Aggregator

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0256 PM CDT Fri Apr 05 2024 Valid 061200Z - 071200Z ...CRITICAL FIRE WEATHER AREA FOR THE SOUTHERN HIGH PLAINS... No changes are needed to the D2 Fire Weather Outlook. Though no Extremely Critical areas were added with this outlook, hi-res guidance from the HREF continues to show around 10-30% probability of Extremely Critical conditions across the northern Texas Panhandle/Oklahoma Panhandle into far southeastern Colorado. Deterministic models continue to show significant spread in wind speeds and minimum relative humidity but it seems likely that localized Extremely Critical conditions will be possible, mainly across the northern Texas Panhandle/Oklahoma Panhandle. Should confidence increase in more widespread conditions, an Extremely Critical may be needed with the upcoming transition to D1. ..Thornton.. 04/05/2024 .PREV DISCUSSION... /ISSUED 0203 AM CDT Fri Apr 05 2024/ ...Synopsis... The second of a two-day fire weather event is anticipated on Saturday across southern NM/far west TX to southeast CO and southwest KS. Robust lee cyclogenesis is anticipated across the central High Plains by 18 UTC Saturday as a progressive upper-level wave (currently moving onto the CA coast) overspreads the region. The surface low is forecast to shift east into the Plains through the afternoon with a trailing surface trough/Pacific front pushing east across the southern High Plains by late morning. As this occurs, west/northwesterly post-frontal winds will advect a dry air mass off the central/southern Rockies into the High Plains. Downslope warming/drying of this air mass will promote widespread RH reductions into the 10-20% range across NM, western TX, and portions of OK/CO/KS. Latest high-res ensemble guidance shows reasonably high confidence in sub-15% RH within the critical risk area, and the typically drier/windier solutions hint that single-digit RH minimums are possible. Winds are expected to increase to 20-25 mph (gusting to 40-50 mph) by early afternoon amid a strengthening surface pressure gradient and deepening boundary-layer mixing. Sustained winds between 30-35 mph winds possible under the mid-level jet maximum, which should be located broadly across the northern TX and OK Panhandles. This region will see the highest potential for extremely critical fire weather conditions. Consideration was given to introducing an Extremely Critical risk area, but somewhat low ensemble consensus for sustained 30+ mph winds (only 10-30% probability) precluded higher risk headlines. These low probabilities may be associated with spread regarding the placement and magnitude of the surface low (up to a 4 mb difference between some solutions). These details should become better resolved heading into the Day-1 time frame. Regardless, fuels across the region should be very receptive after warm, dry, and windy conditions on Friday, which should support the high-end Critical fire weather risk on Saturday. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0256 PM CDT Fri Apr 05 2024 Valid 061200Z - 071200Z ...CRITICAL FIRE WEATHER AREA FOR THE SOUTHERN HIGH PLAINS... No changes are needed to the D2 Fire Weather Outlook. Though no Extremely Critical areas were added with this outlook, hi-res guidance from the HREF continues to show around 10-30% probability of Extremely Critical conditions across the northern Texas Panhandle/Oklahoma Panhandle into far southeastern Colorado. Deterministic models continue to show significant spread in wind speeds and minimum relative humidity but it seems likely that localized Extremely Critical conditions will be possible, mainly across the northern Texas Panhandle/Oklahoma Panhandle. Should confidence increase in more widespread conditions, an Extremely Critical may be needed with the upcoming transition to D1. ..Thornton.. 04/05/2024 .PREV DISCUSSION... /ISSUED 0203 AM CDT Fri Apr 05 2024/ ...Synopsis... The second of a two-day fire weather event is anticipated on Saturday across southern NM/far west TX to southeast CO and southwest KS. Robust lee cyclogenesis is anticipated across the central High Plains by 18 UTC Saturday as a progressive upper-level wave (currently moving onto the CA coast) overspreads the region. The surface low is forecast to shift east into the Plains through the afternoon with a trailing surface trough/Pacific front pushing east across the southern High Plains by late morning. As this occurs, west/northwesterly post-frontal winds will advect a dry air mass off the central/southern Rockies into the High Plains. Downslope warming/drying of this air mass will promote widespread RH reductions into the 10-20% range across NM, western TX, and portions of OK/CO/KS. Latest high-res ensemble guidance shows reasonably high confidence in sub-15% RH within the critical risk area, and the typically drier/windier solutions hint that single-digit RH minimums are possible. Winds are expected to increase to 20-25 mph (gusting to 40-50 mph) by early afternoon amid a strengthening surface pressure gradient and deepening boundary-layer mixing. Sustained winds between 30-35 mph winds possible under the mid-level jet maximum, which should be located broadly across the northern TX and OK Panhandles. This region will see the highest potential for extremely critical fire weather conditions. Consideration was given to introducing an Extremely Critical risk area, but somewhat low ensemble consensus for sustained 30+ mph winds (only 10-30% probability) precluded higher risk headlines. These low probabilities may be associated with spread regarding the placement and magnitude of the surface low (up to a 4 mb difference between some solutions). These details should become better resolved heading into the Day-1 time frame. Regardless, fuels across the region should be very receptive after warm, dry, and windy conditions on Friday, which should support the high-end Critical fire weather risk on Saturday. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0256 PM CDT Fri Apr 05 2024 Valid 061200Z - 071200Z ...CRITICAL FIRE WEATHER AREA FOR THE SOUTHERN HIGH PLAINS... No changes are needed to the D2 Fire Weather Outlook. Though no Extremely Critical areas were added with this outlook, hi-res guidance from the HREF continues to show around 10-30% probability of Extremely Critical conditions across the northern Texas Panhandle/Oklahoma Panhandle into far southeastern Colorado. Deterministic models continue to show significant spread in wind speeds and minimum relative humidity but it seems likely that localized Extremely Critical conditions will be possible, mainly across the northern Texas Panhandle/Oklahoma Panhandle. Should confidence increase in more widespread conditions, an Extremely Critical may be needed with the upcoming transition to D1. ..Thornton.. 04/05/2024 .PREV DISCUSSION... /ISSUED 0203 AM CDT Fri Apr 05 2024/ ...Synopsis... The second of a two-day fire weather event is anticipated on Saturday across southern NM/far west TX to southeast CO and southwest KS. Robust lee cyclogenesis is anticipated across the central High Plains by 18 UTC Saturday as a progressive upper-level wave (currently moving onto the CA coast) overspreads the region. The surface low is forecast to shift east into the Plains through the afternoon with a trailing surface trough/Pacific front pushing east across the southern High Plains by late morning. As this occurs, west/northwesterly post-frontal winds will advect a dry air mass off the central/southern Rockies into the High Plains. Downslope warming/drying of this air mass will promote widespread RH reductions into the 10-20% range across NM, western TX, and portions of OK/CO/KS. Latest high-res ensemble guidance shows reasonably high confidence in sub-15% RH within the critical risk area, and the typically drier/windier solutions hint that single-digit RH minimums are possible. Winds are expected to increase to 20-25 mph (gusting to 40-50 mph) by early afternoon amid a strengthening surface pressure gradient and deepening boundary-layer mixing. Sustained winds between 30-35 mph winds possible under the mid-level jet maximum, which should be located broadly across the northern TX and OK Panhandles. This region will see the highest potential for extremely critical fire weather conditions. Consideration was given to introducing an Extremely Critical risk area, but somewhat low ensemble consensus for sustained 30+ mph winds (only 10-30% probability) precluded higher risk headlines. These low probabilities may be associated with spread regarding the placement and magnitude of the surface low (up to a 4 mb difference between some solutions). These details should become better resolved heading into the Day-1 time frame. Regardless, fuels across the region should be very receptive after warm, dry, and windy conditions on Friday, which should support the high-end Critical fire weather risk on Saturday. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0256 PM CDT Fri Apr 05 2024 Valid 061200Z - 071200Z ...CRITICAL FIRE WEATHER AREA FOR THE SOUTHERN HIGH PLAINS... No changes are needed to the D2 Fire Weather Outlook. Though no Extremely Critical areas were added with this outlook, hi-res guidance from the HREF continues to show around 10-30% probability of Extremely Critical conditions across the northern Texas Panhandle/Oklahoma Panhandle into far southeastern Colorado. Deterministic models continue to show significant spread in wind speeds and minimum relative humidity but it seems likely that localized Extremely Critical conditions will be possible, mainly across the northern Texas Panhandle/Oklahoma Panhandle. Should confidence increase in more widespread conditions, an Extremely Critical may be needed with the upcoming transition to D1. ..Thornton.. 04/05/2024 .PREV DISCUSSION... /ISSUED 0203 AM CDT Fri Apr 05 2024/ ...Synopsis... The second of a two-day fire weather event is anticipated on Saturday across southern NM/far west TX to southeast CO and southwest KS. Robust lee cyclogenesis is anticipated across the central High Plains by 18 UTC Saturday as a progressive upper-level wave (currently moving onto the CA coast) overspreads the region. The surface low is forecast to shift east into the Plains through the afternoon with a trailing surface trough/Pacific front pushing east across the southern High Plains by late morning. As this occurs, west/northwesterly post-frontal winds will advect a dry air mass off the central/southern Rockies into the High Plains. Downslope warming/drying of this air mass will promote widespread RH reductions into the 10-20% range across NM, western TX, and portions of OK/CO/KS. Latest high-res ensemble guidance shows reasonably high confidence in sub-15% RH within the critical risk area, and the typically drier/windier solutions hint that single-digit RH minimums are possible. Winds are expected to increase to 20-25 mph (gusting to 40-50 mph) by early afternoon amid a strengthening surface pressure gradient and deepening boundary-layer mixing. Sustained winds between 30-35 mph winds possible under the mid-level jet maximum, which should be located broadly across the northern TX and OK Panhandles. This region will see the highest potential for extremely critical fire weather conditions. Consideration was given to introducing an Extremely Critical risk area, but somewhat low ensemble consensus for sustained 30+ mph winds (only 10-30% probability) precluded higher risk headlines. These low probabilities may be associated with spread regarding the placement and magnitude of the surface low (up to a 4 mb difference between some solutions). These details should become better resolved heading into the Day-1 time frame. Regardless, fuels across the region should be very receptive after warm, dry, and windy conditions on Friday, which should support the high-end Critical fire weather risk on Saturday. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0242 PM CDT Fri Apr 05 2024 Valid 052000Z - 061200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not expected today or tonight. ...Discussion... No changes appear necessary to the ongoing outlook at this time. ..Goss.. 04/05/2024 .PREV DISCUSSION... /ISSUED 1129 AM CDT Fri Apr 05 2024/ ...Northern Rockies... Associated with the exit region of the polar jet related to the Western U.S. upper trough, forcing for ascent and modest moisture/buoyancy will lead to at least widely scattered thunderstorms by mid/late afternoon. These storms should generally focus across eastern Idaho and far western Montana this afternoon, and then additional parts of western/southern Montana and Wyoming into this evening. Steep lapse rates and sufficient buoyancy could allow for some stronger storms capable of gusty winds/hail, but organized/sustained severe thunderstorms are not currently expected. ...Coastal Southern California... Isolated low-topped thunderstorms will remain a possibility within the post-frontal environment beneath the mid/upper-level trough, where mid-level temperatures (500 mb) are generally between -25C to -30C. While a couple of east/southeastward-moving stronger storms could materialize through the afternoon near far southern California coastal areas, severe thunderstorms are unlikely given the limited boundary layer moisture and buoyancy (generally a couple hundred J/kg MUCAPE at most). Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0242 PM CDT Fri Apr 05 2024 Valid 052000Z - 061200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not expected today or tonight. ...Discussion... No changes appear necessary to the ongoing outlook at this time. ..Goss.. 04/05/2024 .PREV DISCUSSION... /ISSUED 1129 AM CDT Fri Apr 05 2024/ ...Northern Rockies... Associated with the exit region of the polar jet related to the Western U.S. upper trough, forcing for ascent and modest moisture/buoyancy will lead to at least widely scattered thunderstorms by mid/late afternoon. These storms should generally focus across eastern Idaho and far western Montana this afternoon, and then additional parts of western/southern Montana and Wyoming into this evening. Steep lapse rates and sufficient buoyancy could allow for some stronger storms capable of gusty winds/hail, but organized/sustained severe thunderstorms are not currently expected. ...Coastal Southern California... Isolated low-topped thunderstorms will remain a possibility within the post-frontal environment beneath the mid/upper-level trough, where mid-level temperatures (500 mb) are generally between -25C to -30C. While a couple of east/southeastward-moving stronger storms could materialize through the afternoon near far southern California coastal areas, severe thunderstorms are unlikely given the limited boundary layer moisture and buoyancy (generally a couple hundred J/kg MUCAPE at most). Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0242 PM CDT Fri Apr 05 2024 Valid 052000Z - 061200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not expected today or tonight. ...Discussion... No changes appear necessary to the ongoing outlook at this time. ..Goss.. 04/05/2024 .PREV DISCUSSION... /ISSUED 1129 AM CDT Fri Apr 05 2024/ ...Northern Rockies... Associated with the exit region of the polar jet related to the Western U.S. upper trough, forcing for ascent and modest moisture/buoyancy will lead to at least widely scattered thunderstorms by mid/late afternoon. These storms should generally focus across eastern Idaho and far western Montana this afternoon, and then additional parts of western/southern Montana and Wyoming into this evening. Steep lapse rates and sufficient buoyancy could allow for some stronger storms capable of gusty winds/hail, but organized/sustained severe thunderstorms are not currently expected. ...Coastal Southern California... Isolated low-topped thunderstorms will remain a possibility within the post-frontal environment beneath the mid/upper-level trough, where mid-level temperatures (500 mb) are generally between -25C to -30C. While a couple of east/southeastward-moving stronger storms could materialize through the afternoon near far southern California coastal areas, severe thunderstorms are unlikely given the limited boundary layer moisture and buoyancy (generally a couple hundred J/kg MUCAPE at most). Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0242 PM CDT Fri Apr 05 2024 Valid 052000Z - 061200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not expected today or tonight. ...Discussion... No changes appear necessary to the ongoing outlook at this time. ..Goss.. 04/05/2024 .PREV DISCUSSION... /ISSUED 1129 AM CDT Fri Apr 05 2024/ ...Northern Rockies... Associated with the exit region of the polar jet related to the Western U.S. upper trough, forcing for ascent and modest moisture/buoyancy will lead to at least widely scattered thunderstorms by mid/late afternoon. These storms should generally focus across eastern Idaho and far western Montana this afternoon, and then additional parts of western/southern Montana and Wyoming into this evening. Steep lapse rates and sufficient buoyancy could allow for some stronger storms capable of gusty winds/hail, but organized/sustained severe thunderstorms are not currently expected. ...Coastal Southern California... Isolated low-topped thunderstorms will remain a possibility within the post-frontal environment beneath the mid/upper-level trough, where mid-level temperatures (500 mb) are generally between -25C to -30C. While a couple of east/southeastward-moving stronger storms could materialize through the afternoon near far southern California coastal areas, severe thunderstorms are unlikely given the limited boundary layer moisture and buoyancy (generally a couple hundred J/kg MUCAPE at most). Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0242 PM CDT Fri Apr 05 2024 Valid 052000Z - 061200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not expected today or tonight. ...Discussion... No changes appear necessary to the ongoing outlook at this time. ..Goss.. 04/05/2024 .PREV DISCUSSION... /ISSUED 1129 AM CDT Fri Apr 05 2024/ ...Northern Rockies... Associated with the exit region of the polar jet related to the Western U.S. upper trough, forcing for ascent and modest moisture/buoyancy will lead to at least widely scattered thunderstorms by mid/late afternoon. These storms should generally focus across eastern Idaho and far western Montana this afternoon, and then additional parts of western/southern Montana and Wyoming into this evening. Steep lapse rates and sufficient buoyancy could allow for some stronger storms capable of gusty winds/hail, but organized/sustained severe thunderstorms are not currently expected. ...Coastal Southern California... Isolated low-topped thunderstorms will remain a possibility within the post-frontal environment beneath the mid/upper-level trough, where mid-level temperatures (500 mb) are generally between -25C to -30C. While a couple of east/southeastward-moving stronger storms could materialize through the afternoon near far southern California coastal areas, severe thunderstorms are unlikely given the limited boundary layer moisture and buoyancy (generally a couple hundred J/kg MUCAPE at most). Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0242 PM CDT Fri Apr 05 2024 Valid 052000Z - 061200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not expected today or tonight. ...Discussion... No changes appear necessary to the ongoing outlook at this time. ..Goss.. 04/05/2024 .PREV DISCUSSION... /ISSUED 1129 AM CDT Fri Apr 05 2024/ ...Northern Rockies... Associated with the exit region of the polar jet related to the Western U.S. upper trough, forcing for ascent and modest moisture/buoyancy will lead to at least widely scattered thunderstorms by mid/late afternoon. These storms should generally focus across eastern Idaho and far western Montana this afternoon, and then additional parts of western/southern Montana and Wyoming into this evening. Steep lapse rates and sufficient buoyancy could allow for some stronger storms capable of gusty winds/hail, but organized/sustained severe thunderstorms are not currently expected. ...Coastal Southern California... Isolated low-topped thunderstorms will remain a possibility within the post-frontal environment beneath the mid/upper-level trough, where mid-level temperatures (500 mb) are generally between -25C to -30C. While a couple of east/southeastward-moving stronger storms could materialize through the afternoon near far southern California coastal areas, severe thunderstorms are unlikely given the limited boundary layer moisture and buoyancy (generally a couple hundred J/kg MUCAPE at most). Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0242 PM CDT Fri Apr 05 2024 Valid 052000Z - 061200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not expected today or tonight. ...Discussion... No changes appear necessary to the ongoing outlook at this time. ..Goss.. 04/05/2024 .PREV DISCUSSION... /ISSUED 1129 AM CDT Fri Apr 05 2024/ ...Northern Rockies... Associated with the exit region of the polar jet related to the Western U.S. upper trough, forcing for ascent and modest moisture/buoyancy will lead to at least widely scattered thunderstorms by mid/late afternoon. These storms should generally focus across eastern Idaho and far western Montana this afternoon, and then additional parts of western/southern Montana and Wyoming into this evening. Steep lapse rates and sufficient buoyancy could allow for some stronger storms capable of gusty winds/hail, but organized/sustained severe thunderstorms are not currently expected. ...Coastal Southern California... Isolated low-topped thunderstorms will remain a possibility within the post-frontal environment beneath the mid/upper-level trough, where mid-level temperatures (500 mb) are generally between -25C to -30C. While a couple of east/southeastward-moving stronger storms could materialize through the afternoon near far southern California coastal areas, severe thunderstorms are unlikely given the limited boundary layer moisture and buoyancy (generally a couple hundred J/kg MUCAPE at most). Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1227 PM CDT Fri Apr 05 2024 Valid 061200Z - 071200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM SOUTHWESTERN AND CENTRAL NEBRASKA INTO PORTIONS OF CENTRAL AND EASTERN KANSAS... ...SUMMARY... Strong/locally severe storms, capable of producing hail and strong wind gusts, will be possible across parts of the central and southern Plains Saturday afternoon and evening. A brief tornado or two may also occur. ...Synopsis... While an upper low will continue to linger just off the New England coast, the more substantial system with respect to potentially severe convection will be a second low, shifting across the western U.S. through the Day 1 time period and then into the central Plains Saturday and Saturday night. At the surface, a developing low will shift into the central Plains through the second half of the period, with a cold front to shift eastward into/across the central and southern Plains through the period. ...Western Nebraska across central and eastern Kansas, and into eastern Oklahoma... By Saturday morning/the start of the Day 2 period, the aforementioned western U.S. upper low will be in the process of deepening, as a strong (100-plus kt) mid-level jet streak shifts across Arizona/New Mexico into the southern High Plains early in the day. In response to the deepening low, surface cyclogenesis is expected into the afternoon across the Colorado/Kansas/Nebraska border region, with continued through the evening as the low shifts into western/central Nebraska. Despite a lack of moisture, daytime heating combined with steep lapse rates aloft will result in modest afternoon destabilization, with roughly 500 J/kg mixed-layer CAPE expected to develop just ahead of the evolving surface low, from southwestern Nebraska east-southeastward northern Kansas, and then southward into the southern Plains. By mid afternoon, low-topped storm development is expected, as strong ascent focused near the near the surface low, and the cold/occluded front extending east-southeastward across southern Nebraska. Storms should be initially cellular, but are likely to grow upscale into an arcing line, that may eventually extend southward into eastern Oklahoma and possibly northeastern Texas. With strongly backed low-level flow, veering with height, shear will be sufficient to support rotating updrafts -- particularly across the Nebraska portion of the risk area. Here, locally damaging wind gusts and hail in the inch to inch-and-a-half range may occur in roughly the 3PM to 7PM time frame, along with potential for a couple of brief tornadoes. Tornado threat should remain limited due to dewpoints expected to remain only in the low to mid 40s. With the loss of diurnal heating, an evening convective weakening trend is expected, with severe risk likely to have diminished to minimal levels by late evening. ..Goss.. 04/05/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1227 