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SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0255 PM CDT Wed Aug 07 2019 Valid 081200Z - 091200Z The forecast generally remains on track. The ISODRYT area has been extended into portions of northeastern Washington. Some potential exists for a storm or two to develop during the afternoon. Aside from a lightning ignition risk, a very dry boundary layer will promote gusty outflow winds from any storm. Given the potential impact to the ongoing Williams Flats fire, this extension seems prudent. Scattered coverage of storms still is possible in portions of west-central Nevada and points northward. Too much uncertainty remains as to how dry storms will be to introduce a SCTDRYT area at this time. For more details, please see the discussion below. ..Wendt.. 08/07/2019 .PREV DISCUSSION... /ISSUED 0159 AM CDT Wed Aug 07 2019/ ...Synopsis... The upper ridge across the Southwest into the Intermountain West is expected to shift slowly eastward on Thursday, as a deep upper trough approaches the Pacific Coast. Gradually increasing moisture in advance of the upper trough will continue to support at least isolated thunderstorm activity across portions of the Great Basin and interior Northwest. ...Central/northern NV into the interior Northwest... Thunderstorm coverage will likely increase compared to D1/Wednesday across central/northern NV into the interior Northwest on Thursday, as moisture gradually increases and the deep upper trough impinges on the region. Given the presence of potentially scattered thunderstorms overlapping regions of receptive fuels, lightning-related ignitions will again be possible, though there will also be greater potential for rainfall compared to D1/Wednesday. The greatest thunderstorm coverage is forecast to be over central/northern NV, but due to lingering uncertainty regarding convective evolution and potentially greater rainfall with any thunderstorm activity, the ISODRYT area is maintained in this outlook with no upgrade at this time. ...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 0255 PM CDT Wed Aug 07 2019 Valid 081200Z - 091200Z The forecast generally remains on track. The ISODRYT area has been extended into portions of northeastern Washington. Some potential exists for a storm or two to develop during the afternoon. Aside from a lightning ignition risk, a very dry boundary layer will promote gusty outflow winds from any storm. Given the potential impact to the ongoing Williams Flats fire, this extension seems prudent. Scattered coverage of storms still is possible in portions of west-central Nevada and points northward. Too much uncertainty remains as to how dry storms will be to introduce a SCTDRYT area at this time. For more details, please see the discussion below. ..Wendt.. 08/07/2019 .PREV DISCUSSION... /ISSUED 0159 AM CDT Wed Aug 07 2019/ ...Synopsis... The upper ridge across the Southwest into the Intermountain West is expected to shift slowly eastward on Thursday, as a deep upper trough approaches the Pacific Coast. Gradually increasing moisture in advance of the upper trough will continue to support at least isolated thunderstorm activity across portions of the Great Basin and interior Northwest. ...Central/northern NV into the interior Northwest... Thunderstorm coverage will likely increase compared to D1/Wednesday across central/northern NV into the interior Northwest on Thursday, as moisture gradually increases and the deep upper trough impinges on the region. Given the presence of potentially scattered thunderstorms overlapping regions of receptive fuels, lightning-related ignitions will again be possible, though there will also be greater potential for rainfall compared to D1/Wednesday. The greatest thunderstorm coverage is forecast to be over central/northern NV, but due to lingering uncertainty regarding convective evolution and potentially greater rainfall with any thunderstorm activity, the ISODRYT area is maintained in this outlook with no upgrade at this time. ...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 0255 PM CDT Wed Aug 07 2019 Valid 081200Z - 091200Z The forecast generally remains on track. The ISODRYT area has been extended into portions of northeastern Washington. Some potential exists for a storm or two to develop during the afternoon. Aside from a lightning ignition risk, a very dry boundary layer will promote gusty outflow winds from any storm. Given the potential impact to the ongoing Williams Flats fire, this extension seems prudent. Scattered coverage of storms still is possible in portions of west-central Nevada and points northward. Too much uncertainty remains as to how dry storms will be to introduce a SCTDRYT area at this time. For more details, please see the discussion below. ..Wendt.. 08/07/2019 .PREV DISCUSSION... /ISSUED 0159 AM CDT Wed Aug 07 2019/ ...Synopsis... The upper ridge across the Southwest into the Intermountain West is expected to shift slowly eastward on Thursday, as a deep upper trough approaches the Pacific Coast. Gradually increasing moisture in advance of the upper trough will continue to support at least isolated thunderstorm activity across portions of the Great Basin and interior Northwest. ...Central/northern NV into the interior Northwest... Thunderstorm coverage will likely increase compared to D1/Wednesday across central/northern NV into the interior Northwest on Thursday, as moisture gradually increases and the deep upper trough impinges on the region. Given the presence of potentially scattered thunderstorms overlapping regions of receptive fuels, lightning-related ignitions will again be possible, though there will also be greater potential for rainfall compared to D1/Wednesday. The greatest thunderstorm coverage is forecast to be over central/northern NV, but due to lingering uncertainty regarding convective evolution and potentially greater rainfall with any thunderstorm activity, the ISODRYT area is maintained in this outlook with no upgrade at this time. ...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 0255 PM CDT Wed Aug 07 2019 Valid 081200Z - 091200Z The forecast generally remains on track. The ISODRYT area has been extended into portions of northeastern Washington. Some potential exists for a storm or two to develop during the afternoon. Aside from a lightning ignition risk, a very dry boundary layer will promote gusty outflow winds from any storm. Given the potential impact to the ongoing Williams Flats fire, this extension seems prudent. Scattered coverage of storms still is possible in portions of west-central Nevada and points northward. Too much uncertainty remains as to how dry storms will be to introduce a SCTDRYT area at this time. For more details, please see the discussion below. ..Wendt.. 08/07/2019 .PREV DISCUSSION... /ISSUED 0159 AM CDT Wed Aug 07 2019/ ...Synopsis... The upper ridge across the Southwest into the Intermountain West is expected to shift slowly eastward on Thursday, as a deep upper trough approaches the Pacific Coast. Gradually increasing moisture in advance of the upper trough will continue to support at least isolated thunderstorm activity across portions of the Great Basin and interior Northwest. ...Central/northern NV into the interior Northwest... Thunderstorm coverage will likely increase compared to D1/Wednesday across central/northern NV into the interior Northwest on Thursday, as moisture gradually increases and the deep upper trough impinges on the region. Given the presence of potentially scattered thunderstorms overlapping regions of receptive fuels, lightning-related ignitions will again be possible, though there will also be greater potential for rainfall compared to D1/Wednesday. The greatest thunderstorm coverage is forecast to be over central/northern NV, but due to lingering uncertainty regarding convective evolution and potentially greater rainfall with any thunderstorm activity, the ISODRYT area is maintained in this outlook with no upgrade at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

