Severe Storms

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1251 AM CDT Fri Sep 20 2019 Valid 211200Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM CENTRAL KANSAS INTO IOWA... ...SUMMARY... Severe storms are possible across parts of the Plains on Saturday, most concentrated from Kansas into Iowa. Other isolated activity is expected across Minnesota, and over parts of the southern High Plains. ...Synopsis... An upper trough will move east across the northern Plains and toward the Great Lakes, with a broad zone of strong upper-level southwesterlies encompassing the central and northern Plains, upper MS valley and Great Lakes. The primary surface trough will extend from northern ND and MN into Ontario, with a cold front roughly from central MN into western KS by Saturday afternoon. Ahead of the front, mid to upper 60s F dewpoints will be widespread, and will contribute to areas of moderate instability. The most favorable combination of instability, lift, and shear will extend from KS into IA, while isolated severe storm potential exists farther north into MN and WI. ...Central Plains... The tail end of the cold front is expected to stall over western KS, allowing for substantial heating. Upper 60s F dewpoints are expected south of the front which will extend from western KS into southeast NE and into IA, and will contribute to strong instability. Height falls will be gradual over the central Plains, but mid to upper level winds will become strong with very long hodographs forecast due to a 100 kt upper jet. In addition, low-level winds will remain southerly, and will support supercells along the front. Very large hail and a couple tornadoes will be possible during the afternoon and evening. With time, storms should merge along the front, with a developing damaging wind threat from KS into northern MO. ...Far eastern Dakotas across MN and into WI... Scattered storms are expected to be ongoing Saturday morning over ND, parts of MN and WI as large-scale lift overspreads the area. Hail or wind will be possible with this activity. By afternoon, the cold front will move into western MN, and ample instability and deep-layer shear will support further severe storms, although low-level winds will veer with time with drying aloft as well. Long hodographs and steepening lapse rates aloft will conditionally favor large hail, most likely over northwest MN beneath cold temperatures aloft. Storm coverage along the front farther south across MN and into WI is less certain due to capping. As such, will maintain 5% probabilities for isolated severe coverage, but greater probabilities may be needed in later outlooks if more storms are expected. ...MAXIMUM RISK BY HAZARD... Tornado: 5% - Slight Wind: 15% - Slight Hail: 15% SIG - Slight ..Jewell.. 09/20/2019 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1251 AM CDT Fri Sep 20 2019 Valid 211200Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM CENTRAL KANSAS INTO IOWA... ...SUMMARY... Severe storms are possible across parts of the Plains on Saturday, most concentrated from Kansas into Iowa. Other isolated activity is expected across Minnesota, and over parts of the southern High Plains. ...Synopsis... An upper trough will move east across the northern Plains and toward the Great Lakes, with a broad zone of strong upper-level southwesterlies encompassing the central and northern Plains, upper MS valley and Great Lakes. The primary surface trough will extend from northern ND and MN into Ontario, with a cold front roughly from central MN into western KS by Saturday afternoon. Ahead of the front, mid to upper 60s F dewpoints will be widespread, and will contribute to areas of moderate instability. The most favorable combination of instability, lift, and shear will extend from KS into IA, while isolated severe storm potential exists farther north into MN and WI. ...Central Plains... The tail end of the cold front is expected to stall over western KS, allowing for substantial heating. Upper 60s F dewpoints are expected south of the front which will extend from western KS into southeast NE and into IA, and will contribute to strong instability. Height falls will be gradual over the central Plains, but mid to upper level winds will become strong with very long hodographs forecast due to a 100 kt upper jet. In addition, low-level winds will remain southerly, and will support supercells along the front. Very large hail and a couple tornadoes will be possible during the afternoon and evening. With time, storms should merge along the front, with a developing damaging wind threat from KS into northern MO. ...Far eastern Dakotas across MN and into WI... Scattered storms are expected to be ongoing Saturday morning over ND, parts of MN and WI as large-scale lift overspreads the