Severe Storms

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1035 AM CST Fri Feb 02 2024 Valid 021700Z - 031200Z ...NO CRITICAL AREAS... ...17z Update... Morning observations showed developing showers/thunderstorms and expanding cloud cover over much of the southern Plains. Some gusty winds and periodic humidity below 25% are possible over parts of southwest TX this afternoon. However, more widespread critical fire-weather concerns appear unlikely owing to wetting rain potential and the poor overlap of meteorological conditions with the driest fuels in southwest TX. See the previous discussion for more information. ..Lyons.. 02/02/2024 .PREV DISCUSSION... /ISSUED 1153 PM CST Thu Feb 01 2024/ ...Synopsis... A mid-level trough will deepen as it ejects into the southern High Plains today, supporting surface cyclone development in Colorado. A dryline will develop and move eastward across the TX Panhandle, supporting strong westerly surface winds through the afternoon hours across eastern New Mexico into far western Texas. While sustained westerly surface winds may exceed 20 mph at times across much of the southern High Plains, widespread clouds with scattered showers and thunderstorms are also expected. When also considering relatively high RH values (20-25 percent at lowest) and marginally receptive fuels, fire weather highlights do not appear warranted at this time. ...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 1035 AM CST Fri Feb 02 2024 Valid 021700Z - 031200Z ...NO CRITICAL AREAS... ...17z Update... Morning observations showed developing showers/thunderstorms and expanding cloud cover over much of the southern Plains. Some gusty winds and periodic humidity below 25% are possible over parts of southwest TX this afternoon. However, more widespread critical fire-weather concerns appear unlikely owing to wetting rain potential and the poor overlap of meteorological conditions with the driest fuels in southwest TX. See the previous discussion for more information. ..Lyons.. 02/02/2024 .PREV DISCUSSION... /ISSUED 1153 PM CST Thu Feb 01 2024/ ...Synopsis... A mid-level trough will deepen as it ejects into the southern High Plains today, supporting surface cyclone development in Colorado. A dryline will develop and move eastward across the TX Panhandle, supporting strong westerly surface winds through the afternoon hours across eastern New Mexico into far western Texas. While sustained westerly surface winds may exceed 20 mph at times across much of the southern High Plains, widespread clouds with scattered showers and thunderstorms are also expected. When also considering relatively high RH values (20-25 percent at lowest) and marginally receptive fuels, fire weather highlights do not appear warranted at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1029 AM CST Fri Feb 02 2024 Valid 021630Z - 031200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM WESTERN NORTH TEXAS AND THE BIG COUNTRY SOUTH TO THE HILL COUNTRY AND EDWARDS PLATEAU... ...SUMMARY... Local severe weather potential, mainly in the form of hail, will affect portions of the southern Plains from late afternoon into this evening. ...Synopsis... A highly amplified upper flow pattern will continue across the U.S. today. While a trough will continue crossing the eastern states and a second affects the Pacific Northwest, the primary feature with respect to convective weather will be a trough/evolving upper low advancing east-southeastward across the Desert Southwest. Ascent in advance of this feature -- and the associated left exit region of a 160 kt northwesterly upper-level jet -- will continue spreading into/across the southern Plains through the period. At the surface, a Pacific cold front -- associated with the aforementioned southwestern U.S. upper trough -- will shift out of eastern New Mexico and far West Texas into lower elevations of the southern Plains today and tonight, in tandem with an increase in thunderstorms across the region. ...Southern Plains... Morning RAOBS indicate stout capping across the southern Plains region, with expansive low clouds/stratus per visible satellite imagery due to a partially modified Gulf boundary-layer airmass streaming northwestward beneath the inversion. The low cloudiness -- and increasing convection across the area with time -- will limit potential for surface-based destabilization in most areas, particularly with eastward extent. With that said, some erosion of the low clouds is ongoing into portions of the Big Country region of Texas, with clear skies to the west -- i.e. portions of the south Plains and the Transpecos region. Resulting insolation ahead of the advancing front will likely permit eventual/afternoon thunderstorm development across the Big Country and Concho Valley region, which is then expected to spread northeastward toward western North Texas with time. Storms may also develop by this evening over the higher terrain just west of the lower Rio Grande Valley, and adjacent portions of the Edwards Plateau. Despite the somewhat cool, and only modestly moist boundary layer expected to persist across the eastern half of the southern Plains, steep lapse rates aloft will contribute to ample CAPE aloft, supporting locally vigorous updrafts. Storm intensity will be aided by favorably strong/veering flow with height as increasing southwesterly mid-level flow spreads eastward across the southern Plains. As a result, isolated rotating storms will likely evolve, with the greatest potential for surface-based severe risk including damaging winds likely to remain across western portions of the SLGT risk area. Into this evening, as storms continue to increase in coverage and spread eastward across central parts of the southern Plains, and perhaps initiate farther south toward the Rio Grande Valley, risk should transition to primarily hail, as convection should largely remain elevated. ..Goss/Thornton.. 