Tropical Storm Ivo Forecast Discussion Number 2

5 years 11 months ago
Issued at 300 PM MDT Wed Aug 21 2019 000 WTPZ45 KNHC 212034 TCDEP5 Tropical Storm Ivo Discussion Number 2 NWS National Hurricane Center Miami FL EP102014 300 PM MDT Wed Aug 21 2019 Over the past several hours the cyclone has exhibited an ongoing increase in organization, with a curved band wrapping around the low level center apparent in both satellite imagery and microwave data. The initial intensity has been increased to 40 kt and this is a blend of the subjective Dvorak intensity estimates from TAFB and SAB. Ivo's initial motion is 285/17 kt. A mid-level ridge to the north of the cyclone will continue to steer it to the west-northwest through much of tonight. By Thursday, a weakness is expected to develop to the northwest of the cyclone which will result in a turn to the northwest with a decrease in forward speed. The cyclone is then forecast to continue to move northwest through the remainder of the forecast period. Ivo will be over warm SSTs near 30C and in a moist environment for the next 48 hours, which should favor intensification. And, although the SHIPS guidance suggests 15 kt of northeasterly shear may be affecting the cyclone, the satellite appearance does not suggest that this shear is having much of impact at this time. Based on the favorable environment, steady strengthening is forecast, and Ivo is expected to become a hurricane by Friday. By 72 hours, the cyclone will begin to move over much cooler waters and into a stable air mass while undergoing increasing southwesterly shear. This should cause the cyclone to weaken and it is expected to become a convection-free post-tropical cyclone by day 5. The official forecast has been increased slightly from the previous one and is close to the corrected consensus HCCA. FORECAST POSITIONS AND MAX WINDS INIT 21/2100Z 15.8N 109.5W 40 KT 45 MPH 12H 22/0600Z 16.4N 111.6W 50 KT 60 MPH 24H 22/1800Z 17.2N 113.8W 60 KT 70 MPH 36H 23/0600Z 18.2N 115.3W 70 KT 80 MPH 48H 23/1800Z 19.5N 116.4W 70 KT 80 MPH 72H 24/1800Z 22.5N 117.9W 55 KT 65 MPH 96H 25/1800Z 25.8N 119.9W 40 KT 45 MPH 120H 26/1800Z 28.8N 121.9W 30 KT 35 MPH...POST-TROPICAL $$ Forecaster Latto/Pasch
NHC Webmaster