area. Hail or wind will be possible with this activity. By afternoon, the cold front will move into western MN, and ample instability and deep-layer shear will support further severe storms, although low-level winds will veer with time with drying aloft as well. Long hodographs and steepening lapse rates aloft will conditionally favor large hail, most likely over northwest MN beneath cold temperatures aloft. Storm coverage along the front farther south across MN and into WI is less certain due to capping. As such, will maintain 5% probabilities for isolated severe coverage, but greater probabilities may be needed in later outlooks if more storms are expected. ...MAXIMUM RISK BY HAZARD... Tornado: 5% - Slight Wind: 15% - Slight Hail: 15% SIG - Slight ..Jewell.. 09/20/2019 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1251 AM CDT Fri Sep 20 2019 Valid 211200Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM CENTRAL KANSAS INTO IOWA... ...SUMMARY... Severe storms are possible across parts of the Plains on Saturday, most concentrated from Kansas into Iowa. Other isolated activity is expected across Minnesota, and over parts of the southern High Plains. ...Synopsis... An upper trough will move east across the northern Plains and toward the Great Lakes, with a broad zone of strong upper-level southwesterlies encompassing the central and northern Plains, upper MS valley and Great Lakes. The primary surface trough will extend from northern ND and MN into Ontario, with a cold front roughly from central MN into western KS by Saturday afternoon. Ahead of the front, mid to upper 60s F dewpoints will be widespread, and will contribute to areas of moderate instability. The most favorable combination of instability, lift, and shear will extend from KS into IA, while isolated severe storm potential exists farther north into MN and WI. ...Central Plains... The tail end of the cold front is expected to stall over western KS, allowing for substantial heating. Upper 60s F dewpoints are expected south of the front which will extend from western KS into southeast NE and into IA, and will contribute to strong instability. Height falls will be gradual over the central Plains, but mid to upper level winds will become strong with very long hodographs forecast due to a 100 kt upper jet. In addition, low-level winds will remain southerly, and will support supercells along the front. Very large hail and a couple tornadoes will be possible during the afternoon and evening. With time, storms should merge along the front, with a developing damaging wind threat from KS into northern MO. ...Far eastern Dakotas across MN and into WI... Scattered storms are expected to be ongoing Saturday morning over ND, parts of MN and WI as large-scale lift overspreads the area. Hail or wind will be possible with this activity. By afternoon, the cold front will move into western MN, and ample instability and deep-layer shear will support further severe storms, although low-level winds will veer with time with drying aloft as well. Long hodographs and steepening lapse rates aloft will conditionally favor large hail, most likely over northwest MN beneath cold temperatures aloft. Storm coverage along the front farther south across MN and into WI is less certain due to capping. As such, will maintain 5% probabilities for isolated severe coverage, but greater probabilities may be needed in later outlooks if more storms are expected. ...MAXIMUM RISK BY HAZARD... Tornado: 5% - Slight Wind: 15% - Slight Hail: 15% SIG - Slight ..Jewell.. 09/20/2019 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Fri Sep 20 2019 Valid 211200Z - 221200Z ...NO CRITICAL AREAS... ...Synopsis... The upper-level trough located over the central/northern Plains should flatten while developing two short-wave troughs that pivot through the region. Meanwhile, ridging will develop over the upper Great Basin. These processes should keep most of the enhanced mid-level flow juxtaposed to the east of areas where fuels are currently receptive, and thus, fire-weather concerns remain low at this time. With that said, there exists some potential for perhaps localized elevated conditions to develop over portions of south-central Colorado/far north-central New Mexico. However, considerable spread is present among various model guidance concerning the RH/wind overlap/potential, and thus no highlights have been included at this time. ..Karstens.. 09/20/2019 ...