WW 0559 Status Updates
STATUS REPORT ON WW 559 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 25 ENE FYV TO 20 NW ARG TO 15 NW POF. ..SMITH..08/07/19 ATTN...WFO...LZK...TSA...MEG...PAH...SGF... STATUS REPORT FOR WS 559 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ARC021-023-031-035-037-055-063-065-067-075-077-087-093-095-101- 107-111-117-121-123-129-135-137-141-143-145-147-072040- AR . ARKANSAS COUNTIES INCLUDED ARE CLAY CLEBURNE CRAIGHEAD CRITTENDEN CROSS GREENE INDEPENDENCE IZARD JACKSON LAWRENCE LEE MADISON MISSISSIPPI MONROE NEWTON PHILLIPS POINSETT PRAIRIE RANDOLPH ST. FRANCIS SEARCY SHARP STONE VAN BUREN WASHINGTON WHITE WOODRUFF MSC027-033-093-107-119-137-143-072040- MS . MISSISSIPPI COUNTIES INCLUDED ARE COAHOMA DESOTO MARSHALL PANOLA QUITMAN TATE TUNICA Read more

WW 0560 Status Updates
STATUS REPORT ON WW 560 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 20 WSW RDU TO 15 NW RWI TO 15 SW RIC TO 35 WSW DCA TO 20 NNW DCA TO 25 NE BWI. ..SMITH..08/07/19 ATTN...WFO...LWX...AKQ...MHX...RAH... STATUS REPORT FOR WS 560 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS DCC001-072040- DC . DISTRICT OF COLUMBIA COUNTIES INCLUDED ARE DISTRICT OF COLUMBIA MDC003-009-017-019-025-027-031-033-037-039-045-047-510-072040- MD . MARYLAND COUNTIES INCLUDED ARE ANNE ARUNDEL CALVERT CHARLES DORCHESTER HARFORD HOWARD MONTGOMERY PRINCE GEORGES ST. MARYS SOMERSET WICOMICO WORCESTER MARYLAND INDEPENDENT CITIES INCLUDED ARE BALTIMORE CITY Read more

