Severe Storms

MD 1724 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR PORTIONS OF SOUTH-CENTRAL INTO SOUTHEASTERN VA...CENTRAL/EASTERN NC...AND FAR NORTHERN SC
Mesoscale Discussion 1724 NWS Storm Prediction Center Norman OK 0102 PM CDT Tue Aug 13 2019 Areas affected...Portions of south-central into southeastern VA...central/eastern NC...and far northern SC Concerning...Severe potential...Watch possible Valid 131802Z - 132030Z Probability of Watch Issuance...40 percent SUMMARY...Some increase in a strong to locally damaging wind threat should occur this afternoon. Watch issuance is possible. DISCUSSION...Morning cloudiness and precipitation has hampered destabilization so far this afternoon across southeastern VA. Stronger instability is present across central NC where ample diurnal heating of a very moist low-level airmass is contributing to 1500-2500 J/kg of MLCAPE. A line of storms along the TN/NC border at 18Z should continue eastward this afternoon, eventually reaching south-central VA into central NC. Additional storm development may occur ahead of this line across parts of central NC in a weak low-level convergence zone based on latest observational and short-term model trends. Relatively stronger low to mid-level westerly flow is being estimated by KAKQ VWP in southeastern VA compared to KRAX in central NC. Related effective shear magnitudes are forecast to remain marginal across these areas through the afternoon, likely no greater than 20-30 kt. Clustering of storms into one or more loosely organized lines is possible, but is by no means certain. Strong to locally damaging downdraft winds would be the main threat given steepening low-level lapse rates. Watch issuance is possible at some point this afternoon depending on observational trends. ..Gleason/Grams.. 08/13/2019 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...AKQ...MHX...RAH...ILM...CAE... LAT...LON 34948020 36567851 37217837 37867641 37927536 36667588 35627728 34927826 34707889 34567977 34948020 Read more

WW 0577 Status Updates
STATUS FOR WATCH 0577 HAS NOT BEEN ISSUED YET Read more

WW 0577 Status Updates
STATUS FOR WATCH 0577 HAS NOT BEEN ISSUED YET Read more

MD 1723 CONCERNING SEVERE POTENTIAL...WATCH LIKELY FOR SOUTHERN NE PANHANDLE/SOUTHWEST NE...NORTHEAST CO...FAR NORTHWEST KS
Mesoscale Discussion 1723 NWS Storm Prediction Center Norman OK 1232 PM CDT Tue Aug 13 2019 Areas affected...Southern NE Panhandle/Southwest NE...Northeast CO...Far Northwest KS Concerning...Severe potential...Watch likely Valid 131732Z - 131930Z Probability of Watch Issuance...95 percent SUMMARY...Increasing thunderstorm coverage is expected over the next few hours. These storms could pose for all severe hazards and a watch will likely be needed soon. DISCUSSION...Recent surface observations reveal a low across northeast CO with southeasterly upslope flow southeast of this low across southwest NE and northwest KS. Dewpoints are generally in the mid to upper 60s and mesoanalysis estimates MLCAPE is around 2000 J/kg with little remaining MLCIN. So far, sustained convection has only developed within the storm over Garden County NE, but the expectation is for continued surface convergence and further air mass destabilization to result in increased thunderstorm coverage, mainly over the southern NE Panhandle and northeast CO. This region is on the southern edge of the better flow aloft but given the southeasterly low-level flow, the modest mid-level westerly flow is still sufficient to produce effective bulk shear around 40 kt and a supercell wind profile. An initial discrete supercell mode is anticipated with upscale growth then possible as cold pool amalgamate. Very large hail is primary threat with the initially discrete storms. A tornado or two and strong wind gusts are also possible. The primary threat will then likely transition to strong wind gusts as storms become more linear and forward propagating. ..Mosier/Grams.. 08/13/2019 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LBF...GLD...BOU...CYS... LAT...LON 40980365 41790337 41810208 41080135 39990105 39300234 39770321 40980365 Read more

WW 0576 Status Updates