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 0100 AM CDT Fri Sep 20 2019 Valid 211200Z - 221200Z ...NO CRITICAL AREAS... ...Synopsis... The upper-level trough located over the central/northern Plains should flatten while developing two short-wave troughs that pivot through the region. Meanwhile, ridging will develop over the upper Great Basin. These processes should keep most of the enhanced mid-level flow juxtaposed to the east of areas where fuels are currently receptive, and thus, fire-weather concerns remain low at this time. With that said, there exists some potential for perhaps localized elevated conditions to develop over portions of south-central Colorado/far north-central New Mexico. However, considerable spread is present among various model guidance concerning the RH/wind overlap/potential, and thus no highlights have been included at this time. ..Karstens.. 09/20/2019 ...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 0100 AM CDT Fri Sep 20 2019 Valid 211200Z - 221200Z ...NO CRITICAL AREAS... ...Synopsis... The upper-level trough located over the central/northern Plains should flatten while developing two short-wave troughs that pivot through the region. Meanwhile, ridging will develop over the upper Great Basin. These processes should keep most of the enhanced mid-level flow juxtaposed to the east of areas where fuels are currently receptive, and thus, fire-weather concerns remain low at this time. With that said, there exists some potential for perhaps localized elevated conditions to develop over portions of south-central Colorado/far north-central New Mexico. However, considerable spread is present among various model guidance concerning the RH/wind overlap/potential, and thus no highlights have been included at this time. ..Karstens.. 09/20/2019 ...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 0100 AM CDT Fri Sep 20 2019 Valid 211200Z - 221200Z ...NO CRITICAL AREAS... ...Synopsis... The upper-level trough located over the central/northern Plains should flatten while developing two short-wave troughs that pivot through the region. Meanwhile, ridging will develop over the upper Great Basin. These processes should keep most of the enhanced mid-level flow juxtaposed to the east of areas where fuels are currently receptive, and thus, fire-weather concerns remain low at this time. With that said, there exists some potential for perhaps localized elevated conditions to develop over portions of south-central Colorado/far north-central New Mexico. However, considerable spread is present among various model guidance concerning the RH/wind overlap/potential, and thus no highlights have been included at this time. ..Karstens.. 09/20/2019 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1255 AM CDT Fri Sep 20 2019 Valid 201200Z - 211200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS INTO PARTS OF THE CENTRAL HIGH PLAINS... ...SUMMARY... Scattered severe storms associated with wind damage, isolated large hail and a couple tornadoes are possible today across the northern Plains, with marginally severe storms possible in parts of the central and southern High Plains. ...Northern Plains... An upper-level low will move northeastward into the northern Rockies today as an associated trough moves across the Intermountain West. Ahead of the system, south-southwesterly mid-level flow will be located across much of the central and northern Plains. Strengthening low-level flow ahead of the system will help to reinforce a moist airmass from the Dakotas eastward across Minnesota. A cold front will advance eastward into the western Dakotas today where thunderstorm development may take place along the front early this afternoon. Thunderstorms are expected to increase in coverage as the front moves eastward across the central Dakotas late this afternoon. Additional thunderstorms may develop in the post-frontal airmass in southeast Montana and northeast Wyoming. As convective coverage maximizes in the evening, linear MCS development will be possible from far northwest Minnesota southwestward into south-central North Dakota and west-central South Dakota. Concerning the severe weather potential, surface dewpoints by afternoon should range from the mid 60s F in the central Dakotas to the lower 70s in central Minnesota. In response, moderate to strong instability is forecast to develop by late afternoon with MLCAPE values reaching 3000 to 4000 J/kg in some locations ahead of the front. Forecast soundings along the western edge of the strongest instability show moderate deep-layer shear profiles with 0-6 km shear in the 30 to 40 kt range. This should support an organized severe threat from late afternoon throughout the evening. Although supercells with isolated large hail will be possible with storms that remain discrete, the more dominant mode is expected to be linear as an MCS forms along and ahead of the front. Wind damage will be possible along the leading edge of the squall-line. An isolated tornado threat may also occur with any supercell that can develop or with rotating cells embedded in the line. The squall-line is forecast to move across