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SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0155 AM CDT Sat Jul 20 2024 Valid 221200Z - 231200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe-thunderstorm potential appears low on Monday. ...Synopsis... The overall pattern will not change much on Monday. An upper ridge in the West and trough over the central/eastern U.S. will persist amid weak deep-layer flow. A seasonally moist airmass will remain in place east of the Rockies, supporting widespread thunderstorm activity. Much of this activity will likely remain disorganized given weak vertical shear and a little upper support. Some forecast guidance suggests a weak cold front will develop southward across the Canadian Prairies into ND and the Upper Midwest. However, the timing of this feature is uncertain, and may be ill-timed with the diurnal cycle/better thermodynamic conditions. Vertical shear is forecast to remain weak regardless, and confidence is too low to include severe probabilities at this time. Elsewhere, sporadic strong gusts may accompany thunderstorms across the south-central/southeast states where high PW values will be in place, though this activity should remain mostly disorganized, pulse-type convection. ..Leitman.. 07/20/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0155 AM CDT Sat Jul 20 2024 Valid 221200Z - 231200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe-thunderstorm potential appears low on Monday. ...Synopsis... The overall pattern will not change much on Monday. An upper ridge in the West and trough over the central/eastern U.S. will persist amid weak deep-layer flow. A seasonally moist airmass will remain in place east of the Rockies, supporting widespread thunderstorm activity. Much of this activity will likely remain disorganized given weak vertical shear and a little upper support. Some forecast guidance suggests a weak cold front will develop southward across the Canadian Prairies into ND and the Upper Midwest. However, the timing of this feature is uncertain, and may be ill-timed with the diurnal cycle/better thermodynamic conditions. Vertical shear is forecast to remain weak regardless, and confidence is too low to include severe probabilities at this time. Elsewhere, sporadic strong gusts may accompany thunderstorms across the south-central/southeast states where high PW values will be in place, though this activity should remain mostly disorganized, pulse-type convection. ..Leitman.. 07/20/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 AM CDT Sat Jul 20 2024 Valid 211200Z - 221200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe-thunderstorm potential is expected to be low on Sunday. ...Synopsis... A weak mid/upper flow regime will persist with upper ridging over the West and upper troughing over the eastern two-thirds of the CONUS. A seasonally moist and unstable airmass will envelop the south-central and southeast states into the Mid-Atlantic, and less moisture with northward extent across much of the eastern Plains into the Midwest. Widespread thunderstorm activity is expected from the southern/central Rockies into the Plains, Southeast and Mid-Atlantic. A few areas of convectively enhanced vorticity maxima may float through southwesterly flow over the Southeast to the Carolinas, and in northwesterly flow from the central/southern High Plains into OK/TX. Pockets of moderate destabilization will be rather widespread across the vast warm sector east of the Rockies. Sporadic strong storms producing gusty to locally damaging winds are possible across the central/southern Plains vicinity eastward across the southern tier of the U.S. Poor midlevel lapse rates and weak vertical shear, along with a lack of large-scale ascent, will preclude focused areas of organized severe convection. ..Leitman.. 07/20/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 AM CDT Sat Jul 20 2024 Valid 211200Z - 221200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe-thunderstorm potential is expected to be low on Sunday. ...Synopsis... A weak mid/upper flow regime will persist with upper ridging over the West and upper troughing over the eastern two-thirds of the CONUS. A seasonally moist and unstable airmass will envelop the south-central and southeast states into the Mid-Atlantic, and less moisture with northward extent across much of the eastern Plains into the Midwest. Widespread thunderstorm activity is expected from the southern/central Rockies into the Plains, Southeast and Mid-Atlantic. A few areas of convectively enhanced vorticity maxima may float through southwesterly flow over the Southeast to the Carolinas, and in northwesterly flow from the central/southern High Plains into OK/TX. Pockets of moderate destabilization will be rather widespread across the vast warm sector east of the Rockies. Sporadic strong storms producing gusty to locally damaging winds are possible across the central/southern Plains vicinity eastward across the southern tier of the U.S. Poor midlevel lapse rates and weak vertical shear, along with a lack of large-scale ascent, will preclude focused areas of organized severe convection. ..Leitman.. 