/08/2024 .PREV DISCUSSION... /ISSUED 1258 AM CST Thu Feb 08 2024/ ...Synopsis... A mid-level impulse embedded in a broad upper-level cyclonic flow regime will impinge on the Plains states today, encouraging surface low development along the central High Plains. While low-level moisture will continue to return northward across portions of the Plains states, downslope westerly flow along the southern High Plains will support dry and windy surface conditions during the afternoon. While these conditions may reach elevated-equivalent thresholds in spots, fuels appear poorly receptive to fire spread, precluding the introduction of fire weather highlights. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1039 AM CST Thu Feb 08 2024 Valid 081700Z - 091200Z ...NO CRITICAL AREAS... ...17z Update... Morning observations show wind gusts of 25-30+ mph and pockets of lower humidity becoming more numerous across the southern Plains. Winds should continue to increase through the day as a weak dryline mixes eastward. Locally elevated to near-critical meteorological conditions are possible this afternoon over parts of eastern OK/KS and western MO. However, area fuels remain poorly receptive to fire starts/spread, suggesting fire-weather concerns will remain localized. See the previous discussion for more information. ..Lyons.. 02/08/2024 .PREV DISCUSSION... /ISSUED 1258 AM CST Thu Feb 08 2024/ ...Synopsis... A mid-level impulse embedded in a broad upper-level cyclonic flow regime will impinge on the Plains states today, encouraging surface low development along the central High Plains. While low-level moisture will continue to return northward across portions of the Plains states, downslope westerly flow along the southern High Plains will support dry and windy surface conditions during the afternoon. While these conditions may reach elevated-equivalent thresholds in spots, fuels appear poorly receptive to fire spread, precluding the introduction of fire weather highlights. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1039 AM CST Thu Feb 08 2024 Valid 081700Z - 091200Z ...NO CRITICAL AREAS... ...17z Update... Morning observations show wind gusts of 25-30+ mph and pockets of lower humidity becoming more numerous across the southern Plains. Winds should continue to increase through the day as a weak dryline mixes eastward. Locally elevated to near-critical meteorological conditions are possible this afternoon over parts of eastern OK/KS and western MO. However, area fuels remain poorly receptive to fire starts/spread, suggesting fire-weather concerns will remain localized. See the previous discussion for more information. ..Lyons.. 02/08/2024 .PREV DISCUSSION... /ISSUED 1258 AM CST Thu Feb 08 2024/ ...Synopsis... A mid-level impulse embedded in a broad upper-level cyclonic flow regime will impinge on the Plains states today, encouraging surface low development along the central High Plains. While low-level moisture will continue to return northward across portions of the Plains states, downslope westerly flow along the southern High Plains will support dry and windy surface conditions during the afternoon. While these conditions may reach elevated-equivalent thresholds in spots, fuels appear poorly receptive to fire spread, precluding the introduction of fire weather highlights. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1039 AM CST Thu Feb 08 2024 Valid 081700Z - 091200Z ...NO CRITICAL AREAS... ...17z Update... Morning observations show wind gusts of 25-30+ mph and pockets of lower humidity becoming more numerous across the southern Plains. Winds should continue to increase through the day as a weak dryline mixes eastward. Locally elevated to near-critical meteorological conditions are possible this afternoon over parts of eastern OK/KS and western MO. However, area fuels remain poorly receptive to fire starts/spread, suggesting fire-weather concerns will remain localized. See the previous discussion for more information. ..Lyons.. 02/08/2024 .PREV DISCUSSION... /ISSUED 1258 AM CST Thu Feb 08 2024/ ...Synopsis... A mid-level impulse embedded in a broad upper-level cyclonic flow regime will impinge on the Plains states today, encouraging surface low development along the central High Plains. While low-level moisture will continue to return northward across portions of the Plains states, downslope westerly flow along the southern High Plains will support dry and windy surface conditions during the afternoon. While these conditions may reach elevated-equivalent thresholds in spots, fuels appear poorly receptive to fire spread, precluding the introduction of fire weather highlights. