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SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0249 PM CDT Tue Aug 13 2019 Valid 132000Z - 141200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL HIGH PLAINS... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE TENNESSEE VALLEY EASTWARD TO THE ATLANTIC SEABOARD... ...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. ...DISCUSSION... The main change to the outlook is to reorient the enhanced risk area in the central High Plains. The enhanced has been shifted eastward and now goes from southwest Nebraska and far northeastern Colorado into southwest Kansas which is aligned with the projected track of ongoing severe thunderstorms. The hail and wind damage probabilities have been changed according to the updated position of the enhanced risk area. Severe weather probabilities have been removed from parts of the central and northern High Plains to the north and northeast of the ongoing convection. ..Broyles.. 08/13/2019 .PREV DISCUSSION... /ISSUED 1129 AM CDT Tue Aug 13 2019/ ...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. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0249 PM CDT Tue Aug 13 2019 Valid 132000Z - 141200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL HIGH PLAINS... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE TENNESSEE VALLEY EASTWARD TO THE ATLANTIC SEABOARD... ...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. ...DISCUSSION... The main change to the outlook is to reorient the enhanced risk area in the central High Plains. The enhanced has been shifted eastward and now goes from southwest Nebraska and far northeastern Colorado into southwest Kansas which is aligned with the projected track of ongoing severe thunderstorms. The hail and wind damage probabilities have been changed according to the updated position of the enhanced risk area. Severe weather probabilities have been removed from parts of the central and northern High Plains to the north and northeast of the ongoing convection. ..Broyles.. 08/13/2019 .PREV DISCUSSION... /ISSUED 1129 AM CDT Tue Aug 13 2019/ ...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. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0249 PM CDT Tue Aug 13 2019 Valid 132000Z - 141200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL HIGH PLAINS... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE TENNESSEE VALLEY EASTWARD TO THE ATLANTIC SEABOARD... ...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. ...DISCUSSION... The main change to the outlook is to reorient the enhanced risk area in the central High Plains. The enhanced has been shifted eastward and now goes from southwest Nebraska and far northeastern Colorado into southwest Kansas which is aligned with the projected track of ongoing severe thunderstorms. The hail and wind damage probabilities have been changed according to the updated position of the enhanced risk area. Severe weather probabilities have been removed from parts of the central and northern High Plains to the north and northeast of the ongoing convection. ..Broyles.. 08/13/2019 .PREV DISCUSSION... /ISSUED 1129 AM CDT Tue Aug 13 2019/ ...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. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0249 PM CDT Tue Aug 13 2019 Valid 132000Z - 141200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL HIGH PLAINS... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE TENNESSEE VALLEY EASTWARD TO THE ATLANTIC SEABOARD... ...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. ...DISCUSSION... The main change to the outlook is to reorient the enhanced risk area in the central High Plains. The enhanced has been shifted eastward and now goes from southwest Nebraska and far northeastern Colorado into southwest Kansas which is aligned with the projected track of ongoing severe thunderstorms. The hail and wind damage probabilities have been changed according to the updated position of the enhanced risk area. Severe weather probabilities have been removed from parts of the central and northern High Plains to the north and northeast of the ongoing convection. ..Broyles.. 08/13/2019 .PREV DISCUSSION... /ISSUED 1129 AM CDT Tue Aug 13 2019/ ...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. Read more

WW 0579 Status Updates
STATUS FOR WATCH 0579 HAS NOT BEEN ISSUED YET Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0224 PM CDT Tue Aug 13 2019 Valid 141200Z - 151200Z ...NO CRITICAL AREAS... As modest flow aloft overspreads a well-mixed boundary layer, locally elevated surface wind/RH conditions may occur across terrain favoring areas from the Snake River Plain in eastern Idaho, to the Great Divide basin in central/southern Wyoming. The localized nature of the elevated conditions precludes a delineation at this time. Otherwise, the previous forecast remains on track (see below for more details). ..Squitieri.. 08/13/2019 .PREV DISCUSSION... /ISSUED 1208 AM CDT Tue Aug 13 2019/ ...Synopsis... The mid/upper synoptic pattern will amplify slightly as a broad trough becomes established across the East and a weak ridge increases across the Southwest. Stronger flow aloft will remain displaced from dry areas across the West (where fuels are cured), and this should keep fire weather concerns minimal throughout the forecast period. ...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 0224 PM CDT Tue Aug 13 2019 Valid 141200Z - 151200Z ...NO CRITICAL AREAS... As modest flow aloft overspreads a well-mixed boundary layer, locally elevated surface wind/RH conditions may occur across terrain favoring areas from the Snake River Plain in eastern Idaho, to the Great Divide basin in central/southern Wyoming. The localized nature of the elevated conditions precludes a delineation at this time. Otherwise, the previous forecast remains on track (see below for more details). ..Squitieri.. 08/13/2019 .PREV DISCUSSION... /ISSUED 1208 AM CDT Tue Aug 13 2019/ ...Synopsis... The mid/upper synoptic pattern will amplify slightly as a broad trough becomes established across the East and a weak ridge increases across the Southwest. Stronger flow aloft will remain displaced from dry areas across the West (where fuels are cured), and this should keep fire weather concerns minimal throughout the forecast period. ...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 0224 PM CDT Tue Aug 13 2019 Valid 141200Z - 151200Z ...NO CRITICAL AREAS... As modest flow aloft overspreads a well-mixed boundary layer, locally elevated surface wind/RH conditions may occur across terrain favoring areas from the Snake River Plain in eastern Idaho, to the Great Divide basin in central/southern Wyoming. The localized nature of the elevated conditions precludes a delineation at this time. Otherwise, the previous forecast remains on track (see below for more details). ..Squitieri.. 08/13/2019 .PREV DISCUSSION... /ISSUED 1208 AM CDT Tue Aug 13 2019/ ...Synopsis... The mid/upper synoptic pattern will amplify slightly as a broad trough becomes established across the East and a weak ridge increases across the Southwest. Stronger flow aloft will remain displaced from dry areas across the West (where fuels are cured), and this should keep fire weather concerns minimal throughout the forecast period. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