northwestern Minnesota, eastern North Dakota and central South Dakota during the evening and continue moving slowly eastward through the overnight period. ...Southern and Central High Plains... Southwest mid-level flow will be in place today across the southern and central Plains. At the surface, a lee trough will deepen across eastern Colorado and eastern New Mexico. To the east of the trough, surface dewpoints should range form the mid 60s F in western Kansas to the lower 70s in the southeastern Texas Panhandle. In response to the moist airmass, a north-to-south corridor of moderate instability is expected to develop by early afternoon. Model forecasts suggest that thunderstorm development will be most likely on the southern end of the strongest instability from the southern Texas Panhandle into parts of west Texas where low-level convergence should be enhanced. NAM forecast soundings at Amarillo and Lubbock by late afternoon show MLCAPE peaking around 1500 J/kg. In addition, 0-6 km shear values are forecast to be in the 35 to 45 kt range. This environment suggests that isolated severe storms with hail and strong gusty winds will be possible. The amount of instability is expected to be too marginal for a more substantial severe threat. ..Broyles/Karstens.. 09/20/2019 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1255 AM CDT Fri Sep 20 2019 Valid 201200Z - 211200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS INTO PARTS OF THE CENTRAL HIGH PLAINS... ...SUMMARY... Scattered severe storms associated with wind damage, isolated large hail and a couple tornadoes are possible today across the northern Plains, with marginally severe storms possible in parts of the central and southern High Plains. ...Northern Plains... An upper-level low will move northeastward into the northern Rockies today as an associated trough moves across the Intermountain West. Ahead of the system, south-southwesterly mid-level flow will be located across much of the central and northern Plains. Strengthening low-level flow ahead of the system will help to reinforce a moist airmass from the Dakotas eastward across Minnesota. A cold front will advance eastward into the western Dakotas today where thunderstorm development may take place along the front early this afternoon. Thunderstorms are expected to increase in coverage as the front moves eastward across the central Dakotas late this afternoon. Additional thunderstorms may develop in the post-frontal airmass in southeast Montana and northeast Wyoming. As convective coverage maximizes in the evening, linear MCS development will be possible from far northwest Minnesota southwestward into south-central North Dakota and west-central South Dakota. Concerning the severe weather potential, surface dewpoints by afternoon should range from the mid 60s F in the central Dakotas to the lower 70s in central Minnesota. In response, moderate to strong instability is forecast to develop by late afternoon with MLCAPE values reaching 3000 to 4000 J/kg in some locations ahead of the front. Forecast soundings along the western edge of the strongest instability show moderate deep-layer shear profiles with 0-6 km shear in the 30 to 40 kt range. This should support an organized severe threat from late afternoon throughout the evening. Although supercells with isolated large hail will be possible with storms that remain discrete, the more dominant mode is expected to be linear as an MCS forms along and ahead of the front. Wind damage will be possible along the leading edge of the squall-line. An isolated tornado threat may also occur with any supercell that can develop or with rotating cells embedded in the line. The squall-line is forecast to move across northwestern Minnesota, eastern North Dakota and central South Dakota during the evening and continue moving slowly eastward through the overnight period. ...Southern and Central High Plains... Southwest mid-level flow will be in place today across the southern and central Plains. At the surface, a lee trough will deepen across eastern Colorado and eastern New Mexico. To the east of the trough, surface dewpoints should range form the mid 60s F in western Kansas to the lower 70s in the southeastern Texas Panhandle. In response to the moist airmass, a north-to-south corridor of moderate instability is expected to develop by early afternoon. Model forecasts suggest that thunderstorm development will be most likely on the southern end of the strongest instability from the southern Texas Panhandle into parts of west Texas where low-level convergence should be enhanced. NAM forecast soundings at Amarillo and Lubbock by late afternoon show MLCAPE peaking around 1500 J/kg. In addition, 0-6 km shear values are forecast to be in the 35 to 45 kt range. This environment suggests that isolated severe storms with hail and strong gusty winds will be possible. The amount of instability is expected to be too marginal for a more substantial severe threat. ..Broyles/Karstens.. 