Aggregator

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0329 AM CDT Thu Sep 05 2019 Valid 081200Z - 131200Z ...DISCUSSION... Severe potential is expected to remain low through most of the 4-8 period, but at least a modest severe threat could evolve day 5 over a portion of the central Plains. Day 4 (Sunday) - A low amplitude shortwave trough will deamplify further as it moves through the upper MS Valley, with shortwave ridging building across the central Plains. Most thunderstorms Sunday are expected to remain on cool side of a warm front from the central and northern Plains into the upper MS Valley. Other storms will likely develop across the Rockies where moisture and instability will be limited. Day 5 (Monday) - It still appears that severe potential may undergo some increase over the central Plains day 6 (Monday) in association with an ejecting shortwave trough. Antecedent conditions will be characterized by widespread storms developing along cool side of a warm front which lowers confidence in destabilization potential. However, modest destabilization may occur from southwest SD through western NE and KS in vicinity of a lee trough during the afternoon. Vertical wind profiles will become supportive of organized storms including a few supercells. Primary uncertainty at this time is evolution of morning activity which will affect afternoon thermodynamics. Day 6 (Tuesday) - Overall severe threat should remain low to modest as the shortwave trough undergoes significant weakening over the upper MS valley and weak shortwave ridging builds over the Plains. A few strong storms with gusty winds could develop along a boundary from the Midwest into the central Plains, but predictability is low at this time. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0329 AM CDT Thu Sep 05 2019 Valid 081200Z - 131200Z ...DISCUSSION... Severe potential is expected to remain low through most of the 4-8 period, but at least a modest severe threat could evolve day 5 over a portion of the central Plains. Day 4 (Sunday) - A low amplitude shortwave trough will deamplify further as it moves through the upper MS Valley, with shortwave ridging building across the central Plains. Most thunderstorms Sunday are expected to remain on cool side of a warm front from the central and northern Plains into the upper MS Valley. Other storms will likely develop across the Rockies where moisture and instability will be limited. Day 5 (Monday) - It still appears that severe potential may undergo some increase over the central Plains day 6 (Monday) in association with an ejecting shortwave trough. Antecedent conditions will be characterized by widespread storms developing along cool side of a warm front which lowers confidence in destabilization potential. However, modest destabilization may occur from southwest SD through western NE and KS in vicinity of a lee trough during the afternoon. Vertical wind profiles will become supportive of organized storms including a few supercells. Primary uncertainty at this time is evolution of morning activity which will affect afternoon thermodynamics. Day 6 (Tuesday) - Overall severe threat should remain low to modest as the shortwave trough undergoes significant weakening over the upper MS valley and weak shortwave ridging builds over the Plains. A few strong storms with gusty winds could develop along a boundary from the Midwest into the central Plains, but predictability is low at this time. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0329 AM CDT Thu Sep 05 2019 Valid 081200Z - 131200Z ...DISCUSSION... Severe potential is expected to remain low through most of the 4-8 period, but at least a modest severe threat could evolve day 5 over a portion of the central Plains. Day 4 (Sunday) - A low amplitude shortwave trough will deamplify further as it moves through the upper MS Valley, with shortwave ridging building across the central Plains. Most thunderstorms Sunday are expected to remain on cool side of a warm front from the central and northern Plains into the upper MS Valley. Other storms will likely develop across the Rockies where moisture and instability will be limited. Day 5 (Monday) - It still appears that severe potential may undergo some increase over the central Plains day 6 (Monday) in association with an ejecting shortwave trough. Antecedent conditions will be characterized by widespread storms developing along cool side of a warm front which lowers confidence in destabilization potential. However, modest destabilization may occur from southwest SD through western NE and KS in vicinity of a lee trough during the afternoon. Vertical wind profiles will become supportive of organized storms including a few supercells. Primary uncertainty at this time is evolution of morning activity which will affect afternoon thermodynamics. Day 6 (Tuesday) - Overall severe threat should remain low to modest as the shortwave trough undergoes significant weakening over the upper MS valley and weak shortwave ridging builds over the Plains. A few strong storms with gusty winds could develop along a boundary from the Midwest into the central Plains, but predictability is low at this time. Read more

