Severe Storms

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0258 PM CDT Sat May 04 2024 Valid 042000Z - 051200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR WEST TEXAS... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF NORTHWEST/WEST-CENTRAL ILLINOIS... ...SUMMARY... Scattered severe thunderstorms are expected across parts of the southern High Plains into the Hill Country of central Texas this afternoon and evening. Several storms may produce very large hail, and a couple strong tornadoes are possible. ...20Z Update... ...Far West Texas into TX Hill Country/Central TX... Outflow-augmented cold front continues to surge southward across the Permian Basin. Development along the front has been relatively short-lived thus far, primarily due to the undercutting of the updrafts. Even so, buoyancy is building north of the front, so more storm maturation and increasing severe potential appears possible north of the front. A more thermodynamically favorable environment exists south of the surging cold front, where there is a greater potential for surface-based storms capable of all severe hazards, including tornadoes. This initially more discrete activity will likely increase in coverage later this evening as the shortwave trough currently moving through northern Mexico reaches Far West Texas. Some potential for upscale growth exists as forcing increasing, with the resulting MCS then pushing eastward through the Hill Country. Damaging wind gusts will be the primary hazards with this convective line. However, ample low-level moisture and veering low-level flow could support a few line-embedded QLCS tornadoes. ...Western Illinois... As mentioned in recently issued MCD #630, the airmass ahead of the southeastward-progressing cold front will continue to destabilize as dewpoints climb into the mid-60s and temperatures warm into the low 80s. Substantial instability (~1500-2000 J/kg MLCAPE) and modest deep-layer shear will lead to some loosely organized multicell thunderstorms capable of isolated hail and damaging gusts along and ahead of the front later this afternoon. ..Mosier.. 05/04/2024 .PREV DISCUSSION... /ISSUED 1142 AM CDT Sat May 04 2024/ ...TX/southern OK/extreme southeastern NM... Not much change for this outlook update other than a minor southward shift of severe probabilities across far southeast NM and West TX to account for the projected cold front position by mid afternoon. Still expecting widely scattered to scattered thunderstorms to form this afternoon along and behind the cold front over west TX and southeastern NM, as well as ahead of the cold front, near the dryline and over strongly heated, relatively high elevations west of the Pecos Valley. The stronger updrafts will attain supercell characteristics and pose a large-hail threat on both sides of the front, with severe-wind and tornado potential more prevalent to its south. Forecast soundings south of the front indicate veering and increasing flow with height which will become very favorable for supercells. It still appears one or two dominant, prefrontal, mid/late-afternoon supercells may evolve and remain south of the front. The potential for a strong tornado in addition to giant hail will be the primary hazards with these warm sector supercells. Additional storm development is expected by early evening with an amassing of cold pools eventually expected, as southeasterly 850mb flow strengthens. A severe MCS will likely evolve during the evening and probably persist into the overnight as it moves east across portions of the Edwards Plateau and central TX. Have expanded wind probabilities farther east to account for a lingering threat for severe gusts and perhaps a localized risk for a tornado late as this activity moves east of I-35. ...North/northeast TX to mid Mississippi Valley/western Great Lakes vicinity... A diurnal intensification of isolated to scattered thunderstorms is expected this afternoon within this general corridor from the Red River Valley northeastward into the IL/WI vicinity. With much of this region located in between larger-scale mid-level waves, modest kinematic fields will tend to limit overall storm organization and severe potential. Nonetheless, heating of a moist boundary layer will facilitate the development of moderate instability by early to mid afternoon. Mainly semi-organized bands of multicells and clusters thereof will occasionally result in sporadic potential for wind damage and large hail. It appears perhaps a corridor for greater wind damage potential may occur immediately ahead/downstream of an MCV moving east across the mid MS Valley. Model guidance indicates slightly greater organized line segments and wind potential later this afternoon from central into northern portions of IL. Have also expanded the MRGL northward into portions of WI where sufficient destabilization will occur ahead of a front and associated mid-level disturbance over the Upper Midwest. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0258 PM CDT Sat May 04 2024 Valid 042000Z - 051200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR WEST TEXAS... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF NORTHWEST/WEST-CENTRAL ILLINOIS... ...SUMMARY... Scattered severe thunderstorms are expected across parts of the southern High Plains into the Hill Country of central Texas this afternoon and evening. Several storms may produce very large hail, and a couple strong tornadoes are possible. ...20Z Update... ...Far West Texas into TX Hill Country/Central TX... Outflow-augmented cold front continues to surge southward across the Permian Basin. Development along the front has been relatively short-lived thus far, primarily due to the undercutting of the updrafts. Even so, buoyancy is building north of the front, so more storm maturation and increasing severe potential appears possible north of the front. A more thermodynamically favorable environment exists south of the surging cold front, where there is a greater potential for surface-based storms capable of all severe hazards, including tornadoes. This initially more discrete activity will likely increase in coverage later this evening as the shortwave trough currently moving through northern Mexico reaches Far West Texas. Some potential for upscale growth exists as forcing increasing, with the resulting MCS then pushing eastward through the Hill Country. Damaging wind gusts will be the primary hazards with this convective line. However, ample low-level moisture and veering low-level flow could support a few line-embedded QLCS tornadoes. ...Western Illinois... As mentioned in recently issued MCD #630, the airmass ahead of the southeastward-progressing cold front will continue to destabilize as dewpoints climb into the mid-60s and temperatures warm into the low 80s. Substantial instability (~1500-2000 J/kg MLCAPE) and modest deep-layer shear will lead to some loosely organized multicell thunderstorms capable of isolated hail and damaging gusts along and ahead of the front later this afternoon. ..Mosier.. 05/04/2024 .PREV DISCUSSION... /ISSUED 1142 AM CDT Sat May 04 2024/ ...TX/southern OK/extreme southeastern NM... Not much change for this outlook update other than a minor southward shift of severe probabilities across far southeast NM and West TX to account for the projected cold front position by mid afternoon. Still expecting widely scattered to scattered thunderstorms to form this afternoon along and behind the cold front over west TX and southeastern NM, as well as ahead of the cold front, near the dryline and over strongly heated, relatively high elevations west of the Pecos Valley. The stronger updrafts will attain supercell characteristics and pose a large-hail threat on both sides of the front, with severe-wind and tornado potential more prevalent to its south. Forecast soundings south of the front indicate veering and increasing flow with height which will become very favorable for supercells. It still appears one or two dominant, prefrontal, mid/late-afternoon supercells may evolve and remain south of the front. The potential for a strong tornado in addition to giant hail will be the primary hazards with these warm sector supercells. Additional storm development is expected by early evening with an amassing of cold pools eventually expected, as southeasterly 850mb flow strengthens. A severe MCS will likely evolve during the evening and probably persist into the overnight as it moves east across portions of the Edwards Plateau and central TX. Have expanded wind probabilities farther east to account for a lingering threat for severe gusts and perhaps a localized risk for a tornado late as this activity moves east of I-35. ...North/northeast TX to mid Mississippi Valley/western Great Lakes vicinity... A diurnal intensification of isolated to scattered thunderstorms is expected this afternoon within this general corridor from the Red River Valley northeastward into the IL/WI vicinity. With much of this region located in between larger-scale mid-level waves, modest kinematic fields will tend to limit overall storm organization and severe potential. Nonetheless, heating of a moist boundary layer will facilitate the development of moderate instability by early to mid afternoon. Mainly semi-organized bands of multicells and clusters thereof will occasionally result in sporadic potential for wind damage and large hail. It appears perhaps a corridor for greater wind damage potential may occur immediately ahead/downstream of an MCV moving east across the mid MS Valley. Model guidance indicates slightly greater organized line segments and wind potential later this afternoon from central into northern portions of IL. Have also expanded the MRGL northward into portions of WI where sufficient destabilization will occur ahead of a front and associated mid-level disturbance over the Upper Midwest. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0258 PM CDT Sat May 04 2024 Valid 042000Z - 051200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR WEST TEXAS... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF NORTHWEST/WEST-CENTRAL ILLINOIS... ...SUMMARY... Scattered severe thunderstorms are expected across parts of the southern High Plains into the Hill Country of central Texas this afternoon and evening. Several storms may produce very large hail, and a couple strong tornadoes are possible. ...20Z Update... ...Far West Texas into TX Hill Country/Central TX... Outflow-augmented cold front continues to surge southward across the Permian Basin. Development along the front has been relatively short-lived thus far, primarily due to the undercutting of the updrafts. Even so, buoyancy is building north of the front, so more storm maturation and increasing severe potential appears possible north of the front. A more thermodynamically favorable environment exists south of the surging cold front, where there is a greater potential for surface-based storms capable of all severe hazards, including tornadoes. This initially more discrete activity will likely increase in coverage later this evening as the shortwave trough currently moving through northern Mexico reaches Far West Texas. Some potential for upscale growth exists as forcing increasing, with the resulting MCS then pushing eastward through the Hill Country. Damaging wind gusts will be the primary hazards with this convective line. However, ample low-level moisture and veering low-level flow could support a few line-embedded QLCS tornadoes. ...Western Illinois... As mentioned in recently issued MCD #630, the airmass ahead of the southeastward-progressing cold front will continue to destabilize as dewpoints climb into the mid-60s and temperatures warm into the low 80s. Substantial instability (~1500-2000 J/kg MLCAPE) and modest deep-layer shear will lead to some loosely organized multicell thunderstorms capable of isolated hail and damaging gusts along and ahead of the front later this afternoon. ..Mosier.. 05/04/2024 .PREV DISCUSSION... /ISSUED 1142 AM CDT Sat May 04 2024/ ...TX/southern OK/extreme southeastern NM... Not much change for this outlook update other than a minor southward shift of severe probabilities across far southeast NM and West TX to account for the projected cold front position by mid afternoon. Still expecting widely scattered to scattered thunderstorms to form this afternoon along and behind the cold front over west TX and southeastern NM, as well as ahead of the cold front, near the dryline and over strongly heated, relatively high elevations west of the Pecos Valley. The stronger updrafts will attain supercell characteristics and pose a large-hail threat on both sides of the front, with severe-wind and tornado potential more prevalent to its south. Forecast soundings south of the front indicate veering and increasing flow with height which will become very favorable for supercells. It still appears one or two dominant, prefrontal, mid/late-afternoon supercells may evolve and remain south of the front. The potential for a strong tornado in addition to giant hail will be the primary hazards with these warm sector supercells. Additional storm development is expected by early evening with an amassing of cold pools eventually expected, as southeasterly 850mb flow strengthens. A severe MCS will likely evolve during the evening and probably persist into the overnight as it moves east across portions of the Edwards Plateau and central TX. Have expanded wind probabilities farther east to account for a lingering threat for severe gusts and perhaps a localized risk for a tornado late as this activity moves east of I-35. ...North/northeast TX to mid Mississippi Valley/western Great Lakes vicinity... A diurnal intensification of isolated to scattered thunderstorms is expected this afternoon within this general corridor from the Red River Valley northeastward into the IL/WI vicinity. With much of this region located in between larger-scale mid-level waves, modest kinematic fields will tend to limit overall storm organization and severe potential. Nonetheless, heating of a moist boundary layer will facilitate the development of moderate instability by early to mid afternoon. Mainly semi-organized bands of multicells and clusters thereof will occasionally result in sporadic potential for wind damage and large hail. It appears perhaps a corridor for greater wind damage potential may occur immediately ahead/downstream of an MCV moving east across the mid MS Valley. Model guidance indicates slightly greater organized line segments and wind potential later this afternoon from central into northern portions of IL. Have also expanded the MRGL northward into portions of WI where sufficient destabilization will occur ahead of a front and associated mid-level disturbance over the Upper Midwest. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0258 PM CDT Sat May 04 2024 Valid 042000Z - 051200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR WEST TEXAS... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF NORTHWEST/WEST-CENTRAL ILLINOIS... ...SUMMARY... Scattered severe thunderstorms are expected across parts of the southern High Plains into the Hill Country of central Texas this afternoon and evening. Several storms may produce very large hail, and a couple strong tornadoes are possible. ...20Z Update... ...Far West Texas into TX Hill Country/Central TX... Outflow-augmented cold front continues to surge southward across the Permian Basin. Development along the front has been relatively short-lived thus far, primarily due to the undercutting of the updrafts. Even so, buoyancy is building north of the front, so more storm maturation and increasing severe potential appears possible north of the front. A more thermodynamically favorable environment exists south of the surging cold front, where there is a greater potential for surface-based storms capable of all severe hazards, including tornadoes. This initially more discrete activity will likely increase in coverage later this evening as the shortwave trough currently moving through northern Mexico reaches Far West Texas. Some potential for upscale growth exists as forcing increasing, with the resulting MCS then pushing eastward through the Hill Country. Damaging wind gusts will be the primary hazards with this convective line. However, ample low-level moisture and veering low-level flow could support a few line-embedded QLCS tornadoes. ...Western Illinois... As mentioned in recently issued MCD #630, the airmass ahead of the southeastward-progressing cold front will continue to destabilize as dewpoints climb into the mid-60s and temperatures warm into the low 80s. Substantial instability (~1500-2000 J/kg MLCAPE) and modest deep-layer shear will lead to some loosely organized multicell thunderstorms capable of isolated hail and damaging gusts along and ahead of the front later this afternoon. ..Mosier.. 