09/20/2019 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1255 AM CDT Fri Sep 20 2019 Valid 201200Z - 211200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS INTO PARTS OF THE CENTRAL HIGH PLAINS... ...SUMMARY... Scattered severe storms associated with wind damage, isolated large hail and a couple tornadoes are possible today across the northern Plains, with marginally severe storms possible in parts of the central and southern High Plains. ...Northern Plains... An upper-level low will move northeastward into the northern Rockies today as an associated trough moves across the Intermountain West. Ahead of the system, south-southwesterly mid-level flow will be located across much of the central and northern Plains. Strengthening low-level flow ahead of the system will help to reinforce a moist airmass from the Dakotas eastward across Minnesota. A cold front will advance eastward into the western Dakotas today where thunderstorm development may take place along the front early this afternoon. Thunderstorms are expected to increase in coverage as the front moves eastward across the central Dakotas late this afternoon. Additional thunderstorms may develop in the post-frontal airmass in southeast Montana and northeast Wyoming. As convective coverage maximizes in the evening, linear MCS development will be possible from far northwest Minnesota southwestward into south-central North Dakota and west-central South Dakota. Concerning the severe weather potential, surface dewpoints by afternoon should range from the mid 60s F in the central Dakotas to the lower 70s in central Minnesota. In response, moderate to strong instability is forecast to develop by late afternoon with MLCAPE values reaching 3000 to 4000 J/kg in some locations ahead of the front. Forecast soundings along the western edge of the strongest instability show moderate deep-layer shear profiles with 0-6 km shear in the 30 to 40 kt range. This should support an organized severe threat from late afternoon throughout the evening. Although supercells with isolated large hail will be possible with storms that remain discrete, the more dominant mode is expected to be linear as an MCS forms along and ahead of the front. Wind damage will be possible along the leading edge of the squall-line. An isolated tornado threat may also occur with any supercell that can develop or with rotating cells embedded in the line. The squall-line is forecast to move across northwestern Minnesota, eastern North Dakota and central South Dakota during the evening and continue moving slowly eastward through the overnight period. ...Southern and Central High Plains... Southwest mid-level flow will be in place today across the southern and central Plains. At the surface, a lee trough will deepen across eastern Colorado and eastern New Mexico. To the east of the trough, surface dewpoints should range form the mid 60s F in western Kansas to the lower 70s in the southeastern Texas Panhandle. In response to the moist airmass, a north-to-south corridor of moderate instability is expected to develop by early afternoon. Model forecasts suggest that thunderstorm development will be most likely on the southern end of the strongest instability from the southern Texas Panhandle into parts of west Texas where low-level convergence should be enhanced. NAM forecast soundings at Amarillo and Lubbock by late afternoon show MLCAPE peaking around 1500 J/kg. In addition, 0-6 km shear values are forecast to be in the 35 to 45 kt range. This environment suggests that isolated severe storms with hail and strong gusty winds will be possible. The amount of instability is expected to be too marginal for a more substantial severe threat. ..Broyles/Karstens.. 09/20/2019 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1255 AM CDT Fri Sep 20 2019 Valid 201200Z - 211200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS INTO PARTS OF THE CENTRAL HIGH PLAINS... ...SUMMARY... Scattered severe storms associated with wind damage, isolated large hail and a couple tornadoes are possible today across the northern Plains, with marginally severe storms possible in parts of the central and southern High Plains. ...Northern Plains... An upper-level low will move northeastward into the northern Rockies today as an associated trough moves across the Intermountain West. Ahead of the system, south-southwesterly mid-level flow will be located across much of the central and northern Plains. Strengthening low-level flow ahead of the system will help to reinforce a moist airmass from the Dakotas eastward across Minnesota. A