STATUS FOR WATCH 0576 HAS NOT BEEN ISSUED YET Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1206 PM CDT Tue Aug 13 2019 Valid 141200Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL HIGH PLAINS... ...SUMMARY... Scattered strong to severe storms with damaging hail and wind will be possible over the central High Plains Wednesday afternoon and evening, with isolated severe wind gusts from parts of the Gulf Coast to the eastern Carolinas. ...Central High Plains... A west-northwesterly mid-level flow pattern will be in place across the High Plains on Wednesday. At the surface, a low will deepen during the day in eastern Colorado. As surface temperatures warm, a pocket of moderate instability may develop in far northeastern Colorado. Convection is expected to initiate along the front range by early afternoon. Thunderstorms should then develop and move southeastward into the central High Plains. In addition to the instability, NAM forecast soundings in far northeastern Colorado have moderate deep-layer shear mainly due to speed shear in 700 mb to 300 mb layer. This combined with steep lapse rates should be favorable for supercells and isolated large hail. Damaging wind gusts will also be possible especially as the storms move eastward away from the mountains into increasing low-level moisture and stronger instability. An isolated severe threat may continue through part of the overnight period as a shortwave trough moves southeastward and approaches the central High Plains. ...Southeast/Carolinas... A low-amplitude cyclonic mid-level flow pattern will be in place across the eastern third of the nation. At the surface, a cold front is forecast to advance into the western Carolinas and central Gulf Coast states on Wednesday. The airmass ahead of the front will be very moist with surface dewpoints in the lower to mid 70s F. In response, moderate instability is expected to develop by afternoon along and south of the front. Scattered convection should initiate along the front and move eastward along the northern edge of the stronger instability. In spite of the moisture and instability, deep-layer shear will be weak. This will make conditions favorable for isolated marginally severe wind gusts mainly as low-level lapse rates peak in the late afternoon. ...MAXIMUM RISK BY HAZARD... Tornado: 2% - Marginal Wind: 15% - Slight Hail: 15% - Slight ..Broyles.. 08/13/2019 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1206 PM CDT Tue Aug 13 2019 Valid 141200Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL HIGH PLAINS... ...SUMMARY... Scattered strong to severe storms with damaging hail and wind will be possible over the central High Plains Wednesday afternoon and evening, with isolated severe wind gusts from parts of the Gulf Coast to the eastern Carolinas. ...Central High Plains... A west-northwesterly mid-level flow pattern will be in place across the High Plains on Wednesday. At the surface, a low will deepen during the day in eastern Colorado. As surface temperatures warm, a pocket of moderate instability may develop in far northeastern Colorado. Convection is expected to initiate along the front range by early afternoon. Thunderstorms should then develop and move southeastward into the central High Plains. In addition to the instability, NAM forecast soundings in far northeastern Colorado have moderate deep-layer shear mainly due to speed shear in 700 mb to 300 mb layer. This combined with steep lapse rates should be favorable for supercells and isolated large hail. Damaging wind gusts will also be possible especially as the storms move eastward away from the mountains into increasing low-level moisture and stronger instability. An isolated severe threat may continue through part of the overnight period as a shortwave trough moves southeastward and approaches the central High Plains. ...Southeast/Carolinas... A low-amplitude cyclonic mid-level flow pattern will be in place across the eastern third of the nation. At the surface, a cold front is forecast to advance into the western Carolinas and central Gulf Coast states on Wednesday. The airmass ahead of the front will be very moist with surface dewpoints in the lower to mid 70s F. In response, moderate instability is expected to develop by afternoon along and south of the front. Scattered convection should initiate along the front and move eastward along the northern edge of the stronger instability. In spite of the moisture and instability, deep-layer shear will be weak. This will make conditions favorable for isolated marginally severe wind gusts mainly as low-level lapse rates peak in the late afternoon. ...MAXIMUM RISK BY HAZARD... Tornado: 2% - Marginal Wind: 15% - Slight Hail: 15% - Slight ..Broyles.. 