Severe Storms

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Wed Jul 16 2025 Valid 161630Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MIDWEST AND CENTRAL HIGH PLAINS... ...SUMMARY... Scattered severe thunderstorms are possible this afternoon and evening over parts of the Midwest and central High Plains. ...Midwest/Great Lakes... Late morning radar/satellite imagery shows an MCV over northeast IA co-located with a 1007-mb surface low. A front is draped from northeast to southwest and is forecast to gradually push eastward during the day. The frontal segment east-northeast of the low will remain quasi-stationary and serve as the northern delimiter of a surface-based warm sector. Continued heating of a moist boundary layer will contribute to 1000-2500 J/kg of MLCAPE across central WI into northern/central IL. The modestly enhanced low/mid-level winds associated with the MCV will yield 30-40 kt of effective shear---supporting rotation with a few of the stronger updrafts this afternoon. Semi-discrete thunderstorms developing in a north-south band will likely continue to intensify as ascent overspreads the warm sector over WI and far northern IL. A few supercells are possible with an attendant risk for all hazards. With time late this afternoon and evening, gradual upscale growth into a bowing cluster should occur, with a greater risk for severe/damaging winds towards Lake Michigan and parts of southern Lower MI. ...Central High Plains to Northern Missouri... Indications late this morning are that a convectively reinforced surface front will become stationary across KS into eastern CO with moist, upslope flow into the central High Plains north of the boundary. The southern periphery of stronger mid-level westerly flow will glance the central High Plains where strongly veering flow will result in deep-layer shear supporting storm organization. Although heating will be partially thwarted by persistent low-level cloud cover through at least the early afternoon, sufficient heating is expected to result in scattered to widespread thunderstorms eventually developing during the late afternoon. A few supercells are possible with an accompanying threat for large hail and localized severe gusts. As storm coverage increases, upscale growth into an organized cluster is probable during the evening. Severe gusts will likely become the primary hazard during the evening as the mode becomes more linear and outflow dominant. Farther east across KS into northern MO, isolated convection may develop through peak afternoon heating along the front. While deep-layer shear is forecast to remain fairly modest, strong instability and steep mid-level lapse rates could still support occasional severe hail/wind with the more robust cores that can be sustained. Additional convection may develop along/north of the front this evening in a low-level warm advection regime, while also posing an isolated severe threat. ...Ohio Valley/Mid-Atlantic... A couple of MCVs will focus scattered strong to locally severe thunderstorms mainly this afternoon and early evening. Relatively weak lapse rates and modest deep-layer shear will tend to limit storm organization. Nonetheless, sporadic and isolated bouts of strong to damaging gusts are possible with the stronger thunderstorms through early evening. ...Central Gulf Coast... Modest strengthening of the low-level wind field is expected as a weak tropical disturbance migrates westward over the northern Gulf of America. However, model guidance shows hodographs generally remaining diminutive in size, implying disorganized storm modes (mainly outflow dominant structures in the form of bands and small clusters). ..Smith/Lyons.. 07/16/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Wed Jul 16 2025 Valid 161630Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MIDWEST AND CENTRAL HIGH PLAINS... ...SUMMARY... Scattered severe thunderstorms are possible this afternoon and evening over parts of the Midwest and central High Plains. ...Midwest/Great Lakes... Late morning radar/satellite imagery shows an MCV over northeast IA co-located with a 1007-mb surface low. A front is draped from northeast to southwest and is forecast to gradually push eastward during the day. The frontal segment east-northeast of the low will remain quasi-stationary and serve as the northern delimiter of a surface-based warm sector. Continued heating of a moist boundary layer will contribute to 1000-2500 J/kg of MLCAPE across central WI into northern/central IL. The modestly enhanced low/mid-level winds associated with the MCV will yield 30-40 kt of effective shear---supporting rotation with a few of the stronger updrafts this afternoon. Semi-discrete thunderstorms developing in a north-south band will likely continue to intensify as ascent overspreads the warm sector over WI and far northern IL. A few supercells are possible with an attendant risk for all hazards. With time late this afternoon and evening, gradual upscale growth into a bowing cluster should occur, with a greater risk for severe/damaging winds towards Lake Michigan and parts of southern Lower MI. ...Central High Plains to Northern Missouri... Indications late this morning are that a convectively reinforced surface front will become stationary across KS into eastern CO with moist, upslope flow into the central High Plains north of the boundary. The southern periphery of stronger mid-level westerly flow will glance the central High Plains where strongly veering flow will result in deep-layer shear supporting storm organization. Although heating will be partially thwarted by persistent low-level cloud cover through at least the early afternoon, sufficient heating is expected to result in scattered to widespread thunderstorms eventually developing during the late afternoon. A few supercells are possible with an accompanying threat for large hail and localized severe gusts. As storm coverage increases, upscale growth into an organized cluster is probable during the evening. Severe gusts will likely become the primary hazard during the evening as the mode becomes more linear and outflow dominant. Farther east across KS into northern MO, isolated convection may develop through peak afternoon heating along the front. While deep-layer shear is forecast to remain fairly modest, strong instability and steep mid-level lapse rates could still support occasional severe hail/wind with the more robust cores that can be sustained. Additional convection may develop along/north of the front this evening in a low-level warm advection regime, while also posing an isolated severe threat. ...Ohio Valley/Mid-Atlantic... A couple of MCVs will focus scattered strong to locally severe thunderstorms mainly this afternoon and early evening. Relatively weak lapse rates and modest deep-layer shear will tend to limit storm organization. Nonetheless, sporadic and isolated bouts of strong to damaging gusts are possible with the stronger thunderstorms through early evening. ...Central Gulf Coast... Modest strengthening of the low-level wind field is expected as a weak tropical disturbance migrates westward over the northern Gulf of America. However, model guidance shows hodographs generally remaining diminutive in size, implying disorganized storm modes (mainly outflow dominant structures in the form of bands and small clusters). ..Smith/Lyons.. 07/16/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Wed Jul 16 2025 Valid 161630Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MIDWEST AND CENTRAL HIGH PLAINS... ...SUMMARY... Scattered severe thunderstorms are possible this afternoon and evening over parts of the Midwest and central High Plains. ...Midwest/Great Lakes... Late morning radar/satellite imagery shows an MCV over northeast IA co-located with a 1007-mb surface low. A front is draped from northeast to southwest and is forecast to gradually push eastward during the day. The frontal segment east-northeast of the low will remain quasi-stationary and serve as the northern delimiter of a surface-based warm sector. Continued heating of a moist boundary layer will contribute to 1000-2500 J/kg of MLCAPE across central WI into northern/central IL. The modestly enhanced low/mid-level winds associated with the MCV will yield 30-40 kt of effective shear---supporting rotation with a few of the stronger updrafts this afternoon. Semi-discrete thunderstorms developing in a north-south band will likely continue to intensify as ascent overspreads the warm sector over WI and far northern IL. A few supercells are possible with an attendant risk for all hazards. With time late this afternoon and evening, gradual upscale growth into a bowing cluster should occur, with a greater risk for severe/damaging winds towards Lake Michigan and parts of southern Lower MI. ...Central High Plains to Northern Missouri... Indications late this morning are that a convectively reinforced surface front will become stationary across KS into eastern CO with moist, upslope flow into the central High Plains north of the boundary. The southern periphery of stronger mid-level westerly flow will glance the central High Plains where strongly veering flow will result in deep-layer shear supporting storm organization. Although heating will be partially thwarted by persistent low-level cloud cover through at least the early afternoon, sufficient heating is expected to result in scattered to widespread thunderstorms