02/02/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1029 AM CST Fri Feb 02 2024 Valid 021630Z - 031200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM WESTERN NORTH TEXAS AND THE BIG COUNTRY SOUTH TO THE HILL COUNTRY AND EDWARDS PLATEAU... ...SUMMARY... Local severe weather potential, mainly in the form of hail, will affect portions of the southern Plains from late afternoon into this evening. ...Synopsis... A highly amplified upper flow pattern will continue across the U.S. today. While a trough will continue crossing the eastern states and a second affects the Pacific Northwest, the primary feature with respect to convective weather will be a trough/evolving upper low advancing east-southeastward across the Desert Southwest. Ascent in advance of this feature -- and the associated left exit region of a 160 kt northwesterly upper-level jet -- will continue spreading into/across the southern Plains through the period. At the surface, a Pacific cold front -- associated with the aforementioned southwestern U.S. upper trough -- will shift out of eastern New Mexico and far West Texas into lower elevations of the southern Plains today and tonight, in tandem with an increase in thunderstorms across the region. ...Southern Plains... Morning RAOBS indicate stout capping across the southern Plains region, with expansive low clouds/stratus per visible satellite imagery due to a partially modified Gulf boundary-layer airmass streaming northwestward beneath the inversion. The low cloudiness -- and increasing convection across the area with time -- will limit potential for surface-based destabilization in most areas, particularly with eastward extent. With that said, some erosion of the low clouds is ongoing into portions of the Big Country region of Texas, with clear skies to the west -- i.e. portions of the south Plains and the Transpecos region. Resulting insolation ahead of the advancing front will likely permit eventual/afternoon thunderstorm development across the Big Country and Concho Valley region, which is then expected to spread northeastward toward western North Texas with time. Storms may also develop by this evening over the higher terrain just west of the lower Rio Grande Valley, and adjacent portions of the Edwards Plateau. Despite the somewhat cool, and only modestly moist boundary layer expected to persist across the eastern half of the southern Plains, steep lapse rates aloft will contribute to ample CAPE aloft, supporting locally vigorous updrafts. Storm intensity will be aided by favorably strong/veering flow with height as increasing southwesterly mid-level flow spreads eastward across the southern Plains. As a result, isolated rotating storms will likely evolve, with the greatest potential for surface-based severe risk including damaging winds likely to remain across western portions of the SLGT risk area. Into this evening, as storms continue to increase in coverage and spread eastward across central parts of the southern Plains, and perhaps initiate farther south toward the Rio Grande Valley, risk should transition to primarily hail, as convection should largely remain elevated. ..Goss/Thornton.. 02/02/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1029 AM CST Fri Feb 02 2024 Valid 021630Z - 031200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM WESTERN NORTH TEXAS AND THE BIG COUNTRY SOUTH TO THE HILL COUNTRY AND EDWARDS PLATEAU... ...SUMMARY... Local severe weather potential, mainly in the form of hail, will affect portions of the southern Plains from late afternoon into this evening. ...Synopsis... A highly amplified upper flow pattern will continue across the U.S. today. While a trough will continue crossing the eastern states and a second affects the Pacific Northwest, the primary feature with respect to convective weather will be a trough/evolving upper low advancing east-southeastward across the Desert Southwest. Ascent in advance of this feature -- and the associated left exit region of a 160 kt northwesterly upper-level jet -- will continue spreading into/across the southern Plains through the period. At the surface, a Pacific cold front -- associated with the aforementioned southwestern U.S. upper trough -- will shift out of eastern New Mexico and far West Texas into lower elevations of the southern Plains today and tonight, in tandem with an increase in thunderstorms across the region. ...Southern Plains... Morning RAOBS indicate stout capping across the southern Plains region, with expansive low clouds/stratus per visible satellite imagery due to a partially modified Gulf boundary-layer airmass streaming northwestward beneath the inversion. The low cloudiness -- and increasing convection across the area with time -- will limit potential for surface-based destabilization in most areas, particularly with eastward extent. With that said, some erosion of the low clouds is ongoing into portions of the Big Country region of Texas, with clear skies to the west -- i.e. portions of the south Plains and the Transpecos region. Resulting insolation ahead of the advancing front will likely permit eventual/afternoon thunderstorm development across the Big Country and Concho Valley region, which is then expected to spread northeastward toward western North Texas with time. Storms may also develop by this evening over the higher terrain just west of the lower Rio Grande Valley, and adjacent portions of the Edwards Plateau. Despite the somewhat cool, and only modestly moist boundary layer expected to persist across the eastern half of the southern Plains, steep lapse rates aloft will contribute to ample CAPE aloft, supporting locally vigorous updrafts. Storm intensity will be aided by favorably strong/veering flow with height as increasing southwesterly mid-level flow spreads eastward across the southern Plains. As a result, isolated rotating storms will likely evolve, with the greatest potential for surface-based severe risk including damaging winds likely to remain across western portions of the SLGT risk area. Into this evening, as storms continue to increase in coverage and spread eastward across central parts of the southern Plains, and perhaps initiate farther south toward the Rio Grande Valley, risk should transition to primarily hail, as convection should largely remain elevated. ..Goss/Thornton.. 