07/20/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 AM CDT Sat Jul 20 2024 Valid 211200Z - 221200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe-thunderstorm potential is expected to be low on Sunday. ...Synopsis... A weak mid/upper flow regime will persist with upper ridging over the West and upper troughing over the eastern two-thirds of the CONUS. A seasonally moist and unstable airmass will envelop the south-central and southeast states into the Mid-Atlantic, and less moisture with northward extent across much of the eastern Plains into the Midwest. Widespread thunderstorm activity is expected from the southern/central Rockies into the Plains, Southeast and Mid-Atlantic. A few areas of convectively enhanced vorticity maxima may float through southwesterly flow over the Southeast to the Carolinas, and in northwesterly flow from the central/southern High Plains into OK/TX. Pockets of moderate destabilization will be rather widespread across the vast warm sector east of the Rockies. Sporadic strong storms producing gusty to locally damaging winds are possible across the central/southern Plains vicinity eastward across the southern tier of the U.S. Poor midlevel lapse rates and weak vertical shear, along with a lack of large-scale ascent, will preclude focused areas of organized severe convection. ..Leitman.. 07/20/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 AM CDT Sat Jul 20 2024 Valid 211200Z - 221200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe-thunderstorm potential is expected to be low on Sunday. ...Synopsis... A weak mid/upper flow regime will persist with upper ridging over the West and upper troughing over the eastern two-thirds of the CONUS. A seasonally moist and unstable airmass will envelop the south-central and southeast states into the Mid-Atlantic, and less moisture with northward extent across much of the eastern Plains into the Midwest. Widespread thunderstorm activity is expected from the southern/central Rockies into the Plains, Southeast and Mid-Atlantic. A few areas of convectively enhanced vorticity maxima may float through southwesterly flow over the Southeast to the Carolinas, and in northwesterly flow from the central/southern High Plains into OK/TX. Pockets of moderate destabilization will be rather widespread across the vast warm sector east of the Rockies. Sporadic strong storms producing gusty to locally damaging winds are possible across the central/southern Plains vicinity eastward across the southern tier of the U.S. Poor midlevel lapse rates and weak vertical shear, along with a lack of large-scale ascent, will preclude focused areas of organized severe convection. ..Leitman.. 07/20/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 AM CDT Sat Jul 20 2024 Valid 211200Z - 221200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe-thunderstorm potential is expected to be low on Sunday. ...Synopsis... A weak mid/upper flow regime will persist with upper ridging over the West and upper troughing over the eastern two-thirds of the CONUS. A seasonally moist and unstable airmass will envelop the south-central and southeast states into the Mid-Atlantic, and less moisture with northward extent across much of the eastern Plains into the Midwest. Widespread thunderstorm activity is expected from the southern/central Rockies into the Plains, Southeast and Mid-Atlantic. A few areas of convectively enhanced vorticity maxima may float through southwesterly flow over the Southeast to the Carolinas, and in northwesterly flow from the central/southern High Plains into OK/TX. Pockets of moderate destabilization will be rather widespread across the vast warm sector east of the Rockies. Sporadic strong storms producing gusty to locally damaging winds are possible across the central/southern Plains vicinity eastward across the southern tier of the U.S. Poor midlevel lapse rates and weak vertical shear, along with a lack of large-scale ascent, will preclude focused areas of organized severe convection. ..Leitman.. 