WW 0561 Status Updates
000-072020- STATUS REPORT ON WW 561 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 25 SSE CXY TO 15 W MSV TO 15 E BGM. ..SMITH..08/07/19 ATTN...WFO...OKX...BOX...ALY...PHI...GYX...BGM...CTP...BTV... STATUS REPORT FOR WS 561 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS CTC001-003-005-007-009-011-013-015-072020- CT . CONNECTICUT COUNTIES INCLUDED ARE FAIRFIELD HARTFORD LITCHFIELD MIDDLESEX NEW HAVEN NEW LONDON TOLLAND WINDHAM DEC001-003-005-072020- DE . DELAWARE COUNTIES INCLUDED ARE KENT NEW CASTLE SUSSEX MDC011-015-029-035-041-072020- MD . MARYLAND COUNTIES INCLUDED ARE CAROLINE CECIL KENT Read more

MD 1667 CONCERNING SEVERE THUNDERSTORM WATCH 560... FOR EASTERN NORTH CAROLINA AND EASTERN VIRGINIA
Mesoscale Discussion 1667 NWS Storm Prediction Center Norman OK 0225 PM CDT Wed Aug 07 2019 Areas affected...Eastern North Carolina and eastern Virginia Concerning...Severe Thunderstorm Watch 560... Valid 071925Z - 072030Z The severe weather threat for Severe Thunderstorm Watch 560 continues. SUMMARY...The severe weather threat continues in watch 560. DISCUSSION...A cluster of storms has developed from northern North Carolina into southeast Virginia. These storms will continue to move east into an environment with around 2500 J/kg MLCAPE. Effective shear around 35-40 knots per area VWPs will continue to support storm organization. Relatively weak mid-level lapse rates should continue to limit the hail threat to only a few isolated reports. RAX and AKQ VWP show weak flow below 4 km which is likely why severe winds have also been somewhat limited up to this point. However, sub-severe damaging winds remain a threat through the afternoon and evening with an isolated threat for severe wind gusts from any stronger storms. ..Bentley.. 08/07/2019 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...AKQ...MHX...LWX...RAH... LAT...LON 35607917 36487815 37817750 38247706 38457593 38087571 36247548 35807539 34917617 34697668 34627720 34937801 35607917 Read more

WW 0560 Status Updates
STATUS REPORT ON WW 560 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..BENTLEY..08/07/19 ATTN...WFO...LWX...AKQ...MHX...RAH... STATUS REPORT FOR WS 560 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS DCC001-071940- DC . DISTRICT OF COLUMBIA COUNTIES INCLUDED ARE DISTRICT OF COLUMBIA MDC003-005-009-013-017-019-021-025-027-031-033-037-039-045-047- 510-071940- MD . MARYLAND COUNTIES INCLUDED ARE ANNE ARUNDEL BALTIMORE CALVERT CARROLL CHARLES DORCHESTER FREDERICK HARFORD HOWARD MONTGOMERY PRINCE GEORGES ST. MARYS SOMERSET WICOMICO WORCESTER MARYLAND INDEPENDENT CITIES INCLUDED ARE BALTIMORE CITY Read more

WW 0559 Status Updates
STATUS REPORT ON WW 559 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 30 NW HRO TO 20 NNE FLP TO 45 NE UNO. ..SMITH..08/07/19 ATTN...WFO...LZK...TSA...MEG...PAH...SGF... STATUS REPORT FOR WS 559 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ARC005-009-015-021-023-031-035-037-049-055-063-065-067-075-077- 087-089-093-095-101-107-111-117-121-123-129-135-137-141-143-145- 147-071920- AR . ARKANSAS COUNTIES INCLUDED ARE BAXTER BOONE CARROLL CLAY CLEBURNE CRAIGHEAD CRITTENDEN CROSS FULTON GREENE INDEPENDENCE IZARD JACKSON LAWRENCE LEE MADISON MARION MISSISSIPPI MONROE NEWTON PHILLIPS POINSETT PRAIRIE RANDOLPH ST. FRANCIS SEARCY SHARP STONE VAN BUREN WASHINGTON WHITE WOODRUFF MSC027-033-093-107-119-137-143-071920- MS . MISSISSIPPI COUNTIES INCLUDED ARE Read more