02/02/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1029 AM CST Fri Feb 02 2024 Valid 021630Z - 031200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM WESTERN NORTH TEXAS AND THE BIG COUNTRY SOUTH TO THE HILL COUNTRY AND EDWARDS PLATEAU... ...SUMMARY... Local severe weather potential, mainly in the form of hail, will affect portions of the southern Plains from late afternoon into this evening. ...Synopsis... A highly amplified upper flow pattern will continue across the U.S. today. While a trough will continue crossing the eastern states and a second affects the Pacific Northwest, the primary feature with respect to convective weather will be a trough/evolving upper low advancing east-southeastward across the Desert Southwest. Ascent in advance of this feature -- and the associated left exit region of a 160 kt northwesterly upper-level jet -- will continue spreading into/across the southern Plains through the period. At the surface, a Pacific cold front -- associated with the aforementioned southwestern U.S. upper trough -- will shift out of eastern New Mexico and far West Texas into lower elevations of the southern Plains today and tonight, in tandem with an increase in thunderstorms across the region. ...Southern Plains... Morning RAOBS indicate stout capping across the southern Plains region, with expansive low clouds/stratus per visible satellite imagery due to a partially modified Gulf boundary-layer airmass streaming northwestward beneath the inversion. The low cloudiness -- and increasing convection across the area with time -- will limit potential for surface-based destabilization in most areas, particularly with eastward extent. With that said, some erosion of the low clouds is ongoing into portions of the Big Country region of Texas, with clear skies to the west -- i.e. portions of the south Plains and the Transpecos region. Resulting insolation ahead of the advancing front will likely permit eventual/afternoon thunderstorm development across the Big Country and Concho Valley region, which is then expected to spread northeastward toward western North Texas with time. Storms may also develop by this evening over the higher terrain just west of the lower Rio Grande Valley, and adjacent portions of the Edwards Plateau. Despite the somewhat cool, and only modestly moist boundary layer expected to persist across the eastern half of the southern Plains, steep lapse rates aloft will contribute to ample CAPE aloft, supporting locally vigorous updrafts. Storm intensity will be aided by favorably strong/veering flow with height as increasing southwesterly mid-level flow spreads eastward across the southern Plains. As a result, isolated rotating storms will likely evolve, with the greatest potential for surface-based severe risk including damaging winds likely to remain across western portions of the SLGT risk area. Into this evening, as storms continue to increase in coverage and spread eastward across central parts of the southern Plains, and perhaps initiate farther south toward the Rio Grande Valley, risk should transition to primarily hail, as convection should largely remain elevated. ..Goss/Thornton.. 02/02/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1029 AM CST Fri Feb 02 2024 Valid 021630Z - 031200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM WESTERN NORTH TEXAS AND THE BIG COUNTRY SOUTH TO THE HILL COUNTRY AND EDWARDS PLATEAU... ...SUMMARY... Local severe weather potential, mainly in the form of hail, will affect portions of the southern Plains from late afternoon into this evening. ...Synopsis... A highly amplified upper flow pattern will continue across the U.S. today. While a trough will continue crossing the eastern states and a second affects the Pacific Northwest, the primary feature with respect to convective weather will be a trough/evolving upper low advancing east-southeastward across the Desert Southwest. Ascent in advance of this feature -- and the associated left exit region of a 160 kt northwesterly upper-level jet -- will continue spreading into/across the southern Plains through the period. At the surface, a Pacific cold front -- associated with the aforementioned southwestern U.S. upper trough -- will shift out of eastern New Mexico and far West Texas into lower elevations of the southern Plains today and tonight, in tandem with an increase in thunderstorms across the region. ...Southern Plains... Morning RAOBS indicate stout capping across the southern Plains region, with expansive low clouds/stratus per visible satellite imagery due to a partially modified Gulf boundary-layer airmass streaming northwestward beneath the inversion. The low cloudiness -- and increasing convection across the area with time -- will limit potential for surface-based destabilization in most areas, particularly with eastward extent. With that said, some erosion of the low clouds is ongoing into portions of the Big Country region of Texas, with clear skies to the west -- i.e. portions of the south Plains and the Transpecos region. Resulting insolation ahead of the advancing front will likely permit eventual/afternoon thunderstorm development across the Big Country and Concho Valley region, which is then expected to spread northeastward toward western North Texas with time. Storms may also develop by this evening over the higher terrain just west of the lower Rio Grande Valley, and adjacent portions of the Edwards Plateau. Despite the somewhat cool, and only modestly moist boundary layer expected to persist across the eastern half of the southern Plains, steep lapse rates aloft will contribute to ample CAPE aloft, supporting locally vigorous updrafts. Storm intensity will be aided by favorably strong/veering flow with height as increasing southwesterly mid-level flow spreads eastward across the southern Plains. As a result, isolated rotating storms will likely evolve, with the greatest potential for surface-based severe risk including damaging winds likely to remain across western portions of the SLGT risk area. Into this evening, as storms continue to increase in coverage and spread eastward across central parts of the southern Plains, and perhaps initiate farther south toward the Rio Grande Valley, risk should transition to primarily hail, as convection should largely remain elevated. ..Goss/Thornton.. 02/02/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1029 AM CST Fri Feb 02 2024 Valid 021630Z - 031200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM WESTERN NORTH TEXAS AND THE BIG COUNTRY SOUTH TO THE HILL COUNTRY AND EDWARDS PLATEAU... ...SUMMARY... Local severe weather potential, mainly in the form of hail, will affect portions of the southern Plains from late afternoon into this evening. ...Synopsis... A highly amplified upper flow pattern will continue across the U.S. today. While a trough will continue crossing the eastern states and a second affects the Pacific Northwest, the primary feature with respect to convective weather will be a trough/evolving upper low advancing east-southeastward across the Desert Southwest. Ascent in advance of this feature -- and the associated left exit region of a 160 kt northwesterly upper-level jet -- will continue spreading into/across the southern Plains through the period. At the surface, a Pacific cold front -- associated with the aforementioned southwestern U.S. upper trough -- will shift out of eastern New Mexico and far West Texas into lower elevations of the southern Plains today and tonight, in tandem with an increase in thunderstorms across the region. ...Southern