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1039 AM CST Thu Feb 08 2024 Valid 081700Z - 091200Z ...NO CRITICAL AREAS... ...17z Update... Morning observations show wind gusts of 25-30+ mph and pockets of lower humidity becoming more numerous across the southern Plains. Winds should continue to increase through the day as a weak dryline mixes eastward. Locally elevated to near-critical meteorological conditions are possible this afternoon over parts of eastern OK/KS and western MO. However, area fuels remain poorly receptive to fire starts/spread, suggesting fire-weather concerns will remain localized. See the previous discussion for more information. ..Lyons.. 02/08/2024 .PREV DISCUSSION... /ISSUED 1258 AM CST Thu Feb 08 2024/ ...Synopsis... A mid-level impulse embedded in a broad upper-level cyclonic flow regime will impinge on the Plains states today, encouraging surface low development along the central High Plains. While low-level moisture will continue to return northward across portions of the Plains states, downslope westerly flow along the southern High Plains will support dry and windy surface conditions during the afternoon. While these conditions may reach elevated-equivalent thresholds in spots, fuels appear poorly receptive to fire spread, precluding the introduction of fire weather highlights. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1039 AM CST Thu Feb 08 2024 Valid 081700Z - 091200Z ...NO CRITICAL AREAS... ...17z Update... Morning observations show wind gusts of 25-30+ mph and pockets of lower humidity becoming more numerous across the southern Plains. Winds should continue to increase through the day as a weak dryline mixes eastward. Locally elevated to near-critical meteorological conditions are possible this afternoon over parts of eastern OK/KS and western MO. However, area fuels remain poorly receptive to fire starts/spread, suggesting fire-weather concerns will remain localized. See the previous discussion for more information. ..Lyons.. 02/08/2024 .PREV DISCUSSION... /ISSUED 1258 AM CST Thu Feb 08 2024/ ...Synopsis... A mid-level impulse embedded in a broad upper-level cyclonic flow regime will impinge on the Plains states today, encouraging surface low development along the central High Plains. While low-level moisture will continue to return northward across portions of the Plains states, downslope westerly flow along the southern High Plains will support dry and windy surface conditions during the afternoon. While these conditions may reach elevated-equivalent thresholds in spots, fuels appear poorly receptive to fire spread, precluding the introduction of fire weather highlights. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1039 AM CST Thu Feb 08 2024 Valid 081700Z - 091200Z ...NO CRITICAL AREAS... ...17z Update... Morning observations show wind gusts of 25-30+ mph and pockets of lower humidity becoming more numerous across the southern Plains. Winds should continue to increase through the day as a weak dryline mixes eastward. Locally elevated to near-critical meteorological conditions are possible this afternoon over parts of eastern OK/KS and western MO. However, area fuels remain poorly receptive to fire starts/spread, suggesting fire-weather concerns will remain localized. See the previous discussion for more information. ..Lyons.. 02/08/2024 .PREV DISCUSSION... /ISSUED 1258 AM CST Thu Feb 08 2024/ ...Synopsis... A mid-level impulse embedded in a broad upper-level cyclonic flow regime will impinge on the Plains states today, encouraging surface low development along the central High Plains. While low-level moisture will continue to return northward across portions of the Plains states, downslope westerly flow along the southern High Plains will support dry and windy surface conditions during the afternoon. While these conditions may reach elevated-equivalent thresholds in spots, fuels appear poorly receptive to fire spread, precluding the introduction of fire weather highlights. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1039 AM CST Thu Feb 08 2024 Valid 081700Z - 091200Z ...NO CRITICAL AREAS... ...17z Update... Morning observations show wind gusts of 25-30+ mph and pockets of lower humidity becoming more numerous across the southern Plains. Winds should continue to increase through the day as a weak dryline mixes eastward. Locally elevated to near-critical meteorological conditions are possible this afternoon over parts of eastern OK/KS and western MO. However, area fuels remain poorly receptive to fire starts/spread, suggesting fire-weather concerns will remain localized. See the previous discussion for more information. ..Lyons.. 02/08/2024 .PREV DISCUSSION... /ISSUED 1258 AM CST Thu Feb 08 2024/ ...Synopsis... A mid-level impulse embedded in a broad upper-level cyclonic flow regime will impinge on the Plains states today, encouraging surface low development along the central High Plains. While low-level moisture will continue to return northward across portions of the Plains states, downslope westerly flow along the southern High Plains will support dry and windy surface conditions during the afternoon. While these conditions may reach elevated-equivalent thresholds in spots, fuels appear poorly receptive to fire spread, precluding the introduction of fire weather highlights. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1030 AM CST Thu Feb 08 2024 Valid 081630Z - 091200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM FAR EASTERN IOWA EASTWARD TO SOUTHWESTERN PARTS OF LAKE MICHIGAN... ...SUMMARY... A few strong/severe thunderstorms remain possible this afternoon through early evening across parts of far eastern Iowa, northern Illinois, far southern Wisconsin, and the southern Lake Michigan vicinity. ...Synopsis... A mid-level short-wave trough now crossing the Middle Missouri Valley/central Plains will continue progressing northeastward today and tonight, while a second feature now in the vicinity of the Lower Colorado Valley shifts eastward through the period. Meanwhile, upper ridging over the East will be shunted progressively eastward by the aforementioned advance of short-wave troughs farther west. At the surface, a rather deep (990 mb) surface cyclone is currently analyzed near the ND/SD/MN border intersection, with a cold front extending southward across the Middle Missouri Valley into Kansas. This boundary, and the advance of the upper trough, may support isolated late afternoon strong/potentially severe convective development across eastern Iowa/northwestern Illinois. Elsewhere, showers and scattered thunderstorms are expected to evolve across the Four Corners states ahead of the aforementioned upper trough, and overnight thunder may evolve within an area of broad/weak QG ascent over parts of the Lower Mississippi and Tennessee Valleys. Severe weather is not expected in these areas. ...Eastern Iowa/northern Illinois/southern Wisconsin vicinity... Low-level moisture remains a primary uncertainty today, with respect to potential strong/severe storm development. Dewpoints remain in the upper 30s/low 40s across the Iowa/Illinois area, where model forecast soundings -- particularly the RAP -- have consistently indicated upper 40s to low 50s dewpoints by late afternoon. This degree of moistening still appears to be a bit aggressive, with middle to upper 40s largely anticipated. With that said, very cold air aloft/steep lapse rates will continue to overspread this region, and the deep-layer wind field is conditionally quite supportive of severe/supercell storms. At this time, we will maintain MRGL risk and all-hazard, low-probability outlook. A couple of storms may develop by late afternoon, in the eastern Iowa/northwestern Illinois vicinity, and then shift eastward/east-northeastward through early evening, before weakening. However, evolution of moisture through the day will be closely watched, as the more aggressive RAP model solution -- should it appear more likely to occur -- would require consideration for an upgrade to the outlook at 20Z. ..Goss/Thornton.. 02/08/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1030 AM CST Thu Feb 08 2024 Valid 081630Z - 091200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM FAR EASTERN IOWA EASTWARD TO SOUTHWESTERN PARTS OF LAKE MICHIGAN... ...SUMMARY... A few strong/severe thunderstorms remain possible this afternoon through early evening across parts of far eastern Iowa, northern Illinois, far southern Wisconsin, and the southern Lake Michigan vicinity. ...Synopsis... A mid-level short-wave trough now crossing the Middle Missouri Valley/central Plains will continue progressing northeastward today and tonight, while a second feature now in the vicinity of the Lower Colorado Valley shifts eastward through the period. Meanwhile, upper ridging over the East will be shunted progressively eastward by the aforementioned advance of short-wave troughs farther west. At the surface, a rather deep (990 mb) surface cyclone is currently analyzed near the ND/SD/MN border intersection, with a cold front extending southward across the Middle Missouri Valley into Kansas. This boundary, and the advance of the upper trough, may support isolated late afternoon strong/potentially severe convective development across eastern Iowa/northwestern Illinois. Elsewhere, showers and scattered thunderstorms are expected to evolve across the Four Corners states ahead of the aforementioned upper trough, and overnight thunder may evolve within an area of broad/weak QG ascent over parts of the Lower Mississippi and Tennessee Valleys. Severe weather is not expected in these areas. ...Eastern Iowa/northern Illinois/southern Wisconsin vicinity... Low-level moisture remains a primary uncertainty today, with respect to potential strong/severe storm development. Dewpoints remain in the upper 30s/low 40s across the Iowa/Illinois area, where model forecast soundings -- particularly the RAP -- have consistently indicated upper 40s to