08/13/2019 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1206 PM CDT Tue Aug 13 2019 Valid 141200Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL HIGH PLAINS... ...SUMMARY... Scattered strong to severe storms with damaging hail and wind will be possible over the central High Plains Wednesday afternoon and evening, with isolated severe wind gusts from parts of the Gulf Coast to the eastern Carolinas. ...Central High Plains... A west-northwesterly mid-level flow pattern will be in place across the High Plains on Wednesday. At the surface, a low will deepen during the day in eastern Colorado. As surface temperatures warm, a pocket of moderate instability may develop in far northeastern Colorado. Convection is expected to initiate along the front range by early afternoon. Thunderstorms should then develop and move southeastward into the central High Plains. In addition to the instability, NAM forecast soundings in far northeastern Colorado have moderate deep-layer shear mainly due to speed shear in 700 mb to 300 mb layer. This combined with steep lapse rates should be favorable for supercells and isolated large hail. Damaging wind gusts will also be possible especially as the storms move eastward away from the mountains into increasing low-level moisture and stronger instability. An isolated severe threat may continue through part of the overnight period as a shortwave trough moves southeastward and approaches the central High Plains. ...Southeast/Carolinas... A low-amplitude cyclonic mid-level flow pattern will be in place across the eastern third of the nation. At the surface, a cold front is forecast to advance into the western Carolinas and central Gulf Coast states on Wednesday. The airmass ahead of the front will be very moist with surface dewpoints in the lower to mid 70s F. In response, moderate instability is expected to develop by afternoon along and south of the front. Scattered convection should initiate along the front and move eastward along the northern edge of the stronger instability. In spite of the moisture and instability, deep-layer shear will be weak. This will make conditions favorable for isolated marginally severe wind gusts mainly as low-level lapse rates peak in the late afternoon. ...MAXIMUM RISK BY HAZARD... Tornado: 2% - Marginal Wind: 15% - Slight Hail: 15% - Slight ..Broyles.. 08/13/2019 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1206 PM CDT Tue Aug 13 2019 Valid 141200Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL HIGH PLAINS... ...SUMMARY... Scattered strong to severe storms with damaging hail and wind will be possible over the central High Plains Wednesday afternoon and evening, with isolated severe wind gusts from parts of the Gulf Coast to the eastern Carolinas. ...Central High Plains... A west-northwesterly mid-level flow pattern will be in place across the High Plains on Wednesday. At the surface, a low will deepen during the day in eastern Colorado. As surface temperatures warm, a pocket of moderate instability may develop in far northeastern Colorado. Convection is expected to initiate along the front range by early afternoon. Thunderstorms should then develop and move southeastward into the central High Plains. In addition to the instability, NAM forecast soundings in far northeastern Colorado have moderate deep-layer shear mainly due to speed shear in 700 mb to 300 mb layer. This combined with steep lapse rates should be favorable for supercells and isolated large hail. Damaging wind gusts will also be possible especially as the storms move eastward away from the mountains into increasing low-level moisture and stronger instability. An isolated severe threat may continue through part of the overnight period as a shortwave trough moves southeastward and approaches the central High Plains. ...Southeast/Carolinas... A low-amplitude cyclonic mid-level flow pattern will be in place across the eastern third of the nation. At the surface, a cold front is forecast to advance into the western Carolinas and central Gulf Coast states on Wednesday. The airmass ahead of the front will be very moist with surface dewpoints in the lower to mid 70s F. In response, moderate instability is expected to develop by afternoon along and south of the front. Scattered convection should initiate along the front and move eastward along the northern edge of the stronger instability. In spite of the moisture and instability, deep-layer shear will be weak. This will make conditions favorable for isolated marginally severe wind gusts mainly as low-level lapse rates peak in the late afternoon. ...MAXIMUM RISK BY HAZARD... Tornado: 2% - Marginal Wind: 15% - Slight Hail: 15% - Slight ..Broyles.. 08/13/2019 Read more

No watches are valid as of Tue Aug 13 17:08:02 UTC 2019.