eventually developing during the late afternoon. A few supercells are possible with an accompanying threat for large hail and localized severe gusts. As storm coverage increases, upscale growth into an organized cluster is probable during the evening. Severe gusts will likely become the primary hazard during the evening as the mode becomes more linear and outflow dominant. Farther east across KS into northern MO, isolated convection may develop through peak afternoon heating along the front. While deep-layer shear is forecast to remain fairly modest, strong instability and steep mid-level lapse rates could still support occasional severe hail/wind with the more robust cores that can be sustained. Additional convection may develop along/north of the front this evening in a low-level warm advection regime, while also posing an isolated severe threat. ...Ohio Valley/Mid-Atlantic... A couple of MCVs will focus scattered strong to locally severe thunderstorms mainly this afternoon and early evening. Relatively weak lapse rates and modest deep-layer shear will tend to limit storm organization. Nonetheless, sporadic and isolated bouts of strong to damaging gusts are possible with the stronger thunderstorms through early evening. ...Central Gulf Coast... Modest strengthening of the low-level wind field is expected as a weak tropical disturbance migrates westward over the northern Gulf of America. However, model guidance shows hodographs generally remaining diminutive in size, implying disorganized storm modes (mainly outflow dominant structures in the form of bands and small clusters). ..Smith/Lyons.. 07/16/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Wed Jul 16 2025 Valid 161630Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MIDWEST AND CENTRAL HIGH PLAINS... ...SUMMARY... Scattered severe thunderstorms are possible this afternoon and evening over parts of the Midwest and central High Plains. ...Midwest/Great Lakes... Late morning radar/satellite imagery shows an MCV over northeast IA co-located with a 1007-mb surface low. A front is draped from northeast to southwest and is forecast to gradually push eastward during the day. The frontal segment east-northeast of the low will remain quasi-stationary and serve as the northern delimiter of a surface-based warm sector. Continued heating of a moist boundary layer will contribute to 1000-2500 J/kg of MLCAPE across central WI into northern/central IL. The modestly enhanced low/mid-level winds associated with the MCV will yield 30-40 kt of effective shear---supporting rotation with a few of the stronger updrafts this afternoon. Semi-discrete thunderstorms developing in a north-south band will likely continue to intensify as ascent overspreads the warm sector over WI and far northern IL. A few supercells are possible with an attendant risk for all hazards. With time late this afternoon and evening, gradual upscale growth into a bowing cluster should occur, with a greater risk for severe/damaging winds towards Lake Michigan and parts of southern Lower MI. ...Central High Plains to Northern Missouri... Indications late this morning are that a convectively reinforced surface front will become stationary across KS into eastern CO with moist, upslope flow into the central High Plains north of the boundary. The southern periphery of stronger mid-level westerly flow will glance the central High Plains where strongly veering flow will result in deep-layer shear supporting storm organization. Although heating will be partially thwarted by persistent low-level cloud cover through at least the early afternoon, sufficient heating is expected to result in scattered to widespread thunderstorms eventually developing during the late afternoon. A few supercells are possible with an accompanying threat for large hail and localized severe gusts. As storm coverage increases, upscale growth into an organized cluster is probable during the evening. Severe gusts will likely become the primary hazard during the evening as the mode becomes more linear and outflow dominant. Farther east across KS into northern MO, isolated convection may develop through peak afternoon heating along the front. While deep-layer shear is forecast to remain fairly modest, strong instability and steep mid-level lapse rates could still support occasional severe hail/wind with the more robust cores that can be sustained. Additional convection may develop along/north of the front this evening in a low-level warm advection regime, while also posing an isolated severe threat. ...Ohio Valley/Mid-Atlantic... A couple of MCVs will focus scattered strong to locally severe thunderstorms mainly this afternoon and early evening. Relatively weak lapse rates and modest deep-layer shear will tend to limit storm organization. Nonetheless, sporadic and isolated bouts of strong to damaging gusts are possible with the stronger thunderstorms through early evening. ...Central Gulf Coast... Modest strengthening of the low-level wind field is expected as a weak tropical disturbance migrates westward over the northern Gulf of America. However, model guidance shows hodographs generally remaining diminutive in size, implying disorganized storm modes (mainly outflow dominant structures in the form of bands and small clusters). ..Smith/Lyons.. 07/16/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Wed Jul 16 2025 Valid 161630Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MIDWEST AND CENTRAL HIGH PLAINS... ...SUMMARY... Scattered severe thunderstorms are possible this afternoon and evening over parts of the Midwest and central High Plains. ...Midwest/Great Lakes... Late morning radar/satellite imagery shows an MCV over northeast IA co-located with a 1007-mb surface low. A front is draped from northeast to southwest and is forecast to gradually push eastward during the day. The frontal segment east-northeast of the low will remain quasi-stationary and serve as the northern delimiter of a surface-based warm sector. Continued heating of a moist boundary layer will contribute to 1000-2500 J/kg of MLCAPE across central WI into northern/central IL. The modestly enhanced low/mid-level winds associated with the MCV will yield 30-40 kt of effective shear---supporting rotation with a few of the stronger updrafts this afternoon. Semi-discrete thunderstorms developing in a north-south band will likely continue to intensify as ascent overspreads the warm sector over WI and far northern IL. A few supercells are possible with an attendant risk for all hazards. With time late this afternoon and evening, gradual upscale growth into a bowing cluster should occur, with a greater risk for severe/damaging winds towards Lake Michigan and parts of southern Lower MI. ...Central High Plains to Northern Missouri... Indications late this morning are that a convectively reinforced surface front will become stationary across KS into eastern CO with moist, upslope flow into the central High Plains north of the boundary. The southern periphery of stronger mid-level westerly flow will glance the central High Plains where strongly veering flow will result in deep-layer shear supporting storm organization. Although heating will be partially thwarted by persistent low-level cloud cover through at least the early afternoon, sufficient heating is expected to result in scattered to widespread thunderstorms eventually developing during the late afternoon. A few supercells are possible with an accompanying threat for large hail and localized severe gusts. As storm coverage increases, upscale growth into an organized cluster is probable during the evening. Severe gusts will likely become the primary hazard during the evening as the mode becomes more linear and outflow dominant. Farther east across KS into northern MO, isolated convection may develop through peak afternoon heating along the front. While deep-layer shear is forecast to remain fairly modest, strong instability and steep mid-level lapse rates could still support occasional severe hail/wind with the more robust cores that can be sustained. Additional convection may develop along/north of the front this evening in a low-level warm advection regime, while also posing an isolated severe threat. ...Ohio Valley/Mid-Atlantic... A couple of MCVs will focus scattered strong to locally severe thunderstorms mainly this afternoon and early evening. Relatively weak lapse rates and modest deep-layer shear will tend to limit storm organization. Nonetheless, sporadic and isolated bouts of strong to damaging gusts are possible with the stronger thunderstorms through early evening. ...Central Gulf Coast... Modest strengthening of the low-level wind field is expected as a weak tropical disturbance migrates westward over the northern Gulf of America. However, model guidance shows hodographs generally remaining diminutive in size, implying disorganized storm modes (mainly outflow dominant structures in the form of bands and small clusters). ..Smith/Lyons.. 