low 50s dewpoints by late afternoon. This degree of moistening still appears to be a bit aggressive, with middle to upper 40s largely anticipated. With that said, very cold air aloft/steep lapse rates will continue to overspread this region, and the deep-layer wind field is conditionally quite supportive of severe/supercell storms. At this time, we will maintain MRGL risk and all-hazard, low-probability outlook. A couple of storms may develop by late afternoon, in the eastern Iowa/northwestern Illinois vicinity, and then shift eastward/east-northeastward through early evening, before weakening. However, evolution of moisture through the day will be closely watched, as the more aggressive RAP model solution -- should it appear more likely to occur -- would require consideration for an upgrade to the outlook at 20Z. ..Goss/Thornton.. 02/08/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1030 AM CST Thu Feb 08 2024 Valid 081630Z - 091200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM FAR EASTERN IOWA EASTWARD TO SOUTHWESTERN PARTS OF LAKE MICHIGAN... ...SUMMARY... A few strong/severe thunderstorms remain possible this afternoon through early evening across parts of far eastern Iowa, northern Illinois, far southern Wisconsin, and the southern Lake Michigan vicinity. ...Synopsis... A mid-level short-wave trough now crossing the Middle Missouri Valley/central Plains will continue progressing northeastward today and tonight, while a second feature now in the vicinity of the Lower Colorado Valley shifts eastward through the period. Meanwhile, upper ridging over the East will be shunted progressively eastward by the aforementioned advance of short-wave troughs farther west. At the surface, a rather deep (990 mb) surface cyclone is currently analyzed near the ND/SD/MN border intersection, with a cold front extending southward across the Middle Missouri Valley into Kansas. This boundary, and the advance of the upper trough, may support isolated late afternoon strong/potentially severe convective development across eastern Iowa/northwestern Illinois. Elsewhere, showers and scattered thunderstorms are expected to evolve across the Four Corners states ahead of the aforementioned upper trough, and overnight thunder may evolve within an area of broad/weak QG ascent over parts of the Lower Mississippi and Tennessee Valleys. Severe weather is not expected in these areas. ...Eastern Iowa/northern Illinois/southern Wisconsin vicinity... Low-level moisture remains a primary uncertainty today, with respect to potential strong/severe storm development. Dewpoints remain in the upper 30s/low 40s across the Iowa/Illinois area, where model forecast soundings -- particularly the RAP -- have consistently indicated upper 40s to low 50s dewpoints by late afternoon. This degree of moistening still appears to be a bit aggressive, with middle to upper 40s largely anticipated. With that said, very cold air aloft/steep lapse rates will continue to overspread this region, and the deep-layer wind field is conditionally quite supportive of severe/supercell storms. At this time, we will maintain MRGL risk and all-hazard, low-probability outlook. A couple of storms may develop by late afternoon, in the eastern Iowa/northwestern Illinois vicinity, and then shift eastward/east-northeastward through early evening, before weakening. However, evolution of moisture through the day will be closely watched, as the more aggressive RAP model solution -- should it appear more likely to occur -- would require consideration for an upgrade to the outlook at 20Z. ..Goss/Thornton.. 02/08/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1030 AM CST Thu Feb 08 2024 Valid 081630Z - 091200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM FAR EASTERN IOWA EASTWARD TO SOUTHWESTERN PARTS OF LAKE MICHIGAN... ...SUMMARY... A few strong/severe thunderstorms remain possible this afternoon through early evening across parts of far eastern Iowa, northern Illinois, far southern Wisconsin, and the southern Lake Michigan vicinity. ...Synopsis... A mid-level short-wave trough now crossing the Middle Missouri Valley/central Plains will continue progressing northeastward today and tonight, while a second feature now in the vicinity of the Lower Colorado Valley shifts eastward through the period. Meanwhile, upper ridging over the East will be shunted progressively eastward by the aforementioned advance of short-wave troughs farther west. At the surface, a rather deep (990 mb) surface cyclone is currently analyzed near the ND/SD/MN border intersection, with a cold front extending southward across the Middle Missouri Valley into Kansas. This boundary, and the advance of the upper trough, may support isolated late afternoon strong/potentially severe convective development across eastern Iowa/northwestern Illinois. Elsewhere, showers and scattered thunderstorms