WW 0635 Status Updates
STATUS REPORT ON WW 635 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 1926 ..SMITH..09/05/19 ATTN...WFO...ILM... STATUS REPORT FOR WT 635 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS NCC017-019-047-129-141-051100- NC . NORTH CAROLINA COUNTIES INCLUDED ARE BLADEN BRUNSWICK COLUMBUS NEW HANOVER PENDER SCC043-051-067-051100- SC . SOUTH CAROLINA COUNTIES INCLUDED ARE GEORGETOWN HORRY MARION AMZ250-252-254-256-270-272-274-276-051100- CW . ADJACENT COASTAL WATERS INCLUDED ARE COASTAL WATERS FROM SURF CITY TO CAPE FEAR NC OUT 20 NM Read more

WW 0635 Status Updates
STATUS REPORT ON WW 635 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 1926 ..SMITH..09/05/19 ATTN...WFO...ILM... STATUS REPORT FOR WT 635 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS NCC017-019-047-129-141-051100- NC . NORTH CAROLINA COUNTIES INCLUDED ARE BLADEN BRUNSWICK COLUMBUS NEW HANOVER PENDER SCC043-051-067-051100- SC . SOUTH CAROLINA COUNTIES INCLUDED ARE GEORGETOWN HORRY MARION AMZ250-252-254-256-270-272-274-276-051100- CW . ADJACENT COASTAL WATERS INCLUDED ARE COASTAL WATERS FROM SURF CITY TO CAPE FEAR NC OUT 20 NM Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0218 AM CDT Thu Sep 05 2019 Valid 071200Z - 081200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER A PORTION OF THE CENTRAL PLAINS... ...SUMMARY... A few strong storms with gusty winds and some hail will be possible over a portion of the central Plains region Saturday afternoon and evening. ...Central Plains... Low-amplitude shortwave trough will move east southeast through the northern and central Plains region Saturday. Saturday morning a lee trough will reside from southeast MT into the central High Plains, and this boundary will shift east into western SD and western NE during the day. A stationary front will extend from southeast MT into SD. Farther south a warm front initially across OK will move north and become situated near the KS/NE border during the evening. Modest low-level moisture with upper 50s to near 60s F dewpoints will characterize the boundary layer across western NE into northeast CO during the afternoon, and diabatic heating should boost MLCAPE to around 1500 J/kg. Belt of modest westerlies aloft with 35 kt at 500 mb will accompany the shortwave trough with 30-40 kt deep-layer shear over western NE. Stronger forcing for ascent will remain across the mountains of CO and north of warm front across the Dakotas. Most models develop little to no convection within zone of weak convergence along the lee trough across western NE. Nevertheless, isolated storms might develop in this environment with a conditional threat of a supercell or two capable of locally strong wind gusts and hail. Farther east along the warm front across northern KS, richer low-level moisture with mid to upper 60s F dewpoints will support moderate instability with 2000 J/kg MUCAPE. While isolated storms will be possible along this boundary across northern KS by late afternoon, a more likely scenario is for elevated storms to develop in southern NE on the cool side of the front overnight supported by increasing isentropic ascent on nose of a strengthening low-level jet. Isolated marginally severe hail appears to be the primary severe threat. ..Dial.. 09/05/2019 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0218 AM CDT Thu Sep 05 2019 Valid 071200Z - 081200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER A PORTION OF THE CENTRAL PLAINS... ...SUMMARY... A few strong storms with gusty winds and some hail will be possible over a portion of the central Plains region Saturday afternoon and evening. ...Central Plains... Low-amplitude shortwave trough will move east southeast through the northern and central Plains region Saturday. Saturday morning a lee trough will reside from southeast MT into the central High Plains, and this boundary will shift east into western SD and western NE during the day. A stationary front will extend from southeast MT into SD. Farther south a warm front initially across OK will move north and become situated near the KS/NE border during the evening. Modest low-level moisture with upper 50s to near 60s F dewpoints will characterize the boundary layer across western NE into northeast CO during the afternoon, and diabatic heating should boost MLCAPE to around 1500 J/kg. Belt of modest westerlies aloft with 35 kt at 500 mb will accompany the shortwave trough with 30-40 kt deep-layer shear over western NE. Stronger forcing for ascent will remain across the mountains of CO and north of warm front across the Dakotas. Most models develop little to no convection within zone of weak convergence along the lee trough across western NE. Nevertheless, isolated storms might develop in this environment with