07/16/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Wed Jul 16 2025 Valid 161630Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MIDWEST AND CENTRAL HIGH PLAINS... ...SUMMARY... Scattered severe thunderstorms are possible this afternoon and evening over parts of the Midwest and central High Plains. ...Midwest/Great Lakes... Late morning radar/satellite imagery shows an MCV over northeast IA co-located with a 1007-mb surface low. A front is draped from northeast to southwest and is forecast to gradually push eastward during the day. The frontal segment east-northeast of the low will remain quasi-stationary and serve as the northern delimiter of a surface-based warm sector. Continued heating of a moist boundary layer will contribute to 1000-2500 J/kg of MLCAPE across central WI into northern/central IL. The modestly enhanced low/mid-level winds associated with the MCV will yield 30-40 kt of effective shear---supporting rotation with a few of the stronger updrafts this afternoon. Semi-discrete thunderstorms developing in a north-south band will likely continue to intensify as ascent overspreads the warm sector over WI and far northern IL. A few supercells are possible with an attendant risk for all hazards. With time late this afternoon and evening, gradual upscale growth into a bowing cluster should occur, with a greater risk for severe/damaging winds towards Lake Michigan and parts of southern Lower MI. ...Central High Plains to Northern Missouri... Indications late this morning are that a convectively reinforced surface front will become stationary across KS into eastern CO with moist, upslope flow into the central High Plains north of the boundary. The southern periphery of stronger mid-level westerly flow will glance the central High Plains where strongly veering flow will result in deep-layer shear supporting storm organization. Although heating will be partially thwarted by persistent low-level cloud cover through at least the early afternoon, sufficient heating is expected to result in scattered to widespread thunderstorms eventually developing during the late afternoon. A few supercells are possible with an accompanying threat for large hail and localized severe gusts. As storm coverage increases, upscale growth into an organized cluster is probable during the evening. Severe gusts will likely become the primary hazard during the evening as the mode becomes more linear and outflow dominant. Farther east across KS into northern MO, isolated convection may develop through peak afternoon heating along the front. While deep-layer shear is forecast to remain fairly modest, strong instability and steep mid-level lapse rates could still support occasional severe hail/wind with the more robust cores that can be sustained. Additional convection may develop along/north of the front this evening in a low-level warm advection regime, while also posing an isolated severe threat. ...Ohio Valley/Mid-Atlantic... A couple of MCVs will focus scattered strong to locally severe thunderstorms mainly this afternoon and early evening. Relatively weak lapse rates and modest deep-layer shear will tend to limit storm organization. Nonetheless, sporadic and isolated bouts of strong to damaging gusts are possible with the stronger thunderstorms through early evening. ...Central Gulf Coast... Modest strengthening of the low-level wind field is expected as a weak tropical disturbance migrates westward over the northern Gulf of America. However, model guidance shows hodographs generally remaining diminutive in size, implying disorganized storm modes (mainly outflow dominant structures in the form of bands and small clusters). ..Smith/Lyons.. 07/16/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Wed Jul 16 2025 Valid 161630Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MIDWEST AND CENTRAL HIGH PLAINS... ...SUMMARY... Scattered severe thunderstorms are possible this afternoon and evening over parts of the Midwest and central High Plains. ...Midwest/Great Lakes... Late morning radar/satellite imagery shows an MCV over northeast IA co-located with a 1007-mb surface low. A front is draped from northeast to southwest and is forecast to gradually push eastward during the day. The frontal segment east-northeast of the low will remain quasi-stationary and serve as the northern delimiter of a surface-based warm sector. Continued heating of a moist boundary layer will contribute to 1000-2500 J/kg of MLCAPE across central WI into northern/central IL. The modestly enhanced low/mid-level winds associated with the MCV will yield 30-40 kt of effective shear---supporting rotation with a few of the stronger updrafts this afternoon. Semi-discrete thunderstorms developing in a north-south band will likely continue to intensify as ascent overspreads the warm sector over WI and far northern IL. A few supercells are possible with an attendant risk for all hazards. With time late this afternoon and evening, gradual upscale growth into a bowing cluster should occur, with a greater risk for severe/damaging winds towards Lake Michigan and parts of southern Lower MI. ...Central High Plains to Northern Missouri... Indications late this morning are that a convectively reinforced surface front will become stationary across KS into eastern CO with moist, upslope flow into the central High Plains north of the boundary. The southern periphery of stronger mid-level westerly flow will glance the central High Plains where strongly veering flow will result in deep-layer shear supporting storm organization. Although heating will be partially thwarted by persistent low-level cloud cover through at least the early afternoon, sufficient heating is expected to result in scattered to widespread thunderstorms eventually developing during the late afternoon. A few supercells are possible with an accompanying threat for large hail and localized severe gusts. As storm coverage increases, upscale growth into an organized cluster is probable during the evening. Severe gusts will likely become the primary hazard during the evening as the mode becomes more linear and outflow dominant. Farther east across KS into northern MO, isolated convection may develop through peak afternoon heating along the front. While deep-layer shear is forecast to remain fairly modest, strong instability and steep mid-level lapse rates could still support occasional severe hail/wind with the more robust cores that can be sustained. Additional convection may develop along/north of the front this evening in a low-level warm advection regime, while also posing an isolated severe threat. ...Ohio Valley/Mid-Atlantic... A couple of MCVs will focus scattered strong to locally severe thunderstorms mainly this afternoon and early evening. Relatively weak lapse rates and modest deep-layer shear will tend to limit storm organization. Nonetheless, sporadic and isolated bouts of strong to damaging gusts are possible with the stronger thunderstorms through early evening. ...Central Gulf Coast... Modest strengthening of the low-level wind field is expected as a weak tropical disturbance migrates westward over the northern Gulf of America. However, model guidance shows hodographs generally remaining diminutive in size, implying disorganized storm modes (mainly outflow dominant structures in the form of bands and small clusters). ..Smith/Lyons.. 07/16/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Wed Jul 16 2025 Valid 161630Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MIDWEST AND CENTRAL HIGH PLAINS... ...SUMMARY... Scattered severe thunderstorms are possible this afternoon and evening over parts of the Midwest and central High Plains. ...Midwest/Great Lakes... Late morning radar/satellite imagery shows an MCV over northeast IA co-located with a 1007-mb surface low. A front is draped from northeast to southwest and is forecast to gradually push eastward during the day. The frontal segment east-northeast of the low will remain quasi-stationary and serve as the northern delimiter of a surface-based warm sector. Continued heating of a moist boundary layer will contribute to 1000-2500 J/kg of MLCAPE across central WI into northern/central IL. The modestly enhanced low/mid-level winds associated with the MCV will yield 30-40 kt of effective shear---supporting rotation with a few of the stronger updrafts this afternoon. Semi-discrete thunderstorms developing in a north-south band will likely continue to intensify as ascent overspreads the warm sector over WI and far northern IL. A few supercells are possible with an attendant risk for all hazards. With time late this afternoon and evening, gradual upscale growth into a bowing cluster should occur, with a greater risk for severe/damaging winds towards Lake Michigan and parts of southern Lower MI. ...Central High Plains to Northern Missouri... Indications late this morning are that a convectively reinforced surface front will become stationary across KS into eastern CO with moist, upslope flow into the central High Plains north of the boundary. The southern periphery of stronger mid-level westerly flow will glance the central High Plains where strongly veering flow will result in deep-layer shear supporting storm organization. Although heating will be partially thwarted by persistent low-level cloud cover through at least the early afternoon, sufficient heating is expected to result in scattered to widespread thunderstorms eventually developing during the late afternoon. A few supercells are possible with an accompanying threat for large hail and localized severe gusts. As storm coverage increases, upscale growth into an organized cluster is probable during the evening. Severe gusts will likely become the primary hazard during the evening as the mode becomes more linear and outflow dominant. Farther east across KS into northern MO, isolated convection may develop through peak afternoon heating along the front. While deep-layer shear is forecast to remain fairly modest, strong instability and steep mid-level lapse rates could still support occasional severe hail/wind with the more robust cores that can be sustained. Additional convection may develop along/north of the front this evening in a low-level warm advection regime, while also posing an isolated severe threat. ...Ohio Valley/Mid-Atlantic... A couple of MCVs will focus scattered strong to locally severe thunderstorms mainly this afternoon and early evening. Relatively weak lapse rates and modest deep-layer shear will tend to limit storm organization. Nonetheless, sporadic and isolated bouts of strong to damaging gusts are possible with the stronger thunderstorms through early evening. ...Central Gulf Coast... Modest strengthening of the low-level wind field is expected as a weak tropical disturbance migrates westward over the northern Gulf of America. However, model guidance shows hodographs generally remaining diminutive in size, implying disorganized storm modes (mainly outflow dominant structures in the form of bands and small clusters). ..Smith/Lyons.. 