PM CDT Fri Apr 05 2024 Valid 061200Z - 071200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM SOUTHWESTERN AND CENTRAL NEBRASKA INTO PORTIONS OF CENTRAL AND EASTERN KANSAS... ...SUMMARY... Strong/locally severe storms, capable of producing hail and strong wind gusts, will be possible across parts of the central and southern Plains Saturday afternoon and evening. A brief tornado or two may also occur. ...Synopsis... While an upper low will continue to linger just off the New England coast, the more substantial system with respect to potentially severe convection will be a second low, shifting across the western U.S. through the Day 1 time period and then into the central Plains Saturday and Saturday night. At the surface, a developing low will shift into the central Plains through the second half of the period, with a cold front to shift eastward into/across the central and southern Plains through the period. ...Western Nebraska across central and eastern Kansas, and into eastern Oklahoma... By Saturday morning/the start of the Day 2 period, the aforementioned western U.S. upper low will be in the process of deepening, as a strong (100-plus kt) mid-level jet streak shifts across Arizona/New Mexico into the southern High Plains early in the day. In response to the deepening low, surface cyclogenesis is expected into the afternoon across the Colorado/Kansas/Nebraska border region, with continued through the evening as the low shifts into western/central Nebraska. Despite a lack of moisture, daytime heating combined with steep lapse rates aloft will result in modest afternoon destabilization, with roughly 500 J/kg mixed-layer CAPE expected to develop just ahead of the evolving surface low, from southwestern Nebraska east-southeastward northern Kansas, and then southward into the southern Plains. By mid afternoon, low-topped storm development is expected, as strong ascent focused near the near the surface low, and the cold/occluded front extending east-southeastward across southern Nebraska. Storms should be initially cellular, but are likely to grow upscale into an arcing line, that may eventually extend southward into eastern Oklahoma and possibly northeastern Texas. With strongly backed low-level flow, veering with height, shear will be sufficient to support rotating updrafts -- particularly across the Nebraska portion of the risk area. Here, locally damaging wind gusts and hail in the inch to inch-and-a-half range may occur in roughly the 3PM to 7PM time frame, along with potential for a couple of brief tornadoes. Tornado threat should remain limited due to dewpoints expected to remain only in the low to mid 40s. With the loss of diurnal heating, an evening convective weakening trend is expected, with severe risk likely to have diminished to minimal levels by late evening. ..Goss.. 04/05/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1227 PM CDT Fri Apr 05 2024 Valid 061200Z - 071200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM SOUTHWESTERN AND CENTRAL NEBRASKA INTO PORTIONS OF CENTRAL AND EASTERN KANSAS... ...SUMMARY... Strong/locally severe storms, capable of producing hail and strong wind gusts, will be possible across parts of the central and southern Plains Saturday afternoon and evening. A brief tornado or two may also occur. ...Synopsis... While an upper low will continue to linger just off the New England coast, the more substantial system with respect to potentially severe convection will be a second low, shifting across the western U.S. through the Day 1 time period and then into the central Plains Saturday and Saturday night. At the surface, a developing low will shift into the central Plains through the second half of the period, with a cold front to shift eastward into/across the central and southern Plains through the period. ...Western Nebraska across central and eastern Kansas, and into eastern Oklahoma... By Saturday morning/the start of the Day 2 period, the aforementioned western U.S. upper low will be in the process of deepening, as a strong (100-plus kt) mid-level jet streak shifts across Arizona/New Mexico into the southern High Plains early in the day. In response to the deepening low, surface cyclogenesis is expected into the afternoon across the Colorado/Kansas/Nebraska border region, with continued through the evening as the low shifts into western/central Nebraska. Despite a lack of moisture, daytime heating combined with steep lapse rates aloft will result in modest afternoon destabilization, with roughly 500 J/kg mixed-layer CAPE expected to develop just ahead of the evolving surface low, from southwestern Nebraska east-southeastward northern Kansas, and then southward into the southern Plains. By mid afternoon, low-topped storm development is expected, as strong ascent focused near the near the surface low, and the cold/occluded front extending east-southeastward across southern Nebraska. Storms should be initially cellular, but are likely to grow upscale into an arcing line, that may eventually extend southward into eastern Oklahoma and possibly northeastern Texas. With strongly backed low-level flow, veering with height, shear will be sufficient to support rotating updrafts -- particularly across the Nebraska portion of the risk area. Here, locally damaging wind gusts and hail in the inch to inch-and-a-half range may occur in roughly the 3PM to 7PM time frame, along with potential for a couple of brief tornadoes. Tornado threat should remain limited due to dewpoints expected to remain only in the low to mid 40s. With the loss of diurnal heating, an evening convective weakening trend is expected, with severe risk likely to have diminished to minimal levels by late evening. ..Goss.. 04/05/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1227 PM CDT Fri Apr 05 2024 Valid 061200Z - 071200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM SOUTHWESTERN AND CENTRAL NEBRASKA INTO PORTIONS OF CENTRAL AND EASTERN KANSAS... ...SUMMARY... Strong/locally severe storms, capable of producing hail and strong wind gusts, will be possible across parts of the central and southern Plains Saturday afternoon and evening. A brief tornado or two may also occur. ...Synopsis... While an upper low will continue to linger