05/04/2024 .PREV DISCUSSION... /ISSUED 1142 AM CDT Sat May 04 2024/ ...TX/southern OK/extreme southeastern NM... Not much change for this outlook update other than a minor southward shift of severe probabilities across far southeast NM and West TX to account for the projected cold front position by mid afternoon. Still expecting widely scattered to scattered thunderstorms to form this afternoon along and behind the cold front over west TX and southeastern NM, as well as ahead of the cold front, near the dryline and over strongly heated, relatively high elevations west of the Pecos Valley. The stronger updrafts will attain supercell characteristics and pose a large-hail threat on both sides of the front, with severe-wind and tornado potential more prevalent to its south. Forecast soundings south of the front indicate veering and increasing flow with height which will become very favorable for supercells. It still appears one or two dominant, prefrontal, mid/late-afternoon supercells may evolve and remain south of the front. The potential for a strong tornado in addition to giant hail will be the primary hazards with these warm sector supercells. Additional storm development is expected by early evening with an amassing of cold pools eventually expected, as southeasterly 850mb flow strengthens. A severe MCS will likely evolve during the evening and probably persist into the overnight as it moves east across portions of the Edwards Plateau and central TX. Have expanded wind probabilities farther east to account for a lingering threat for severe gusts and perhaps a localized risk for a tornado late as this activity moves east of I-35. ...North/northeast TX to mid Mississippi Valley/western Great Lakes vicinity... A diurnal intensification of isolated to scattered thunderstorms is expected this afternoon within this general corridor from the Red River Valley northeastward into the IL/WI vicinity. With much of this region located in between larger-scale mid-level waves, modest kinematic fields will tend to limit overall storm organization and severe potential. Nonetheless, heating of a moist boundary layer will facilitate the development of moderate instability by early to mid afternoon. Mainly semi-organized bands of multicells and clusters thereof will occasionally result in sporadic potential for wind damage and large hail. It appears perhaps a corridor for greater wind damage potential may occur immediately ahead/downstream of an MCV moving east across the mid MS Valley. Model guidance indicates slightly greater organized line segments and wind potential later this afternoon from central into northern portions of IL. Have also expanded the MRGL northward into portions of WI where sufficient destabilization will occur ahead of a front and associated mid-level disturbance over the Upper Midwest. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0258 PM CDT Sat May 04 2024 Valid 042000Z - 051200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR WEST TEXAS... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF NORTHWEST/WEST-CENTRAL ILLINOIS... ...SUMMARY... Scattered severe thunderstorms are expected across parts of the southern High Plains into the Hill Country of central Texas this afternoon and evening. Several storms may produce very large hail, and a couple strong tornadoes are possible. ...20Z Update... ...Far West Texas into TX Hill Country/Central TX... Outflow-augmented cold front continues to surge southward across the Permian Basin. Development along the front has been relatively short-lived thus far, primarily due to the undercutting of the updrafts. Even so, buoyancy is building north of the front, so more storm maturation and increasing severe potential appears possible north of the front. A more thermodynamically favorable environment exists south of the surging cold front, where there is a greater potential for surface-based storms capable of all severe hazards, including tornadoes. This initially more discrete activity will likely increase in coverage later this evening as the shortwave trough currently moving through northern Mexico reaches Far West Texas. Some potential for upscale growth exists as forcing increasing, with the resulting MCS then pushing eastward through the Hill Country. Damaging wind gusts will be the primary hazards with this convective line. However, ample low-level moisture and veering low-level flow could support a few line-embedded QLCS tornadoes. ...Western Illinois... As mentioned in recently issued MCD #630, the airmass ahead of the southeastward-progressing cold front will continue to destabilize as dewpoints climb into the mid-60s and temperatures warm into the low 80s. Substantial instability (~1500-2000 J/kg MLCAPE) and modest deep-layer shear will lead to some loosely organized multicell thunderstorms capable of isolated hail and damaging gusts along and ahead of the front later this afternoon. ..Mosier.. 05/04/2024 .PREV DISCUSSION... /ISSUED 1142 AM CDT Sat May 04 2024/ ...TX/southern OK/extreme southeastern NM... Not much change for this outlook update other than a minor southward shift of severe probabilities across far southeast NM and West TX to account for the projected cold front position by mid afternoon. Still expecting widely scattered to scattered thunderstorms to form this afternoon along and behind the cold front over west TX and southeastern NM, as well as ahead of the cold front, near the dryline and over strongly heated, relatively high elevations west of the Pecos Valley. The stronger updrafts will attain supercell characteristics and pose a large-hail threat on both sides of the front, with severe-wind and tornado potential more prevalent to its south. Forecast soundings south of the front indicate veering and increasing flow with height which will become very favorable for supercells. It still appears one or two dominant, prefrontal, mid/late-afternoon supercells may evolve and remain south of the front. The potential for a strong tornado in addition to giant hail will be the primary hazards with these warm sector supercells. Additional storm development is expected by early evening with an amassing of cold pools eventually expected, as southeasterly 850mb flow strengthens. A severe MCS will likely evolve during the evening and probably persist into the overnight as it moves east across portions of the Edwards Plateau and central TX. Have expanded wind probabilities farther east to account for a lingering threat for severe gusts and perhaps a localized risk for a tornado late as this activity moves east of I-35. ...North/northeast TX to mid Mississippi Valley/western Great Lakes vicinity... A diurnal intensification of isolated to scattered thunderstorms is expected this afternoon within this general corridor from the Red River Valley northeastward into the IL/WI vicinity. With much of this region located in between larger-scale mid-level waves, modest kinematic fields will tend to limit overall storm organization and severe potential. Nonetheless, heating of a moist boundary layer will facilitate the development of moderate instability by early to mid afternoon. Mainly semi-organized bands of multicells and clusters thereof will occasionally result in sporadic potential for wind damage and large hail. It appears perhaps a corridor for greater wind damage potential may occur immediately ahead/downstream of an MCV moving east across the mid MS Valley. Model guidance indicates slightly greater organized line segments and wind potential later this afternoon from central into northern portions of IL. Have also expanded the MRGL northward into portions of WI where sufficient destabilization will occur ahead of a front and associated mid-level disturbance over the Upper Midwest. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0258 PM CDT Sat May 04 2024 Valid 042000Z - 051200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR WEST TEXAS... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF NORTHWEST/WEST-CENTRAL ILLINOIS... ...SUMMARY... Scattered severe thunderstorms are expected across parts of the southern High Plains into the Hill Country of central Texas this afternoon and evening. Several storms may produce very large hail, and a couple strong tornadoes are possible. ...20Z Update... ...Far West Texas into TX Hill Country/Central TX... Outflow-augmented cold front continues to surge southward across the Permian Basin. Development along the front has been relatively short-lived thus far, primarily due to the undercutting of the updrafts. Even so, buoyancy is building north of the front, so more storm maturation and increasing severe potential appears possible north of the front. A more thermodynamically favorable environment exists south of the surging cold front, where there is a greater potential for surface-based storms capable of all severe hazards, including tornadoes. This initially more discrete activity will likely increase in coverage later this evening as the shortwave trough currently moving through northern Mexico reaches Far West Texas. Some potential for upscale growth exists as forcing increasing, with the resulting MCS then pushing eastward through the Hill Country. Damaging wind gusts will be the primary hazards with this convective line. However, ample low-level moisture and veering low-level flow could support a few line-embedded QLCS tornadoes. ...Western Illinois... As mentioned in recently issued MCD #630, the airmass ahead of the southeastward-progressing cold front will continue to destabilize as dewpoints climb into the mid-60s and temperatures warm into the low 80s. Substantial instability (~1500-2000 J/kg MLCAPE) and modest deep-layer shear will lead to some loosely organized multicell thunderstorms capable of isolated hail and damaging gusts along and ahead of the front later this afternoon. ..Mosier.. 