07/16/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Wed Jul 16 2025 Valid 161630Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MIDWEST AND CENTRAL HIGH PLAINS... ...SUMMARY... Scattered severe thunderstorms are possible this afternoon and evening over parts of the Midwest and central High Plains. ...Midwest/Great Lakes... Late morning radar/satellite imagery shows an MCV over northeast IA co-located with a 1007-mb surface low. A front is draped from northeast to southwest and is forecast to gradually push eastward during the day. The frontal segment east-northeast of the low will remain quasi-stationary and serve as the northern delimiter of a surface-based warm sector. Continued heating of a moist boundary layer will contribute to 1000-2500 J/kg of MLCAPE across central WI into northern/central IL. The modestly enhanced low/mid-level winds associated with the MCV will yield 30-40 kt of effective shear---supporting rotation with a few of the stronger updrafts this afternoon. Semi-discrete thunderstorms developing in a north-south band will likely continue to intensify as ascent overspreads the warm sector over WI and far northern IL. A few supercells are possible with an attendant risk for all hazards. With time late this afternoon and evening, gradual upscale growth into a bowing cluster should occur, with a greater risk for severe/damaging winds towards Lake Michigan and parts of southern Lower MI. ...Central High Plains to Northern Missouri... Indications late this morning are that a convectively reinforced surface front will become stationary across KS into eastern CO with moist, upslope flow into the central High Plains north of the boundary. The southern periphery of stronger mid-level westerly flow will glance the central High Plains where strongly veering flow will result in deep-layer shear supporting storm organization. Although heating will be partially thwarted by persistent low-level cloud cover through at least the early afternoon, sufficient heating is expected to result in scattered to widespread thunderstorms eventually developing during the late afternoon. A few supercells are possible with an accompanying threat for large hail and localized severe gusts. As storm coverage increases, upscale growth into an organized cluster is probable during the evening. Severe gusts will likely become the primary hazard during the evening as the mode becomes more linear and outflow dominant. Farther east across KS into northern MO, isolated convection may develop through peak afternoon heating along the front. While deep-layer shear is forecast to remain fairly modest, strong instability and steep mid-level lapse rates could still support occasional severe hail/wind with the more robust cores that can be sustained. Additional convection may develop along/north of the front this evening in a low-level warm advection regime, while also posing an isolated severe threat. ...Ohio Valley/Mid-Atlantic... A couple of MCVs will focus scattered strong to locally severe thunderstorms mainly this afternoon and early evening. Relatively weak lapse rates and modest deep-layer shear will tend to limit storm organization. Nonetheless, sporadic and isolated bouts of strong to damaging gusts are possible with the stronger thunderstorms through early evening. ...Central Gulf Coast... Modest strengthening of the low-level wind field is expected as a weak tropical disturbance migrates westward over the northern Gulf of America. However, model guidance shows hodographs generally remaining diminutive in size, implying disorganized storm modes (mainly outflow dominant structures in the form of bands and small clusters). ..Smith/Lyons.. 07/16/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Wed Jul 16 2025 Valid 161630Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MIDWEST AND CENTRAL HIGH PLAINS... ...SUMMARY... Scattered severe thunderstorms are possible this afternoon and evening over parts of the Midwest and central High Plains. ...Midwest/Great Lakes... Late morning radar/satellite imagery shows an MCV over northeast IA co-located with a 1007-mb surface low. A front is draped from northeast to southwest and is forecast to gradually push eastward during the day. The frontal segment east-northeast of the low will remain quasi-stationary and serve as the northern delimiter of a surface-based warm sector. Continued heating of a moist boundary layer will contribute to 1000-2500 J/kg of MLCAPE across central WI into northern/central IL. The modestly enhanced low/mid-level winds associated with the MCV will yield 30-40 kt of effective shear---supporting rotation with a few of the stronger updrafts this afternoon. Semi-discrete thunderstorms developing in a north-south band will likely continue to intensify as ascent overspreads the warm sector over WI and far northern IL. A few supercells are possible with an attendant risk for all hazards. With time late this afternoon and evening, gradual upscale growth into a bowing cluster should occur, with a greater risk for severe/damaging winds towards Lake Michigan and parts of southern Lower MI. ...Central High Plains to Northern Missouri... Indications late this morning are that a convectively reinforced surface front will become stationary across KS into eastern CO with moist, upslope flow into the central High Plains north of the boundary. The southern periphery of stronger mid-level westerly flow will glance the central High Plains where strongly veering flow will result in deep-layer shear supporting storm organization. Although heating will be partially thwarted by persistent low-level cloud cover through at least the early afternoon, sufficient heating is expected to result in scattered to widespread thunderstorms eventually developing during the late afternoon. A few supercells are possible with an accompanying threat for large hail and localized severe gusts. As storm coverage increases, upscale growth into an organized cluster is probable during the evening. Severe gusts will likely become the primary hazard during the evening as the mode becomes more linear and outflow dominant. Farther east across KS into northern MO, isolated convection may develop through peak afternoon heating along the front. While deep-layer shear is forecast to remain fairly modest, strong instability and steep mid-level lapse rates could still support occasional severe hail/wind with the more robust cores that can be sustained. Additional convection may develop along/north of the front this evening in a low-level warm advection regime, while also posing an isolated severe threat. ...Ohio Valley/Mid-Atlantic... A couple of MCVs will focus scattered strong to locally severe thunderstorms mainly this afternoon and early evening. Relatively weak lapse rates and modest deep-layer shear will tend to limit storm organization. Nonetheless, sporadic and isolated bouts of strong to damaging gusts are possible with the stronger thunderstorms through early evening. ...Central Gulf Coast... Modest strengthening of the low-level wind field is expected as a weak tropical disturbance migrates westward over the northern Gulf of America. However, model guidance shows hodographs generally remaining diminutive in size, implying disorganized storm modes (mainly outflow dominant structures in the form of bands and small clusters). ..Smith/Lyons.. 