WW 0561 Status Updates
STATUS FOR WATCH 0561 HAS NOT BEEN ISSUED YET Read more

MD 1666 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR NORTHERN WISCONSIN AND THE UPPER PENINSULA OF MICHIGAN
Mesoscale Discussion 1666 NWS Storm Prediction Center Norman OK 0109 PM CDT Wed Aug 07 2019 Areas affected...Northern Wisconsin and the Upper Peninsula of Michigan Concerning...Severe potential...Watch possible Valid 071809Z - 072015Z Probability of Watch Issuance...60 percent SUMMARY...Additional storm development is expected through the afternoon/evening. A severe thunderstorm watch is possible. DISCUSSION...Storms have developed along a cold front from the eastern Upper Peninsula of Michigan westward into northern Wisconsin. The environment is only marginally favorable for severe storms at this time with MLCAPE around 500 to 1000 J/kg and effective shear around 20 to 25 knots. However, the environment will improve through across northern Wisconsin through the day as MLCAPE is expected to increase to near 2000 J/kg and mid-level flow is expected to increase from ~25 knots presently to ~40 knots by mid-evening. As the environment improves, expect storm organization and intensity to increase. The primary threats will be large hail and damaging winds. Storm trends will continue to be monitored for the next few hours and a watch may be possible. ..Bentley/Goss.. 08/07/2019 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...APX...MQT...GRB...DLH...ARX...MPX... LAT...LON 46339305 46719229 46929072 46709030 46968910 46818756 46688663 46838537 46768487 46438476 46128584 45968666 45488739 45158763 44928819 44818940 44689108 45059209 45179235 45419274 45779325 46339305 Read more

000
ABPZ20 KNHC 071753
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 AM PDT Wed Aug 7 2019

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

A low pressure area is forecast to form a few hundred miles south
of the southern coast of Mexico by the end of the week. Thereafter,
environmental conditions are expected to be somewhat conducive for
development, and a tropical depression could form early next week
while it moves west-northwestward at 10 to 15 mph, within a couple
of hundred miles of the coast of southwestern Mexico.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 5 days...medium...50 percent.