cold front will advance eastward into the western Dakotas today where thunderstorm development may take place along the front early this afternoon. Thunderstorms are expected to increase in coverage as the front moves eastward across the central Dakotas late this afternoon. Additional thunderstorms may develop in the post-frontal airmass in southeast Montana and northeast Wyoming. As convective coverage maximizes in the evening, linear MCS development will be possible from far northwest Minnesota southwestward into south-central North Dakota and west-central South Dakota. Concerning the severe weather potential, surface dewpoints by afternoon should range from the mid 60s F in the central Dakotas to the lower 70s in central Minnesota. In response, moderate to strong instability is forecast to develop by late afternoon with MLCAPE values reaching 3000 to 4000 J/kg in some locations ahead of the front. Forecast soundings along the western edge of the strongest instability show moderate deep-layer shear profiles with 0-6 km shear in the 30 to 40 kt range. This should support an organized severe threat from late afternoon throughout the evening. Although supercells with isolated large hail will be possible with storms that remain discrete, the more dominant mode is expected to be linear as an MCS forms along and ahead of the front. Wind damage will be possible along the leading edge of the squall-line. An isolated tornado threat may also occur with any supercell that can develop or with rotating cells embedded in the line. The squall-line is forecast to move across northwestern Minnesota, eastern North Dakota and central South Dakota during the evening and continue moving slowly eastward through the overnight period. ...Southern and Central High Plains... Southwest mid-level flow will be in place today across the southern and central Plains. At the surface, a lee trough will deepen across eastern Colorado and eastern New Mexico. To the east of the trough, surface dewpoints should range form the mid 60s F in western Kansas to the lower 70s in the southeastern Texas Panhandle. In response to the moist airmass, a north-to-south corridor of moderate instability is expected to develop by early afternoon. Model forecasts suggest that thunderstorm development will be most likely on the southern end of the strongest instability from the southern Texas Panhandle into parts of west Texas where low-level convergence should be enhanced. NAM forecast soundings at Amarillo and Lubbock by late afternoon show MLCAPE peaking around 1500 J/kg. In addition, 0-6 km shear values are forecast to be in the 35 to 45 kt range. This environment suggests that isolated severe storms with hail and strong gusty winds will be possible. The amount of instability is expected to be too marginal for a more substantial severe threat. ..Broyles/Karstens.. 09/20/2019 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1259 AM CDT Fri Sep 20 2019 Valid 201200Z - 211200Z ...CRITICAL FIRE WEATHER AREA FOR THE FOUR CORNERS REGION... ...Synopsis... A highly amplified upper-level trough positioned over the Great Basin will shift east through the Northern Rockies into portions of the central/northern Plains. Enhanced mid-level flow of 60-70 kt will be present within the base of the trough during this progression. At the surface, a broad region of dry and breezy southwesterly winds will develop during the afternoon beneath the mid-level jet. ...Four Corners Region and portions of the central Rockies and central High Plains... Sustained winds of 15-25 mph will develop during the afternoon while RH values fall into the 15-20% range over much of the region. Fuels remain receptive to large-fire spread, and thus, elevated to critical fire-weather conditions are possible. Refinements were made to the existing elevated area over portions of the central High Plans and central Rockies, based on the position of moist boundaries as depicted in the latest high-resolution guidance. A critical area was added near the Four Corners region, where it appears most likely that critical wind/RH thresholds will be exceeded for a few hours during the afternoon. ..Karstens.. 09/20/2019 ...