MD 1722 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR PORTIONS OF EASTERN TN...SOUTHWESTERN/SOUTHERN VA...AND WESTERN/CENTRAL NC
Mesoscale Discussion 1722 NWS Storm Prediction Center Norman OK 1052 AM CDT Tue Aug 13 2019 Areas affected...Portions of eastern TN...southwestern/southern VA...and western/central NC Concerning...Severe potential...Watch possible Valid 131552Z - 131745Z Probability of Watch Issuance...60 percent SUMMARY...A threat for strong/gusty winds capable of producing isolated damage should increase this afternoon. Watch issuance is possible. DISCUSSION...15Z surface analysis and visible satellite imagery shows an outflow boundary from earlier convection has moved southward into middle/eastern TN and southwestern VA. Storms have recently begun to increase in coverage along this boundary as daytime heating warms the boundary layer. A high precipitable water airmass is in place along/south of this boundary across much of eastern TN into southwestern/south-central VA and western/central NC. As surface air temperatures warm into the 80s and 90s this afternoon, low-level lapse rates will likewise steepen and instability will increase. A belt of modestly enhanced mid-level flow (around 30-40 kt at 500 mb) will overlie this region through peak diurnal heating, with area VWPs showing the strongest winds over southern VA gradually weakening into TN/NC. Strong/gusty winds may occur as this enhanced flow aloft reaches the surface through convective downdraft processes. Isolated damage from these winds will be possible given the potential for some multicell clustering as storms spread eastward through the early evening. Watch issuance may be needed within the next couple of hours (by 18Z/Noon EDT). ..Gleason/Grams.. 08/13/2019 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...RAH...RNK...RLX...GSP...MRX... LAT...LON 37357942 37117863 36277891 35777954 35198053 35218237 35168316 35188427 35268495 35648503 37058245 37188164 37298031 37357942 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1129 AM CDT Tue Aug 13 2019 Valid 131630Z - 141200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS EASTERN CO AND WESTERN KS... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS SOUTHERN VA TO NORTHERN SC WEST ACROSS THE TN VALLEY... ...SUMMARY... Significant severe hail and wind gusts are possible across the central High Plains during the late afternoon to mid evening. Scattered damaging winds are possible from the Tennessee Valley to the Carolinas and southern Virginia through early evening. ...Central High Plains... Weak warm-advection driven convection is ongoing across northwest/north-central NE. To its south, ample low-level moisture is prevalent. The difference between the NAM/RAP in the degree of boundary-layer mixing within the warm/moist sector is unusual in that the NAM is actually quite a bit more mixed at peak heating than the RAP (typically its the reverse). Surface dew points will probably mix to 60-65 F, contributing to a confined corridor of MLCAPE of 2000-3000 J/kg across the CO/KS/NE border area beneath rather steep mid-level lapse rates. Surface-based storm development is expected around 21Z near this tri-state region as convergence strengthens at the intersection of the lee trough and the southward-sagging cold front. Initial storms will likely be discrete supercells capable of producing isolated very large hail and perhaps a tornado or two. Convection should grow upscale into a southward propagating cluster into a weak nocturnal low-level jet across far eastern CO/western KS, with a continuing threat for severe wind gusts into early tonight. ...TN Valley to the Carolinas/southern VA... A separated belt of enhanced 700-mb westerlies should remain centered on the KY to VA area through early evening. Areas of decaying stratiform rain remnants of early morning MCSs are generally located within this belt of stronger flow, largely south of 12Z HREF members. Convection is ongoing an arc across eastern TN into far southwest VA along the remnant outflow. Ample heating is occurring downstream across the Carolinas and it is possible that this convection intensifies (see MCD 1722). With flow weakening with southern extent, the degree of organization becomes increasingly uncertain, but at least a few multicell clusters should develop with a risk for scattered damaging winds across southern Virginia and parts of the Carolinas. Additional clusters should also form west across the TN Valley along the remnant outflow towards late afternoon as large buoyancy develops amid upper 70s surface dew points. Somewhat weaker effective shear from 15-25 kt should foster multicell clusters with a risk for isolated to scattered damaging winds. ...Upper MS Valley... A shortwave trough along the Red River Valley should dampen as it tracks into WI tonight. Ascent preceding this trough will coincide with a pocket of stronger surface heating and low-level convergence along a weak northwest-southeast oriented front, which will support scattered thunderstorm development towards late afternoon. A confined corridor of MLCAPE from 1000-1500 J/kg may potentially coincide with effective bulk shear near 40 kt. However, modest mid-level lapse rates should temper overall storm intensity despite the expectation of a few transient supercells. Isolated damaging winds and severe hail will likely be the main threats. A brief tornado may also occur with storms moving southeast along the boundary, where low-level shear and vertical vorticity will be larger. ..Grams/Mosier.. 