just off the New England coast, the more substantial system with respect to potentially severe convection will be a second low, shifting across the western U.S. through the Day 1 time period and then into the central Plains Saturday and Saturday night. At the surface, a developing low will shift into the central Plains through the second half of the period, with a cold front to shift eastward into/across the central and southern Plains through the period. ...Western Nebraska across central and eastern Kansas, and into eastern Oklahoma... By Saturday morning/the start of the Day 2 period, the aforementioned western U.S. upper low will be in the process of deepening, as a strong (100-plus kt) mid-level jet streak shifts across Arizona/New Mexico into the southern High Plains early in the day. In response to the deepening low, surface cyclogenesis is expected into the afternoon across the Colorado/Kansas/Nebraska border region, with continued through the evening as the low shifts into western/central Nebraska. Despite a lack of moisture, daytime heating combined with steep lapse rates aloft will result in modest afternoon destabilization, with roughly 500 J/kg mixed-layer CAPE expected to develop just ahead of the evolving surface low, from southwestern Nebraska east-southeastward northern Kansas, and then southward into the southern Plains. By mid afternoon, low-topped storm development is expected, as strong ascent focused near the near the surface low, and the cold/occluded front extending east-southeastward across southern Nebraska. Storms should be initially cellular, but are likely to grow upscale into an arcing line, that may eventually extend southward into eastern Oklahoma and possibly northeastern Texas. With strongly backed low-level flow, veering with height, shear will be sufficient to support rotating updrafts -- particularly across the Nebraska portion of the risk area. Here, locally damaging wind gusts and hail in the inch to inch-and-a-half range may occur in roughly the 3PM to 7PM time frame, along with potential for a couple of brief tornadoes. Tornado threat should remain limited due to dewpoints expected to remain only in the low to mid 40s. With the loss of diurnal heating, an evening convective weakening trend is expected, with severe risk likely to have diminished to minimal levels by late evening. ..Goss.. 04/05/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1227 PM CDT Fri Apr 05 2024 Valid 061200Z - 071200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM SOUTHWESTERN AND CENTRAL NEBRASKA INTO PORTIONS OF CENTRAL AND EASTERN KANSAS... ...SUMMARY... Strong/locally severe storms, capable of producing hail and strong wind gusts, will be possible across parts of the central and southern Plains Saturday afternoon and evening. A brief tornado or two may also occur. ...Synopsis... While an upper low will continue to linger just off the New England coast, the more substantial system with respect to potentially severe convection will be a second low, shifting across the western U.S. through the Day 1 time period and then into the central Plains Saturday and Saturday night. At the surface, a developing low will shift into the central Plains through the second half of the period, with a cold front to shift eastward into/across the central and southern Plains through the period. ...Western Nebraska across central and eastern Kansas, and into eastern Oklahoma... By Saturday morning/the start of the Day 2 period, the aforementioned western U.S. upper low will be in the process of deepening, as a strong (100-plus kt) mid-level jet streak shifts across Arizona/New Mexico into the southern High Plains early in the day. In response to the deepening low, surface cyclogenesis is expected into the afternoon across the Colorado/Kansas/Nebraska border region, with continued through the evening as the low shifts into western/central Nebraska. Despite a lack of moisture, daytime heating combined with steep lapse rates aloft will result in modest afternoon destabilization, with roughly 500 J/kg mixed-layer CAPE expected to develop just ahead of the evolving surface low, from southwestern Nebraska east-southeastward northern Kansas, and then southward into the southern Plains. By mid afternoon, low-topped storm development is expected, as strong ascent focused near the near the surface low, and the cold/occluded front extending east-southeastward across southern Nebraska. Storms should be initially cellular, but are likely to grow upscale into an arcing line, that may eventually extend southward into eastern Oklahoma and possibly northeastern Texas. With strongly backed low-level flow, veering with height, shear will be sufficient to support rotating updrafts -- particularly across the Nebraska portion of the risk area. Here, locally damaging wind gusts and hail in the inch to inch-and-a-half range may occur in roughly the 3PM to 7PM time frame, along with potential for a couple of brief tornadoes. Tornado threat should remain limited due to dewpoints expected to remain only in the low to mid 40s. With the loss of diurnal heating, an evening convective weakening trend is expected, with severe risk likely to have diminished to minimal levels by late evening. ..Goss.. 04/05/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1227 PM CDT Fri Apr 05 2024 Valid 061200Z - 071200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM SOUTHWESTERN AND CENTRAL NEBRASKA INTO PORTIONS OF CENTRAL AND EASTERN KANSAS... ...SUMMARY... Strong/locally severe storms, capable of producing hail and strong wind gusts, will be possible across parts of the central and southern Plains Saturday afternoon and evening. A brief tornado or two may also occur. ...Synopsis... While an upper low will continue to linger just off the New England coast, the more substantial system with respect to potentially severe convection will be a second low, shifting across the western U.S. through the Day 1 time period and then into the central Plains Saturday and Saturday night. At the surface, a developing low will shift into the central Plains through the second half of the period, with a cold front to shift eastward into/across the central and southern Plains through the period. ...Western Nebraska across