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 1259 AM CDT Fri Sep 20 2019 Valid 201200Z - 211200Z ...CRITICAL FIRE WEATHER AREA FOR THE FOUR CORNERS REGION... ...Synopsis... A highly amplified upper-level trough positioned over the Great Basin will shift east through the Northern Rockies into portions of the central/northern Plains. Enhanced mid-level flow of 60-70 kt will be present within the base of the trough during this progression. At the surface, a broad region of dry and breezy southwesterly winds will develop during the afternoon beneath the mid-level jet. ...Four Corners Region and portions of the central Rockies and central High Plains... Sustained winds of 15-25 mph will develop during the afternoon while RH values fall into the 15-20% range over much of the region. Fuels remain receptive to large-fire spread, and thus, elevated to critical fire-weather conditions are possible. Refinements were made to the existing elevated area over portions of the central High Plans and central Rockies, based on the position of moist boundaries as depicted in the latest high-resolution guidance. A critical area was added near the Four Corners region, where it appears most likely that critical wind/RH thresholds will be exceeded for a few hours during the afternoon. ..Karstens.. 09/20/2019 ...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 1259 AM CDT Fri Sep 20 2019 Valid 201200Z - 211200Z ...CRITICAL FIRE WEATHER AREA FOR THE FOUR CORNERS REGION... ...Synopsis... A highly amplified upper-level trough positioned over the Great Basin will shift east through the Northern Rockies into portions of the central/northern Plains. Enhanced mid-level flow of 60-70 kt will be present within the base of the trough during this progression. At the surface, a broad region of dry and breezy southwesterly winds will develop during the afternoon beneath the mid-level jet. ...Four Corners Region and portions of the central Rockies and central High Plains... Sustained winds of 15-25 mph will develop during the afternoon while RH values fall into the 15-20% range over much of the region. Fuels remain receptive to large-fire spread, and thus, elevated to critical fire-weather conditions are possible. Refinements were made to the existing elevated area over portions of the central High Plans and central Rockies, based on the position of moist boundaries as depicted in the latest high-resolution guidance. A critical area was added near the Four Corners region, where it appears most likely that critical wind/RH thresholds will be exceeded for a few hours during the afternoon. ..Karstens.. 09/20/2019 ...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 1259 AM CDT Fri Sep 20 2019 Valid 201200Z - 211200Z ...CRITICAL FIRE WEATHER AREA FOR THE FOUR CORNERS REGION... ...Synopsis... A highly amplified upper-level trough positioned over the Great Basin will shift east through the Northern Rockies into portions of the central/northern Plains. Enhanced mid-level flow of 60-70 kt will be present within the base of the trough during this progression. At the surface, a broad region of dry and breezy southwesterly winds will develop during the afternoon beneath the mid-level jet. ...Four Corners Region and portions of the central Rockies and central High Plains... Sustained winds of 15-25 mph will develop during the afternoon while RH values fall into the 15-20% range over much of the region. Fuels remain receptive to large-fire spread, and thus, elevated to critical fire-weather conditions are possible. Refinements were made to the existing elevated area over portions of the central High Plans and central Rockies, based on the position of moist boundaries as depicted in the latest high-resolution guidance. A critical area was added near the Four Corners region, where it appears most likely that critical wind/RH thresholds will be exceeded for a few hours during the afternoon. ..Karstens.. 09/20/2019 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0749 PM CDT Thu Sep 19 2019 Valid 200100Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHERN AND CENTRAL HIGH PLAINS... ...SUMMARY... Thunderstorms capable of isolated damaging winds and marginally severe hail will be possible in parts of the central and southern High Plains this evening. ...Central and Southern High Plains... The latest water vapor imagery shows a plume of mid-level moisture from the Texas Panhandle northward into western Kansas and central Nebraska. Scattered thunderstorms are ongoing in this plume where the RAP is suggesting that low-level winds are maximized. Although large-scale ascent is likely weak across the region, a strengthening 30 to 40 kt low-level jet this evening will help convection to continue for several more hours. The airmass from the Texas Panhandle northward into the central High Plains is characterized by low to mid 60s F surface dewpoints and weak to moderate instability (MLCAPE 1000 to 3000 J/kg) according the observed soundings. In addition, regional WSR-88D VWPs at Amarillo, Dodge City and Goodland have 0-6 km shear in the 25 to 35 kt range. With this amount of shear, storm organization is not expected. However, the instability should be great enough for a marginal severe threat with the stronger multicells. Wind damage and hail would be the primary threats. ..Broyles.. 09/20/2019 Read more

No watches are valid as of Thu Sep 19 23:46:02 UTC 2019.