05/04/2024 .PREV DISCUSSION... /ISSUED 1142 AM CDT Sat May 04 2024/ ...TX/southern OK/extreme southeastern NM... Not much change for this outlook update other than a minor southward shift of severe probabilities across far southeast NM and West TX to account for the projected cold front position by mid afternoon. Still expecting widely scattered to scattered thunderstorms to form this afternoon along and behind the cold front over west TX and southeastern NM, as well as ahead of the cold front, near the dryline and over strongly heated, relatively high elevations west of the Pecos Valley. The stronger updrafts will attain supercell characteristics and pose a large-hail threat on both sides of the front, with severe-wind and tornado potential more prevalent to its south. Forecast soundings south of the front indicate veering and increasing flow with height which will become very favorable for supercells. It still appears one or two dominant, prefrontal, mid/late-afternoon supercells may evolve and remain south of the front. The potential for a strong tornado in addition to giant hail will be the primary hazards with these warm sector supercells. Additional storm development is expected by early evening with an amassing of cold pools eventually expected, as southeasterly 850mb flow strengthens. A severe MCS will likely evolve during the evening and probably persist into the overnight as it moves east across portions of the Edwards Plateau and central TX. Have expanded wind probabilities farther east to account for a lingering threat for severe gusts and perhaps a localized risk for a tornado late as this activity moves east of I-35. ...North/northeast TX to mid Mississippi Valley/western Great Lakes vicinity... A diurnal intensification of isolated to scattered thunderstorms is expected this afternoon within this general corridor from the Red River Valley northeastward into the IL/WI vicinity. With much of this region located in between larger-scale mid-level waves, modest kinematic fields will tend to limit overall storm organization and severe potential. Nonetheless, heating of a moist boundary layer will facilitate the development of moderate instability by early to mid afternoon. Mainly semi-organized bands of multicells and clusters thereof will occasionally result in sporadic potential for wind damage and large hail. It appears perhaps a corridor for greater wind damage potential may occur immediately ahead/downstream of an MCV moving east across the mid MS Valley. Model guidance indicates slightly greater organized line segments and wind potential later this afternoon from central into northern portions of IL. Have also expanded the MRGL northward into portions of WI where sufficient destabilization will occur ahead of a front and associated mid-level disturbance over the Upper Midwest. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0258 PM CDT Sat May 04 2024 Valid 042000Z - 051200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR WEST TEXAS... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF NORTHWEST/WEST-CENTRAL ILLINOIS... ...SUMMARY... Scattered severe thunderstorms are expected across parts of the southern High Plains into the Hill Country of central Texas this afternoon and evening. Several storms may produce very large hail, and a couple strong tornadoes are possible. ...20Z Update... ...Far West Texas into TX Hill Country/Central TX... Outflow-augmented cold front continues to surge southward across the Permian Basin. Development along the front has been relatively short-lived thus far, primarily due to the undercutting of the updrafts. Even so, buoyancy is building north of the front, so more storm maturation and increasing severe potential appears possible north of the front. A more thermodynamically favorable environment exists south of the surging cold front, where there is a greater potential for surface-based storms capable of all severe hazards, including tornadoes. This initially more discrete activity will likely increase in coverage later this evening as the shortwave trough currently moving through northern Mexico reaches Far West Texas. Some potential for upscale growth exists as forcing increasing, with the resulting MCS then pushing eastward through the Hill Country. Damaging wind gusts will be the primary hazards with this convective line. However, ample low-level moisture and veering low-level flow could support a few line-embedded QLCS tornadoes. ...Western Illinois... As mentioned in recently issued MCD #630, the airmass ahead of the southeastward-progressing cold front will continue to destabilize as dewpoints climb into the mid-60s and temperatures warm into the low 80s. Substantial instability (~1500-2000 J/kg MLCAPE) and modest deep-layer shear will lead to some loosely organized multicell thunderstorms capable of isolated hail and damaging gusts along and ahead of the front later this afternoon. ..Mosier.. 05/04/2024 .PREV DISCUSSION... /ISSUED 1142 AM CDT Sat May 04 2024/ ...TX/southern OK/extreme southeastern NM... Not much change for this outlook update other than a minor southward shift of severe probabilities across far southeast NM and West TX to account for the projected cold front position by mid afternoon. Still expecting widely scattered to scattered thunderstorms to form this afternoon along and behind the cold front over west TX and southeastern NM, as well as ahead of the cold front, near the dryline and over strongly heated, relatively high elevations west of the Pecos Valley. The stronger updrafts will attain supercell characteristics and pose a large-hail threat on both sides of the front, with severe-wind and tornado potential more prevalent to its south. Forecast soundings south of the front indicate veering and increasing flow with height which will become very favorable for supercells. It still appears one or two dominant, prefrontal, mid/late-afternoon supercells may evolve and remain south of the front. The potential for a strong tornado in addition to giant hail will be the primary hazards with these warm sector supercells. Additional storm development is expected by early evening with an amassing of cold pools eventually expected, as southeasterly 850mb flow strengthens. A severe MCS will likely evolve during the evening and probably persist into the overnight as it moves east across portions of the Edwards Plateau and central TX. Have expanded wind probabilities farther east to account for a lingering threat for severe gusts and perhaps a localized risk for a tornado late as this activity moves east of I-35. ...North/northeast TX to mid Mississippi Valley/western Great Lakes vicinity... A diurnal intensification of isolated to scattered thunderstorms is expected this afternoon within this general corridor from the Red River Valley northeastward into the IL/WI vicinity. With much of this region located in between larger-scale mid-level waves, modest kinematic fields will tend to limit overall storm organization and severe potential. Nonetheless, heating of a moist boundary layer will facilitate the development of moderate instability by early to mid afternoon. Mainly semi-organized bands of multicells and clusters thereof will occasionally result in sporadic potential for wind damage and large hail. It appears perhaps a corridor for greater wind damage potential may occur immediately ahead/downstream of an MCV moving east across the mid MS Valley. Model guidance indicates slightly greater organized line segments and wind potential later this afternoon from central into northern portions of IL. Have also expanded the MRGL northward into portions of WI where sufficient destabilization will occur ahead of a front and associated mid-level disturbance over the Upper Midwest. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0258 PM CDT Sat May 04 2024 Valid 042000Z - 051200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR WEST TEXAS... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF NORTHWEST/WEST-CENTRAL ILLINOIS... ...SUMMARY... Scattered severe thunderstorms are expected across parts of the southern High Plains into the Hill Country of central Texas this afternoon and evening. Several storms may produce very large hail, and a couple strong tornadoes are possible. ...20Z Update... ...Far West Texas into TX Hill Country/Central TX... Outflow-augmented cold front continues to surge southward across the Permian Basin. Development along the front has been relatively short-lived thus far, primarily due to the undercutting of the updrafts. Even so, buoyancy is building north of the front, so more storm maturation and increasing severe potential appears possible north of the front. A more thermodynamically favorable environment exists south of the surging cold front, where there is a greater potential for surface-based storms capable of all severe hazards, including tornadoes. This initially more discrete activity will likely increase in coverage later this evening as the shortwave trough currently moving through northern Mexico reaches Far West Texas. Some potential for upscale growth exists as forcing increasing, with the resulting MCS then pushing eastward through the Hill Country. Damaging wind gusts will be the primary hazards with this convective line. However, ample low-level moisture and veering low-level flow could support a few line-embedded QLCS tornadoes. ...Western Illinois... As mentioned in recently issued MCD #630, the airmass ahead of the southeastward-progressing cold front will continue to destabilize as dewpoints climb into the mid-60s and temperatures warm into the low 80s. Substantial instability (~1500-2000 J/kg MLCAPE) and modest deep-layer shear will lead to some loosely organized multicell thunderstorms capable of isolated hail and damaging gusts along and ahead of the front later this afternoon. ..Mosier.. 05/04/2024 .PREV DISCUSSION... /ISSUED 1142 AM CDT Sat May 04 2024/ ...TX/southern OK/extreme southeastern NM... Not much change for this outlook update other than a minor southward shift of severe probabilities across far southeast NM and West TX to account for the projected cold front position by mid afternoon. Still expecting widely scattered to scattered thunderstorms to form this afternoon along and behind the cold front over west TX and southeastern NM, as well as ahead of the cold front, near the dryline and over strongly heated, relatively high elevations west of the Pecos Valley. The stronger updrafts will attain supercell characteristics and pose a large-hail threat on both sides of the front, with severe-wind and tornado potential more prevalent to its south. Forecast soundings south of the front indicate veering and increasing flow with height which will become very favorable for supercells. It still appears one or two dominant, prefrontal, mid/late-afternoon supercells may evolve and remain south of the front. The potential for a strong tornado in addition to giant hail will be the primary hazards with these warm sector supercells. Additional storm development is expected by early evening with an amassing of cold pools eventually expected, as southeasterly 850mb flow strengthens. A severe MCS will likely evolve during the evening and probably persist into the overnight as it moves east across portions of the Edwards Plateau and central TX. Have expanded wind probabilities farther east to account for a lingering threat for severe gusts and perhaps a localized risk for a tornado late as this activity moves east of I-35. ...North/northeast TX to mid Mississippi Valley/western Great Lakes vicinity... A diurnal intensification of isolated to scattered thunderstorms is expected this afternoon within this general corridor from the Red River Valley northeastward into the IL/WI vicinity. With much of this region located in between larger-scale mid-level waves, modest kinematic fields will tend to limit overall storm organization and severe potential. Nonetheless, heating of a moist boundary layer will facilitate the development of moderate instability by early to mid afternoon. Mainly semi-organized bands of multicells and clusters thereof will occasionally result in sporadic potential for wind damage and large hail. It appears perhaps a corridor for greater wind damage potential may occur immediately ahead/downstream of an MCV moving east across the mid MS Valley. Model guidance indicates slightly greater organized line segments and wind potential later this afternoon from central into northern portions of IL. Have also expanded the MRGL northward into portions of WI where sufficient destabilization will occur ahead of a front and associated mid-level disturbance over the Upper Midwest. Read more

MD 0629 CONCERNING SEVERE POTENTIAL...WATCH LIKELY FOR WEST TO SOUTHWEST TEXAS
Mesoscale Discussion 0629 NWS Storm Prediction Center Norman OK 1236 PM CDT Sat May 04 2024 Areas affected...West to southwest Texas Concerning...Severe potential...Watch likely Valid 041736Z - 042000Z Probability of Watch Issuance...80 percent SUMMARY...Thunderstorm development along a southward-surging cold front is likely within the next 1-2 hours with additional convection expected later this afternoon across southwest TX. Given a favorable environment for organized severe convection, one or more watches will likely be needed in the coming hours. DISCUSSION...Transient convection, along with a more robust cell near Snyder, TX, is noted along and just behind a surface cold front per regional radar and GOES visible/IR imagery at around 17:30 UTC. Aside from the Snyder, TX cell, this convection has been short-lived so far, likely owing to rapid displacement of initial updrafts onto the cool side of the boundary. The development of additional deep/robust convection is probable in the next couple of hours as the downstream air mass continues to destabilize. Initial cells will continue to be displaced along/behind the boundary given boundary-parallel mean flow and post-frontal deep-layer shear vectors. However, MUCAPE within the post-frontal air mass coupled with elongated hodographs should support a few more intense storms capable of large to very large hail. Further south ahead of the cold front, RAP mesoanalyses suggests MLCIN is slowly eroding. However, convective initiation appears less imminent based on latest visible imagery trends. Morning CAM guidance suggests thunderstorm development along/ahead of the dryline is most probable during the 18-21 UTC period closer to peak diurnal heating and as modest ascent ahead of an approaching upper wave overspreads the region. Thunderstorms developing within the warm sector (most likely off the Davis Mountains where shallow cumulus is beginning to develop) will likely evolve into high-based supercells with a risk for large to very large hail. The tornado risk is expected to increase through late afternoon and early evening as cells migrate eastward into an increasingly moist air mass with strengthening southeasterly winds (which should bolster effective SRH to around 150 m2/s2). Given these two regimes, a severe thunderstorm watch will likely be needed for locations north of the cold front with a tornado watch required for areas south of the boundary. Convective trends along the cold front and dryline/higher terrain will continue to be monitored to determine exact timing of either watch issuance. ..Moore/Smith.. 05/04/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...FWD...EWX...SJT...LUB...MAF... LAT...LON 29670283 29820339 30930348 31810370 32270368 32960318 33290257 33530184 33490034 33299967 32899924 32139904 31559905 31329913 30869945 30390011 30010091 29740166 29730237 29670283 Read more

WW 0183 Status Updates
STATUS REPORT ON WW 183 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..MOORE..05/04/24 ATTN...WFO...MAF...SJT...LUB... STATUS REPORT FOR WS 183 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS NMC015-025-042040- NM . NEW MEXICO COUNTIES INCLUDED ARE EDDY LEA TXC003-033-049-059-081-083-115-135-151-165-169-173-207-227-253- 263-301-305-317-329-335-353-399-415-417-431-433-441-445-447-495- 501-042040- TX . TEXAS COUNTIES INCLUDED ARE ANDREWS BORDEN BROWN CALLAHAN COKE COLEMAN DAWSON ECTOR FISHER GAINES GARZA GLASSCOCK HASKELL HOWARD JONES KENT LOVING LYNN MARTIN MIDLAND MITCHELL NOLAN RUNNELS SCURRY SHACKELFORD STERLING STONEWALL TAYLOR TERRY THROCKMORTON WINKLER YOAKUM Read more

WW 0183 Status Updates
STATUS REPORT ON WW 183 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..MOORE..05/04/24 ATTN...WFO...MAF...SJT...LUB... STATUS REPORT FOR WS 183 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS NMC015-025-042040- NM . NEW MEXICO COUNTIES INCLUDED ARE EDDY LEA TXC003-033-049-059-081-083-115-135-151-165-169-173-207-227-253- 263-301-305-317-329-335-353-399-415-417-431-433-441-445-447-495- 501-042040- TX . TEXAS COUNTIES INCLUDED ARE ANDREWS BORDEN BROWN CALLAHAN COKE COLEMAN DAWSON ECTOR FISHER GAINES GARZA GLASSCOCK HASKELL HOWARD JONES KENT LOVING LYNN MARTIN MIDLAND MITCHELL NOLAN RUNNELS SCURRY SHACKELFORD STERLING STONEWALL TAYLOR TERRY THROCKMORTON WINKLER YOAKUM Read more

WW 0184 Status Updates
STATUS FOR WATCH 0184 HAS NOT BEEN ISSUED YET Read more

WW 0183 Status Updates
STATUS FOR WATCH 0183 HAS NOT BEEN ISSUED YET Read more

No watches are valid as of Sat May 4 17:56:02 UTC 2024.