$$
Forecaster Blake

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 PM CDT Wed Aug 07 2019 Valid 081200Z - 091200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MIDWEST INTO PA/NY... ...SUMMARY... Strong to severe thunderstorms capable of isolated large hail and damaging wind gusts will be possible Thursday afternoon and evening from parts of Indiana and Ohio into Pennsylvania and New York. ...Midwest into PA/NY... A northwesterly mid/upper-level jet will overspread much of the Midwest on Thursday as an upper low remains centered over Hudson Bay and Ontario. A shortwave trough embedded within the upper trough is expected to move across the Great Lakes into the Northeast and Quebec through the period. The strongest mid-level height falls/ascent should generally remain north of the international border. But, low-level convergence along a southeastward-moving front should be sufficient to initiate storms through the day across parts of the Midwest into PA/NY. Isolated convection may be ongoing Thursday across the lower Great Lakes along the cold front. Cloud debris from these early morning storms and modest mid-level lapse rates may temper destabilization somewhat ahead of the cold front, especially with northward extent in NY. Even so, strengthening mid-level winds atop a moist low-level airmass and at least modest diurnal heating will contribute to a sufficiently unstable and sheared environment to support organized storms. Relatively greater storm coverage will probably occur from central OH into western/central PA and western NY where low-level convergence along the front is strongest. Multicell clusters will probably be the dominant storm mode with around 25-35 kt of effective bulk shear, but some marginal supercell structures could also occur. Damaging wind gusts appear to be the main threat with these storms as they spread eastward through the afternoon and early evening, with hail being more isolated due to modest mid-level lapse rates. ...Plains into the Lower/Mid MS Valley... Aided by low-level warm air advection, numerous storms will likely be ongoing at the start of the period across parts of KS into western MO. These storms should weaken through the mid morning as a southwesterly low-level jet slowly weakens. Potential redevelopment from eastern OK into parts of the lower/mid MS Valley remains unclear in the wake of the morning convection. Regardless, around 25-30 kt of mid-level west-northwesterly flow should remain across this region, and occasional storm organization could occur Thursday afternoon along/south of a convectively reinforced boundary if sufficient instability develops. Isolated strong/gusty winds would be the main threat across these areas. Additional storms may form from late Thursday afternoon into the evening along the surface boundary across northern OK/southern KS as a southerly low-level jet strengthens. Marginally severe hail may occur with the strongest cores, and occasional strong downdraft winds may also be noted. Farther west, at least a marginal severe threat should develop across parts of the High Plains Thursday afternoon and evening. Weak upslope low-level flow will transport low to mid 50s dewpoints westward along the I-25 corridor, with low to mid 60s further east. Strong heating will result in at least scattered storm development over higher terrain by early afternoon. Mid-level flow will be relatively modest, but effective shear of 30-40 kt and MLCAPE up to 1500 J/kg should support sporadic strong cells capable of both large hail and perhaps locally damaging gusts during the afternoon and early evening. ...MAXIMUM RISK BY HAZARD... Tornado: 2% - Marginal Wind: 15% - Slight Hail: 5% - Marginal ..Gleason.. 08/07/2019 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 PM CDT Wed Aug 07 2019 Valid 081200Z - 091200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MIDWEST INTO PA/NY... ...SUMMARY... Strong to severe thunderstorms capable of isolated large hail and damaging wind gusts will be possible Thursday afternoon and evening from parts of Indiana and Ohio into Pennsylvania and New York. ...Midwest into PA/NY... A northwesterly mid/upper-level jet will overspread much of the Midwest on Thursday as an upper low remains centered over Hudson Bay and Ontario. A shortwave trough embedded within the upper trough is expected to move across the Great Lakes into the Northeast and Quebec through the period. The strongest mid-level height falls/ascent should generally remain north of the international border. But, low-level convergence along a southeastward-moving front should be sufficient to initiate storms through the day across parts of the Midwest into PA/NY. Isolated convection may be ongoing Thursday across the lower Great Lakes along the cold front. Cloud debris from these early morning storms and modest mid-level lapse rates may temper destabilization somewhat ahead of the cold front, especially with northward extent in NY. Even so, strengthening mid-level winds atop a moist low-level airmass and at least modest diurnal heating will contribute to a sufficiently unstable and sheared environment to support organized storms. Relatively greater storm coverage will probably occur from central OH into western/central PA and western NY where low-level convergence along the front is strongest. Multicell clusters will probably be the dominant storm mode with around 25-35 kt of effective bulk shear, but some marginal supercell structures could also occur. Damaging wind gusts appear to be the main threat with these storms as they spread eastward through the afternoon and early evening, with hail being more isolated due to modest mid-level lapse rates. ...Plains into the Lower/Mid MS Valley... Aided by low-level warm air advection, numerous storms will likely be ongoing at the start of the period across parts of KS into western MO. These storms should weaken through the mid morning as a southwesterly low-level jet slowly weakens. Potential redevelopment from eastern OK into parts of the lower/mid MS Valley remains unclear in the wake of the morning convection. Regardless, around 25-30 kt of mid-level west-northwesterly flow should remain across this region, and occasional storm organization could occur Thursday afternoon along/south of a convectively reinforced boundary if sufficient instability develops. Isolated strong/gusty winds would be the main threat across these areas. Additional storms may form from late Thursday afternoon into the evening along the surface boundary across northern OK/southern KS as a southerly low-level jet strengthens. Marginally severe hail may occur with the strongest cores, and occasional strong downdraft winds may also be noted. Farther west, at least a marginal severe threat should develop across parts of the High Plains Thursday afternoon and evening. Weak upslope low-level flow will transport low to mid 50s dewpoints westward along the I-25 corridor, with low to mid 60s further east. Strong heating will result in at least scattered storm development over higher terrain by early afternoon. Mid-level flow will be relatively modest, but effective shear of 30-40 kt and MLCAPE up to 1500 J/kg should support sporadic strong cells capable of both large hail and perhaps locally damaging gusts during the afternoon and early evening. ...MAXIMUM RISK BY HAZARD... Tornado: 2% - Marginal Wind: 15% - Slight Hail: 5% - Marginal ..Gleason.. 08/07/2019 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 PM CDT Wed Aug 07 2019 Valid 081200Z - 091200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MIDWEST INTO PA/NY... ...SUMMARY... Strong to severe thunderstorms capable of isolated large hail and damaging wind gusts will be possible Thursday afternoon and evening from parts of Indiana and Ohio into Pennsylvania and New York. ...Midwest into PA/NY... A northwesterly mid/upper-level jet will overspread much of the Midwest on Thursday as an upper low remains centered over Hudson Bay and Ontario. A shortwave trough embedded within the upper trough is expected to move across the Great Lakes into the Northeast and Quebec through the period. The strongest mid-level height falls/ascent should generally remain north of the international border. But, low-level convergence along a southeastward-moving front should be sufficient to initiate storms through the day across parts of the Midwest into PA/NY. Isolated convection may be ongoing Thursday across the lower Great Lakes along the cold front. Cloud debris from these early morning storms and modest mid-level lapse rates may temper destabilization somewhat ahead of the cold front, especially with northward extent in NY. Even so, strengthening mid-level winds atop a moist low-level airmass and at least modest diurnal heating will contribute to a sufficiently unstable and sheared environment to support organized storms. Relatively greater storm coverage will probably occur from central OH into western/central PA and western NY where low-level convergence along the front is strongest. Multicell clusters will probably be the dominant storm mode with around 25-35 kt of effective bulk shear, but some marginal supercell structures could also occur. Damaging wind gusts appear to be the main threat with these storms as they spread eastward through the afternoon and early evening, with hail being more isolated due to modest mid-level lapse rates. ...Plains into the Lower/Mid MS Valley... Aided by low-level warm air advection, numerous storms will likely be ongoing at the start of the period across parts of KS into western MO. These storms should weaken through the mid morning as a southwesterly low-level jet slowly weakens. Potential redevelopment from eastern OK into parts of the lower/mid MS Valley remains unclear in the wake of the morning convection. Regardless, around 25-30 kt of mid-level west-northwesterly flow should remain across this region, and occasional storm organization could occur Thursday afternoon along/south of a convectively reinforced boundary if sufficient instability develops. Isolated strong/gusty winds would be the main threat across these areas. Additional storms may form from late Thursday afternoon into the evening along the surface boundary across northern OK/southern KS as a southerly low-level jet strengthens. Marginally severe hail may occur with the strongest cores, and occasional strong downdraft winds may also be noted. Farther west, at least a marginal severe threat should develop across parts of the High Plains Thursday afternoon and evening. Weak upslope low-level flow will transport low to mid 50s dewpoints westward along the I-25 corridor, with low to mid 60s further east. Strong heating will result in at least scattered storm development over higher terrain by early afternoon. Mid-level flow will be relatively modest, but effective shear of 30-40 kt and MLCAPE up to 1500 J/kg should support sporadic strong cells capable of both large hail and perhaps locally damaging gusts during the afternoon and early evening. ...MAXIMUM RISK BY HAZARD... Tornado: 2% - Marginal Wind: 15% - Slight Hail: 5% - Marginal ..Gleason.. 08/07/2019 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 PM CDT Wed Aug 07 2019 Valid 081200Z - 091200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MIDWEST INTO PA/NY... ...SUMMARY... Strong to severe thunderstorms capable of isolated large hail and damaging wind gusts will be possible Thursday afternoon and evening from parts of Indiana and Ohio into Pennsylvania and New York. ...Midwest into PA/NY... A northwesterly mid/upper-level jet will overspread much of the Midwest on Thursday as an upper low remains centered over Hudson Bay and Ontario. A shortwave trough embedded within the upper trough is expected to move across the Great Lakes into the Northeast and Quebec through the period. The strongest mid-level height falls/ascent should generally remain north of the international border. But, low-level convergence along a southeastward-moving front should be sufficient to initiate storms through the day across parts of the Midwest into PA/NY. Isolated convection may be ongoing Thursday across the lower Great Lakes along the cold front. Cloud debris from these early morning storms and modest mid-level lapse rates may temper destabilization somewhat ahead of the cold front, especially with northward extent in NY. Even so, strengthening mid-level winds atop a moist low-level airmass and at least modest diurnal heating will contribute to a sufficiently unstable and sheared environment to support organized storms. Relatively greater storm coverage will probably occur from central OH into western/central PA and western NY where low-level convergence along the front is strongest. Multicell clusters will probably be the dominant storm mode with around 25-35 kt of effective bulk shear, but some marginal supercell structures could also occur. Damaging wind gusts appear to be the main threat with these storms as they spread eastward through the afternoon and early evening, with hail being more isolated due to modest mid-level lapse rates. ...Plains into the Lower/Mid MS Valley... Aided by low-level warm air advection, numerous storms will likely be ongoing at the start of the period across parts of KS into western MO. These storms should weaken through the mid morning as a southwesterly low-level jet slowly weakens. Potential redevelopment from eastern OK into parts of the lower/mid MS Valley remains unclear in the wake of the morning convection. Regardless, around 25-30 kt of mid-level west-northwesterly flow should remain across this region, and occasional storm organization could occur Thursday afternoon along/south of a convectively reinforced boundary if sufficient instability develops. Isolated strong/gusty winds would be the main threat across these areas. Additional storms may form from late Thursday afternoon into the evening along the surface boundary across northern OK/southern KS as a southerly low-level jet strengthens. Marginally severe hail may occur with the strongest cores, and occasional strong downdraft winds may also be noted. Farther west, at least a marginal severe threat should develop across parts of the High Plains Thursday afternoon and evening. Weak upslope low-level flow will transport low to mid 50s dewpoints westward along the I-25 corridor, with low to mid 60s further east. Strong heating will result in at least scattered storm development over higher terrain by early afternoon. Mid-level flow will be relatively modest, but effective shear of 30-40 kt and MLCAPE up to 1500 J/kg should support sporadic strong cells capable of both large hail and perhaps locally damaging gusts during the afternoon and early evening. ...MAXIMUM RISK BY HAZARD... Tornado: 2% - Marginal Wind: 15% - Slight Hail: 5% - Marginal ..Gleason.. 08/07/2019 Read more