07/20/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1224 AM CDT Sat Jul 20 2024 Valid 201200Z - 211200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE CENTRAL/SOUTHERN HIGH PLAINS AND THE SOUTHEAST... ...SUMMARY... Strong to isolated severe thunderstorms are possible over parts of the Southeast and central to southern High Plains, mainly from mid-afternoon to evening. ...Central to southern High Plains... A moderate mid-level northwesterly flow regime will persist between an anticyclone over the Great Basin and a low-amplitude trough from the Great Lakes towards the Ozarks. The latter part of this minor trough may be augmented by a southeast-moving MCV from remnants of weakening convection currently over western KS. Scattered to numerous thunderstorms are expected during the afternoon over the central to southern Rockies, spreading across the adjacent High Plains. An additional corridor of scattered thunderstorms may be focused over northwest TX into southwest OK, where differential boundary-layer heating should be more pronounced to the south-southwest of early-day convection/cloud cover. After fairly extensive convection on Friday evening, instability will be comparatively weaker this afternoon. Still, with a moderate combination of buoyancy, characterized by MLCAPE of 1000-2000 J/kg, and deep-layer shear, a few clusters and transient supercells may develop across the region. Cooler-than-normal surface temperatures north of northwest TX suggest the wind threat may be more strong than severe, a signal supported by 00Z HREF guidance. Isolated severe hail may be the primary hazard over the central High Plains. ...Southeast... Between a low-amplitude mid-level trough from the Great Lakes to the Ozarks and the subtropical ridge in the western Atlantic, a belt of modestly enhanced southwesterly 700-500 mb winds should exist across parts of the Southeast from eastern GA to southern VA. Scattered thunderstorms appear most probable during the afternoon in parts of AL/GA/north FL, and separately in the lee of the southern Appalachians to the VA/NC border. Destabilization within the enhanced flow regime should be more pronounced between these regimes over the Carolina Piedmont and coastal plain. Upstream convection may consolidate into loosely organized multicell clusters capable of producing sporadic strong gusts and localized tree damage. ..Grams/Lyons.. 07/20/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1224 AM CDT Sat Jul 20 2024 Valid 201200Z - 211200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE CENTRAL/SOUTHERN HIGH PLAINS AND THE SOUTHEAST... ...SUMMARY... Strong to isolated severe thunderstorms are possible over parts of the Southeast and central to southern High Plains, mainly from mid-afternoon to evening. ...Central to southern High Plains... A moderate mid-level northwesterly flow regime will persist between an anticyclone over the Great Basin and a low-amplitude trough from the Great Lakes towards the Ozarks. The latter part of this minor trough may be augmented by a southeast-moving MCV from remnants of weakening convection currently over western KS. Scattered to numerous thunderstorms are expected during the afternoon over the central to southern Rockies, spreading across the adjacent High Plains. An additional corridor of scattered thunderstorms may be focused over northwest TX into southwest OK, where differential boundary-layer heating should be more pronounced to the south-southwest of early-day convection/cloud cover. After fairly extensive convection on Friday evening, instability will be comparatively weaker this afternoon. Still, with a moderate combination of buoyancy, characterized by MLCAPE of 1000-2000 J/kg, and deep-layer shear, a few clusters and transient supercells may develop across the region. Cooler-than-normal surface temperatures north of northwest TX suggest the wind threat may be more strong than severe, a signal supported by 00Z HREF guidance. Isolated severe hail may be the primary hazard over the central High Plains. ...Southeast... Between a low-amplitude mid-level trough from the Great Lakes to the Ozarks and the subtropical ridge in the western Atlantic, a belt of modestly enhanced southwesterly 700-500 mb winds should exist across parts of the Southeast from eastern GA to southern VA. Scattered thunderstorms appear most probable during the afternoon in parts of AL/GA/north FL, and separately in the lee of the southern Appalachians to the VA/NC border. Destabilization within the enhanced flow regime should be more pronounced between these regimes over the Carolina Piedmont and coastal plain. Upstream convection may consolidate into loosely organized multicell clusters capable of producing sporadic strong gusts and localized tree damage. ..Grams/Lyons.. 07/20/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1224 AM CDT Sat Jul 20 2024 Valid 201200Z - 211200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE CENTRAL/SOUTHERN HIGH PLAINS AND THE SOUTHEAST... ...SUMMARY... Strong to isolated severe thunderstorms are possible over parts of the Southeast and central to southern High Plains, mainly from mid-afternoon to evening. ...Central to southern High Plains... A moderate mid-level northwesterly flow regime will persist between an anticyclone over the Great Basin and a low-amplitude trough from the Great Lakes towards the Ozarks. The latter part of this minor trough may be augmented by a southeast-moving MCV from remnants of weakening convection currently over western KS. Scattered to numerous thunderstorms are expected during the afternoon over the central