are expected to evolve across the Four Corners states ahead of the aforementioned upper trough, and overnight thunder may evolve within an area of broad/weak QG ascent over parts of the Lower Mississippi and Tennessee Valleys. Severe weather is not expected in these areas. ...Eastern Iowa/northern Illinois/southern Wisconsin vicinity... Low-level moisture remains a primary uncertainty today, with respect to potential strong/severe storm development. Dewpoints remain in the upper 30s/low 40s across the Iowa/Illinois area, where model forecast soundings -- particularly the RAP -- have consistently indicated upper 40s to low 50s dewpoints by late afternoon. This degree of moistening still appears to be a bit aggressive, with middle to upper 40s largely anticipated. With that said, very cold air aloft/steep lapse rates will continue to overspread this region, and the deep-layer wind field is conditionally quite supportive of severe/supercell storms. At this time, we will maintain MRGL risk and all-hazard, low-probability outlook. A couple of storms may develop by late afternoon, in the eastern Iowa/northwestern Illinois vicinity, and then shift eastward/east-northeastward through early evening, before weakening. However, evolution of moisture through the day will be closely watched, as the more aggressive RAP model solution -- should it appear more likely to occur -- would require consideration for an upgrade to the outlook at 20Z. ..Goss/Thornton.. 02/08/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1030 AM CST Thu Feb 08 2024 Valid 081630Z - 091200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM FAR EASTERN IOWA EASTWARD TO SOUTHWESTERN PARTS OF LAKE MICHIGAN... ...SUMMARY... A few strong/severe thunderstorms remain possible this afternoon through early evening across parts of far eastern Iowa, northern Illinois, far southern Wisconsin, and the southern Lake Michigan vicinity. ...Synopsis... A mid-level short-wave trough now crossing the Middle Missouri Valley/central Plains will continue progressing northeastward today and tonight, while a second feature now in the vicinity of the Lower Colorado Valley shifts eastward through the period. Meanwhile, upper ridging over the East will be shunted progressively eastward by the aforementioned advance of short-wave troughs farther west. At the surface, a rather deep (990 mb) surface cyclone is currently analyzed near the ND/SD/MN border intersection, with a cold front extending southward across the Middle Missouri Valley into Kansas. This boundary, and the advance of the upper trough, may support isolated late afternoon strong/potentially severe convective development across eastern Iowa/northwestern Illinois. Elsewhere, showers and scattered thunderstorms are expected to evolve across the Four Corners states ahead of the aforementioned upper trough, and overnight thunder may evolve within an area of broad/weak QG ascent over parts of the Lower Mississippi and Tennessee Valleys. Severe weather is not expected in these areas. ...Eastern Iowa/northern Illinois/southern Wisconsin vicinity... Low-level moisture remains a primary uncertainty today, with respect to potential strong/severe storm development. Dewpoints remain in the upper 30s/low 40s across the Iowa/Illinois area, where model forecast soundings -- particularly the RAP -- have consistently indicated upper 40s to low 50s dewpoints by late afternoon. This degree of moistening still appears to be a bit aggressive, with middle to upper 40s largely anticipated. With that said, very cold air aloft/steep lapse rates will continue to overspread this region, and the deep-layer wind field is conditionally quite supportive of severe/supercell storms. At this time, we will maintain MRGL risk and all-hazard, low-probability outlook. A couple of storms may develop by late afternoon, in the eastern Iowa/northwestern Illinois vicinity, and then shift eastward/east-northeastward through early evening, before weakening. However, evolution of moisture through the day will be closely watched, as the more aggressive RAP model solution -- should it appear more likely to occur -- would require consideration for an upgrade to the outlook at 20Z. ..Goss/Thornton.. 