Plains... Morning RAOBS indicate stout capping across the southern Plains region, with expansive low clouds/stratus per visible satellite imagery due to a partially modified Gulf boundary-layer airmass streaming northwestward beneath the inversion. The low cloudiness -- and increasing convection across the area with time -- will limit potential for surface-based destabilization in most areas, particularly with eastward extent. With that said, some erosion of the low clouds is ongoing into portions of the Big Country region of Texas, with clear skies to the west -- i.e. portions of the south Plains and the Transpecos region. Resulting insolation ahead of the advancing front will likely permit eventual/afternoon thunderstorm development across the Big Country and Concho Valley region, which is then expected to spread northeastward toward western North Texas with time. Storms may also develop by this evening over the higher terrain just west of the lower Rio Grande Valley, and adjacent portions of the Edwards Plateau. Despite the somewhat cool, and only modestly moist boundary layer expected to persist across the eastern half of the southern Plains, steep lapse rates aloft will contribute to ample CAPE aloft, supporting locally vigorous updrafts. Storm intensity will be aided by favorably strong/veering flow with height as increasing southwesterly mid-level flow spreads eastward across the southern Plains. As a result, isolated rotating storms will likely evolve, with the greatest potential for surface-based severe risk including damaging winds likely to remain across western portions of the SLGT risk area. Into this evening, as storms continue to increase in coverage and spread eastward across central parts of the southern Plains, and perhaps initiate farther south toward the Rio Grande Valley, risk should transition to primarily hail, as convection should largely remain elevated. ..Goss/Thornton.. 02/02/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0653 AM CST Fri Feb 02 2024 Valid 021300Z - 031200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PARTS OF NORTHWEST TEXAS TO PARTS OF SOUTH-CENTRAL TEXAS AND THE NEARBY RIO GRANDE VALLEY... ...SUMMARY... Severe hail, damaging gusts and a tornado or two are possible over parts of the southern Plains, from late afternoon into this evening. ...Synopsis... A highly amplified, somewhat progressive mid/upper-level pattern is forecast through the period, with ridging shifting slowly eastward across central Canada and the Mississippi Valley. Upstream, height falls will spread across the Rockies and Great Plains States. The most convectively impactful feature will be a basal shortwave trough -- with several associated vorticity maxima -- initially evident in moisture-channel imagery over portions of southern CA, the lower Colorado River Valley, and northwestern MX. The trough should shift eastward and strengthen, extending from the Four Corners area across central/southern NM past ELP and over Chihuahua around 00Z. By 12Z, a closed 500-mb low should develop over northeastern NM, with the trough south-southeastward across the Llano Estacado and Permian Basin to Coahuila. At 11Z, surface analysis showed lee troughing over eastern parts of CO and NM, with a few weak/attached lows, as well as pockets of 60s F surface dewpoints reaching as far north as the SAT-AUS region. A diffuse Pacific cold front was apparent over east-central NM and far west TX, and should sharpen through the day as it crosses west TX. A dryline was drawn from northwest TX southwestward over the Permian Basin, then south-southeastward into higher terrain of northern Coahuila. This dryline should mix eastward through this afternoon to the Edwards Plateau on the south side, and move little on the north side. The lee trough should strengthen throughout the period, with cyclogenesis expected overnight in the area from the northwestern TX Panhandle to southeastern CO. The Pacific front to its south and southeast should overtake the dryline and shift eastward from west TX into central and south TX tonight. ...TX/OK... Episodes of strong-severe thunderstorms are expected to cross the outlook area starting this afternoon along/ahead of the dryline -- initially moving roughly northward over in the northwest TX/eastern Panhandle/western OK region. Isolated severe hail, damaging gusts and potential for a brief tornado exists with this activity. A later but more-substantial severe threat is apparent across parts of northwest, central and southwest TX, east of late-afternoon/early-evening development areas along: 1. The dryline, 2. The Pacific front, and 3. Eastern slopes of the Serranias del Burro of Coahuila leading down to the Rio Grande. Supercellular and bowing/quasi-linear modes are possible in and near the "slight" area, offering sporadic severe hail, isolated severe gusts and potential for a tornado or two. Some hail may exceed 2 inches in diameter from supercell(s) in the first few hours of the convective cycle over parts of south TX (southern Hill Country southward). In that area, the most-favorable combination of steep deep-layer lapse rates, inflow-layer moisture, and long hodographs is expected. Large-scale lift will strengthen through tonight across much of the southern Plains -- under the influences of low-level warm advection and midlevel DCVA. Also, as a 125-160-kt 250-mb jet extends inland across southern CA and northwestern MX -- behind the mid/upper trough -- its left-exit region and associated lift aloft should spread this evening and overnight across parts of central/south TX, where the steepest midlevel lapse rates (exceeding 7 deg C/km) are expected. These influences will extend atop a moistening and diurnally destabilizing boundary layer with surface dewpoints in the 50s F over northwest TX and OK, and 60s in the Edwards Plateau and Hill Country southward to the Rio Grande. Adequate deep-layer instability/buoyancy for surface-based convection is expected on either side of the dryline today, and along/ahead of the Pacific front tonight. Peak/preconvective MLCAPE should reach around 1000-1500 J/kg in a narrow, south-north corridor ahead of the dryline, diminishing eastward toward east TX. Low-level shear may be stronger over northern parts of the outlook, but with greater deep shear southward toward the more-intense mid/upper winds. ..Edwards/Leitman.. 