Severe Storms

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0746 AM CDT Mon Aug 12 2019 Valid 121300Z - 131200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON/EVENING FROM SOUTHEAST IA INTO CENTRAL IL... ...SUMMARY... Severe thunderstorms are likely today over the middle Mississippi Valley to the Ohio Valley. Damaging gusts are the primary risk but a few tornadoes are possible. ...IA/IL this afternoon/evening... A well-defined MCV is moving eastward over western IA this morning, per reflectivity mosaics and VWP observations of 50-60 kt midlevel flow at OAX/DMX. The associated MCS and low-level cold pool have weakened since 09z, though convective outflow appears to extend farther south into KS/MO than most model guidance. Thus, recovery of the boundary layer into IA is a primary concern for this afternoon. Assuming surface heating in cloud breaks by early-mid afternoon and erosion of the morning cold pool, boundary-layer dewpoints in the low-mid 70s will contribute to MLCAPE in excess of 2000 J/kg east of the surface low and south of the warm front in IA. Renewed thunderstorm development is probable by mid afternoon near the surface low, with storms expected to subsequently move/develop east-southeastward along the warm front into IL by this evening. The initial storms will likely be supercells capable of producing tornadoes and damaging winds, given the enhanced low-level shear/hodograph curvature near the cyclone/warm front, along the north edge of the unstable warm sector. Upscale growth into a cluster is expected by this evening from southeast IA/northeast MO into northwest and central IL, where damaging winds will become the more prominent threat into tonight. The MCV/cyclone will begin to move east of the surface warm sector late tonight, which should result in gradual weakening of the storms across IN. The northward extent and magnitude of the severe/tornado threat this afternoon will depend heavily on the degree of recovery from the ongoing/weakening MCS, which is still a bit uncertain. ...TX Panhandle this afternoon to southeast KS tonight... A remnant midlevel trough will drift slowly east-northeastward over the TX Panhandle today, as a weak cold front moves slowly southeastward from KS/CO. Surface heating and deep mixing will result in inverted-v profiles along and south of the front, and will support the potential for isolated strong downburst winds. Convection will tend to develop east-northeastward tonight along the front, with strong downdrafts still possible in an environment of lingering large CAPE/DCAPE. ...Maine this afternoon... A midlevel trough over James Bay will pivot east-southeastward to Maine overnight. In advance of this trough, a weak pre-frontal trough at the surface and band of weak ascent will provide a focus for thunderstorm development this afternoon. Though moisture and lapse rates will be modest, increasing deep-layer westerly shear and surface heating on the south edge of the thicker clouds could support storms capable of producing isolated damaging gusts. ...Dakotas this afternoon/evening... Widespread clouds and rain are spreading slowly eastward across the eastern Dakotas in association with a couple of diffuse MCVs from overnight convection. A little clearing of clouds and surface heating will be possible from west to east this afternoon, in advance of a larger-scale trough moving east-southeastward from MT to ND. Isolated thunderstorm development and a low-end severe threat will be possible this afternoon if sufficient near-surface destabilization occurs, given enough vertical shear for organized storms. ..Thompson/Kerr.. 08/12/2019 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0746 AM CDT Mon Aug 12 2019 Valid 121300Z - 131200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON/EVENING FROM SOUTHEAST IA INTO CENTRAL IL... ...SUMMARY... Severe thunderstorms are likely today over the middle Mississippi Valley to the Ohio Valley. Damaging gusts are the primary risk but a few tornadoes are possible. ...IA/IL this afternoon/evening... A well-defined MCV is moving eastward over western IA this morning, per reflectivity mosaics and VWP observations of 50-60 kt midlevel flow at OAX/DMX. The associated MCS and low-level cold pool have weakened since 09z, though convective outflow appears to extend farther south into KS/MO than most model guidance. Thus, recovery of the boundary layer into IA is a primary concern for this afternoon. Assuming surface heating in cloud breaks by early-mid afternoon and erosion of the morning cold pool, boundary-layer dewpoints in the low-mid 70s will