07/16/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Wed Jul 16 2025 Valid 161630Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MIDWEST AND CENTRAL HIGH PLAINS... ...SUMMARY... Scattered severe thunderstorms are possible this afternoon and evening over parts of the Midwest and central High Plains. ...Midwest/Great Lakes... Late morning radar/satellite imagery shows an MCV over northeast IA co-located with a 1007-mb surface low. A front is draped from northeast to southwest and is forecast to gradually push eastward during the day. The frontal segment east-northeast of the low will remain quasi-stationary and serve as the northern delimiter of a surface-based warm sector. Continued heating of a moist boundary layer will contribute to 1000-2500 J/kg of MLCAPE across central WI into northern/central IL. The modestly enhanced low/mid-level winds associated with the MCV will yield 30-40 kt of effective shear---supporting rotation with a few of the stronger updrafts this afternoon. Semi-discrete thunderstorms developing in a north-south band will likely continue to intensify as ascent overspreads the warm sector over WI and far northern IL. A few supercells are possible with an attendant risk for all hazards. With time late this afternoon and evening, gradual upscale growth into a bowing cluster should occur, with a greater risk for severe/damaging winds towards Lake Michigan and parts of southern Lower MI. ...Central High Plains to Northern Missouri... Indications late this morning are that a convectively reinforced surface front will become stationary across KS into eastern CO with moist, upslope flow into the central High Plains north of the boundary. The southern periphery of stronger mid-level westerly flow will glance the central High Plains where strongly veering flow will result in deep-layer shear supporting storm organization. Although heating will be partially thwarted by persistent low-level cloud cover through at least the early afternoon, sufficient heating is expected to result in scattered to widespread thunderstorms eventually developing during the late afternoon. A few supercells are possible with an accompanying threat for large hail and localized severe gusts. As storm coverage increases, upscale growth into an organized cluster is probable during the evening. Severe gusts will likely become the primary hazard during the evening as the mode becomes more linear and outflow dominant. Farther east across KS into northern MO, isolated convection may develop through peak afternoon heating along the front. While deep-layer shear is forecast to remain fairly modest, strong instability and steep mid-level lapse rates could still support occasional severe hail/wind with the more robust cores that can be sustained. Additional convection may develop along/north of the front this evening in a low-level warm advection regime, while also posing an isolated severe threat. ...Ohio Valley/Mid-Atlantic... A couple of MCVs will focus scattered strong to locally severe thunderstorms mainly this afternoon and early evening. Relatively weak lapse rates and modest deep-layer shear will tend to limit storm organization. Nonetheless, sporadic and isolated bouts of strong to damaging gusts are possible with the stronger thunderstorms through early evening. ...Central Gulf Coast... Modest strengthening of the low-level wind field is expected as a weak tropical disturbance migrates westward over the northern Gulf of America. However, model guidance shows hodographs generally remaining diminutive in size, implying disorganized storm modes (mainly outflow dominant structures in the form of bands and small clusters). ..Smith/Lyons.. 07/16/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0730 AM CDT Wed Jul 16 2025 Valid 161300Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MIDWEST/GREAT LAKES AND CENTRAL HIGH PLAINS... ...SUMMARY... Scattered strong to severe thunderstorms are possible this afternoon and evening from parts of the central High Plains to the Great Lakes and Mid-Atlantic. ...Midwest/Great Lakes... A well-defined MCV is evident on radar/satellite imagery this morning over IA. This feature will drift east-northeastward today across the Midwest and Great Lakes, eventually reaching southern Ontario tonight. A related surface low will develop from IA to southern WI and Lake Michigan this afternoon/evening, with the primary synoptic front farther north in WI. Diurnal heating of a rather moist low-level airmass will likely yield around 1000-2500 J/kg of MLCAPE across southern WI into northern/central IL (locally stronger with southward extent). The modestly enhanced low/mid-level winds associated with the MCV should support around 30-40 kt of deep-layer shear, sufficient for organized severe thunderstorms. Current expectations are for a band of semi-discrete thunderstorms to develop across eastern IA into northern IL and southern/central WI by early to mid afternoon as large-scale ascent attendant to the MCV overspreads the destabilizing warm sector. Some of this activity could be supercellular initially and pose a threat for isolated severe hail along with damaging winds. With time late this afternoon and evening, gradual upscale growth into a bowing cluster should occur, with a greater risk for severe/damaging winds towards Lake Michigan and parts of southern Lower MI. Although low-level flow and related shear is not forecast to become overly strong this afternoon, it should be sufficient for some low-level updraft rotation and perhaps a few tornadoes, particularly across parts of southern WI/northern IL where semi-discrete convection may occur. ...Ohio Valley/Mid-Atlantic... A weak mid-level shortwave trough located over the OH Valley this morning will advance northeastward today to the northern Mid-Atlantic/NY. Recent visible satellite imagery this morning shows considerable cloud cover present with this feature, along with some low clouds downstream. Even so, filtered daytime heating of a seasonably moist airmass should support the development of weak to locally moderate instability by this afternoon. Poor lapse rates aloft may tend to inhibit stronger updrafts to some extent, but marginal deep-layer shear (generally around 20-30 kt) should still support some degree of convective organization. Loosely organized clusters and occasional cells may pose an isolated threat for damaging winds as they spread generally east-northeastward across parts of the OH Valley and Mid-Atlantic this afternoon/evening. Confidence in a more concentrated corridor of damaging winds remains too low to include greater severe probabilities at this time. ...Central Plains to Northern Missouri... A convectively reinforced surface front should stall by this afternoon across KS into eastern CO, with a modest low-level upslope flow regime occurring across the Front Range/central High Plains. On the southern periphery of an upper trough moving eastward over the northern/central Plains, thunderstorms should develop by early afternoon over the higher terrain of the central Rockies. This convection is forecast to move eastward into the adjacent High Plains through the rest of the afternoon, and continuing through the evening. The post-frontal airmass should only modestly destabilize, but enough instability and the presence of steepened lapse rates aloft are forecast to support robust updrafts. Weak low-level flow veering to westerly and gradually strengthening with height at mid/upper levels will likely foster around 35-45 kt of deep-layer shear. This will easily support supercells and associated large hail threat with the initial development. Some potential for upscale growth into a loosely organized cluster is possible across southeast CO and vicinity this evening along/near the stalled surface front. If this occurs, then severe winds would become the primary risk. Farther east across KS into northern MO, isolated convection may develop through peak afternoon heating along the front. While deep-layer shear is forecast to remain fairly modest, strong instability and steep mid-level lapse rates could still support occasional severe hail/wind with the more robust cores that can be sustained. Additional convection may develop along/north of the front this evening in a low-level warm advection regime, while also posing an isolated severe threat. ...Central Gulf Coast... Convection offshore from the central Gulf Coast remains disorganized this morning, as a weak surface low (Invest 93L) remains along/near the coast of the FL Panhandle. Regardless of potential tropical development (reference latest NHC forecast), modest enhancement to the low-level wind field should occur as this feature tracks towards coastal/southeast LA by early Thursday morning. Thunderstorms should occasionally spread inland along/near the central Gulf Coast through the period, but overall severe potential still appears too limited to introduce a Marginal Risk with this update. ..Gleason/Bentley.. 