02/02/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0653 AM CST Fri Feb 02 2024 Valid 021300Z - 031200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PARTS OF NORTHWEST TEXAS TO PARTS OF SOUTH-CENTRAL TEXAS AND THE NEARBY RIO GRANDE VALLEY... ...SUMMARY... Severe hail, damaging gusts and a tornado or two are possible over parts of the southern Plains, from late afternoon into this evening. ...Synopsis... A highly amplified, somewhat progressive mid/upper-level pattern is forecast through the period, with ridging shifting slowly eastward across central Canada and the Mississippi Valley. Upstream, height falls will spread across the Rockies and Great Plains States. The most convectively impactful feature will be a basal shortwave trough -- with several associated vorticity maxima -- initially evident in moisture-channel imagery over portions of southern CA, the lower Colorado River Valley, and northwestern MX. The trough should shift eastward and strengthen, extending from the Four Corners area across central/southern NM past ELP and over Chihuahua around 00Z. By 12Z, a closed 500-mb low should develop over northeastern NM, with the trough south-southeastward across the Llano Estacado and Permian Basin to Coahuila. At 11Z, surface analysis showed lee troughing over eastern parts of CO and NM, with a few weak/attached lows, as well as pockets of 60s F surface dewpoints reaching as far north as the SAT-AUS region. A diffuse Pacific cold front was apparent over east-central NM and far west TX, and should sharpen through the day as it crosses west TX. A dryline was drawn from northwest TX southwestward over the Permian Basin, then south-southeastward into higher terrain of northern Coahuila. This dryline should mix eastward through this afternoon to the Edwards Plateau on the south side, and move little on the north side. The lee trough should strengthen throughout the period, with cyclogenesis expected overnight in the area from the northwestern TX Panhandle to southeastern CO. The Pacific front to its south and southeast should overtake the dryline and shift eastward from west TX into central and south TX tonight. ...TX/OK... Episodes of strong-severe thunderstorms are expected to cross the outlook area starting this afternoon along/ahead of the dryline -- initially moving roughly northward over in the northwest TX/eastern Panhandle/western OK region. Isolated severe hail, damaging gusts and potential for a brief tornado exists with this activity. A later but more-substantial severe threat is apparent across parts of northwest, central and southwest TX, east of late-afternoon/early-evening development areas along: 1. The dryline, 2. The Pacific front, and 3. Eastern slopes of the Serranias del Burro of Coahuila leading down to the Rio Grande. Supercellular and bowing/quasi-linear modes are possible in and near the "slight" area, offering sporadic severe hail, isolated severe gusts and potential for a tornado or two. Some hail may exceed 2 inches in diameter from supercell(s) in the first few hours of the convective cycle over parts of south TX (southern Hill Country southward). In that area, the most-favorable combination of steep deep-layer lapse rates, inflow-layer moisture, and long hodographs is expected. Large-scale lift will strengthen through tonight across much of the southern Plains -- under the influences of low-level warm advection and midlevel DCVA. Also, as a 125-160-kt 250-mb jet extends inland across southern CA and northwestern MX -- behind the mid/upper trough -- its left-exit region and associated lift aloft should spread this evening and overnight across parts of central/south TX, where the steepest midlevel lapse rates (exceeding 7 deg C/km) are expected. These influences will extend atop a moistening and diurnally destabilizing boundary layer with surface dewpoints in the 50s F over northwest TX and OK, and 60s in the Edwards Plateau and Hill Country southward to the Rio Grande. Adequate deep-layer instability/buoyancy for surface-based convection is expected on either side of the dryline today, and along/ahead of the Pacific front tonight. Peak/preconvective MLCAPE should reach around 1000-1500 J/kg in a narrow, south-north corridor ahead of the dryline, diminishing eastward toward east TX. Low-level shear may be stronger over northern parts of the outlook, but with greater deep shear southward toward the more-intense mid/upper winds. ..Edwards/Leitman.. 02/02/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0653 AM CST Fri Feb 02 2024 Valid 021300Z - 031200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PARTS OF NORTHWEST TEXAS TO PARTS OF SOUTH-CENTRAL TEXAS AND THE NEARBY RIO GRANDE VALLEY... ...SUMMARY... Severe hail, damaging gusts and a tornado or two are possible over parts of the southern Plains, from late afternoon into this evening. ...Synopsis... A highly amplified, somewhat progressive mid/upper-level pattern is forecast through the period, with ridging shifting slowly eastward across central Canada and the Mississippi Valley. Upstream, height falls will spread across the Rockies and Great Plains States. The most convectively impactful feature will be a basal shortwave trough -- with several associated vorticity maxima -- initially evident in moisture-channel imagery over portions of southern CA, the lower Colorado River Valley, and northwestern MX. The trough should shift eastward and strengthen, extending from the Four Corners area across central/southern NM past ELP and over Chihuahua around 00Z. By 12Z, a closed 500-mb low should develop over northeastern NM, with the trough south-southeastward across the Llano Estacado and Permian Basin to Coahuila. At 11Z, surface analysis showed lee troughing over eastern parts of CO and NM, with a few weak/attached lows, as well as pockets of 60s F surface dewpoints reaching as far north as the SAT-AUS region. A diffuse Pacific cold front was apparent over east-central NM and far west TX, and should sharpen through the day as it crosses west TX. A dryline was drawn from northwest TX southwestward over the Permian Basin, then south-southeastward into higher terrain of northern Coahuila. This dryline should mix eastward through this afternoon to the Edwards Plateau on the south side, and move little on the north side. The lee trough should strengthen throughout the period, with cyclogenesis expected overnight in the area from the northwestern TX Panhandle to southeastern CO. The Pacific front to its south and southeast should overtake the dryline and shift eastward from west TX into central and south TX tonight. ...TX/OK... Episodes of strong-severe thunderstorms are expected to cross the outlook area starting this afternoon along/ahead of the dryline -- initially moving roughly northward over in the northwest TX/eastern Panhandle/western OK