02/08/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1030 AM CST Thu Feb 08 2024 Valid 081630Z - 091200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM FAR EASTERN IOWA EASTWARD TO SOUTHWESTERN PARTS OF LAKE MICHIGAN... ...SUMMARY... A few strong/severe thunderstorms remain possible this afternoon through early evening across parts of far eastern Iowa, northern Illinois, far southern Wisconsin, and the southern Lake Michigan vicinity. ...Synopsis... A mid-level short-wave trough now crossing the Middle Missouri Valley/central Plains will continue progressing northeastward today and tonight, while a second feature now in the vicinity of the Lower Colorado Valley shifts eastward through the period. Meanwhile, upper ridging over the East will be shunted progressively eastward by the aforementioned advance of short-wave troughs farther west. At the surface, a rather deep (990 mb) surface cyclone is currently analyzed near the ND/SD/MN border intersection, with a cold front extending southward across the Middle Missouri Valley into Kansas. This boundary, and the advance of the upper trough, may support isolated late afternoon strong/potentially severe convective development across eastern Iowa/northwestern Illinois. Elsewhere, showers and scattered thunderstorms are expected to evolve across the Four Corners states ahead of the aforementioned upper trough, and overnight thunder may evolve within an area of broad/weak QG ascent over parts of the Lower Mississippi and Tennessee Valleys. Severe weather is not expected in these areas. ...Eastern Iowa/northern Illinois/southern Wisconsin vicinity... Low-level moisture remains a primary uncertainty today, with respect to potential strong/severe storm development. Dewpoints remain in the upper 30s/low 40s across the Iowa/Illinois area, where model forecast soundings -- particularly the RAP -- have consistently indicated upper 40s to low 50s dewpoints by late afternoon. This degree of moistening still appears to be a bit aggressive, with middle to upper 40s largely anticipated. With that said, very cold air aloft/steep lapse rates will continue to overspread this region, and the deep-layer wind field is conditionally quite supportive of severe/supercell storms. At this time, we will maintain MRGL risk and all-hazard, low-probability outlook. A couple of storms may develop by late afternoon, in the eastern Iowa/northwestern Illinois vicinity, and then shift eastward/east-northeastward through early evening, before weakening. However, evolution of moisture through the day will be closely watched, as the more aggressive RAP model solution -- should it appear more likely to occur -- would require consideration for an upgrade to the outlook at 20Z. ..Goss/Thornton.. 02/08/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1030 AM CST Thu Feb 08 2024 Valid 081630Z - 091200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM FAR EASTERN IOWA EASTWARD TO SOUTHWESTERN PARTS OF LAKE MICHIGAN... ...SUMMARY... A few strong/severe thunderstorms remain possible this afternoon through early evening across parts of far eastern Iowa, northern Illinois, far southern Wisconsin, and the southern Lake Michigan vicinity. ...Synopsis... A mid-level short-wave trough now crossing the Middle Missouri Valley/central Plains will continue progressing northeastward today and tonight, while a second feature now in the vicinity of the Lower Colorado Valley shifts eastward through the period. Meanwhile, upper ridging over the East will be shunted progressively eastward by the aforementioned advance of short-wave troughs farther west. At the surface, a rather deep (990 mb) surface cyclone is currently analyzed near the ND/SD/MN border intersection, with a cold front extending southward across the Middle Missouri Valley into Kansas. This boundary, and the advance of the upper trough, may support isolated late afternoon strong/potentially severe convective development across eastern Iowa/northwestern Illinois. Elsewhere, showers and scattered thunderstorms are expected to evolve across the Four Corners states ahead of the aforementioned upper trough, and overnight thunder may evolve within an area of broad/weak QG ascent over parts of the Lower Mississippi and Tennessee Valleys. Severe weather is not expected in these areas. ...Eastern Iowa/northern Illinois/southern Wisconsin vicinity... Low-level moisture remains a primary uncertainty today, with respect to potential strong/severe storm development. Dewpoints remain in the upper 30s/low 40s across the Iowa/Illinois area, where model forecast soundings -- particularly the RAP -- have consistently indicated upper 40s to low 50s dewpoints by late afternoon. This degree of moistening still appears to be a bit aggressive, with middle to upper 40s largely anticipated. With that said, very cold air aloft/steep lapse rates will continue to overspread this region, and the deep-layer wind field is conditionally quite supportive of severe/supercell storms. At this time, we will maintain MRGL risk and all-hazard, low-probability outlook. A couple of storms may develop by late afternoon, in the eastern Iowa/northwestern Illinois vicinity, and then shift eastward/east-northeastward through early evening, before weakening. However, evolution of moisture through the day will be closely watched, as the more aggressive RAP model solution -- should it appear more likely to occur -- would require consideration for an upgrade to the outlook at 20Z. ..Goss/Thornton.. 