contribute to MLCAPE in excess of 2000 J/kg east of the surface low and south of the warm front in IA. Renewed thunderstorm development is probable by mid afternoon near the surface low, with storms expected to subsequently move/develop east-southeastward along the warm front into IL by this evening. The initial storms will likely be supercells capable of producing tornadoes and damaging winds, given the enhanced low-level shear/hodograph curvature near the cyclone/warm front, along the north edge of the unstable warm sector. Upscale growth into a cluster is expected by this evening from southeast IA/northeast MO into northwest and central IL, where damaging winds will become the more prominent threat into tonight. The MCV/cyclone will begin to move east of the surface warm sector late tonight, which should result in gradual weakening of the storms across IN. The northward extent and magnitude of the severe/tornado threat this afternoon will depend heavily on the degree of recovery from the ongoing/weakening MCS, which is still a bit uncertain. ...TX Panhandle this afternoon to southeast KS tonight... A remnant midlevel trough will drift slowly east-northeastward over the TX Panhandle today, as a weak cold front moves slowly southeastward from KS/CO. Surface heating and deep mixing will result in inverted-v profiles along and south of the front, and will support the potential for isolated strong downburst winds. Convection will tend to develop east-northeastward tonight along the front, with strong downdrafts still possible in an environment of lingering large CAPE/DCAPE. ...Maine this afternoon... A midlevel trough over James Bay will pivot east-southeastward to Maine overnight. In advance of this trough, a weak pre-frontal trough at the surface and band of weak ascent will provide a focus for thunderstorm development this afternoon. Though moisture and lapse rates will be modest, increasing deep-layer westerly shear and surface heating on the south edge of the thicker clouds could support storms capable of producing isolated damaging gusts. ...Dakotas this afternoon/evening... Widespread clouds and rain are spreading slowly eastward across the eastern Dakotas in association with a couple of diffuse MCVs from overnight convection. A little clearing of clouds and surface heating will be possible from west to east this afternoon, in advance of a larger-scale trough moving east-southeastward from MT to ND. Isolated thunderstorm development and a low-end severe threat will be possible this afternoon if sufficient near-surface destabilization occurs, given enough vertical shear for organized storms. ..Thompson/Kerr.. 08/12/2019 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0746 AM CDT Mon Aug 12 2019 Valid 121300Z - 131200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON/EVENING FROM SOUTHEAST IA INTO CENTRAL IL... ...SUMMARY... Severe thunderstorms are likely today over the middle Mississippi Valley to the Ohio Valley. Damaging gusts are the primary risk but a few tornadoes are possible. ...IA/IL this afternoon/evening... A well-defined MCV is moving eastward over western IA this morning, per reflectivity mosaics and VWP observations of 50-60 kt midlevel flow at OAX/DMX. The associated MCS and low-level cold pool have weakened since 09z, though convective outflow appears to extend farther south into KS/MO than most model guidance. Thus, recovery of the boundary layer into IA is a primary concern for this afternoon. Assuming surface heating in cloud breaks by early-mid afternoon and erosion of the morning cold pool, boundary-layer dewpoints in the low-mid 70s will contribute to MLCAPE in excess of 2000 J/kg east of the surface low and south of the warm front in IA. Renewed thunderstorm development is probable by mid afternoon near the surface low, with storms expected to subsequently move/develop east-southeastward along the warm front into IL by this evening. The initial storms will likely be supercells capable of producing tornadoes and damaging winds, given the enhanced low-level shear/hodograph curvature near the cyclone/warm front, along the north edge of the unstable warm sector. Upscale growth into a cluster is expected by this evening from southeast IA/northeast MO into northwest and central IL, where damaging winds will become the more prominent threat into tonight. The MCV/cyclone will begin to move east of the surface warm sector late tonight, which should result in gradual weakening of the storms across IN. The northward extent and magnitude of the severe/tornado threat this afternoon will depend heavily on the degree