Tropical Storm Ivo Wind Speed Probabilities Number 2

5 years 11 months ago
Issued at 2100 UTC WED AUG 21 2019 000 FOPZ15 KNHC 212034 PWSEP5 TROPICAL STORM IVO WIND SPEED PROBABILITIES NUMBER 2 NWS NATIONAL HURRICANE CENTER MIAMI FL EP102019 2100 UTC WED AUG 21 2019 AT 2100Z THE CENTER OF TROPICAL STORM IVO WAS LOCATED NEAR LATITUDE 15.8 NORTH...LONGITUDE 109.5 WEST WITH MAXIMUM SUSTAINED WINDS NEAR 40 KTS...45 MPH...75 KM/H. Z INDICATES COORDINATED UNIVERSAL TIME (GREENWICH) PACIFIC DAYLIGHT TIME (PDT)...SUBTRACT 7 HOURS FROM Z TIME HAWAIIAN STANDARD TIME (HST)...SUBTRACT 10 HOURS FROM Z TIME WIND SPEED PROBABILITY TABLE FOR SPECIFIC LOCATIONS CHANCES OF SUSTAINED (1-MINUTE AVERAGE) WIND SPEEDS OF AT LEAST ...34 KT (39 MPH... 63 KM/H)... ...50 KT (58 MPH... 93 KM/H)... ...64 KT (74 MPH...119 KM/H)... FOR LOCATIONS AND TIME PERIODS DURING THE NEXT 5 DAYS PROBABILITIES FOR LOCATIONS ARE GIVEN AS OP(CP) WHERE OP IS THE PROBABILITY OF THE EVENT BEGINNING DURING AN INDIVIDUAL TIME PERIOD (ONSET PROBABILITY) (CP) IS THE PROBABILITY OF THE EVENT OCCURRING BETWEEN 18Z WED AND THE FORECAST HOUR (CUMULATIVE PROBABILITY) PROBABILITIES ARE GIVEN IN PERCENT X INDICATES PROBABILITIES LESS THAN 1 PERCENT PROBABILITIES FOR 34 KT AND 50 KT ARE SHOWN AT A GIVEN LOCATION WHEN THE 5-DAY CUMULATIVE PROBABILITY IS AT LEAST 3 PERCENT. PROBABILITIES FOR 34...50...64 KT SHOWN WHEN THE 5-DAY 64-KT CUMULATIVE PROBABILITY IS AT LEAST 1 PERCENT. - - - - WIND SPEED PROBABILITIES FOR SELECTED LOCATIONS - - - - FROM FROM FROM FROM FROM FROM FROM TIME 18Z WED 06Z THU 18Z THU 06Z FRI 18Z FRI 18Z SAT 18Z SUN PERIODS TO TO TO TO TO TO TO 06Z THU 18Z THU 06Z FRI 18Z FRI 18Z SAT 18Z SUN 18Z MON FORECAST HOUR (12) (24) (36) (48) (72) (96) (120) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - LOCATION KT IS GUADALUPE 34 X X( X) X( X) X( X) X( X) 4( 4) 3( 7) ISLA SOCORRO 34 X 2( 2) 2( 4) 2( 6) X( 6) X( 6) X( 6) ISLA CLARION 34 X 18(18) 61(79) 5(84) X(84) X(84) X(84) ISLA CLARION 50 X 2( 2) 42(44) 4(48) 1(49) X(49) X(49) ISLA CLARION 64 X X( X) 19(19) 4(23) X(23) X(23) X(23) 15N 115W 34 X 2( 2) 3( 5) 2( 7) 1( 8) X( 8) X( 8) 20N 115W 34 X 2( 2) 23(25) 27(52) 4(56) X(56) X(56) 20N 115W 50 X X( X) 3( 3) 13(16) 2(18) X(18) X(18) 20N 115W 64 X X( X) 1( 1) 4( 5) 1( 6) X( 6) X( 6) 25N 115W 34 X X( X) X( X) 1( 1) 5( 6) 3( 9) X( 9) 20N 120W 34 X X( X) 2( 2) 3( 5) 14(19) 1(20) X(20) 20N 120W 50 X X( X) X( X) X( X) 3( 3) X( 3) X( 3) 25N 120W 34 X X( X) X( X) X( X) 7( 7) 25(32) 3(35) 25N 120W 50 X X( X) X( X) X( X) 1( 1) 7( 8) X( 8) 25N 120W 64 X X( X) X( X) X( X) X( X) 2( 2) X( 2) 30N 120W 34 X X( X) X( X) X( X) X( X) 2( 2) 4( 6) 30N 125W 34 X X( X) X( X) X( X) X( X) 1( 1) 2( 3) $$ FORECASTER LATTO/PASCH
NHC Webmaster