07/16/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0730 AM CDT Wed Jul 16 2025 Valid 161300Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MIDWEST/GREAT LAKES AND CENTRAL HIGH PLAINS... ...SUMMARY... Scattered strong to severe thunderstorms are possible this afternoon and evening from parts of the central High Plains to the Great Lakes and Mid-Atlantic. ...Midwest/Great Lakes... A well-defined MCV is evident on radar/satellite imagery this morning over IA. This feature will drift east-northeastward today across the Midwest and Great Lakes, eventually reaching southern Ontario tonight. A related surface low will develop from IA to southern WI and Lake Michigan this afternoon/evening, with the primary synoptic front farther north in WI. Diurnal heating of a rather moist low-level airmass will likely yield around 1000-2500 J/kg of MLCAPE across southern WI into northern/central IL (locally stronger with southward extent). The modestly enhanced low/mid-level winds associated with the MCV should support around 30-40 kt of deep-layer shear, sufficient for organized severe thunderstorms. Current expectations are for a band of semi-discrete thunderstorms to develop across eastern IA into northern IL and southern/central WI by early to mid afternoon as large-scale ascent attendant to the MCV overspreads the destabilizing warm sector. Some of this activity could be supercellular initially and pose a threat for isolated severe hail along with damaging winds. With time late this afternoon and evening, gradual upscale growth into a bowing cluster should occur, with a greater risk for severe/damaging winds towards Lake Michigan and parts of southern Lower MI. Although low-level flow and related shear is not forecast to become overly strong this afternoon, it should be sufficient for some low-level updraft rotation and perhaps a few tornadoes, particularly across parts of southern WI/northern IL where semi-discrete convection may occur. ...Ohio Valley/Mid-Atlantic... A weak mid-level shortwave trough located over the OH Valley this morning will advance northeastward today to the northern Mid-Atlantic/NY. Recent visible satellite imagery this morning shows considerable cloud cover present with this feature, along with some low clouds downstream. Even so, filtered daytime heating of a seasonably moist airmass should support the development of weak to locally moderate instability by this afternoon. Poor lapse rates aloft may tend to inhibit stronger updrafts to some extent, but marginal deep-layer shear (generally around 20-30 kt) should still support some degree of convective organization. Loosely organized clusters and occasional cells may pose an isolated threat for damaging winds as they spread generally east-northeastward across parts of the OH Valley and Mid-Atlantic this afternoon/evening. Confidence in a more concentrated corridor of damaging winds remains too low to include greater severe probabilities at this time. ...Central Plains to Northern Missouri... A convectively reinforced surface front should stall by this afternoon across KS into eastern CO, with a modest low-level upslope flow regime occurring across the Front Range/central High Plains. On the southern periphery of an upper trough moving eastward over the northern/central Plains, thunderstorms should develop by early afternoon over the higher terrain of the central Rockies. This convection is forecast to move eastward into the adjacent High Plains through the rest of the afternoon, and continuing through the evening. The post-frontal airmass should only modestly destabilize, but enough instability and the presence of steepened lapse rates aloft are forecast to support robust updrafts. Weak low-level flow veering to westerly and gradually strengthening with height at mid/upper levels will likely foster around 35-45 kt of deep-layer shear. This will easily support supercells and associated large hail threat with the initial development. Some potential for upscale growth into a loosely organized cluster is possible across southeast CO and vicinity this evening along/near the stalled surface front. If this occurs, then severe winds would become the primary risk. Farther east across KS into northern MO, isolated convection may develop through peak afternoon heating along the front. While deep-layer shear is forecast to remain fairly modest, strong instability and steep mid-level lapse rates could still support occasional severe hail/wind with the more robust cores that can be sustained. Additional convection may develop along/north of the front this evening in a low-level warm advection regime, while also posing an isolated severe threat. ...Central Gulf Coast... Convection offshore from the central Gulf Coast remains disorganized this morning, as a weak surface low (Invest 93L) remains along/near the coast of the FL Panhandle. Regardless of potential tropical development (reference latest NHC forecast), modest enhancement to the low-level wind field should occur as this feature tracks towards coastal/southeast LA by early Thursday morning. Thunderstorms should occasionally spread inland along/near the central Gulf Coast through the period, but overall severe potential still appears too limited to introduce a Marginal Risk with this update. ..Gleason/Bentley.. 07/16/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0730 AM CDT Wed Jul 16 2025 Valid 161300Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MIDWEST/GREAT LAKES AND CENTRAL HIGH PLAINS... ...SUMMARY... Scattered strong to severe thunderstorms are possible this afternoon and evening from parts of the central High Plains to the Great Lakes and Mid-Atlantic. ...Midwest/Great Lakes... A well-defined MCV is evident on radar/satellite imagery this morning over IA. This feature will drift east-northeastward today across the Midwest and Great Lakes, eventually reaching southern Ontario tonight. A related surface low will develop from IA to southern WI and Lake Michigan this afternoon/evening, with the primary synoptic front farther north in WI. Diurnal heating of a rather moist low-level airmass will likely yield around 1000-2500 J/kg of MLCAPE across southern WI into northern/central IL (locally stronger with southward extent). The modestly enhanced low/mid-level winds associated with the MCV should support around 30-40 kt of deep-layer shear, sufficient for organized severe thunderstorms. Current expectations are for a band of semi-discrete thunderstorms to develop across eastern IA into northern IL and southern/central WI by early to mid afternoon as large-scale ascent attendant to the MCV overspreads the destabilizing warm sector. Some of this activity could be supercellular initially and pose a threat for isolated severe hail along with damaging winds. With time late this afternoon and evening, gradual upscale growth into a bowing cluster should occur, with a greater risk for severe/damaging winds towards Lake Michigan and parts of southern Lower MI. Although low-level flow and related shear is not forecast to become overly strong this afternoon, it should be sufficient for some low-level updraft rotation and perhaps a few tornadoes, particularly across parts of southern WI/northern IL where semi-discrete convection may occur. ...Ohio Valley/Mid-Atlantic... A weak mid-level shortwave trough located over the OH Valley this morning will advance northeastward today to the northern Mid-Atlantic/NY. Recent visible satellite imagery this morning shows considerable cloud cover present with this feature, along with some low clouds downstream. Even so, filtered daytime heating of a seasonably moist airmass should support the development of weak to locally moderate instability by this afternoon. Poor lapse rates aloft may tend to inhibit stronger updrafts to some extent, but marginal deep-layer shear (generally around 20-30 kt) should still support some degree of convective organization. Loosely organized clusters and occasional cells may pose an isolated threat for damaging winds as they spread generally east-northeastward across parts of the OH Valley and Mid-Atlantic this afternoon/evening. Confidence in a more concentrated corridor of damaging winds remains too low to include greater severe probabilities at this time. ...Central Plains to Northern Missouri... A convectively reinforced surface front should stall by this afternoon across KS into eastern CO, with a modest low-level upslope flow regime occurring across the Front Range/central High Plains. On the southern periphery of an upper trough moving eastward over the northern/central Plains, thunderstorms should develop by early afternoon over the higher terrain of the central Rockies. This convection is forecast to move eastward into the adjacent High Plains through the rest of the afternoon, and continuing through the evening. The post-frontal airmass should only modestly destabilize, but enough instability and the presence of steepened lapse rates aloft are forecast to support robust updrafts. Weak low-level flow veering to westerly and gradually strengthening with height at mid/upper levels will likely foster around 35-45 kt of deep-layer shear. This will easily support supercells and associated large hail threat with the initial development. Some potential for upscale growth into a loosely organized cluster is possible across southeast CO and vicinity this evening along/near the stalled surface front. If this occurs, then severe winds would become the primary risk. Farther east across KS into northern MO, isolated convection may develop through peak afternoon heating along the front. While deep-layer shear is forecast to remain fairly modest, strong instability and steep mid-level lapse rates could still support occasional severe hail/wind with the more robust cores that can be sustained. Additional convection may develop along/north of the front this evening in a low-level warm advection regime, while also posing an isolated severe threat. ...Central Gulf Coast... Convection offshore from the central Gulf Coast remains disorganized this morning, as a weak surface low (Invest 93L) remains along/near the coast of the FL Panhandle. Regardless of potential tropical development (reference latest NHC forecast), modest enhancement to the low-level wind field should occur as this feature tracks towards coastal/southeast LA by early Thursday morning. Thunderstorms should occasionally spread inland along/near the central Gulf Coast through the period, but overall severe potential still appears too limited to introduce a Marginal Risk with this update. ..Gleason/Bentley.. 