of recovery from the ongoing/weakening MCS, which is still a bit uncertain. ...TX Panhandle this afternoon to southeast KS tonight... A remnant midlevel trough will drift slowly east-northeastward over the TX Panhandle today, as a weak cold front moves slowly southeastward from KS/CO. Surface heating and deep mixing will result in inverted-v profiles along and south of the front, and will support the potential for isolated strong downburst winds. Convection will tend to develop east-northeastward tonight along the front, with strong downdrafts still possible in an environment of lingering large CAPE/DCAPE. ...Maine this afternoon... A midlevel trough over James Bay will pivot east-southeastward to Maine overnight. In advance of this trough, a weak pre-frontal trough at the surface and band of weak ascent will provide a focus for thunderstorm development this afternoon. Though moisture and lapse rates will be modest, increasing deep-layer westerly shear and surface heating on the south edge of the thicker clouds could support storms capable of producing isolated damaging gusts. ...Dakotas this afternoon/evening... Widespread clouds and rain are spreading slowly eastward across the eastern Dakotas in association with a couple of diffuse MCVs from overnight convection. A little clearing of clouds and surface heating will be possible from west to east this afternoon, in advance of a larger-scale trough moving east-southeastward from MT to ND. Isolated thunderstorm development and a low-end severe threat will be possible this afternoon if sufficient near-surface destabilization occurs, given enough vertical shear for organized storms. ..Thompson/Kerr.. 08/12/2019 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0746 AM CDT Mon Aug 12 2019 Valid 121300Z - 131200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON/EVENING FROM SOUTHEAST IA INTO CENTRAL IL... ...SUMMARY... Severe thunderstorms are likely today over the middle Mississippi Valley to the Ohio Valley. Damaging gusts are the primary risk but a few tornadoes are possible. ...IA/IL this afternoon/evening... A well-defined MCV is moving eastward over western IA this morning, per reflectivity mosaics and VWP observations of 50-60 kt midlevel flow at OAX/DMX. The associated MCS and low-level cold pool have weakened since 09z, though convective outflow appears to extend farther south into KS/MO than most model guidance. Thus, recovery of the boundary layer into IA is a primary concern for this afternoon. Assuming surface heating in cloud breaks by early-mid afternoon and erosion of the morning cold pool, boundary-layer dewpoints in the low-mid 70s will contribute to MLCAPE in excess of 2000 J/kg east of the surface low and south of the warm front in IA. Renewed thunderstorm development is probable by mid afternoon near the surface low, with storms expected to subsequently move/develop east-southeastward along the warm front into IL by this evening. The initial storms will likely be supercells capable of producing tornadoes and damaging winds, given the enhanced low-level shear/hodograph curvature near the cyclone/warm front, along the north edge of the unstable warm sector. Upscale growth into a cluster is expected by this evening from southeast IA/northeast MO into northwest and central IL, where damaging winds will become the more prominent threat into tonight. The MCV/cyclone will begin to move east of the surface warm sector late tonight, which should result in gradual weakening of the storms across IN. The northward extent and magnitude of the severe/tornado threat this afternoon will depend heavily on the degree of recovery from the ongoing/weakening MCS, which is still a bit uncertain. ...TX Panhandle this afternoon to southeast KS tonight... A remnant midlevel trough will drift slowly east-northeastward over the TX Panhandle today, as a weak cold front moves slowly southeastward from KS/CO. Surface heating and deep mixing will result in inverted-v profiles along and south of the front, and will support the potential for isolated strong downburst winds. Convection will tend to develop east-northeastward tonight along the front, with strong downdrafts still possible in an environment of lingering large CAPE/DCAPE. ...Maine this afternoon... A midlevel trough over James Bay will pivot east-southeastward to Maine overnight. In advance of this trough, a weak pre-frontal trough at the surface and band of weak ascent will provide a focus for thunderstorm development this afternoon. Though moisture and lapse rates will be modest, increasing deep-layer westerly shear and surface heating