region. Isolated severe hail, damaging gusts and potential for a brief tornado exists with this activity. A later but more-substantial severe threat is apparent across parts of northwest, central and southwest TX, east of late-afternoon/early-evening development areas along: 1. The dryline, 2. The Pacific front, and 3. Eastern slopes of the Serranias del Burro of Coahuila leading down to the Rio Grande. Supercellular and bowing/quasi-linear modes are possible in and near the "slight" area, offering sporadic severe hail, isolated severe gusts and potential for a tornado or two. Some hail may exceed 2 inches in diameter from supercell(s) in the first few hours of the convective cycle over parts of south TX (southern Hill Country southward). In that area, the most-favorable combination of steep deep-layer lapse rates, inflow-layer moisture, and long hodographs is expected. Large-scale lift will strengthen through tonight across much of the southern Plains -- under the influences of low-level warm advection and midlevel DCVA. Also, as a 125-160-kt 250-mb jet extends inland across southern CA and northwestern MX -- behind the mid/upper trough -- its left-exit region and associated lift aloft should spread this evening and overnight across parts of central/south TX, where the steepest midlevel lapse rates (exceeding 7 deg C/km) are expected. These influences will extend atop a moistening and diurnally destabilizing boundary layer with surface dewpoints in the 50s F over northwest TX and OK, and 60s in the Edwards Plateau and Hill Country southward to the Rio Grande. Adequate deep-layer instability/buoyancy for surface-based convection is expected on either side of the dryline today, and along/ahead of the Pacific front tonight. Peak/preconvective MLCAPE should reach around 1000-1500 J/kg in a narrow, south-north corridor ahead of the dryline, diminishing eastward toward east TX. Low-level shear may be stronger over northern parts of the outlook, but with greater deep shear southward toward the more-intense mid/upper winds. ..Edwards/Leitman.. 02/02/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0653 AM CST Fri Feb 02 2024 Valid 021300Z - 031200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PARTS OF NORTHWEST TEXAS TO PARTS OF SOUTH-CENTRAL TEXAS AND THE NEARBY RIO GRANDE VALLEY... ...SUMMARY... Severe hail, damaging gusts and a tornado or two are possible over parts of the southern Plains, from late afternoon into this evening. ...Synopsis... A highly amplified, somewhat progressive mid/upper-level pattern is forecast through the period, with ridging shifting slowly eastward across central Canada and the Mississippi Valley. Upstream, height falls will spread across the Rockies and Great Plains States. The most convectively impactful feature will be a basal shortwave trough -- with several associated vorticity maxima -- initially evident in moisture-channel imagery over portions of southern CA, the lower Colorado River Valley, and northwestern MX. The trough should shift eastward and strengthen, extending from the Four Corners area across central/southern NM past ELP and over Chihuahua around 00Z. By 12Z, a closed 500-mb low should develop over northeastern NM, with the trough south-southeastward across the Llano Estacado and Permian Basin to Coahuila. At 11Z, surface analysis showed lee troughing over eastern parts of CO and NM, with a few weak/attached lows, as well as pockets of 60s F surface dewpoints reaching as far north as the SAT-AUS region. A diffuse Pacific cold front was apparent over east-central NM and far west TX, and should sharpen through the day as it crosses west TX. A dryline was drawn from northwest TX southwestward over the Permian Basin, then south-southeastward into higher terrain of northern Coahuila. This dryline should mix eastward through this afternoon to the Edwards Plateau on the south side, and move little on the north side. The lee trough should strengthen throughout the period, with cyclogenesis expected overnight in the area from the northwestern TX Panhandle to southeastern CO. The Pacific front to its south and southeast should overtake the dryline and shift eastward from west TX into central and south TX tonight. ...TX/OK... Episodes of strong-severe thunderstorms are expected to cross the outlook area starting this afternoon along/ahead of the dryline -- initially moving roughly northward over in the northwest TX/eastern Panhandle/western OK region. Isolated severe hail, damaging gusts and potential for a brief tornado exists with this activity. A later but more-substantial severe threat is apparent across parts of northwest, central and southwest TX, east of late-afternoon/early-evening development areas along: 1. The dryline, 2. The Pacific front, and 3. Eastern slopes of the Serranias del Burro of Coahuila leading down to the Rio Grande. Supercellular and bowing/quasi-linear modes are possible in and near the "slight" area, offering sporadic severe hail, isolated severe gusts and potential for a tornado or two. Some hail may exceed 2 inches in diameter from supercell(s) in the first few hours of the convective cycle over parts of south TX (southern Hill Country southward). In that area, the most-favorable combination of steep deep-layer lapse rates, inflow-layer moisture, and long hodographs is expected. Large-scale lift will strengthen through tonight across much of the southern Plains -- under the influences of low-level warm advection and midlevel DCVA. Also, as a 125-160-kt 250-mb jet extends inland across southern CA and northwestern MX -- behind the mid/upper trough -- its left-exit region and associated lift aloft should spread this evening and overnight across parts of central/south TX, where the steepest midlevel lapse rates (exceeding 7 deg C/km) are expected. These influences will extend atop a moistening and diurnally destabilizing boundary layer with surface dewpoints in the 50s F over northwest TX and OK, and 60s in the Edwards Plateau and Hill Country southward to the Rio Grande. Adequate deep-layer instability/buoyancy for surface-based convection is expected on either side of the dryline today, and along/ahead of the Pacific front tonight. Peak/preconvective MLCAPE should reach around 1000-1500 J/kg in a narrow, south-north corridor ahead of the dryline, diminishing eastward toward east TX. Low-level shear may be stronger over northern parts of the outlook, but with greater deep shear southward toward the more-intense mid/upper winds. ..Edwards/Leitman.. 