MD 1665 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR FAR EASTERN NEW YORK...VERMONT...AND NEW HAMPSHIRE
Mesoscale Discussion 1665 NWS Storm Prediction Center Norman OK 1226 PM CDT Wed Aug 07 2019 Areas affected...Far eastern New York...Vermont...and New Hampshire Concerning...Severe potential...Watch possible Valid 071726Z - 071900Z Probability of Watch Issuance...40 percent SUMMARY...Strong to occasionally severe storms are expected this afternoon and evening. Damaging winds will be the primary threat. DISCUSSION...Morning cloud cover has slowed heating across eastern New York, Vermont, and New Hampshire so far today. However, cloud cover is becoming less numerous and thus surface heating has increased across the area in the last 1 to 2 hours. Visible satellite is starting to show surface based cumulus development suggesting that instability is increasing. Currently MLCAPE is around 1000 J/kg across this region, but additional surface heating/moistening will increase instability to 1500 to 2000 J/kg by later this afternoon. As instability increases, expect storm coverage to increase through the afternoon. Weak mid-level lapse rates (5.5-6 C/km), and effective shear around 25 knots will limit the overall severe weather threat, but given the instability and storm coverage expected, a few severe storms are possible. A watch may be needed if storms are more intense/organized than expected, but current thinking is that a watch will not be needed across this region. ..Bentley/Goss.. 08/07/2019 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...GYX...BOX...BTV...ALY...BGM...BUF... LAT...LON 45197391 44897557 43977551 43187541 42887364 42707220 42707110 43667111 44857092 45497106 45197391 Read more