on the south edge of the thicker clouds could support storms capable of producing isolated damaging gusts. ...Dakotas this afternoon/evening... Widespread clouds and rain are spreading slowly eastward across the eastern Dakotas in association with a couple of diffuse MCVs from overnight convection. A little clearing of clouds and surface heating will be possible from west to east this afternoon, in advance of a larger-scale trough moving east-southeastward from MT to ND. Isolated thunderstorm development and a low-end severe threat will be possible this afternoon if sufficient near-surface destabilization occurs, given enough vertical shear for organized storms. ..Thompson/Kerr.. 08/12/2019 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0712 AM CDT Mon Aug 12 2019 Valid 131200Z - 141200Z ...NO CRITICAL AREAS... ...Synopsis... Weak, quasi-zonal mid-level flow will continue across the northern tier of the CONUS D2/Tuesday. Flow at the surface and aloft will be minimal across dry areas of the West outside of localized, terrain-favored areas. With the lack of major synoptic features traversing the West, fire weather conditions will be minimal. No highlights will be introduced for this outlook. ..Cook.. 08/12/2019 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0712 AM CDT Mon Aug 12 2019 Valid 131200Z - 141200Z ...NO CRITICAL AREAS... ...Synopsis... Weak, quasi-zonal mid-level flow will continue across the northern tier of the CONUS D2/Tuesday. Flow at the surface and aloft will be minimal across dry areas of the West outside of localized, terrain-favored areas. With the lack of major synoptic features traversing the West, fire weather conditions will be minimal. No highlights will be introduced for this outlook. ..Cook.. 08/12/2019 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0712 AM CDT Mon Aug 12 2019 Valid 131200Z - 141200Z ...NO CRITICAL AREAS... ...Synopsis... Weak, quasi-zonal mid-level flow will continue across the northern tier of the CONUS D2/Tuesday. Flow at the surface and aloft will be minimal across dry areas of the West outside of localized, terrain-favored areas. With the lack of major synoptic features traversing the West, fire weather conditions will be minimal. No highlights will be introduced for this outlook. ..Cook.. 08/12/2019 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0712 AM CDT Mon Aug 12 2019 Valid 121200Z - 131200Z ...NO CRITICAL AREAS... ...Synopsis... Fire weather concerns will be minimal today. A mid-level trough over the northern Rockies will weaken and eject, leaving behind weaker and more zonally oriented mid-level flow across the CONUS. Mid-level flow will become minimal across dry areas of the western U.S. Outside of areas of locally elevated fire weather in Wyoming and vicinity, the quiet overall pattern indicates that no highlights will be needed for this outlook. ..Cook.. 08/12/2019 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0712 AM CDT Mon Aug 12 2019 Valid 121200Z - 131200Z ...NO CRITICAL AREAS... ...Synopsis... Fire weather concerns will be minimal today. A mid-level trough over the northern Rockies will weaken and eject, leaving behind weaker and more zonally oriented mid-level flow across the CONUS. Mid-level flow will become minimal across dry areas of the western U.S. Outside of areas of locally elevated fire weather in Wyoming and vicinity, the quiet overall pattern indicates that no highlights will be needed for this outlook. ..Cook.. 08/12/2019 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0321 AM CDT Mon Aug 12 2019 Valid 151200Z - 201200Z ...DISCUSSION... Model consensus is that a low-amplitude west northwesterly flow regime with a trough in the east will reside across the northern tier states days 4-5. Upper trough will become established over the Pacific Northwest through northern Rockies days 6-7. Days 4-5 - Though predictability remains low at this range, best chance for a few severe storms will be over the central through northern Plains within a northwesterly flow regime. Here a corridor of modest low-level moisture will reside beneath steep lapse rates resulting in moderate instability. Timing of any embedded shortwave troughs and their accompanying boundaries will be difficult, but potential exists for storms to develop in this regime and spread southeast through the Plains where vertical shear and instability will be sufficient for storm organization. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0321 AM CDT Mon Aug 12 2019 Valid 151200Z - 201200Z ...DISCUSSION... Model consensus is that a low-amplitude west northwesterly flow regime with a trough in the east will reside across the northern tier states days 4-5. Upper trough will become established over the Pacific Northwest through northern Rockies days 6-7. Days 4-5 - Though predictability remains low at this range, best chance for a few severe storms will be over the central through northern Plains within a northwesterly flow regime. Here a corridor of modest low-level moisture will reside beneath steep lapse rates resulting in moderate instability. Timing of any embedded shortwave troughs and their accompanying boundaries will be difficult, but potential exists for storms to develop in this regime and spread southeast through the Plains where vertical shear and instability will be sufficient for storm organization. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0321 AM CDT Mon Aug 12 2019 Valid 151200Z - 201200Z ...DISCUSSION... Model consensus is that a low-amplitude west northwesterly flow regime with a trough in the east will reside across the northern tier states days 4-5. Upper trough will become established over the Pacific Northwest through northern Rockies days 6-7. Days 4-5 - Though predictability remains low at this range, best chance for a few severe storms will be over the central through northern Plains within a northwesterly flow regime. Here a corridor of modest low-level moisture will reside beneath steep lapse rates resulting in moderate instability. Timing of any embedded shortwave troughs and their accompanying boundaries will be difficult, but potential exists for storms to develop in this regime and spread southeast through the Plains where vertical shear and instability will be sufficient for storm organization. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0321 AM CDT Mon Aug 12 2019 Valid 151200Z - 201200Z ...DISCUSSION... Model consensus is that a low-amplitude west northwesterly flow regime with a trough in the east will reside across the northern tier states days 4-5. Upper trough will become established over the Pacific Northwest through northern Rockies days 6-7. Days 4-5 - Though predictability remains low at this range, best chance for a few severe storms will be over the central through northern Plains within a northwesterly flow regime. Here a corridor of modest low-level moisture will reside beneath steep lapse rates resulting in moderate instability. Timing of any embedded shortwave troughs and their accompanying boundaries will be difficult, but potential exists for storms to develop in this regime and spread southeast through the Plains where vertical shear and instability will be sufficient for storm organization. Read more

WW 0574 Status Updates
STATUS REPORT ON WW 574 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 10 WNW MHK TO 15 SSE BIE TO 10 SE LNK TO 10 NW LNK. ..KERR..08/12/19 ATTN...WFO...TOP...DDC...GLD...GID...ICT...OAX... STATUS REPORT FOR WS 574 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS KSC117-149-161-120940- KS . KANSAS COUNTIES INCLUDED ARE MARSHALL POTTAWATOMIE RILEY NEC097-127-131-133-147-120940- NE . NEBRASKA COUNTIES INCLUDED ARE JOHNSON NEMAHA OTOE PAWNEE RICHARDSON 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 574 SEVERE TSTM KS NE 120240Z - 121000Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 574 NWS Storm Prediction Center Norman OK 940 PM CDT Sun Aug 11 2019 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of North Central Kansas South-Central Nebraska * Effective this Sunday night and Monday morning from 940 PM until 500 AM CDT. ...THIS IS A PARTICULARLY DANGEROUS SITUATION... * Primary threats include... Widespread damaging winds expected with scattered significant gusts to 85 mph likely Scattered large hail and isolated very large hail events to 2 inches in diameter possible A couple tornadoes possible SUMMARY...A developing bow echo over northwest Kansas will move rapidly eastward overnight, posing a risk of widespread damaging wind gusts across the watch area. Large hail and a tornado or two are also possible. The severe thunderstorm watch area is approximately along and 60 statute miles north and south of a line from 40 miles northwest of Hill City KS to 15 miles south southeast of Beatrice NE. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU4). 