a conditional threat of a supercell or two capable of locally strong wind gusts and hail. Farther east along the warm front across northern KS, richer low-level moisture with mid to upper 60s F dewpoints will support moderate instability with 2000 J/kg MUCAPE. While isolated storms will be possible along this boundary across northern KS by late afternoon, a more likely scenario is for elevated storms to develop in southern NE on the cool side of the front overnight supported by increasing isentropic ascent on nose of a strengthening low-level jet. Isolated marginally severe hail appears to be the primary severe threat. ..Dial.. 09/05/2019 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0218 AM CDT Thu Sep 05 2019 Valid 071200Z - 081200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER A PORTION OF THE CENTRAL PLAINS... ...SUMMARY... A few strong storms with gusty winds and some hail will be possible over a portion of the central Plains region Saturday afternoon and evening. ...Central Plains... Low-amplitude shortwave trough will move east southeast through the northern and central Plains region Saturday. Saturday morning a lee trough will reside from southeast MT into the central High Plains, and this boundary will shift east into western SD and western NE during the day. A stationary front will extend from southeast MT into SD. Farther south a warm front initially across OK will move north and become situated near the KS/NE border during the evening. Modest low-level moisture with upper 50s to near 60s F dewpoints will characterize the boundary layer across western NE into northeast CO during the afternoon, and diabatic heating should boost MLCAPE to around 1500 J/kg. Belt of modest westerlies aloft with 35 kt at 500 mb will accompany the shortwave trough with 30-40 kt deep-layer shear over western NE. Stronger forcing for ascent will remain across the mountains of CO and north of warm front across the Dakotas. Most models develop little to no convection within zone of weak convergence along the lee trough across western NE. Nevertheless, isolated storms might develop in this environment with a conditional threat of a supercell or two capable of locally strong wind gusts and hail. Farther east along the warm front across northern KS, richer low-level moisture with mid to upper 60s F dewpoints will support moderate instability with 2000 J/kg MUCAPE. While isolated storms will be possible along this boundary across northern KS by late afternoon, a more likely scenario is for elevated storms to develop in southern NE on the cool side of the front overnight supported by increasing isentropic ascent on nose of a strengthening low-level jet. Isolated marginally severe hail appears to be the primary severe threat. ..Dial.. 09/05/2019 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0218 AM CDT Thu Sep 05 2019 Valid 071200Z - 081200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER A PORTION OF THE CENTRAL PLAINS... ...SUMMARY... A few strong storms with gusty winds and some hail will be possible over a portion of the central Plains region Saturday afternoon and evening. ...Central Plains... Low-amplitude shortwave trough will move east southeast through the northern and central Plains region Saturday. Saturday morning a lee trough will reside from southeast MT into the central High Plains, and this boundary will shift east into western SD and western NE during the day. A stationary front will extend from southeast MT into SD. Farther south a warm front initially across OK will move north and become situated near the KS/NE border during the evening. Modest low-level moisture with upper 50s to near 60s F dewpoints will characterize the boundary layer across western NE into northeast CO during the afternoon, and diabatic heating should boost MLCAPE to around 1500 J/kg. Belt of modest westerlies aloft with 35 kt at 500 mb will accompany the shortwave trough with 30-40 kt deep-layer shear over western NE. Stronger forcing for ascent will remain across the mountains of CO and north of warm front across the Dakotas. Most models develop little to no convection within zone of weak convergence along the lee trough across western NE. Nevertheless, isolated storms might develop in this environment with a conditional threat of a supercell or two capable of locally strong wind gusts and hail. Farther east along the warm front across northern KS, richer low-level moisture with mid to upper 60s F dewpoints will support moderate instability with 2000 J/kg MUCAPE. While isolated storms will be possible along this boundary across northern KS by late afternoon, a more likely scenario is for elevated storms to develop in southern NE on the cool side of the front overnight supported by increasing isentropic ascent on nose of a strengthening low-level jet. Isolated marginally severe hail appears to be the primary severe threat. ..Dial.. 09/05/2019 Read more

No watches are valid as of Thu Sep 5 07:20:06 UTC 2019.