08/13/2019 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1129 AM CDT Tue Aug 13 2019 Valid 131630Z - 141200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS EASTERN CO AND WESTERN KS... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS SOUTHERN VA TO NORTHERN SC WEST ACROSS THE TN VALLEY... ...SUMMARY... Significant severe hail and wind gusts are possible across the central High Plains during the late afternoon to mid evening. Scattered damaging winds are possible from the Tennessee Valley to the Carolinas and southern Virginia through early evening. ...Central High Plains... Weak warm-advection driven convection is ongoing across northwest/north-central NE. To its south, ample low-level moisture is prevalent. The difference between the NAM/RAP in the degree of boundary-layer mixing within the warm/moist sector is unusual in that the NAM is actually quite a bit more mixed at peak heating than the RAP (typically its the reverse). Surface dew points will probably mix to 60-65 F, contributing to a confined corridor of MLCAPE of 2000-3000 J/kg across the CO/KS/NE border area beneath rather steep mid-level lapse rates. Surface-based storm development is expected around 21Z near this tri-state region as convergence strengthens at the intersection of the lee trough and the southward-sagging cold front. Initial storms will likely be discrete supercells capable of producing isolated very large hail and perhaps a tornado or two. Convection should grow upscale into a southward propagating cluster into a weak nocturnal low-level jet across far eastern CO/western KS, with a continuing threat for severe wind gusts into early tonight. ...TN Valley to the Carolinas/southern VA... A separated belt of enhanced 700-mb westerlies should remain centered on the KY to VA area through early evening. Areas of decaying stratiform rain remnants of early morning MCSs are generally located within this belt of stronger flow, largely south of 12Z HREF members. Convection is ongoing an arc across eastern TN into far southwest VA along the remnant outflow. Ample heating is occurring downstream across the Carolinas and it is possible that this convection intensifies (see MCD 1722). With flow weakening with southern extent, the degree of organization becomes increasingly uncertain, but at least a few multicell clusters should develop with a risk for scattered damaging winds across southern Virginia and parts of the Carolinas. Additional clusters should also form west across the TN Valley along the remnant outflow towards late afternoon as large buoyancy develops amid upper 70s surface dew points. Somewhat weaker effective shear from 15-25 kt should foster multicell clusters with a risk for isolated to scattered damaging winds. ...Upper MS Valley... A shortwave trough along the Red River Valley should dampen as it tracks into WI tonight. Ascent preceding this trough will coincide with a pocket of stronger surface heating and low-level convergence along a weak northwest-southeast oriented front, which will support scattered thunderstorm development towards late afternoon. A confined corridor of MLCAPE from 1000-1500 J/kg may potentially coincide with effective bulk shear near 40 kt. However, modest mid-level lapse rates should temper overall storm intensity despite the expectation of a few transient supercells. Isolated damaging winds and severe hail will likely be the main threats. A brief tornado may also occur with storms moving southeast along the boundary, where low-level shear and vertical vorticity will be larger. ..Grams/Mosier.. 08/13/2019 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1129 AM CDT Tue Aug 13 2019 Valid 131630Z - 141200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS EASTERN CO AND WESTERN KS... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS SOUTHERN VA TO NORTHERN SC WEST ACROSS THE TN VALLEY... ...SUMMARY... Significant severe hail and wind gusts are possible across the central High Plains during the late afternoon to mid evening. Scattered damaging winds are possible from the Tennessee Valley to the Carolinas and southern Virginia through early evening. ...Central High Plains... Weak warm-advection driven convection is ongoing across northwest/north-central NE. To its south, ample low-level moisture is prevalent. The difference between the NAM/RAP in the degree of boundary-layer mixing within the warm/moist sector is unusual in that the NAM is actually quite a bit more mixed at peak heating than the RAP (typically its the reverse). Surface dew points will probably mix to 60-65 F, contributing to a confined corridor of MLCAPE of 2000-3000 J/kg across the CO/KS/NE border area beneath rather steep mid-level lapse rates. Surface-based storm development is expected around 21Z near this tri-state region as convergence strengthens at the intersection of the lee trough and the southward-sagging cold front. Initial storms will likely be discrete supercells capable of producing isolated very large hail and perhaps a tornado or two. Convection should grow upscale into a southward propagating cluster into a weak nocturnal low-level jet across far eastern CO/western KS, with a continuing threat for severe wind gusts into early tonight. ...TN Valley to the Carolinas/southern VA... A separated belt of enhanced 700-mb westerlies should remain centered on the KY to VA area through early evening. Areas of decaying stratiform rain remnants of early morning MCSs are generally located within this belt of stronger flow, largely south of 12Z HREF members. Convection is ongoing an arc across eastern TN into far southwest VA along the remnant outflow. Ample heating is occurring downstream across the Carolinas and it is possible that this convection intensifies (see MCD 1722). With flow weakening with southern extent, the degree of organization becomes increasingly uncertain, but at least a few multicell clusters should develop with a risk for scattered damaging winds across southern Virginia and parts of the Carolinas. Additional clusters should also form west across the TN Valley along the remnant outflow towards late afternoon as large buoyancy develops amid upper 70s surface dew points. Somewhat weaker effective shear from 15-25 kt should foster multicell clusters with a risk for isolated to scattered damaging winds. ...Upper MS Valley... A shortwave trough along the Red River Valley should dampen as it tracks into WI tonight. Ascent preceding this trough will coincide with a pocket of stronger surface heating and low-level convergence along a weak northwest-southeast oriented front, which will support scattered thunderstorm development towards late afternoon. A confined corridor of MLCAPE from 1000-1500 J/kg may potentially coincide with effective bulk shear near 40 kt. However, modest mid-level lapse rates should temper overall storm intensity despite the expectation of a few transient supercells. Isolated damaging winds and severe hail will likely be the main threats. A brief tornado may also occur with storms moving southeast along the boundary, where low-level shear and vertical vorticity will be larger. ..Grams/Mosier.. 08/13/2019 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1129 AM CDT Tue Aug 13 2019 Valid 131630Z - 141200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS EASTERN CO AND WESTERN KS... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS SOUTHERN VA TO NORTHERN SC WEST ACROSS THE TN VALLEY... ...SUMMARY... Significant severe hail and wind gusts are possible across the central High Plains during the late afternoon to mid evening. Scattered damaging winds are possible from the Tennessee Valley to the Carolinas and southern Virginia through early evening. ...Central High Plains... Weak warm-advection driven convection is ongoing across northwest/north-central NE. To its south, ample low-level moisture is prevalent. The difference between the NAM/RAP in the degree of boundary-layer mixing within the warm/moist sector is unusual in that the NAM is actually quite a bit more mixed at peak heating than the RAP (typically its the reverse). Surface dew points will probably mix to 60-65 F, contributing to a confined corridor of MLCAPE of 2000-3000 J/kg across the CO/KS/NE border area beneath rather steep mid-level lapse rates. Surface-based storm development is expected around 21Z near this tri-state region as convergence strengthens at the intersection of the lee trough and the southward-sagging cold front. Initial storms will likely be discrete supercells capable of producing isolated very large hail and perhaps a tornado or two. Convection should grow upscale into a southward propagating cluster into a weak nocturnal low-level jet across far eastern CO/western KS, with a continuing threat for severe wind gusts into early tonight. ...TN Valley to the Carolinas/southern VA... A separated belt of enhanced 700-mb westerlies should remain centered on the KY to VA area