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 571...WW 572...WW 573... AVIATION...A few severe thunderstorms with hail surface and aloft to 2 inches. Extreme turbulence and surface wind gusts to 75 knots. A few cumulonimbi with maximum tops to 600. Mean storm motion vector 26040. ...Hart Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 AM CDT Mon Aug 12 2019 Valid 141200Z - 151200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER A PORTION OF THE SOUTHEAST STATES AND CENTRAL HIGH PLAINS... ...SUMMARY... A few strong to severe storms with isolated damaging wind will be possible over the southeast states Wednesday afternoon. Isolated strong to severe storms will also be possible over a portion of the central High Plains. ...Synopsis... Trend will be for synoptic upper trough to amplify over the eastern U.S. Wednesday with subtropical high building into the southwestern states. At the start of the period a cold front will stretch from eastern NC southwest through the southeast states into central TX and this boundary will advance slowly southeast during the day. ...Southeast States... Rich low-level moisture with 70s F dewpoints will reside in pre-frontal warm sector supporting moderate to strong instability as the surface layer warms with 2000-3000 J/kg MLCAPE expected. Storms should develop within the weakly capped environment along the front by early afternoon and spread southeast. The moist warm sector will have been shunted well south of the stronger westerlies with weak winds aloft supportive of pulse and multicell storms, possibly evolving into line segments along the front. Isolated downburst winds will be the main threat through early evening. ...Central High Plains... A corridor of low 60s F dewpoints will reside over the central High Plains beneath steep lapse rates supporting 1500-2000 J/kg MLCAPE. This region will remain within a belt of moderate northwesterly winds aloft with 35-45 kt effective bulk shear. Background forcing is expected to remain weak, but isolated storms may develop over the higher terrain and spread southeast as well as along a lee trough. The environment will conditionally support a threat for supercells capable of large hail and downburst winds and have therefore introduced a MRGL risk category. If it begins to appear storm coverage will be greater than currently anticipated, then a SLGT risk might be needed in later outlooks. ..Dial.. 08/12/2019 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 AM CDT Mon Aug 12 2019 Valid 141200Z - 151200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER A PORTION OF THE SOUTHEAST STATES AND CENTRAL HIGH PLAINS... ...SUMMARY... A few strong to severe storms with isolated damaging wind will be possible over the southeast states Wednesday afternoon. Isolated strong to severe storms will also be possible over a portion of the central High Plains. ...Synopsis... Trend will be for synoptic upper trough to amplify over the eastern U.S. Wednesday with subtropical high building into the southwestern states. At the start of the period a cold front will stretch from eastern NC southwest through the southeast states into central TX and this boundary will advance slowly southeast during the day. ...Southeast States... Rich low-level moisture with 70s F dewpoints will reside in pre-frontal warm sector supporting moderate to strong instability as the surface layer warms with 2000-3000 J/kg MLCAPE expected. Storms should develop within the weakly capped environment along the front by early afternoon and spread southeast. The moist warm sector will have been shunted well south of the stronger westerlies with weak winds aloft supportive of pulse and multicell storms, possibly evolving into line segments along the front. Isolated downburst winds will be the main threat through early evening. ...Central High Plains... A corridor of low 60s F dewpoints will reside over the central High Plains beneath steep lapse rates supporting 1500-2000 J/kg MLCAPE. This region will remain within a belt of moderate northwesterly winds aloft with 35-45 kt effective bulk shear. Background forcing is expected to remain weak, but isolated storms may develop over the higher terrain and spread southeast as well as along a lee trough. The environment will conditionally support a threat for supercells capable of large hail and downburst winds and have therefore introduced a MRGL risk category. If it begins to appear storm coverage will be greater than currently anticipated, then a SLGT risk might be needed in later outlooks. ..Dial.. 08/12/2019 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 AM CDT Mon Aug 12 2019 Valid 141200Z - 151200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER A PORTION OF THE SOUTHEAST STATES AND CENTRAL HIGH PLAINS... ...SUMMARY... A few strong to severe storms with isolated damaging wind will be possible over the southeast states Wednesday afternoon. Isolated strong to severe storms will also