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 PM CDT Sat May 04 2024 Valid 051200Z - 061200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE TEXAS HILL COUNTRY INTO THE MIDDLE TEXAS COASTAL PLAIN... ...SUMMARY... Strong to severe thunderstorms may occur Sunday across parts of the southern Plains into the ArkLaTex and Mid-South, and separately over portions of Ohio into western Pennsylvania. Highest severe thunderstorm potential is expected from the Texas Hill Country into the Middle Texas Coastal Plain. ...Synopsis... A southern-stream shortwave trough, likely enhanced somewhat by widespread thunderstorms Saturday night, is expected to begin the period extended from central OK through southeast TX. This shortwave is forecast to make steady northeastward progress throughout the day, reaching the Lower OH Valley by late Sunday night/early Monday morning. A separate north-stream shortwave trough will likely will move across Ontario and western Quebec, with an attendant surface low moving just ahead of this wave. An associated cold front will extend southwestward from this low, and is expected to progress eastward across the OH Valley throughout the day. Southern portion of this front (i.e. from the Mid-South into central TX) will remain largely stationary throughout the day, before then transitioning to a warm front amid strengthening return flow overnight. Farther west, a deep upper cyclone is forecast to progress eastward across the Great Basin before devolving into more of an open wave as it moves through the central Rockies and into the central High Plains. Strong mid-level flow will accompany this system, spreading eastward and reaching the southern/central High Plains by early Monday morning. ...Southern Plains into the ArkLaTex and Mid-South... Showers and thunderstorms will likely be ongoing from eastern OK into central and southeast TX at the start of the period early Sunday morning, although with varying convective modes. A more linear, modestly organized convective line may be ongoing across southeast TX, remnant from Saturday night/early Sunday morning activity across central TX. Gradually decreasing buoyancy should lead to gradual weakening of this line as it moves into west-central/southwest LA. Even so, given the potentially organized character to the line, some damaging gust will still be possible. A more multicellular mode is anticipated throughout the day from eastern OK into the Arklatex and Mid-South, supported by persistent forcing for ascent and modest buoyancy. A few stronger updrafts capable of hail are possible, with some limited potential for a few bowing segments capable of damaging gusts as well. Farther west, an outflow boundary is expected to extend westward from this decaying convective line, likely from the middle TX Coastal Plain through the Hill Country into the Edwards Plateau. This boundary will likely provide the focus for addition thunderstorm activity during afternoon. Ample low-level moisture, strong buoyancy, and moderate deep-layer shear support the potential for supercells with any discrete development. Large hail is primary hazard with initial development, but some trend towards upscale growth is likely, with the resulting convective line tracking along the outflow boundary. Mesoscale nature of this scenario does lead to some uncertainty, particularly on the location of the outflow boundary, but guidance is consistent enough to delineate higher probabilities from the TX Hill Country into the Middle TX Coastal Plain. ...Ohio into Western Pennsylvania... As mentioned in the synopsis, a weak front is forecast to move eastward across the OH Valley Sunday. Modest destabilization should occur ahead of this front across OH and western PA, contributing to the potential for isolated to scattered thunderstorms along and ahead of this boundary. Deep-layer shear of 20-30 kt should support marginal updraft organization, with occasionally strong to damaging gusts as these storms spread east-southeastward across parts of OH into western PA and vicinity Sunday afternoon and early evening. This activity should gradually weaken through the evening across PA as it encounters a less unstable airmass. ...Northern High Plains... Despite limited low-level moisture and scant buoyancy, increasing mid-level moisture and strengthening large-scale forcing for ascent ahead of the Great Basin shortwave is forecast to support the development of isolated thunderstorms late Sunday evening. Given the high storm bases and strengthening mid/upper flow, a few strong gusts are possible. Even so, the overall severe threat appears too limited to include low severe probabilities with this outlook. ..Mosier.. 05/04/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 PM CDT Sat May 04 2024 Valid 051200Z - 061200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE TEXAS HILL COUNTRY INTO THE MIDDLE TEXAS COASTAL PLAIN... ...SUMMARY... Strong to severe thunderstorms may occur Sunday across parts of the southern Plains into the ArkLaTex and Mid-South, and separately over portions of Ohio into western Pennsylvania. Highest severe thunderstorm potential is expected from the Texas Hill Country into the Middle Texas Coastal Plain. ...Synopsis... A southern-stream shortwave trough, likely enhanced somewhat by widespread thunderstorms Saturday night, is expected to begin the period extended from central OK through southeast TX. This shortwave is forecast to make steady northeastward progress throughout the day, reaching the Lower OH Valley by late Sunday night/early Monday morning. A separate north-stream shortwave trough will likely will move across Ontario and western Quebec, with an attendant surface low moving just ahead of this wave. An associated cold front will extend southwestward from this low, and is expected to progress eastward across the OH Valley throughout the day. Southern portion of this front (i.e. from the Mid-South into central TX) will remain largely stationary throughout the day, before then transitioning to a warm front amid strengthening return flow overnight. Farther west, a deep upper cyclone is forecast to progress eastward across the Great Basin before devolving into more of an open wave as it moves through the central Rockies and into the central High Plains. Strong mid-level flow will accompany this system, spreading eastward and reaching the southern/central High Plains by early Monday morning. ...Southern Plains into the ArkLaTex and Mid-South... Showers and thunderstorms will likely be ongoing from eastern OK into central and southeast TX at the start of the period early Sunday morning, although with varying convective modes. A more linear, modestly organized convective line may be ongoing across southeast TX, remnant from Saturday night/early Sunday morning activity across central TX. Gradually decreasing buoyancy should lead to gradual weakening of this line as it moves into west-central/southwest LA. Even so, given the potentially organized character to the line, some damaging gust will still be possible. A more multicellular mode is anticipated throughout the day from eastern OK into the Arklatex and Mid-South, supported by persistent forcing for ascent and modest buoyancy. A few stronger updrafts capable of hail are possible, with some limited potential for a few bowing segments capable of damaging gusts as well. Farther west, an outflow boundary is expected to extend westward from this decaying convective line, likely from the middle TX Coastal Plain through the Hill Country into the Edwards Plateau. This boundary will likely provide the focus for addition thunderstorm activity during afternoon. Ample low-level moisture, strong buoyancy, and moderate deep-layer shear support the potential for supercells with any discrete development. Large hail is primary hazard with initial development, but some trend towards upscale growth is likely, with the resulting convective line tracking along the outflow boundary. Mesoscale nature of this scenario does lead to some uncertainty, particularly on the location of the outflow boundary, but guidance is consistent enough to delineate higher probabilities from the TX Hill Country into the Middle TX Coastal Plain. ...Ohio into Western Pennsylvania... As mentioned in the synopsis, a weak front is forecast to move eastward across the OH Valley Sunday. Modest destabilization should occur ahead of this front across OH and western PA, contributing to the potential for isolated to scattered thunderstorms along and ahead of this boundary. Deep-layer shear of 20-30 kt should support marginal updraft organization, with occasionally strong to damaging gusts as these storms spread east-southeastward across parts of OH into western PA and vicinity Sunday afternoon and early evening. This activity should gradually weaken through the evening across PA as it encounters a less unstable airmass. ...Northern High Plains... Despite limited low-level moisture and scant buoyancy, increasing mid-level moisture and strengthening large-scale forcing for ascent ahead of the Great Basin shortwave is forecast to support the development of isolated thunderstorms late Sunday evening. Given the high storm bases and strengthening mid/upper flow, a few strong gusts are possible. Even so, the overall severe threat appears too limited to include low severe probabilities with this outlook. ..Mosier.. 