MD 1926 CONCERNING SEVERE POTENTIAL...TORNADO WATCH LIKELY FOR SC GRAND STRAND AND SOUTHERN COASTAL NC
Mesoscale Discussion 1926 NWS Storm Prediction Center Norman OK 0216 AM CDT Thu Sep 05 2019 Areas affected...SC Grand Strand and southern coastal NC Concerning...Severe potential...Tornado Watch likely Valid 050716Z - 050915Z Probability of Watch Issuance...80 percent SUMMARY...A tornado watch will likely be needed before 5am EDT as supercells, located within an outer band of Hurricane Dorian, move to the near-coastal waters of Long Bay and the NC/SC coastal plain. DISCUSSION...Radar mosaic imagery shows an outer convective band arcing from near Myrtle Beach east over the Gulf Stream as Hurricane Dorian moves towards the Carolina coast. Several weak/transient circulations associated with miniature supercells have been noted within this convective band during the past 1-2 hours. The distance between the circulations and the coastline has steadily decreased with 30nm currently between the coast and the leading supercells. Subjective surface analysis places a maritime warm front arcing north and northeastward along the immediate shelf waters with surface dewpoints in the lower 70s degree F west and middle-upper 70s F east. The boundary is likely to slowly overspread the Cape Lookout and Cape Fear areas before dawn. The 06z MHX raob showed only 200 J/kg MLCAPE but was located on the relatively drier/less unstable side of the boundary. RAP forecast soundings for the coastal area of the NC/SC border indicate MLCAPE will increase into the 500-1000 J/kg over the next 1-2 hours as richer low-level moisture infiltrates the immediate coast. The KLTX VAD shows around 400 m2/s^2 0-1km SRH when inputting observed storm motions. All of the above factors will likely contribute to a risk for supercell tornadoes beginning near the coast of the NC/SC border and gradually spreading northward past Cape Fear early this morning. ..Smith/Grams.. 09/05/2019 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...MHX...ILM... LAT...LON 33537911 33887902 34577809 34627760 33857690 33167780 33207864 33537911 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0119 AM CDT Thu Sep 05 2019 Valid 061200Z - 071200Z ...NO CRITICAL AREAS... ...Synopsis... Winds will remain light across the western CONUS on Friday which will limit the overall threat for large fire spread. An upper-level trough will move from the Pacific Northwest into the northern Rockies with thunderstorm activity expected. However increasing moisture associated with this trough will lead to more wet storm modes and should limit the threat for additional fire starts. ..Bentley.. 09/05/2019 ...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 0119 AM CDT Thu Sep 05 2019 Valid 061200Z - 071200Z ...NO CRITICAL AREAS... ...Synopsis... Winds will remain light across the western CONUS on Friday which will limit the overall threat for large fire spread. An upper-level trough will move from the Pacific Northwest into the northern Rockies with thunderstorm activity expected. However increasing moisture associated with this trough will lead to more wet storm modes and should limit the threat for additional fire starts. ..Bentley.. 09/05/2019 ...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 0119 AM CDT Thu Sep 05 2019 Valid 061200Z - 071200Z ...NO CRITICAL AREAS... ...Synopsis... Winds will remain light across the western CONUS on Friday which will limit the overall threat for large fire spread. An upper-level trough will move from the Pacific Northwest into the northern Rockies with thunderstorm activity expected. However increasing moisture associated with this trough will lead to more wet storm modes and should limit the threat for additional fire starts. ..Bentley.. 09/05/2019 ...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 0119 AM CDT Thu Sep 05 2019 Valid 061200Z - 071200Z ...NO CRITICAL AREAS... ...Synopsis... Winds will remain light across the western CONUS on Friday which will limit the overall threat for large fire spread. An upper-level trough will move from the Pacific Northwest into the northern Rockies with thunderstorm activity expected. However increasing moisture associated with this trough will lead to more wet storm modes and should limit the threat for additional fire starts. ..Bentley.. 09/05/2019 ...