be possible over a portion of the central High Plains. ...Synopsis... Trend will be for synoptic upper trough to amplify over the eastern U.S. Wednesday with subtropical high building into the southwestern states. At the start of the period a cold front will stretch from eastern NC southwest through the southeast states into central TX and this boundary will advance slowly southeast during the day. ...Southeast States... Rich low-level moisture with 70s F dewpoints will reside in pre-frontal warm sector supporting moderate to strong instability as the surface layer warms with 2000-3000 J/kg MLCAPE expected. Storms should develop within the weakly capped environment along the front by early afternoon and spread southeast. The moist warm sector will have been shunted well south of the stronger westerlies with weak winds aloft supportive of pulse and multicell storms, possibly evolving into line segments along the front. Isolated downburst winds will be the main threat through early evening. ...Central High Plains... A corridor of low 60s F dewpoints will reside over the central High Plains beneath steep lapse rates supporting 1500-2000 J/kg MLCAPE. This region will remain within a belt of moderate northwesterly winds aloft with 35-45 kt effective bulk shear. Background forcing is expected to remain weak, but isolated storms may develop over the higher terrain and spread southeast as well as along a lee trough. The environment will conditionally support a threat for supercells capable of large hail and downburst winds and have therefore introduced a MRGL risk category. If it begins to appear storm coverage will be greater than currently anticipated, then a SLGT risk might be needed in later outlooks. ..Dial.. 08/12/2019 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 AM CDT Mon Aug 12 2019 Valid 141200Z - 151200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER A PORTION OF THE SOUTHEAST STATES AND CENTRAL HIGH PLAINS... ...SUMMARY... A few strong to severe storms with isolated damaging wind will be possible over the southeast states Wednesday afternoon. Isolated strong to severe storms will also be possible over a portion of the central High Plains. ...Synopsis... Trend will be for synoptic upper trough to amplify over the eastern U.S. Wednesday with subtropical high building into the southwestern states. At the start of the period a cold front will stretch from eastern NC southwest through the southeast states into central TX and this boundary will advance slowly southeast during the day. ...Southeast States... Rich low-level moisture with 70s F dewpoints will reside in pre-frontal warm sector supporting moderate to strong instability as the surface layer warms with 2000-3000 J/kg MLCAPE expected. Storms should develop within the weakly capped environment along the front by early afternoon and spread southeast. The moist warm sector will have been shunted well south of the stronger westerlies with weak winds aloft supportive of pulse and multicell storms, possibly evolving into line segments along the front. Isolated downburst winds will be the main threat through early evening. ...Central High Plains... A corridor of low 60s F dewpoints will reside over the central High Plains beneath steep lapse rates supporting 1500-2000 J/kg MLCAPE. This region will remain within a belt of moderate northwesterly winds aloft with 35-45 kt effective bulk shear. Background forcing is expected to remain weak, but isolated storms may develop over the higher terrain and spread southeast as well as along a lee trough. The environment will conditionally support a threat for supercells capable of large hail and downburst winds and have therefore introduced a MRGL risk category. If it begins to appear storm coverage will be greater than currently anticipated, then a SLGT risk might be needed in later outlooks. ..Dial.. 08/12/2019 Read more

WW 0574 Status Updates
STATUS REPORT ON WW 574 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 25 NE RSL TO 35 SSE HSI TO 25 SE HSI TO 30 SSW EAR TO 20 W EAR. ..KERR..08/12/19 ATTN...WFO...TOP...DDC...GLD...GID...ICT...OAX... STATUS REPORT FOR WS 574 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS KSC027-029-089-105-123-143-157-201-120740- KS . KANSAS COUNTIES INCLUDED ARE CLAY CLOUD JEWELL LINCOLN MITCHELL OTTAWA REPUBLIC WASHINGTON NEC001-019-035-059-067-079-081-093-095-099-109-121-129-143-151- 159-163-169-185-120740- NE . NEBRASKA COUNTIES INCLUDED ARE ADAMS BUFFALO CLAY FILLMORE GAGE HALL HAMILTON HOWARD JEFFERSON KEARNEY LANCASTER MERRICK NUCKOLLS POLK SALINE SEWARD SHERMAN THAYER YORK Read more