5-Day Uncertainty Track last updated Tue, 13 Aug 2019 19:25:26 GMT


Wind Speed Probabilities last updated Tue, 13 Aug 2019 19:25:26 GMT

WW 0578 Status Updates
STATUS FOR WATCH 0578 HAS NOT BEEN ISSUED YET Read more

MD 1725 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR PORTIONS OF MIDDLE/EASTERN TN
Mesoscale Discussion 1725 NWS Storm Prediction Center Norman OK 0158 PM CDT Tue Aug 13 2019 Areas affected...Portions of middle/eastern TN Concerning...Severe potential...Watch possible Valid 131858Z - 132100Z Probability of Watch Issuance...40 percent SUMMARY...An isolated damaging wind and large hail threat may increase this afternoon. Watch issuance is possible. DISCUSSION...Substantial destabilization has occurred this afternoon along/south of an outflow boundary extending northwest-southeast across middle/eastern TN. Isolated thunderstorms have persisted for the past couple of hours along this boundary about 50-55 miles south-southeast of Nashville TN. Additional convective development appears likely across middle/eastern TN this afternoon as modest ascent associated with a weak vorticity maximum over KY overspreads this region. MLCAPE of 2000-3500 J/kg will support robust updraft accelerations, and the potential for isolated damaging winds with convective downdrafts will exist as storms move generally east-southeastward. Marginally severe hail may also occur given the strong instability present. Primary uncertainty regarding a greater severe weather threat is the strength of mid-level winds and related potential for storm organization. Somewhat stronger westerly flow is being estimated by VWPs across KY compared to TN, but around 30-35 kt is present around 3-4 km AGL in the KHPX and KOHX VWPs. This may be enough to encourage some clustering of cells, with a small bowing line segment possibly developing with southeastward extent in parts of middle/eastern TN. Watch issuance may be needed later this afternoon (by 21Z/4 PM CDT). ..Gleason/Grams.. 08/13/2019 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...MRX...OHX...HUN...MEG... LAT...LON 36188789 36618702 36628593 36438488 36248449 35758479 35358520 35018585 35048811 35328826 35818819 36188789 Read more

WW 0576 Status Updates
STATUS REPORT ON WW 576 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 50 SSW TYS TO 30 SE TRI TO 45 E TRI TO 40 NNW AVC. ..GLEASON..08/13/19 ATTN...WFO...GSP...RAH...RNK...MRX... STATUS REPORT FOR WS 576 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS GAC241-131940- GA . GEORGIA COUNTIES INCLUDED ARE RABUN NCC001-003-005-009-011-021-023-025-027-033-035-039-043-045-057- 059-067-071-075-081-087-089-097-099-109-111-113-115-119-121-145- 149-151-157-159-161-169-171-173-175-189-193-197-199-131940- NC . NORTH CAROLINA COUNTIES INCLUDED ARE ALAMANCE ALEXANDER ALLEGHANY ASHE AVERY BUNCOMBE BURKE CABARRUS CALDWELL CASWELL CATAWBA CHEROKEE CLAY CLEVELAND DAVIDSON DAVIE FORSYTH GASTON GRAHAM GUILFORD HAYWOOD HENDERSON IREDELL JACKSON LINCOLN MCDOWELL MACON MADISON MECKLENBURG MITCHELL Read more

5-Day Uncertainty Track last updated Tue, 13 Aug 2019 18:29:56 GMT


Wind Speed Probabilities last updated Tue, 13 Aug 2019 18:29:56 GMT

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

000
ABPZ20 KNHC 131730
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 AM PDT Tue Aug 13 2019

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

The National Hurricane Center has issued its last advisory on
Henriette, which has become a remnant low located a few hundred
miles west-southwest of the southern tip of the Baja California
Peninsula.

Disorganized showers and thunderstorms located about 1100 miles
southwest of the southern tip of the Baja California peninsula are
associated with an elongated trough of low pressure. Environmental
conditions are forecast to be conducive for some development during
the next few days, and a tropical depression could form later this
week while the system moves west-northwestward at 10 to 15 mph.
* Formation chance through 48 hours...medium...40 percent.
* Formation chance through 5 days...medium...60 percent.

A broad area of low pressure is forecast to form south or
southeast of the southeastern coast of Mexico late this week.
Environmental conditions are expected to be conducive for gradual
development of the system over the weekend.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 5 days...low...30 percent.

$$
Forecaster Pasch

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