07/16/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0730 AM CDT Wed Jul 16 2025 Valid 161300Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MIDWEST/GREAT LAKES AND CENTRAL HIGH PLAINS... ...SUMMARY... Scattered strong to severe thunderstorms are possible this afternoon and evening from parts of the central High Plains to the Great Lakes and Mid-Atlantic. ...Midwest/Great Lakes... A well-defined MCV is evident on radar/satellite imagery this morning over IA. This feature will drift east-northeastward today across the Midwest and Great Lakes, eventually reaching southern Ontario tonight. A related surface low will develop from IA to southern WI and Lake Michigan this afternoon/evening, with the primary synoptic front farther north in WI. Diurnal heating of a rather moist low-level airmass will likely yield around 1000-2500 J/kg of MLCAPE across southern WI into northern/central IL (locally stronger with southward extent). The modestly enhanced low/mid-level winds associated with the MCV should support around 30-40 kt of deep-layer shear, sufficient for organized severe thunderstorms. Current expectations are for a band of semi-discrete thunderstorms to develop across eastern IA into northern IL and southern/central WI by early to mid afternoon as large-scale ascent attendant to the MCV overspreads the destabilizing warm sector. Some of this activity could be supercellular initially and pose a threat for isolated severe hail along with damaging winds. With time late this afternoon and evening, gradual upscale growth into a bowing cluster should occur, with a greater risk for severe/damaging winds towards Lake Michigan and parts of southern Lower MI. Although low-level flow and related shear is not forecast to become overly strong this afternoon, it should be sufficient for some low-level updraft rotation and perhaps a few tornadoes, particularly across parts of southern WI/northern IL where semi-discrete convection may occur. ...Ohio Valley/Mid-Atlantic... A weak mid-level shortwave trough located over the OH Valley this morning will advance northeastward today to the northern Mid-Atlantic/NY. Recent visible satellite imagery this morning shows considerable cloud cover present with this feature, along with some low clouds downstream. Even so, filtered daytime heating of a seasonably moist airmass should support the development of weak to locally moderate instability by this afternoon. Poor lapse rates aloft may tend to inhibit stronger updrafts to some extent, but marginal deep-layer shear (generally around 20-30 kt) should still support some degree of convective organization. Loosely organized clusters and occasional cells may pose an isolated threat for damaging winds as they spread generally east-northeastward across parts of the OH Valley and Mid-Atlantic this afternoon/evening. Confidence in a more concentrated corridor of damaging winds remains too low to include greater severe probabilities at this time. ...Central Plains to Northern Missouri... A convectively reinforced surface front should stall by this afternoon across KS into eastern CO, with a modest low-level upslope flow regime occurring across the Front Range/central High Plains. On the southern periphery of an upper trough moving eastward over the northern/central Plains, thunderstorms should develop by early afternoon over the higher terrain of the central Rockies. This convection is forecast to move eastward into the adjacent High Plains through the rest of the afternoon, and continuing through the evening. The post-frontal airmass should only modestly destabilize, but enough instability and the presence of steepened lapse rates aloft are forecast to support robust updrafts. Weak low-level flow veering to westerly and gradually strengthening with height at mid/upper levels will likely foster around 35-45 kt of deep-layer shear. This will easily support supercells and associated large hail threat with the initial development. Some potential for upscale growth into a loosely organized cluster is possible across southeast CO and vicinity this evening along/near the stalled surface front. If this occurs, then severe winds would become the primary risk. Farther east across KS into northern MO, isolated convection may develop through peak afternoon heating along the front. While deep-layer shear is forecast to remain fairly modest, strong instability and steep mid-level lapse rates could still support occasional severe hail/wind with the more robust cores that can be sustained. Additional convection may develop along/north of the front this evening in a low-level warm advection regime, while also posing an isolated severe threat. ...Central Gulf Coast... Convection offshore from the central Gulf Coast remains disorganized this morning, as a weak surface low (Invest 93L) remains along/near the coast of the FL Panhandle. Regardless of potential tropical development (reference latest NHC forecast), modest enhancement to the low-level wind field should occur as this feature tracks towards coastal/southeast LA by early Thursday morning. Thunderstorms should occasionally spread inland along/near the central Gulf Coast through the period, but overall severe potential still appears too limited to introduce a Marginal Risk with this update. ..Gleason/Bentley.. 07/16/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0730 AM CDT Wed Jul 16 2025 Valid 161300Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MIDWEST/GREAT LAKES AND CENTRAL HIGH PLAINS... ...SUMMARY... Scattered strong to severe thunderstorms are possible this afternoon and evening from parts of the central High Plains to the Great Lakes and Mid-Atlantic. ...Midwest/Great Lakes... A well-defined MCV is evident on radar/satellite imagery this morning over IA. This feature will drift east-northeastward today across the Midwest and Great Lakes, eventually reaching southern Ontario tonight. A related surface low will develop from IA to southern WI and Lake Michigan this afternoon/evening, with the primary synoptic front farther north in WI. Diurnal heating of a rather moist low-level airmass will likely yield around 1000-2500 J/kg of MLCAPE across southern WI into northern/central IL (locally stronger with southward extent). The modestly enhanced low/mid-level winds associated with the MCV should support around 30-40 kt of deep-layer shear, sufficient for organized severe thunderstorms. Current expectations are for a band of semi-discrete thunderstorms to develop across eastern IA into northern IL and southern/central WI by early to mid afternoon as large-scale ascent attendant to the MCV overspreads the destabilizing warm sector. Some of this activity could be supercellular initially and pose a threat for isolated severe hail along with damaging winds. With time late this afternoon and evening, gradual upscale growth into a bowing cluster should occur, with a greater risk for severe/damaging winds towards Lake Michigan and parts of southern Lower MI. Although low-level flow and related shear is not forecast to become overly strong this afternoon, it should be sufficient for some low-level updraft rotation and perhaps a few tornadoes, particularly across parts of southern WI/northern IL where semi-discrete convection may occur. ...Ohio Valley/Mid-Atlantic... A weak mid-level shortwave trough located over the OH Valley this morning will advance northeastward today to the northern Mid-Atlantic/NY. Recent visible satellite imagery this morning shows considerable cloud cover present with this feature, along with some low clouds downstream. Even so, filtered daytime heating of a seasonably moist airmass should support the development of weak to locally moderate instability by this afternoon. Poor lapse rates aloft may tend to inhibit stronger updrafts to some extent, but marginal deep-layer shear (generally around 20-30 kt) should still support some degree of convective organization. Loosely organized clusters and occasional cells may pose an isolated threat for damaging winds as they spread generally east-northeastward across parts of the OH Valley and Mid-Atlantic this afternoon/evening. Confidence in a more concentrated corridor of damaging winds remains too low to include greater severe probabilities at this time. ...Central Plains to Northern Missouri... A convectively reinforced surface front should stall by this afternoon across KS into eastern CO, with a modest low-level upslope flow regime occurring across the Front Range/central High Plains. On the southern periphery of an upper trough moving eastward over the northern/central Plains, thunderstorms should develop by early afternoon over the higher terrain of the central Rockies. This convection is forecast to move eastward into the adjacent High Plains through the rest of the afternoon, and continuing through the evening. The post-frontal airmass should only modestly destabilize, but enough instability and the presence of steepened lapse rates aloft are forecast to support robust updrafts. Weak low-level flow veering to westerly and gradually strengthening with height at mid/upper levels will likely foster around 35-45 kt of deep-layer shear. This will easily support supercells and associated large hail threat with the initial development. Some potential for upscale growth into a loosely organized cluster is possible across southeast CO and vicinity this evening along/near the stalled surface front. If this occurs, then severe winds would become the primary risk. Farther east across KS into northern MO, isolated convection may develop through peak afternoon heating along the front. While deep-layer shear is forecast to remain fairly modest, strong instability and steep mid-level lapse rates could still support occasional severe hail/wind with the more robust cores that can be sustained. Additional convection may develop along/north of the front this evening in a low-level warm advection regime, while also posing an isolated severe threat. ...Central Gulf Coast... Convection offshore from the central Gulf Coast remains disorganized this morning, as a weak surface low (Invest 93L) remains along/near the coast of the FL Panhandle. Regardless of potential tropical development (reference latest NHC forecast), modest enhancement to the low-level wind field should occur as this feature tracks towards coastal/southeast LA by early Thursday morning. Thunderstorms should occasionally spread inland along/near the central Gulf Coast through the period, but overall severe potential still appears too limited to introduce a Marginal Risk with this update. ..Gleason/Bentley.. 