05/04/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 PM CDT Sat May 04 2024 Valid 051200Z - 061200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE TEXAS HILL COUNTRY INTO THE MIDDLE TEXAS COASTAL PLAIN... ...SUMMARY... Strong to severe thunderstorms may occur Sunday across parts of the southern Plains into the ArkLaTex and Mid-South, and separately over portions of Ohio into western Pennsylvania. Highest severe thunderstorm potential is expected from the Texas Hill Country into the Middle Texas Coastal Plain. ...Synopsis... A southern-stream shortwave trough, likely enhanced somewhat by widespread thunderstorms Saturday night, is expected to begin the period extended from central OK through southeast TX. This shortwave is forecast to make steady northeastward progress throughout the day, reaching the Lower OH Valley by late Sunday night/early Monday morning. A separate north-stream shortwave trough will likely will move across Ontario and western Quebec, with an attendant surface low moving just ahead of this wave. An associated cold front will extend southwestward from this low, and is expected to progress eastward across the OH Valley throughout the day. Southern portion of this front (i.e. from the Mid-South into central TX) will remain largely stationary throughout the day, before then transitioning to a warm front amid strengthening return flow overnight. Farther west, a deep upper cyclone is forecast to progress eastward across the Great Basin before devolving into more of an open wave as it moves through the central Rockies and into the central High Plains. Strong mid-level flow will accompany this system, spreading eastward and reaching the southern/central High Plains by early Monday morning. ...Southern Plains into the ArkLaTex and Mid-South... Showers and thunderstorms will likely be ongoing from eastern OK into central and southeast TX at the start of the period early Sunday morning, although with varying convective modes. A more linear, modestly organized convective line may be ongoing across southeast TX, remnant from Saturday night/early Sunday morning activity across central TX. Gradually decreasing buoyancy should lead to gradual weakening of this line as it moves into west-central/southwest LA. Even so, given the potentially organized character to the line, some damaging gust will still be possible. A more multicellular mode is anticipated throughout the day from eastern OK into the Arklatex and Mid-South, supported by persistent forcing for ascent and modest buoyancy. A few stronger updrafts capable of hail are possible, with some limited potential for a few bowing segments capable of damaging gusts as well. Farther west, an outflow boundary is expected to extend westward from this decaying convective line, likely from the middle TX Coastal Plain through the Hill Country into the Edwards Plateau. This boundary will likely provide the focus for addition thunderstorm activity during afternoon. Ample low-level moisture, strong buoyancy, and moderate deep-layer shear support the potential for supercells with any discrete development. Large hail is primary hazard with initial development, but some trend towards upscale growth is likely, with the resulting convective line tracking along the outflow boundary. Mesoscale nature of this scenario does lead to some uncertainty, particularly on the location of the outflow boundary, but guidance is consistent enough to delineate higher probabilities from the TX Hill Country into the Middle TX Coastal Plain. ...Ohio into Western Pennsylvania... As mentioned in the synopsis, a weak front is forecast to move eastward across the OH Valley Sunday. Modest destabilization should occur ahead of this front across OH and western PA, contributing to the potential for isolated to scattered thunderstorms along and ahead of this boundary. Deep-layer shear of 20-30 kt should support marginal updraft organization, with occasionally strong to damaging gusts as these storms spread east-southeastward across parts of OH into western PA and vicinity Sunday afternoon and early evening. This activity should gradually weaken through the evening across PA as it encounters a less unstable airmass. ...Northern High Plains... Despite limited low-level moisture and scant buoyancy, increasing mid-level moisture and strengthening large-scale forcing for ascent ahead of the Great Basin shortwave is forecast to support the development of isolated thunderstorms late Sunday evening. Given the high storm bases and strengthening mid/upper flow, a few strong gusts are possible. Even so, the overall severe threat appears too limited to include low severe probabilities with this outlook. ..Mosier.. 05/04/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 PM CDT Sat May 04 2024 Valid 051200Z - 061200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE TEXAS HILL COUNTRY INTO THE MIDDLE TEXAS COASTAL PLAIN... ...SUMMARY... Strong to severe thunderstorms may occur Sunday across parts of the southern Plains into the ArkLaTex and Mid-South, and separately over portions of Ohio into western Pennsylvania. Highest severe thunderstorm potential is expected from the Texas Hill Country into the Middle Texas Coastal Plain. ...Synopsis... A southern-stream shortwave trough, likely enhanced somewhat by widespread thunderstorms Saturday night, is expected to begin the period extended from central OK through southeast TX. This shortwave is forecast to make steady northeastward progress throughout the day, reaching the Lower OH Valley by late Sunday night/early Monday morning. A separate north-stream shortwave trough will likely will move across Ontario and western Quebec, with an attendant surface low moving just ahead of this wave. An associated cold front will extend southwestward from this low, and is expected to progress eastward across the OH Valley throughout the day. Southern portion of this front (i.e. from the Mid-South into central TX) will remain largely stationary throughout the day, before then transitioning to a warm front amid strengthening return flow overnight. Farther west, a deep upper cyclone is forecast to progress eastward across the Great Basin before devolving into more of an open wave as it moves through the central Rockies and into the central High Plains. Strong mid-level flow will accompany this system, spreading eastward and reaching the southern/central High Plains by early Monday morning. ...Southern Plains into the ArkLaTex and Mid-South... Showers and thunderstorms will likely be ongoing from eastern OK into central and southeast TX at the start of the period early Sunday morning, although with varying convective modes. A more linear, modestly organized convective line may be ongoing across southeast TX, remnant from Saturday night/early Sunday morning activity across central TX. Gradually decreasing buoyancy should lead to gradual weakening of this line as it moves into west-central/southwest LA. Even so, given the potentially organized character to the line, some damaging gust will still be possible. A more multicellular mode is anticipated throughout the day from eastern OK into the Arklatex and Mid-South, supported by persistent forcing for ascent and modest buoyancy. A few stronger updrafts capable of hail are possible, with some limited potential for a few bowing segments capable of damaging gusts as well. Farther west, an outflow boundary is expected to extend westward from this decaying convective line, likely from the middle TX Coastal Plain through the Hill Country into the Edwards Plateau. This boundary will likely provide the focus for addition thunderstorm activity during afternoon. Ample low-level moisture, strong buoyancy, and moderate deep-layer shear support the potential for supercells with any discrete development. Large hail is primary hazard with initial development, but some trend towards upscale growth is likely, with the resulting convective line tracking along the outflow boundary. Mesoscale nature of this scenario does lead to some uncertainty, particularly on the location of the outflow boundary, but guidance is consistent enough to delineate higher probabilities from the TX Hill Country into the Middle TX Coastal Plain. ...Ohio into Western Pennsylvania... As mentioned in the synopsis, a weak front is forecast to move eastward across the OH Valley Sunday. Modest destabilization should occur ahead of this front across OH and western PA, contributing to the potential for isolated to scattered thunderstorms along and ahead of this boundary. Deep-layer shear of 20-30 kt should support marginal updraft organization, with occasionally strong to damaging gusts as these storms spread east-southeastward across parts of OH into western PA and vicinity Sunday afternoon and early evening. This activity should gradually weaken through the evening across PA as it encounters a less unstable airmass. ...Northern High Plains... Despite limited low-level moisture and scant buoyancy, increasing mid-level moisture and strengthening large-scale forcing for ascent ahead of the Great Basin shortwave is forecast to support the development of isolated thunderstorms late Sunday evening. Given the high storm bases and strengthening mid/upper flow, a few strong gusts are possible. Even so, the overall severe threat appears too limited to include low severe probabilities with this outlook. ..Mosier.. 