02/08/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1030 AM CST Thu Feb 08 2024 Valid 081630Z - 091200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM FAR EASTERN IOWA EASTWARD TO SOUTHWESTERN PARTS OF LAKE MICHIGAN... ...SUMMARY... A few strong/severe thunderstorms remain possible this afternoon through early evening across parts of far eastern Iowa, northern Illinois, far southern Wisconsin, and the southern Lake Michigan vicinity. ...Synopsis... A mid-level short-wave trough now crossing the Middle Missouri Valley/central Plains will continue progressing northeastward today and tonight, while a second feature now in the vicinity of the Lower Colorado Valley shifts eastward through the period. Meanwhile, upper ridging over the East will be shunted progressively eastward by the aforementioned advance of short-wave troughs farther west. At the surface, a rather deep (990 mb) surface cyclone is currently analyzed near the ND/SD/MN border intersection, with a cold front extending southward across the Middle Missouri Valley into Kansas. This boundary, and the advance of the upper trough, may support isolated late afternoon strong/potentially severe convective development across eastern Iowa/northwestern Illinois. Elsewhere, showers and scattered thunderstorms are expected to evolve across the Four Corners states ahead of the aforementioned upper trough, and overnight thunder may evolve within an area of broad/weak QG ascent over parts of the Lower Mississippi and Tennessee Valleys. Severe weather is not expected in these areas. ...Eastern Iowa/northern Illinois/southern Wisconsin vicinity... Low-level moisture remains a primary uncertainty today, with respect to potential strong/severe storm development. Dewpoints remain in the upper 30s/low 40s across the Iowa/Illinois area, where model forecast soundings -- particularly the RAP -- have consistently indicated upper 40s to low 50s dewpoints by late afternoon. This degree of moistening still appears to be a bit aggressive, with middle to upper 40s largely anticipated. With that said, very cold air aloft/steep lapse rates will continue to overspread this region, and the deep-layer wind field is conditionally quite supportive of severe/supercell storms. At this time, we will maintain MRGL risk and all-hazard, low-probability outlook. A couple of storms may develop by late afternoon, in the eastern Iowa/northwestern Illinois vicinity, and then shift eastward/east-northeastward through early evening, before weakening. However, evolution of moisture through the day will be closely watched, as the more aggressive RAP model solution -- should it appear more likely to occur -- would require consideration for an upgrade to the outlook at 20Z. ..Goss/Thornton.. 02/08/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0650 AM CST Thu Feb 08 2024 Valid 081300Z - 091200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF EASTERN IOWA...SOUTHERN WISCONSIN...AND NORTHERN ILLINOIS... ...SUMMARY... Isolated severe thunderstorms are possible this afternoon through early evening across parts of far eastern Iowa, northern Illinois, far southern Wisconsin, and the southern Lake Michigan vicinity. ...Midwest/Upper Mississippi Valley/Lake Michigan vicinity... Steady height falls will occur preceding the eastward advancement of an upper trough currently across the northern/central Great Plains, with this trough reaching the Upper Great Lakes/northern Ontario tonight. Strengthening deep-layer southwesterly winds (80+ kt 500 mb) will overspread much of the Midwest/Lake Michigan vicinity. A surface low will progress northeastward across northern Minnesota toward northern Ontario, as a cold front sweeps eastward across the Upper Midwest and Upper Great Lakes. Some pre-frontal moistening is expected today, but overall limited moisture quality should preclude a greater and more certain severe risk. Low-topped thunderstorms are expected to develop, at least on an isolated basis, by mid/late afternoon initially across eastern Iowa and Wisconsin/northwest Illinois near the front, within a zone of modest destabilization (below 500 J/kg MLCAPE) but minimal inhibition. While low-level moisture will be rather limited, with surface dewpoints should generally no higher than 50 F around peak heating, the steepness of lapse rates (-25C around 500mb) could support some severe-caliber surface-based low-topped storms (tops generally 25,000 ft or below), with strong wind profiles/low-level hodograph curvature supportive of rotating storms. Hail and locally damaging winds will be possible, along with some tornado risk. Storms should persist, and potentially remain strong/locally severe, northeastward toward the southern Lake Michigan vicinity through early/mid-evening, before nocturnal boundary layer/cool lake influences lead to a diminishing convective intensity by late evening. ..Guyer/Leitman.. 02/08/2024 Read more