to southern Rockies, spreading across the adjacent High Plains. An additional corridor of scattered thunderstorms may be focused over northwest TX into southwest OK, where differential boundary-layer heating should be more pronounced to the south-southwest of early-day convection/cloud cover. After fairly extensive convection on Friday evening, instability will be comparatively weaker this afternoon. Still, with a moderate combination of buoyancy, characterized by MLCAPE of 1000-2000 J/kg, and deep-layer shear, a few clusters and transient supercells may develop across the region. Cooler-than-normal surface temperatures north of northwest TX suggest the wind threat may be more strong than severe, a signal supported by 00Z HREF guidance. Isolated severe hail may be the primary hazard over the central High Plains. ...Southeast... Between a low-amplitude mid-level trough from the Great Lakes to the Ozarks and the subtropical ridge in the western Atlantic, a belt of modestly enhanced southwesterly 700-500 mb winds should exist across parts of the Southeast from eastern GA to southern VA. Scattered thunderstorms appear most probable during the afternoon in parts of AL/GA/north FL, and separately in the lee of the southern Appalachians to the VA/NC border. Destabilization within the enhanced flow regime should be more pronounced between these regimes over the Carolina Piedmont and coastal plain. Upstream convection may consolidate into loosely organized multicell clusters capable of producing sporadic strong gusts and localized tree damage. ..Grams/Lyons.. 07/20/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1224 AM CDT Sat Jul 20 2024 Valid 201200Z - 211200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE CENTRAL/SOUTHERN HIGH PLAINS AND THE SOUTHEAST... ...SUMMARY... Strong to isolated severe thunderstorms are possible over parts of the Southeast and central to southern High Plains, mainly from mid-afternoon to evening. ...Central to southern High Plains... A moderate mid-level northwesterly flow regime will persist between an anticyclone over the Great Basin and a low-amplitude trough from the Great Lakes towards the Ozarks. The latter part of this minor trough may be augmented by a southeast-moving MCV from remnants of weakening convection currently over western KS. Scattered to numerous thunderstorms are expected during the afternoon over the central to southern Rockies, spreading across the adjacent High Plains. An additional corridor of scattered thunderstorms may be focused over northwest TX into southwest OK, where differential boundary-layer heating should be more pronounced to the south-southwest of early-day convection/cloud cover. After fairly extensive convection on Friday evening, instability will be comparatively weaker this afternoon. Still, with a moderate combination of buoyancy, characterized by MLCAPE of 1000-2000 J/kg, and deep-layer shear, a few clusters and transient supercells may develop across the region. Cooler-than-normal surface temperatures north of northwest TX suggest the wind threat may be more strong than severe, a signal supported by 00Z HREF guidance. Isolated severe hail may be the primary hazard over the central High Plains. ...Southeast... Between a low-amplitude mid-level trough from the Great Lakes to the Ozarks and the subtropical ridge in the western Atlantic, a belt of modestly enhanced southwesterly 700-500 mb winds should exist across parts of the Southeast from eastern GA to southern VA. Scattered thunderstorms appear most probable during the afternoon in parts of AL/GA/north FL, and separately in the lee of the southern Appalachians to the VA/NC border. Destabilization within the enhanced flow regime should be more pronounced between these regimes over the Carolina Piedmont and coastal plain. Upstream convection may consolidate into loosely organized multicell clusters capable of producing sporadic strong gusts and localized tree damage. ..Grams/Lyons.. 07/20/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1224 AM CDT Sat Jul 20 2024 Valid 201200Z - 211200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE CENTRAL/SOUTHERN HIGH PLAINS AND THE SOUTHEAST... ...SUMMARY... Strong to isolated severe thunderstorms are possible over parts of the Southeast and central to southern High Plains, mainly from mid-afternoon to evening. ...Central to southern High Plains... A moderate mid-level northwesterly flow regime will persist between an anticyclone over the Great Basin and a low-amplitude trough from the Great Lakes towards the Ozarks. The latter part of this minor trough may be augmented by a southeast-moving MCV from remnants of weakening convection currently over western KS. Scattered to numerous thunderstorms are expected during the afternoon over the central to southern Rockies, spreading across the adjacent High Plains. An additional corridor of scattered thunderstorms may be focused over northwest TX