Tropical Storm Ivo Forecast Advisory Number 2

5 years 11 months ago
Issued at 2100 UTC WED AUG 21 2019 000 WTPZ25 KNHC 212034 TCMEP5 TROPICAL STORM IVO FORECAST/ADVISORY NUMBER 2 NWS NATIONAL HURRICANE CENTER MIAMI FL EP102019 2100 UTC WED AUG 21 2019 THERE ARE NO COASTAL WATCHES OR WARNINGS IN EFFECT. TROPICAL STORM CENTER LOCATED NEAR 15.8N 109.5W AT 21/2100Z POSITION ACCURATE WITHIN 40 NM PRESENT MOVEMENT TOWARD THE WEST-NORTHWEST OR 285 DEGREES AT 17 KT ESTIMATED MINIMUM CENTRAL PRESSURE 1004 MB MAX SUSTAINED WINDS 40 KT WITH GUSTS TO 50 KT. 34 KT....... 30NE 0SE 0SW 30NW. WINDS AND SEAS VARY GREATLY IN EACH QUADRANT. RADII IN NAUTICAL MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT. REPEAT...CENTER LOCATED NEAR 15.8N 109.5W AT 21/2100Z AT 21/1800Z CENTER WAS LOCATED NEAR 15.6N 108.8W FORECAST VALID 22/0600Z 16.4N 111.6W MAX WIND 50 KT...GUSTS 60 KT. 50 KT... 20NE 0SE 0SW 0NW. 34 KT... 40NE 0SE 0SW 40NW. FORECAST VALID 22/1800Z 17.2N 113.8W MAX WIND 60 KT...GUSTS 75 KT. 50 KT... 30NE 0SE 0SW 0NW. 34 KT... 60NE 60SE 60SW 50NW. FORECAST VALID 23/0600Z 18.2N 115.3W MAX WIND 70 KT...GUSTS 85 KT. 64 KT... 15NE 0SE 0SW 0NW. 50 KT... 30NE 20SE 0SW 0NW. 34 KT... 70NE 80SE 80SW 50NW. FORECAST VALID 23/1800Z 19.5N 116.4W MAX WIND 70 KT...GUSTS 85 KT. 64 KT... 15NE 0SE 0SW 0NW. 50 KT... 30NE 20SE 0SW 0NW. 34 KT... 80NE 80SE 80SW 50NW. FORECAST VALID 24/1800Z 22.5N 117.9W MAX WIND 55 KT...GUSTS 65 KT. 50 KT... 20NE 20SE 0SW 0NW. 34 KT... 70NE 70SE 50SW 40NW. EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 100 NM ON DAY 4 AND 150 NM ON DAY 5...AND FOR INTENSITY NEAR 15 KT EACH DAY OUTLOOK VALID 25/1800Z 25.8N 119.9W MAX WIND 40 KT...GUSTS 50 KT. OUTLOOK VALID 26/1800Z 28.8N 121.9W...POST-TROPICAL MAX WIND 30 KT...GUSTS 40 KT. REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 15.8N 109.5W NEXT ADVISORY AT 22/0300Z $$ FORECASTER LATTO/PASCH
NHC Webmaster

Tropical Storm Ivo Public Advisory Number 2

5 years 11 months ago
Issued at 300 PM MDT Wed Aug 21 2019 000 WTPZ35 KNHC 212034 TCPEP5 BULLETIN Tropical Storm Ivo Advisory Number 2 NWS National Hurricane Center Miami FL EP102014 300 PM MDT Wed Aug 21 2019 ...DEPRESSION BECOMES TROPICAL STORM IVO... ...EXPECTED TO INTENSIFY INTO A HURRICANE BY FRIDAY... SUMMARY OF 300 PM MDT...2100 UTC...INFORMATION ---------------------------------------------- LOCATION...15.8N 109.5W ABOUT 490 MI...790 KM S OF THE SOUTHERN TIP OF BAJA CALIFORNIA MAXIMUM SUSTAINED WINDS...45 MPH...75 KM/H PRESENT MOVEMENT...WNW OR 285 DEGREES AT 20 MPH...31 KM/H MINIMUM CENTRAL PRESSURE...1004 MB...29.65 INCHES WATCHES AND WARNINGS -------------------- There are no coastal watches or warnings in effect. DISCUSSION AND OUTLOOK ---------------------- At 300 PM MDT (2100 UTC), the center of Tropical Storm Ivo was located near latitude 15.8 North, longitude 109.5 West. Ivo is moving toward the west-northwest near 20 mph (31 km/h). A decrease in forward speed and a turn to the northwest is expected by Thursday, with a northwestward motion continuing through Friday. Maximum sustained winds are near 45 mph (75 km/h) with higher gusts. Steady strengthening is expected and Ivo is forecast to become a hurricane by Friday. Tropical-storm-force winds extend outward up to 35 miles (55 km) from the center. The estimated minimum central pressure is 1004 mb (29.65 inches). HAZARDS AFFECTING LAND ---------------------- None NEXT ADVISORY ------------- Next complete advisory at 900 PM MDT. $$ Forecaster Latto/Pasch
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SPC Severe Thunderstorm Watch 610 Status Reports

5 years 11 months ago
WW 0610 Status Updates
STATUS REPORT ON WW 610 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..KERR..08/21/19 ATTN...WFO...LWX...PHI...CTP... STATUS REPORT FOR WS 610 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS DEC001-003-005-212140- DE . DELAWARE COUNTIES INCLUDED ARE KENT NEW CASTLE SUSSEX DCC001-212140- DC . DISTRICT OF COLUMBIA COUNTIES INCLUDED ARE DISTRICT OF COLUMBIA MDC003-005-009-011-013-015-017-021-025-027-029-031-033-035-041- 510-212140- MD . MARYLAND COUNTIES INCLUDED ARE ANNE ARUNDEL BALTIMORE CALVERT CAROLINE CARROLL CECIL CHARLES FREDERICK HARFORD HOWARD KENT MONTGOMERY Read more