07/16/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0730 AM CDT Wed Jul 16 2025 Valid 161300Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MIDWEST/GREAT LAKES AND CENTRAL HIGH PLAINS... ...SUMMARY... Scattered strong to severe thunderstorms are possible this afternoon and evening from parts of the central High Plains to the Great Lakes and Mid-Atlantic. ...Midwest/Great Lakes... A well-defined MCV is evident on radar/satellite imagery this morning over IA. This feature will drift east-northeastward today across the Midwest and Great Lakes, eventually reaching southern Ontario tonight. A related surface low will develop from IA to southern WI and Lake Michigan this afternoon/evening, with the primary synoptic front farther north in WI. Diurnal heating of a rather moist low-level airmass will likely yield around 1000-2500 J/kg of MLCAPE across southern WI into northern/central IL (locally stronger with southward extent). The modestly enhanced low/mid-level winds associated with the MCV should support around 30-40 kt of deep-layer shear, sufficient for organized severe thunderstorms. Current expectations are for a band of semi-discrete thunderstorms to develop across eastern IA into northern IL and southern/central WI by early to mid afternoon as large-scale ascent attendant to the MCV overspreads the destabilizing warm sector. Some of this activity could be supercellular initially and pose a threat for isolated severe hail along with damaging winds. With time late this afternoon and evening, gradual upscale growth into a bowing cluster should occur, with a greater risk for severe/damaging winds towards Lake Michigan and parts of southern Lower MI. Although low-level flow and related shear is not forecast to become overly strong this afternoon, it should be sufficient for some low-level updraft rotation and perhaps a few tornadoes, particularly across parts of southern WI/northern IL where semi-discrete convection may occur. ...Ohio Valley/Mid-Atlantic... A weak mid-level shortwave trough located over the OH Valley this morning will advance northeastward today to the northern Mid-Atlantic/NY. Recent visible satellite imagery this morning shows considerable cloud cover present with this feature, along with some low clouds downstream. Even so, filtered daytime heating of a seasonably moist airmass should support the development of weak to locally moderate instability by this afternoon. Poor lapse rates aloft may tend to inhibit stronger updrafts to some extent, but marginal deep-layer shear (generally around 20-30 kt) should still support some degree of convective organization. Loosely organized clusters and occasional cells may pose an isolated threat for damaging winds as they spread generally east-northeastward across parts of the OH Valley and Mid-Atlantic this afternoon/evening. Confidence in a more concentrated corridor of damaging winds remains too low to include greater severe probabilities at this time. ...Central Plains to Northern Missouri... A convectively reinforced surface front should stall by this afternoon across KS into eastern CO, with a modest low-level upslope flow regime occurring across the Front Range/central High Plains. On the southern periphery of an upper trough moving eastward over the northern/central Plains, thunderstorms should develop by early afternoon over the higher terrain of the central Rockies. This convection is forecast to move eastward into the adjacent High Plains through the rest of the afternoon, and continuing through the evening. The post-frontal airmass should only modestly destabilize, but enough instability and the presence of steepened lapse rates aloft are forecast to support robust updrafts. Weak low-level flow veering to westerly and gradually strengthening with height at mid/upper levels will likely foster around 35-45 kt of deep-layer shear. This will easily support supercells and associated large hail threat with the initial development. Some potential for upscale growth into a loosely organized cluster is possible across southeast CO and vicinity this evening along/near the stalled surface front. If this occurs, then severe winds would become the primary risk. Farther east across KS into northern MO, isolated convection may develop through peak afternoon heating along the front. While deep-layer shear is forecast to remain fairly modest, strong instability and steep mid-level lapse rates could still support occasional severe hail/wind with the more robust cores that can be sustained. Additional convection may develop along/north of the front this evening in a low-level warm advection regime, while also posing an isolated severe threat. ...Central Gulf Coast... Convection offshore from the central Gulf Coast remains disorganized this morning, as a weak surface low (Invest 93L) remains along/near the coast of the FL Panhandle. Regardless of potential tropical development (reference latest NHC forecast), modest enhancement to the low-level wind field should occur as this feature tracks towards coastal/southeast LA by early Thursday morning. Thunderstorms should occasionally spread inland along/near the central Gulf Coast through the period, but overall severe potential still appears too limited to introduce a Marginal Risk with this update. ..Gleason/Bentley.. 07/16/2025 Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0245 AM CDT Wed Jul 16 2025 Valid 191200Z - 241200Z ...DISCUSSION... A low-amplitude upper trough will move from the Great Lakes through the Northeast during the Day 4-5/Sat-Sun period. Some enhanced westerly flow aloft and a deepening surface low will accompany this system. While forecast guidance varies with timing and location of these features, some severe potential could develop from portions of the Great Lakes to the Northeast/Mid-Atlantic over the weekend ahead of a cold front. Details are still uncertain regarding where a better chance for severe storms may develop, precluding probabilities. By early next week, upper ridging is forecast for much of the CONUS east of the Rockies while an upper shortwave trough persists over the Northwest. Late in the period, a shortwave impulse may eject from the Northwest upper shortwave and move across the northern Plains, posing some increasing risk for severe potential, though confidence in this scenario remains too low to include an outlook area at this time. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0245 AM CDT Wed Jul 16 2025 Valid 191200Z - 241200Z ...DISCUSSION... A low-amplitude upper trough will move from the Great Lakes through the Northeast during the Day 4-5/Sat-Sun period. Some enhanced westerly flow aloft and a deepening surface low will accompany this system. While forecast guidance varies with timing and location of these features, some severe potential could develop from portions of the Great Lakes to the Northeast/Mid-Atlantic over the weekend ahead of a cold front. Details are still uncertain regarding where a better chance for severe storms may develop, precluding probabilities. By early next week, upper ridging is forecast for much of the CONUS east of the Rockies while an upper shortwave trough persists over the Northwest. Late in the period, a shortwave impulse may eject from the Northwest upper shortwave and move across the northern Plains, posing some increasing risk for severe potential, though confidence in this scenario remains too low to include an outlook area at this time. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0245 AM CDT Wed Jul 16 2025 Valid 191200Z - 241200Z ...DISCUSSION... A low-amplitude upper trough will move from the Great Lakes through the Northeast during the Day 4-5/Sat-Sun period. Some enhanced westerly flow aloft and a deepening surface low will accompany this system. While forecast guidance varies with timing and location of these features, some severe potential could develop from portions of the Great Lakes to the Northeast/Mid-Atlantic over the weekend ahead of a cold front. Details are still uncertain regarding where a better chance for severe storms may develop, precluding probabilities. By early next week, upper ridging is forecast for much of the CONUS east of the Rockies while an upper shortwave trough persists over the Northwest. Late in the period, a shortwave impulse may eject from the Northwest upper shortwave and move across the northern Plains, posing some increasing risk for severe potential, though confidence in this scenario remains too low to include an outlook area at this time. Read more