05/04/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 PM CDT Sat May 04 2024 Valid 051200Z - 061200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE TEXAS HILL COUNTRY INTO THE MIDDLE TEXAS COASTAL PLAIN... ...SUMMARY... Strong to severe thunderstorms may occur Sunday across parts of the southern Plains into the ArkLaTex and Mid-South, and separately over portions of Ohio into western Pennsylvania. Highest severe thunderstorm potential is expected from the Texas Hill Country into the Middle Texas Coastal Plain. ...Synopsis... A southern-stream shortwave trough, likely enhanced somewhat by widespread thunderstorms Saturday night, is expected to begin the period extended from central OK through southeast TX. This shortwave is forecast to make steady northeastward progress throughout the day, reaching the Lower OH Valley by late Sunday night/early Monday morning. A separate north-stream shortwave trough will likely will move across Ontario and western Quebec, with an attendant surface low moving just ahead of this wave. An associated cold front will extend southwestward from this low, and is expected to progress eastward across the OH Valley throughout the day. Southern portion of this front (i.e. from the Mid-South into central TX) will remain largely stationary throughout the day, before then transitioning to a warm front amid strengthening return flow overnight. Farther west, a deep upper cyclone is forecast to progress eastward across the Great Basin before devolving into more of an open wave as it moves through the central Rockies and into the central High Plains. Strong mid-level flow will accompany this system, spreading eastward and reaching the southern/central High Plains by early Monday morning. ...Southern Plains into the ArkLaTex and Mid-South... Showers and thunderstorms will likely be ongoing from eastern OK into central and southeast TX at the start of the period early Sunday morning, although with varying convective modes. A more linear, modestly organized convective line may be ongoing across southeast TX, remnant from Saturday night/early Sunday morning activity across central TX. Gradually decreasing buoyancy should lead to gradual weakening of this line as it moves into west-central/southwest LA. Even so, given the potentially organized character to the line, some damaging gust will still be possible. A more multicellular mode is anticipated throughout the day from eastern OK into the Arklatex and Mid-South, supported by persistent forcing for ascent and modest buoyancy. A few stronger updrafts capable of hail are possible, with some limited potential for a few bowing segments capable of damaging gusts as well. Farther west, an outflow boundary is expected to extend westward from this decaying convective line, likely from the middle TX Coastal Plain through the Hill Country into the Edwards Plateau. This boundary will likely provide the focus for addition thunderstorm activity during afternoon. Ample low-level moisture, strong buoyancy, and moderate deep-layer shear support the potential for supercells with any discrete development. Large hail is primary hazard with initial development, but some trend towards upscale growth is likely, with the resulting convective line tracking along the outflow boundary. Mesoscale nature of this scenario does lead to some uncertainty, particularly on the location of the outflow boundary, but guidance is consistent enough to delineate higher probabilities from the TX Hill Country into the Middle TX Coastal Plain. ...Ohio into Western Pennsylvania... As mentioned in the synopsis, a weak front is forecast to move eastward across the OH Valley Sunday. Modest destabilization should occur ahead of this front across OH and western PA, contributing to the potential for isolated to scattered thunderstorms along and ahead of this boundary. Deep-layer shear of 20-30 kt should support marginal updraft organization, with occasionally strong to damaging gusts as these storms spread east-southeastward across parts of OH into western PA and vicinity Sunday afternoon and early evening. This activity should gradually weaken through the evening across PA as it encounters a less unstable airmass. ...Northern High Plains... Despite limited low-level moisture and scant buoyancy, increasing mid-level moisture and strengthening large-scale forcing for ascent ahead of the Great Basin shortwave is forecast to support the development of isolated thunderstorms late Sunday evening. Given the high storm bases and strengthening mid/upper flow, a few strong gusts are possible. Even so, the overall severe threat appears too limited to include low severe probabilities with this outlook. ..Mosier.. 05/04/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 PM CDT Sat May 04 2024 Valid 051200Z - 061200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE TEXAS HILL COUNTRY INTO THE MIDDLE TEXAS COASTAL PLAIN... ...SUMMARY... Strong to severe thunderstorms may occur Sunday across parts of the southern Plains into the ArkLaTex and Mid-South, and separately over portions of Ohio into western Pennsylvania. Highest severe thunderstorm potential is expected from the Texas Hill Country into the Middle Texas Coastal Plain. ...Synopsis... A southern-stream shortwave trough, likely enhanced somewhat by widespread thunderstorms Saturday night, is expected to begin the period extended from central OK through southeast TX. This shortwave is forecast to make steady northeastward progress throughout the day, reaching the Lower OH Valley by late Sunday night/early Monday morning. A separate north-stream shortwave trough will likely will move across Ontario and western Quebec, with an attendant surface low moving just ahead of this wave. An associated cold front will extend southwestward from this low, and is expected to progress eastward across the OH Valley throughout the day. Southern portion of this front (i.e. from the Mid-South into central TX) will remain largely stationary throughout the day, before then transitioning to a warm front amid strengthening return flow overnight. Farther west, a deep upper cyclone is forecast to progress eastward across the Great Basin before devolving into more of an open wave as it moves through the central Rockies and into the central High Plains. Strong mid-level flow will accompany this system, spreading eastward and reaching the southern/central High Plains by early Monday morning. ...Southern Plains into the ArkLaTex and Mid-South... Showers and thunderstorms will likely be ongoing from eastern OK into central and southeast TX at the start of the period early Sunday morning, although with varying convective modes. A more linear, modestly organized convective line may be ongoing across southeast TX, remnant from Saturday night/early Sunday morning activity across central TX. Gradually decreasing buoyancy should lead to gradual weakening of this line as it moves into west-central/southwest LA. Even so, given the potentially organized character to the line, some damaging gust will still be possible. A more multicellular mode is anticipated throughout the day from eastern OK into the Arklatex and Mid-South, supported by persistent forcing for ascent and modest buoyancy. A few stronger updrafts capable of hail are possible, with some limited potential for a few bowing segments capable of damaging gusts as well. Farther west, an outflow boundary is expected to extend westward from this decaying convective line, likely from the middle TX Coastal Plain through the Hill Country into the Edwards Plateau. This boundary will likely provide the focus for addition thunderstorm activity during afternoon. Ample low-level moisture, strong buoyancy, and moderate deep-layer shear support the potential for supercells with any discrete development. Large hail is primary hazard with initial development, but some trend towards upscale growth is likely, with the resulting convective line tracking along the outflow boundary. Mesoscale nature of this scenario does lead to some uncertainty, particularly on the location of the outflow boundary, but guidance is consistent enough to delineate higher probabilities from the TX Hill Country into the Middle TX Coastal Plain. ...Ohio into Western Pennsylvania... As mentioned in the synopsis, a weak front is forecast to move eastward across the OH Valley Sunday. Modest destabilization should occur ahead of this front across OH and western PA, contributing to the potential for isolated to scattered thunderstorms along and ahead of this boundary. Deep-layer shear of 20-30 kt should support marginal updraft organization, with occasionally strong to damaging gusts as these storms spread east-southeastward across parts of OH into western PA and vicinity Sunday afternoon and early evening. This activity should gradually weaken through the evening across PA as it encounters a less unstable airmass. ...Northern High Plains... Despite limited low-level moisture and scant buoyancy, increasing mid-level moisture and strengthening large-scale forcing for ascent ahead of the Great Basin shortwave is forecast to support the development of isolated thunderstorms late Sunday evening. Given the high storm bases and strengthening mid/upper flow, a few strong gusts are possible. Even so, the overall severe threat appears too limited to include low severe probabilities with this outlook. ..Mosier.. 05/04/2024 Read more