SPC Severe Thunderstorm Watch 609 Status Reports

5 years 11 months ago
WW 0609 Status Updates
140- STATUS REPORT ON WW 609 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..KERR..08/21/19 ATTN...WFO...OKX...BOX...ALY...GYX... STATUS REPORT FOR WS 609 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS CTC001-003-005-007-009-011-013-015-212140- CT . CONNECTICUT COUNTIES INCLUDED ARE FAIRFIELD HARTFORD LITCHFIELD MIDDLESEX NEW HAVEN NEW LONDON TOLLAND WINDHAM MEC031-212140- ME . MAINE COUNTIES INCLUDED ARE YORK MAC001-003-005-007-009-011-013-015-017-019-021-023-025-027- 212140- MA . MASSACHUSETTS COUNTIES INCLUDED ARE BARNSTABLE BERKSHIRE BRISTOL Read more

SPC Aug 21, 2019 2000 UTC Day 1 Convective Outlook

5 years 11 months ago
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0257 PM CDT Wed Aug 21 2019 Valid 212000Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHEAST AND MID ATLANTIC REGION...AS WELL AS OVER PARTS OF THE COLORADO FRONT RANGE... ...SUMMARY... Severe thunderstorms will continue this afternoon and evening across parts of the Northeast/Mid-Atlantic States, while a few severe storms will be possible across the central high Plains. ...Discussion... The overall outlook remains on track, with respect to prior forecast reasoning. The main changes in this update will be to extend the eastern U.S. SLGT risk a bit farther south across parts of the mid Atlantic region, while removing northern portions of the risk in parts of New England, and to include a small SLGT risk over the Colorado Front Range. In the East, clouds remain dense, and the airmass stable, over northern portions of Vermont and New Hampshire, with the primary severe risk likely to remain south of these areas. Meanwhile, with recently issued WW #610 extending southward to the Chesapeake Bay region, SLGT risk is correspondingly being expanded slightly southward. In Colorado, shear remains modest -- particularly with southward extent. However, with moderate destabilization occurring, and thus risk for locally intense cells within a narrow corridor, potential for hail/wind with a few of the strongest storms warrants upgrade to a small SLGT risk in this area. Otherwise, no major changes to the outlook are required at this time. ..Goss.. 08/21/2019 .PREV DISCUSSION... /ISSUED 1132 AM CDT Wed Aug 21 2019/ ...Northeast/Mid-Atlantic States... A shortwave trough will continue to progress east-northeastward from eastern New York toward northern New England, while a warm front slowly spreads northward across southern New England. With broken cloud cover lingering in most areas, modest overall destabilization is expected along/south of the warm front where low-level/deep-layer shear will be maximized. The environment will support the possibility of supercells/bowing segments particularly across southeast New York and southern New England, with severe hail/wind possible along with some tornado risk. Multicells with damaging winds are possible farther south within the warm sector. For additional short-term details, see Mesoscale Discussion 1825. ...Kansas/Missouri/far southeast Nebraska to Missouri/Illinois... The remnants of overnight convection continue to decay across the region with cloud cover/outflow influencing an effective boundary across southern portions of Kansas/Missouri. Surface-based thunderstorms should develop/intensify later this afternoon particularly across southern/eastern Kansas into western Missouri within a moist/unstable environment. Relatively weak tropospheric winds may limit overall storm organization, but the strongest storms will pose a damaging wind/severe hail risk. ...Wyoming/Colorado Front Range to central High Plains... Isolated to widely scattered thunderstorms should develop this afternoon over the eastern mountains and foothills from northern Wyoming across central/southern Colorado, offering the potential for isolated severe hail and gusts. Activity is expected predominantly in the post-frontal/upslope region where lift is maximized by a combination of upslope flow and diabatic surface heating of the higher terrain (minimizing MLCINH). Mid-level flow is forecast to be modest; however, vertical shear will be stronger than over lower elevations ahead of the front because of the backed boundary-layer winds and relatively extended low-level hodographs. As such, a mixture of supercellular and multicellular structures are possible. Read more