02/02/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0653 AM CST Fri Feb 02 2024 Valid 021300Z - 031200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PARTS OF NORTHWEST TEXAS TO PARTS OF SOUTH-CENTRAL TEXAS AND THE NEARBY RIO GRANDE VALLEY... ...SUMMARY... Severe hail, damaging gusts and a tornado or two are possible over parts of the southern Plains, from late afternoon into this evening. ...Synopsis... A highly amplified, somewhat progressive mid/upper-level pattern is forecast through the period, with ridging shifting slowly eastward across central Canada and the Mississippi Valley. Upstream, height falls will spread across the Rockies and Great Plains States. The most convectively impactful feature will be a basal shortwave trough -- with several associated vorticity maxima -- initially evident in moisture-channel imagery over portions of southern CA, the lower Colorado River Valley, and northwestern MX. The trough should shift eastward and strengthen, extending from the Four Corners area across central/southern NM past ELP and over Chihuahua around 00Z. By 12Z, a closed 500-mb low should develop over northeastern NM, with the trough south-southeastward across the Llano Estacado and Permian Basin to Coahuila. At 11Z, surface analysis showed lee troughing over eastern parts of CO and NM, with a few weak/attached lows, as well as pockets of 60s F surface dewpoints reaching as far north as the SAT-AUS region. A diffuse Pacific cold front was apparent over east-central NM and far west TX, and should sharpen through the day as it crosses west TX. A dryline was drawn from northwest TX southwestward over the Permian Basin, then south-southeastward into higher terrain of northern Coahuila. This dryline should mix eastward through this afternoon to the Edwards Plateau on the south side, and move little on the north side. The lee trough should strengthen throughout the period, with cyclogenesis expected overnight in the area from the northwestern TX Panhandle to southeastern CO. The Pacific front to its south and southeast should overtake the dryline and shift eastward from west TX into central and south TX tonight. ...TX/OK... Episodes of strong-severe thunderstorms are expected to cross the outlook area starting this afternoon along/ahead of the dryline -- initially moving roughly northward over in the northwest TX/eastern Panhandle/western OK region. Isolated severe hail, damaging gusts and potential for a brief tornado exists with this activity. A later but more-substantial severe threat is apparent across parts of northwest, central and southwest TX, east of late-afternoon/early-evening development areas along: 1. The dryline, 2. The Pacific front, and 3. Eastern slopes of the Serranias del Burro of Coahuila leading down to the Rio Grande. Supercellular and bowing/quasi-linear modes are possible in and near the "slight" area, offering sporadic severe hail, isolated severe gusts and potential for a tornado or two. Some hail may exceed 2 inches in diameter from supercell(s) in the first few hours of the convective cycle over parts of south TX (southern Hill Country southward). In that area, the most-favorable combination of steep deep-layer lapse rates, inflow-layer moisture, and long hodographs is expected. Large-scale lift will strengthen through tonight across much of the southern Plains -- under the influences of low-level warm advection and midlevel DCVA. Also, as a 125-160-kt 250-mb jet extends inland across southern CA and northwestern MX -- behind the mid/upper trough -- its left-exit region and associated lift aloft should spread this evening and overnight across parts of central/south TX, where the steepest midlevel lapse rates (exceeding 7 deg C/km) are expected. These influences will extend atop a moistening and diurnally destabilizing boundary layer with surface dewpoints in the 50s F over northwest TX and OK, and 60s in the Edwards Plateau and Hill Country southward to the Rio Grande. Adequate deep-layer instability/buoyancy for surface-based convection is expected on either side of the dryline today, and along/ahead of the Pacific front tonight. Peak/preconvective MLCAPE should reach around 1000-1500 J/kg in a narrow, south-north corridor ahead of the dryline, diminishing eastward toward east TX. Low-level shear may be stronger over northern parts of the outlook, but with greater deep shear southward toward the more-intense mid/upper winds. ..Edwards/Leitman.. 02/02/2024 Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0353 AM CST Fri Feb 02 2024 Valid 051200Z - 101200Z ...DISCUSSION... In the wake of severe threats today through Sunday, a return to negligible severe potential is anticipated for much of next week. Northerly low-level flow over the Gulf through midweek will mitigate thunderstorm development across all but southern CA on D5-6. The latter will be supported by a slow-moving, amplified upper trough approaching southern CA and Baja CA. Guidance has above-average agreement regarding the progression of this trough across the West into the Great Plains towards the end of the period. As this occurs, modifying low-level return flow from the western Gulf will ensue beneath an elevated mixed layer. Despite this, instability progs appear rather weak where cyclogenesis focuses from the central High Plains to Upper Midwest. Given a likely positive-tilt orientation of the trough, in conjunction with a slowly southeastward-moving cold front that is oriented nearly parallel to the deep-layer flow, the setup does not appear to support an organized severe threat. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0353 AM CST Fri Feb 02 2024 Valid 051200Z - 101200Z ...DISCUSSION... In the wake of severe threats today through Sunday, a return to negligible severe potential is anticipated for much of next week. Northerly low-level flow over the Gulf through midweek will mitigate thunderstorm development across all but southern CA on D5-6. The latter will be supported by a slow-moving, amplified upper trough approaching southern CA and Baja CA. Guidance has above-average agreement regarding the progression of this trough across the West into the Great Plains towards the end of the period. As this occurs, modifying low-level return flow from the western Gulf will ensue beneath an elevated mixed layer. Despite this, instability progs appear rather weak where cyclogenesis focuses from the central High Plains to Upper Midwest. Given a likely positive-tilt orientation of the trough, in conjunction with a slowly southeastward-moving cold front that is oriented nearly parallel to the deep-layer flow, the setup does not appear to support an organized severe threat. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0353 AM CST Fri Feb 02 2024 Valid 051200Z - 101200Z ...DISCUSSION... In the wake of severe threats today through Sunday, a return to negligible severe potential is anticipated for much of next week. Northerly low-level flow over the Gulf through midweek will mitigate thunderstorm development across all but southern CA on D5-6. The latter will be supported by a slow-moving, amplified upper trough approaching southern CA and Baja CA. Guidance has above-average agreement regarding the progression of this trough across the West into the Great Plains towards the end of the period. As this occurs, modifying low-level return flow from the western Gulf will ensue beneath an elevated mixed layer. Despite this, instability progs appear rather weak where cyclogenesis focuses from the central High Plains to Upper Midwest. Given a likely positive-tilt orientation of the trough, in conjunction with a slowly southeastward-moving cold front that is oriented nearly parallel to the deep-layer flow, the setup does not appear to support an organized severe threat. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0353 AM CST Fri Feb 02 2024 Valid 051200Z - 101200Z ...DISCUSSION... In the wake of severe threats today through Sunday, a return to negligible severe potential is anticipated for much of next week. Northerly low-level flow over the Gulf through midweek will mitigate thunderstorm development across all but southern CA on D5-6. The latter will be supported by a slow-moving, amplified upper trough approaching southern CA and Baja CA. Guidance has above-average agreement regarding the progression of this trough across the West into the Great Plains towards the end of the period. As this occurs, modifying low-level return flow from the western Gulf will ensue beneath an elevated mixed layer. Despite this, instability progs appear rather weak where cyclogenesis focuses from the central High Plains to Upper Midwest. Given a likely positive-tilt orientation of the trough, in conjunction with a slowly southeastward-moving cold front that is oriented nearly parallel to the deep-layer flow, the setup does not appear to support an organized severe threat. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0353 AM CST Fri Feb 02 2024 Valid 051200Z - 101200Z ...DISCUSSION... In the wake of severe threats today through Sunday, a return to negligible severe potential is anticipated for much of next week. Northerly low-level flow over the Gulf through midweek will mitigate thunderstorm development across all but southern CA on D5-6. The latter will be supported by a slow-moving, amplified upper trough approaching southern CA and Baja CA. Guidance has above-average agreement regarding the progression of this trough across the West into the Great Plains towards the end of the period. As this occurs, modifying low-level return flow from the western Gulf will ensue beneath an elevated mixed layer. Despite this, instability progs appear rather weak where cyclogenesis focuses from the central High Plains to Upper Midwest. Given a likely positive-tilt orientation of the trough, in conjunction with a slowly southeastward-moving cold front that is oriented nearly parallel to the deep-layer flow, the setup does not appear to support an organized severe threat. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0353 AM CST Fri Feb 02 2024 Valid 051200Z - 101200Z ...DISCUSSION... In the wake of severe threats today through Sunday, a return to negligible severe potential is anticipated for much of next week. Northerly low-level flow over the Gulf through midweek will mitigate thunderstorm development across all but southern CA on D5-6. The latter will be supported by a slow-moving, amplified upper trough approaching southern CA and Baja CA. Guidance has above-average agreement regarding the progression of this trough across the West into the Great Plains towards the end of the period. As this occurs, modifying low-level return flow from the western Gulf will ensue beneath an elevated mixed layer. Despite this, instability progs appear rather weak where cyclogenesis focuses from the central High Plains to Upper Midwest. Given a likely positive-tilt orientation of the trough, in conjunction with a slowly southeastward-moving cold front that is oriented nearly parallel to the deep-layer flow, the setup does not appear to support an organized severe threat. Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 AM CST Fri Feb 02 2024 Valid 041200Z - 051200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN SOUTH TO CENTRAL FL... ...SUMMARY... Isolated severe thunderstorms are possible across south to central Florida late morning to afternoon Sunday. ...South to central FL... Secondary cyclogenesis remains the consensus forecast in the north-central Gulf to FL Panhandle vicinity, during the latter portion D2 into the first half of D3. This process should occur as the intense mid-level jet, centered on the Rio Grande Valley/south TX into the northwest Gulf at 12Z Sunday, translates eastward across the Gulf into the south FL Peninsula by early Monday. A conditional high-shear/low-CAPE setup remains plausible across the southern half of the peninsula during the late morning to afternoon. The 00Z NAM is clearly on the aggressive spectrum of guidance with the amplification of low to mid-level flow across south FL, yielding rather enlarged hodographs coupled with adequate surface-based instability advecting northeast from the eastern Gulf. Guidance consensus is for a more subdued intrusion of eastern Gulf moisture, likely occurring on the backside of scattered morning to afternoon convection that spreads towards the peninsula within a more moderate low-level warm conveyor. Given the spread across guidance and in run-to-run continuity, have deferred to later outlooks for potential delineation of a cat 2-SLGT risk. ...Coastal central CA... Within the left-exit of an intense upper jet over the eastern Pacific, an approaching shortwave trough will aid in cyclogenesis late D2 into early D3 off the CA coast. Guidance has pronounced spread with the amplitude of this cyclogenesis, as well as run-to-run continuity differences in how close to the coast it occurs. The more aggressive guidance suggests a conditional brief tornado threat might develop around the afternoon to early evening, if adequate surface-based instability can spread towards the coast. But with below-average forecast confidence given the guidance uncertainty, will defer to later outlooks for the possibility of a cat 1-MRGL risk. ..Grams.. 02/02/2024 Read more