central and eastern Kansas, and into eastern Oklahoma... By Saturday morning/the start of the Day 2 period, the aforementioned western U.S. upper low will be in the process of deepening, as a strong (100-plus kt) mid-level jet streak shifts across Arizona/New Mexico into the southern High Plains early in the day. In response to the deepening low, surface cyclogenesis is expected into the afternoon across the Colorado/Kansas/Nebraska border region, with continued through the evening as the low shifts into western/central Nebraska. Despite a lack of moisture, daytime heating combined with steep lapse rates aloft will result in modest afternoon destabilization, with roughly 500 J/kg mixed-layer CAPE expected to develop just ahead of the evolving surface low, from southwestern Nebraska east-southeastward northern Kansas, and then southward into the southern Plains. By mid afternoon, low-topped storm development is expected, as strong ascent focused near the near the surface low, and the cold/occluded front extending east-southeastward across southern Nebraska. Storms should be initially cellular, but are likely to grow upscale into an arcing line, that may eventually extend southward into eastern Oklahoma and possibly northeastern Texas. With strongly backed low-level flow, veering with height, shear will be sufficient to support rotating updrafts -- particularly across the Nebraska portion of the risk area. Here, locally damaging wind gusts and hail in the inch to inch-and-a-half range may occur in roughly the 3PM to 7PM time frame, along with potential for a couple of brief tornadoes. Tornado threat should remain limited due to dewpoints expected to remain only in the low to mid 40s. With the loss of diurnal heating, an evening convective weakening trend is expected, with severe risk likely to have diminished to minimal levels by late evening. ..Goss.. 04/05/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1227 PM CDT Fri Apr 05 2024 Valid 061200Z - 071200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM SOUTHWESTERN AND CENTRAL NEBRASKA INTO PORTIONS OF CENTRAL AND EASTERN KANSAS... ...SUMMARY... Strong/locally severe storms, capable of producing hail and strong wind gusts, will be possible across parts of the central and southern Plains Saturday afternoon and evening. A brief tornado or two may also occur. ...Synopsis... While an upper low will continue to linger just off the New England coast, the more substantial system with respect to potentially severe convection will be a second low, shifting across the western U.S. through the Day 1 time period and then into the central Plains Saturday and Saturday night. At the surface, a developing low will shift into the central Plains through the second half of the period, with a cold front to shift eastward into/across the central and southern Plains through the period. ...Western Nebraska across central and eastern Kansas, and into eastern Oklahoma... By Saturday morning/the start of the Day 2 period, the aforementioned western U.S. upper low will be in the process of deepening, as a strong (100-plus kt) mid-level jet streak shifts across Arizona/New Mexico into the southern High Plains early in the day. In response to the deepening low, surface cyclogenesis is expected into the afternoon across the Colorado/Kansas/Nebraska border region, with continued through the evening as the low shifts into western/central Nebraska. Despite a lack of moisture, daytime heating combined with steep lapse rates aloft will result in modest afternoon destabilization, with roughly 500 J/kg mixed-layer CAPE expected to develop just ahead of the evolving surface low, from southwestern Nebraska east-southeastward northern Kansas, and then southward into the southern Plains. By mid afternoon, low-topped storm development is expected, as strong ascent focused near the near the surface low, and the cold/occluded front extending east-southeastward across southern Nebraska. Storms should be initially cellular, but are likely to grow upscale into an arcing line, that may eventually extend southward into eastern Oklahoma and possibly northeastern Texas. With strongly backed low-level flow, veering with height, shear will be sufficient to support rotating updrafts -- particularly across the Nebraska portion of the risk area. Here, locally damaging wind gusts and hail in the inch to inch-and-a-half range may occur in roughly the 3PM to 7PM time frame, along with potential for a couple of brief tornadoes. Tornado threat should remain limited due to dewpoints expected to remain only in the low to mid 40s. With the loss of diurnal heating, an evening convective weakening trend is expected, with severe risk likely to have diminished to minimal levels by late evening. ..Goss.. 04/05/2024 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1148 AM CDT Fri Apr 05 2024 Valid 051700Z - 061200Z ...CRITICAL FIRE WEATHER AREA FOR THE SOUTHERN TO CENTRAL HIGH PLAINS... No changes are needed to the current D1 Fire Weather Outlook. Critical fire weather conditions are expected across the southern to central High Plains this afternoon. Morning visible satellite imagery shows mostly sunny conditions across much of western Texas and southern New Mexico with broken high clouds into northern New Mexico/Colorado/Texas Panhandle. Humidity across the Critical region is largely below 20 percent as of 16z, with winds gusting 30-40 mph. While some increase in high clouds is expected through the day, daytime heating and mixing will support further relative humidity reductions, dropping as low as 10-15%. As previously mentioned, localized areas of Extremely Critical fire weather will be possible, most likely over east-central Colorado. Given the low confidence in coverage of these conditions, the current outlook covers the threat appropriately with no updates needed. ..Thornton.. 