into southwest OK, where differential boundary-layer heating should be more pronounced to the south-southwest of early-day convection/cloud cover. After fairly extensive convection on Friday evening, instability will be comparatively weaker this afternoon. Still, with a moderate combination of buoyancy, characterized by MLCAPE of 1000-2000 J/kg, and deep-layer shear, a few clusters and transient supercells may develop across the region. Cooler-than-normal surface temperatures north of northwest TX suggest the wind threat may be more strong than severe, a signal supported by 00Z HREF guidance. Isolated severe hail may be the primary hazard over the central High Plains. ...Southeast... Between a low-amplitude mid-level trough from the Great Lakes to the Ozarks and the subtropical ridge in the western Atlantic, a belt of modestly enhanced southwesterly 700-500 mb winds should exist across parts of the Southeast from eastern GA to southern VA. Scattered thunderstorms appear most probable during the afternoon in parts of AL/GA/north FL, and separately in the lee of the southern Appalachians to the VA/NC border. Destabilization within the enhanced flow regime should be more pronounced between these regimes over the Carolina Piedmont and coastal plain. Upstream convection may consolidate into loosely organized multicell clusters capable of producing sporadic strong gusts and localized tree damage. ..Grams/Lyons.. 07/20/2024 Read more

000
ABPZ20 KNHC 200502
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 PM PDT Fri Jul 19 2024

For the eastern North Pacific...east of 140 degrees west longitude:

Central and Western East Pacific:
A tropical wave located along a monsoon trough well to the south of
the coast of Mexico is producing a broad area of showers and
thunderstorms. Some gradual development of this system is possible
over the next several days as it moves westward to
west-northwestward at 10 to 15 mph, moving into the western portion
of the basin by the middle to latter parts of next week.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...low...20 percent.

$$
Forecaster Beven

WW 0556 Status Updates
STATUS REPORT ON WW 556 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 40 ESE LAA TO 25 E EHA TO 35 NNE BGD. ..SPC..07/20/24 ATTN...WFO...PUB...DDC...AMA...OUN... STATUS REPORT FOR WS 556 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS COC009-200340- CO . COLORADO COUNTIES INCLUDED ARE BACA OKC025-139-200340- OK . OKLAHOMA COUNTIES INCLUDED ARE CIMARRON TEXAS TXC111-195-205-421-200340- TX . TEXAS COUNTIES INCLUDED ARE DALLAM HANSFORD HARTLEY SHERMAN Read more

WW 556 SEVERE TSTM CO KS OK TX 192235Z - 200500Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 556 NWS Storm Prediction Center Norman OK 535 PM CDT Fri Jul 19 2024 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Southeast Colorado Southwest Kansas Far Northwest Oklahoma and the Oklahoma Panhandle The Texas Panhandle * Effective this Friday afternoon from 535 PM until Midnight CDT. * Primary threats include... Scattered damaging winds likely with isolated significant gusts to 75 mph possible Isolated very large hail events to 2 inches in diameter possible SUMMARY...Thunderstorms should generally move southward this evening while posing a threat for scattered damaging winds around 60-70 mph, with isolated stronger gusts possible. Occasional hail around 1-2 inches in diameter may also occur with any persistent supercells. The severe thunderstorm watch area is approximately along and 65 statute miles north and south of a line from 40 miles south southwest of Springfield CO to 55 miles east southeast of Dodge City KS. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU6). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Severe Thunderstorm Watch means conditions are favorable for severe thunderstorms in and close to the watch area. Persons in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings. Severe thunderstorms can and occasionally do produce tornadoes. && OTHER WATCH INFORMATION...CONTINUE...WW 555... AVIATION...A few severe thunderstorms with hail surface and aloft to 2 inches. Extreme turbulence and surface wind gusts to 65 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 34025. ...Gleason Read more

WW 0557 Status Updates
STATUS REPORT ON WW 557 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 15 SE SNY TO 50 E MCK. ..LYONS..07/20/24 ATTN...WFO...BOU...LBF...CYS...UNR... STATUS REPORT FOR WS 557 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS COC095-200340- CO . COLORADO COUNTIES INCLUDED ARE PHILLIPS NEC029-200340- NE . NEBRASKA COUNTIES INCLUDED ARE CHASE THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more