through early evening. Areas of decaying stratiform rain remnants of early morning MCSs are generally located within this belt of stronger flow, largely south of 12Z HREF members. Convection is ongoing an arc across eastern TN into far southwest VA along the remnant outflow. Ample heating is occurring downstream across the Carolinas and it is possible that this convection intensifies (see MCD 1722). With flow weakening with southern extent, the degree of organization becomes increasingly uncertain, but at least a few multicell clusters should develop with a risk for scattered damaging winds across southern Virginia and parts of the Carolinas. Additional clusters should also form west across the TN Valley along the remnant outflow towards late afternoon as large buoyancy develops amid upper 70s surface dew points. Somewhat weaker effective shear from 15-25 kt should foster multicell clusters with a risk for isolated to scattered damaging winds. ...Upper MS Valley... A shortwave trough along the Red River Valley should dampen as it tracks into WI tonight. Ascent preceding this trough will coincide with a pocket of stronger surface heating and low-level convergence along a weak northwest-southeast oriented front, which will support scattered thunderstorm development towards late afternoon. A confined corridor of MLCAPE from 1000-1500 J/kg may potentially coincide with effective bulk shear near 40 kt. However, modest mid-level lapse rates should temper overall storm intensity despite the expectation of a few transient supercells. Isolated damaging winds and severe hail will likely be the main threats. A brief tornado may also occur with storms moving southeast along the boundary, where low-level shear and vertical vorticity will be larger. ..Grams/Mosier.. 08/13/2019 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1049 AM CDT Tue Aug 13 2019 Valid 131700Z - 141200Z ...NO CRITICAL AREAS... The previous forecast remains on track, with no changes or additions made. Please see below for details. ..Squitieri.. 08/13/2019 .PREV DISCUSSION... /ISSUED 1208 AM CDT Tue Aug 13 2019/ ...Synopsis... The synoptic pattern will continue to be generally unfavorable for fire weather concerns today. Weak, quasi-zonal flow aloft will extend across the northern tier of the CONUS today. Additionally, flow across dry areas of the West will remain relatively light outside of localized, terrain-favored areas. Given the minimal fire weather concerns, no highlights will be introduced for this outlook. ...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 1049 AM CDT Tue Aug 13 2019 Valid 131700Z - 141200Z ...NO CRITICAL AREAS... The previous forecast remains on track, with no changes or additions made. Please see below for details. ..Squitieri.. 08/13/2019 .PREV DISCUSSION... /ISSUED 1208 AM CDT Tue Aug 13 2019/ ...Synopsis... The synoptic pattern will continue to be generally unfavorable for fire weather concerns today. Weak, quasi-zonal flow aloft will extend across the northern tier of the CONUS today. Additionally, flow across dry areas of the West will remain relatively light outside of localized, terrain-favored areas. Given the minimal fire weather concerns, no highlights will be introduced for this outlook. ...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 1049 AM CDT Tue Aug 13 2019 Valid 131700Z - 141200Z ...NO CRITICAL AREAS... The previous forecast remains on track, with no changes or additions made. Please see below for details. ..Squitieri.. 08/13/2019 .PREV DISCUSSION... /ISSUED 1208 AM CDT Tue Aug 13 2019/ ...Synopsis... The synoptic pattern will continue to be generally unfavorable for fire weather concerns today. Weak, quasi-zonal flow aloft will extend across the northern tier of the CONUS today. Additionally, flow across dry areas of the West will remain relatively light outside of localized, terrain-favored areas. Given the minimal fire weather concerns, no highlights will be introduced for this outlook. ...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 1049 AM CDT Tue Aug 13 2019 Valid 131700Z - 141200Z ...NO CRITICAL AREAS... The previous forecast remains on track, with no changes or additions made. Please see below for details. ..Squitieri.. 08/13/2019 .PREV DISCUSSION... /ISSUED 1208 AM CDT Tue Aug 13 2019/ ...Synopsis... The synoptic pattern will continue to be generally unfavorable for fire weather concerns today. Weak, quasi-zonal flow aloft will extend across the northern tier of the CONUS today. Additionally, flow across dry areas of the West will remain relatively light outside of localized, terrain-favored areas. Given the minimal fire weather concerns, no highlights will be introduced for this outlook. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

No Mesoscale Discussions are in effect as of Tue Aug 13 15:31:03 UTC 2019.