04/05/2024 .PREV DISCUSSION... /ISSUED 0119 AM CDT Fri Apr 05 2024/ ...Synopsis... ...Southern to Central High Plains... Today will be the first of two days of widespread critical fire weather conditions - particularly across the southern High Plains. Early-morning surface observations are showing poor overnight RH recovery (10-30% as of 06 UTC) across southeast NM and west/southwest TX to eastern CO. No appreciable moisture return will maintain this unseasonably dry air mass (dewpoints near the 10th percentile for early April) over the next two days. Meanwhile across the West Coast, a strong upper-level trough is noted in water-vapor imagery moving onto the CA coast. Slow, but steady pressure falls are noted along the High Plains as this feature shifts east, with a more robust low-level mass response anticipated through the day. This will promote widespread sustained winds between 20-25 mph (gusting to 35-45 mph) across the southern to central High Plains. Latest ensemble guidance suggests RH values will fall into the 10-15% range for most locations, though localized areas of single-digit RH is possible. This will most likely occur over areas that can maintain mostly clear skies through mid/late afternoon, allowing for stronger surface heating and deeper boundary-layer mixing. Confidence in the coverage of sub-10% RH is limited based on spread in recent guidance, but recent high-res solutions suggests this may be most likely over east-central CO. Consequently, pockets of extremely critical conditions are possible with more widespread, sustained critical conditions expected. Recent fuel analyses show that 1 and 10-hour fuels are either currently receptive or should see sufficient drying to support the fire weather threat. ...Wyoming into Montana... Elevated to locally critical fire weather conditions are expected across eastern to northeast WY and southeast MT this afternoon. Surface pressure falls across the northern High Plains should promote a strengthening pressure gradient and widespread 15-25 mph winds with afternoon RH minimums in the 15-25% range. Additionally, a modest influx of mid-level moisture coupled with broad scale ascent may support a few isolated thunderstorms. Given the dry, deeply-mixed boundary layers over the region and PWAT values well below 0.5 inch, a few dry thunderstorms are possible. ...North Dakota... Sustained winds between 20-25 mph appear likely across much of central ND this afternoon. Dry conditions were noted yesterday across this region, and limited moisture return, coupled with diurnal heating, should promote RH reductions into the 20-30% range this afternoon. Elevated to locally critical fire weather conditions are expected, but modest fuel receptiveness precludes higher risk 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 1148 AM CDT Fri Apr 05 2024 Valid 051700Z - 061200Z ...CRITICAL FIRE WEATHER AREA FOR THE SOUTHERN TO CENTRAL HIGH PLAINS... No changes are needed to the current D1 Fire Weather Outlook. Critical fire weather conditions are expected across the southern to central High Plains this afternoon. Morning visible satellite imagery shows mostly sunny conditions across much of western Texas and southern New Mexico with broken high clouds into northern New Mexico/Colorado/Texas Panhandle. Humidity across the Critical region is largely below 20 percent as of 16z, with winds gusting 30-40 mph. While some increase in high clouds is expected through the day, daytime heating and mixing will support further relative humidity reductions, dropping as low as 10-15%. As previously mentioned, localized areas of Extremely Critical fire weather will be possible, most likely over east-central Colorado. Given the low confidence in coverage of these conditions, the current outlook covers the threat appropriately with no updates needed. ..Thornton.. 04/05/2024 .PREV DISCUSSION... /ISSUED 0119 AM CDT Fri Apr 05 2024/ ...Synopsis... ...Southern to Central High Plains... Today will be the first of two days of widespread critical fire weather conditions - particularly across the southern High Plains. Early-morning surface observations are showing poor overnight RH recovery (10-30% as of 06 UTC) across southeast NM and west/southwest TX to eastern CO. No appreciable moisture return will maintain this unseasonably dry air mass (dewpoints near the 10th percentile for early April) over the next two days. Meanwhile across the West Coast, a strong upper-level trough is noted in water-vapor imagery moving onto the CA coast. Slow, but steady pressure falls are noted along the High Plains as this feature shifts east, with a more robust low-level mass response anticipated through the day. This will promote widespread sustained winds between 20-25 mph (gusting to 35-45 mph) across the southern to central High Plains. Latest ensemble guidance suggests RH values will fall into the 10-15% range for most locations, though localized areas of single-digit RH is possible. This will most likely occur over areas that can maintain mostly clear skies through mid/late afternoon, allowing for stronger surface heating and deeper boundary-layer mixing. Confidence in the coverage of sub-10% RH is limited based on spread in recent guidance, but recent high-res solutions suggests this may be most likely over east-central CO. Consequently, pockets of extremely critical conditions are possible with more widespread, sustained critical conditions expected. Recent fuel analyses show that 1 and 10-hour fuels are either currently receptive or should see sufficient drying to support the fire weather threat. ...Wyoming into Montana... Elevated to locally critical fire weather conditions are expected across eastern to northeast WY and southeast MT this afternoon. Surface pressure falls across the northern High Plains should promote a strengthening pressure gradient and widespread 15-25 mph winds with afternoon RH minimums in the 15-25% range. Additionally, a modest influx of mid-level moisture coupled with broad scale ascent may support a few isolated thunderstorms. Given the dry, deeply-mixed boundary layers over the region and PWAT values well below 0.5 inch, a few dry thunderstorms are possible. ...North Dakota... Sustained winds between 20-25 mph appear likely across much of central ND this afternoon. Dry conditions were noted yesterday across this region, and limited moisture return, coupled with diurnal heating, should promote RH reductions into the 20-30% range this afternoon. Elevated to locally critical fire weather conditions are expected, but modest fuel receptiveness precludes higher risk highlights. ...Please see www.spc.noaa.gov/fire for graphic product... Read more