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 0118 AM CDT Thu Sep 05 2019 Valid 051200Z - 061200Z ...Synopsis... A potent upper-level trough is moving into the Pacific Northwest this morning with numerous lightning being observed in northern California. Some of these storms are expected to continue into the morning hours today before a brief lull is likely during late morning and early afternoon. Additional thunderstorms are expected during the afternoon as surface temperatures warm. PWAT values across much of the Northwest will be in the 0.75" range which, combined with storm speeds around 30 mph, will support a threat for dry thunderstorms. Otherwise, light winds are expected across much of the dry portions in the western CONUS which will limit the threat for large fire spread. ..Bentley.. 09/05/2019 ...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 0118 AM CDT Thu Sep 05 2019 Valid 051200Z - 061200Z ...Synopsis... A potent upper-level trough is moving into the Pacific Northwest this morning with numerous lightning being observed in northern California. Some of these storms are expected to continue into the morning hours today before a brief lull is likely during late morning and early afternoon. Additional thunderstorms are expected during the afternoon as surface temperatures warm. PWAT values across much of the Northwest will be in the 0.75" range which, combined with storm speeds around 30 mph, will support a threat for dry thunderstorms. Otherwise, light winds are expected across much of the dry portions in the western CONUS which will limit the threat for large fire spread. ..Bentley.. 09/05/2019 ...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 0118 AM CDT Thu Sep 05 2019 Valid 051200Z - 061200Z ...Synopsis... A potent upper-level trough is moving into the Pacific Northwest this morning with numerous lightning being observed in northern California. Some of these storms are expected to continue into the morning hours today before a brief lull is likely during late morning and early afternoon. Additional thunderstorms are expected during the afternoon as surface temperatures warm. PWAT values across much of the Northwest will be in the 0.75" range which, combined with storm speeds around 30 mph, will support a threat for dry thunderstorms. Otherwise, light winds are expected across much of the dry portions in the western CONUS which will limit the threat for large fire spread. ..Bentley.. 09/05/2019 ...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 0118 AM CDT Thu Sep 05 2019 Valid 051200Z - 061200Z ...Synopsis... A potent upper-level trough is moving into the Pacific Northwest this morning with numerous lightning being observed in northern California. Some of these storms are expected to continue into the morning hours today before a brief lull is likely during late morning and early afternoon. Additional thunderstorms are expected during the afternoon as surface temperatures warm. PWAT values across much of the Northwest will be in the 0.75" range which, combined with storm speeds around 30 mph, will support a threat for dry thunderstorms. Otherwise, light winds are expected across much of the dry portions in the western CONUS which will limit the threat for large fire spread. ..Bentley.. 09/05/2019 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1225 AM CDT Thu Sep 05 2019 Valid 061200Z - 071200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER A PORTION OF THE NORTHERN ROCKIES... ...SUMMARY... A few thunderstorms capable of isolated strong wind gusts will be possible over a portion of the northern Rockies Friday. ...Northern Rockies region... A shortwave trough will suppress the northern periphery of an upper ridge and continue through the northern Rockies Friday. Boundary layer dewpoints generally in the 40s to low 50s F will support 500-1000 J/kg MLCAPE where sufficient heating of the surface layer occurs. Vertical wind profiles accompanying the upper trough with 30-35 kt effective bulk shear will generally promote multicells. Widely scattered high-based storms will likely develop over the mountains and spread east into a portion of the High Plains. Inverted-V thermodynamic profiles suggest few of the storms might produce locally strong wind gusts from mid afternoon through mid evening. ...North Carolina Coast... The center of Hurricane Dorian is forecast by the National Hurricane center to be over the NC outer banks early Friday, but will continue northeast away from shore during the day. Therefore, the more favorable quadrant for isolated tornadoes should remain offshore with minimal threat inland. ...MAXIMUM RISK BY HAZARD... Tornado: <2% - None Wind: 5% - Marginal Hail: <5% - None ..Dial.. 09/05/2019 Read more