No Mesoscale Discussions are in effect as of Thu Sep 19 23:46:02 UTC 2019.

MD 1986 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR SOUTH-CENTRAL NEBRASKA AND INTO NORTHWEST KANSAS
Mesoscale Discussion 1986 NWS Storm Prediction Center Norman OK 0538 PM CDT Thu Sep 19 2019 Areas affected...south-central Nebraska and into northwest Kansas Concerning...Severe potential...Watch unlikely Valid 192238Z - 192345Z Probability of Watch Issuance...20 percent SUMMARY...Local severe risk is evident across portions of southwestern and into south-central Nebraska, where isolated updrafts have quickly developed. Risk should remain limited in area and duration. DISCUSSION...Latest visible satellite loop shows a couple of intense updrafts which have developed near a subtle/westward-moving gravity wave, that currently arcs from southwest Nebraska southeastward into central Kansas, and then eastward into central Missouri. The thermodynamic environment within which the convection is developing is quite favorable for robust/tall updrafts, given very steep lapse rates aloft and a warm/moist boundary layer combining to yield 3000 to 4000 J/kg mixed-layer CAPE, per recent objective analysis. With that said, deep-layer shear is relatively weak, despite low-level veering, owing to weak westerly winds at mid levels. The relative lack of kinematic contribution to updraft intensity therefore suggests only multicell organization for the most part, with risk for hail and/or wind likely to remain local/isolated. In addition, the threat should remain fairly limited in overall duration, with storms likely to diminish after dark as the boundary layer cools/stabilizes. Until then, hail up to golf ball size, and wind gusts up to or slightly exceeding severe criteria will be possible. ..Goss/Edwards.. 09/19/2019 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...GID...LBF...GLD... LAT...LON 41619871 40219862 39549931 39900073 41320143 41650095 41809987 41619871 Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0255 PM CDT Thu Sep 19 2019 Valid 192000Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS PARTS OF THE SOUTHERN AND CENTRAL HIGH PLAINS...AND OVER PORTIONS OF THE TEXAS COAST... ...SUMMARY... Thunderstorms capable of isolated damaging winds and marginally severe hail will be possible in parts of the central and southern High Plains this afternoon and evening. A brief tornado or two will also be possible near the middle/upper Texas coast. ...20Z Update.. ...Central/Southern High Plains... Thunderstorm coverage is increasing across the region and a few severe thunderstorms are still anticipated. See MCD 1985 for more short-term details. ...LA/TX... TD Imelda remains centered over southeast TX (about 25 miles south of CLL). Tornado threat east/southeast of the center appears limited given the lack of instability. More cellular activity continues southwest of the center over the middle TX Coast. In this area, steep low-level lapse rates are in place, but generally modest low-level shear will keep the tornado potential low. Later this evening, strengthening southeasterly surface winds may contribute to a modest increase in the tornado potential. ..Mosier.. 09/19/2019 .PREV DISCUSSION... /ISSUED 1108 AM CDT Thu Sep 19 2019/ ...High Plains... A large upper trough is present over the western states today, while a broad upper ridge dominates the weather in the east. Southwesterly flow aloft persists over the High Plains, where full sunshine and dewpoints in the 60s will result in steep low-level lapse rates and moderate CAPE. A weak midlevel impulse over NM will likely aid in the development of scattered thunderstorms by mid-afternoon over southeast CO and western portions of the TX/OK Panhandles. This activity will spread northeastward into western KS during the evening. Midlevel winds are relatively weak, which may limit overall organization of the storms. However, potential exists for gusty/damaging winds and hail in the strongest cells through the early evening. ...LA/TX... TD Imelda continues to affect portions of the upper TX and southwest LA coastal region. Transient rotating storms have been noted this morning near the Sabine river. Increasingly discrete convection on the southwest flank of the circulation may also pose a risk of a brief spin-up or two farther south along the upper/middle TX coast later today. Read more