WW 557 SEVERE TSTM CO NE SD 192300Z - 200500Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 557 NWS Storm Prediction Center Norman OK 500 PM MDT Fri Jul 19 2024 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Far Northeast Colorado Western and Central Nebraska Southwest South Dakota * Effective this Friday afternoon and evening from 500 PM until 1100 PM MDT. * Primary threats include... Scattered damaging winds and isolated significant gusts to 75 mph possible Scattered large hail and isolated very large hail events to 2 inches in diameter possible SUMMARY...Ongoing supercells should continue to pose a threat for large hail up to 1-2 inches in diameter as they move generally southward this evening. Some threat for damaging winds around 60-75 mph may also exist, especially if a thunderstorm cluster can develop later this evening. The severe thunderstorm watch area is approximately along and 60 statute miles east and west of a line from 5 miles east northeast of Rapid City SD to 35 miles west southwest of North Platte NE. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU7). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Severe Thunderstorm Watch means conditions are favorable for severe thunderstorms in and close to the watch area. Persons in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings. Severe thunderstorms can and occasionally do produce tornadoes. && OTHER WATCH INFORMATION...CONTINUE...WW 555...WW 556... AVIATION...A few severe thunderstorms with hail surface and aloft to 2 inches. Extreme turbulence and surface wind gusts to 65 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 35025. ...Gleason Read more

WW 0557 Status Updates
STATUS REPORT ON WW 557 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 25 SW BFF TO 10 WSW BBW. ..LYONS..07/20/24 ATTN...WFO...BOU...LBF...CYS...UNR... STATUS REPORT FOR WS 557 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS COC095-115-200240- CO . COLORADO COUNTIES INCLUDED ARE PHILLIPS SEDGWICK NEC029-049-063-085-101-111-135-200240- NE . NEBRASKA COUNTIES INCLUDED ARE CHASE DEUEL FRONTIER HAYES KEITH LINCOLN PERKINS THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more

MD 1685 CONCERNING SEVERE THUNDERSTORM WATCH 555...557... FOR PORTIONS OF SOUTHWEST NEBRASKA AND EXTREME NORTHEAST COLORADO
Mesoscale Discussion 1685 NWS Storm Prediction Center Norman OK 0726 PM CDT Fri Jul 19 2024 Areas affected...Portions of southwest Nebraska and extreme northeast Colorado Concerning...Severe Thunderstorm Watch 555...557... Valid 200026Z - 200130Z The severe weather threat for Severe Thunderstorm Watch 555, 557 continues. SUMMARY...The most favorable corridor for a continued risk for severe hail and wind appears to be over parts of southwest Nebraska and extreme northeast Colorado through at least 02Z. DISCUSSION...The greatest severe risk appears to be focused across portions of southwest Nebraska and perhaps extreme northeast Colorado through around 02Z. Here, temperatures in the lower 90s amid upper 50s/lower 60s dewpoints (lower with westward extent) are still yielding moderate surface-based instability -- given steep midlevel lapse rates (see LBF 00Z sounding). Additionally, regional VWP shows around 40-50 kt of deep-layer shear (with modest low-level hodograph curvature), which will favor a continuation of semi-discrete supercells, capable of producing hail around 2 inches in diameter and gusts upwards of 75 mph. ..Weinman.. 07/20/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LBF...GLD...BOU...CYS... LAT...LON 41000098 40770085 40410061 40140071 40100123 40350205 40610252 41050299 41370315 41680321 41790298 41800268 41590239 41450209 41420172 41390137 41230112 41000098 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0754 PM CDT Fri Jul 19 2024 Valid 200100Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN PARTS OF THE CENTRAL PLAINS... ...SUMMARY... Isolated to scattered severe gusts and isolated severe hail will remain possible this evening across parts of the central Great Plains. ...Central Great Plains... Numerous cells and clusters are ongoing from western SD to the TX Panhandle within a belt of moderate mid-level northwesterlies between an anticyclone over the western Great Basin and a minor mid-level trough over MN. The plume of moderate buoyancy centered on parts of central NE to far northeast CO (and sampled by the 00Z LBF sounding) should become increasingly squeezed by outflows pushing south in western NE and weak southerly low-level flow advecting previously overturned air north from northwest KS. As such, the overall severe threat will likely be greatest over the next couple hours before diminishing as convection spreads southward from the Black Hills and central High Plains region. See MCD 1685 for additional short-term information. Farther south, storms have struggled to greatly intensify over southeast CO and southwest KS. But the 00Z DDC sounding sampled around 1500 J/kg and 35-kt effective bulk shear. This activity will have potential to produce sporadic severe wind and hail through late evening, before further waning amid nocturnally increasing MLCIN. ..Grams.. 07/20/2024 Read more