No watches are valid as of Wed Aug 7 17:04:01 UTC 2019.

MD 1664 CONCERNING SEVERE POTENTIAL...WATCH LIKELY FOR THE MID-ATLANTIC INTO PORTIONS OF THE NORTHEAST
Mesoscale Discussion 1664 NWS Storm Prediction Center Norman OK 1202 PM CDT Wed Aug 07 2019 Areas affected...The mid-Atlantic into portions of the Northeast Concerning...Severe potential...Watch likely Valid 071702Z - 071830Z Probability of Watch Issuance...95 percent SUMMARY...Strong to severe storms are expected this afternoon and evening with a threat for large hail and damaging winds. A watch is likely. DISCUSSION...Numerous storms have started to develop from the Mid-Atlantic into portions of the Northeast in an environment with temperatures in the 80s and dewpoints from the upper 60s to mid 70s. Effective shear around 30 knots will support multicell clusters and lines capable of both large hail and damaging winds. Mid-level lapse rates around 6.5 to 7 C/km will support a greater threat for large hail in this region than farther south across Virginia and North Carolina. The greatest threat for both large hail and damaging winds will be from central Maryland northeast into far southeast New York where storm coverage, instability, and shear will be maximized ahead of an MCV currently out of far eastern West Virginia. A watch will be issued soon. ..Bentley/Goss.. 08/07/2019 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...GYX...BOX...OKX...ALY...PHI...BGM...AKQ...CTP... LWX... LAT...LON 41417612 42407495 42957379 43037164 42517087 42137012 41576996 41237099 41047222 40627298 39907399 39077453 38127498 37867533 37747602 37837684 37977744 38457775 38987784 39847771 41077665 41417612 Read more