SPC Aug 21, 2019 2000 UTC Day 1 Convective Outlook

5 years 11 months ago
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0257 PM CDT Wed Aug 21 2019 Valid 212000Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHEAST AND MID ATLANTIC REGION...AS WELL AS OVER PARTS OF THE COLORADO FRONT RANGE... ...SUMMARY... Severe thunderstorms will continue this afternoon and evening across parts of the Northeast/Mid-Atlantic States, while a few severe storms will be possible across the central high Plains. ...Discussion... The overall outlook remains on track, with respect to prior forecast reasoning. The main changes in this update will be to extend the eastern U.S. SLGT risk a bit farther south across parts of the mid Atlantic region, while removing northern portions of the risk in parts of New England, and to include a small SLGT risk over the Colorado Front Range. In the East, clouds remain dense, and the airmass stable, over northern portions of Vermont and New Hampshire, with the primary severe risk likely to remain south of these areas. Meanwhile, with recently issued WW #610 extending southward to the Chesapeake Bay region, SLGT risk is correspondingly being expanded slightly southward. In Colorado, shear remains modest -- particularly with southward extent. However, with moderate destabilization occurring, and thus risk for locally intense cells within a narrow corridor, potential for hail/wind with a few of the strongest storms warrants upgrade to a small SLGT risk in this area. Otherwise, no major changes to the outlook are required at this time. ..Goss.. 08/21/2019 .PREV DISCUSSION... /ISSUED 1132 AM CDT Wed Aug 21 2019/ ...Northeast/Mid-Atlantic States... A shortwave trough will continue to progress east-northeastward from eastern New York toward northern New England, while a warm front slowly spreads northward across southern New England. With broken cloud cover lingering in most areas, modest overall destabilization is expected along/south of the warm front where low-level/deep-layer shear will be maximized. The environment will support the possibility of supercells/bowing segments particularly across southeast New York and southern New England, with severe hail/wind possible along with some tornado risk. Multicells with damaging winds are possible farther south within the warm sector. For additional short-term details, see Mesoscale Discussion 1825. ...Kansas/Missouri/far southeast Nebraska to Missouri/Illinois... The remnants of overnight convection continue to decay across the region with cloud cover/outflow influencing an effective boundary across southern portions of Kansas/Missouri. Surface-based thunderstorms should develop/intensify later this afternoon particularly across southern/eastern Kansas into western Missouri within a moist/unstable environment. Relatively weak tropospheric winds may limit overall storm organization, but the strongest storms will pose a damaging wind/severe hail risk. ...Wyoming/Colorado Front Range to central High Plains... Isolated to widely scattered thunderstorms should develop this afternoon over the eastern mountains and foothills from northern Wyoming across central/southern Colorado, offering the potential for isolated severe hail and gusts. Activity is expected predominantly in the post-frontal/upslope region where lift is maximized by a combination of upslope flow and diabatic surface heating of the higher terrain (minimizing MLCINH). Mid-level flow is forecast to be modest; however, vertical shear will be stronger than over lower elevations ahead of the front because of the backed boundary-layer winds and relatively extended low-level hodographs. As such, a mixture of supercellular and multicellular structures are possible. Read more

SPC Aug 21, 2019 2000 UTC Day 1 Convective Outlook

5 years 11 months ago
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0257 PM CDT Wed Aug 21 2019 Valid 212000Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHEAST AND MID ATLANTIC REGION...AS WELL AS OVER PARTS OF THE COLORADO FRONT RANGE... ...SUMMARY... Severe thunderstorms will continue this afternoon and evening across parts of the Northeast/Mid-Atlantic States, while a few severe storms will be possible across the central high Plains. ...Discussion... The overall outlook remains on track, with respect to prior forecast reasoning. The main changes in this update will be to extend the eastern U.S. SLGT risk a bit farther south across parts of the mid Atlantic region, while removing northern portions of the risk in parts of New England, and to include a small SLGT risk over the Colorado Front Range. In the East, clouds remain dense, and the airmass stable, over northern portions of Vermont and New Hampshire, with the primary severe risk likely to remain south of these areas. Meanwhile, with recently issued WW #610 extending southward to the Chesapeake Bay region, SLGT risk is correspondingly being expanded slightly southward. In Colorado, shear remains modest -- particularly with southward extent. However, with moderate destabilization occurring, and thus risk for locally intense cells within a narrow corridor, potential for hail/wind with a few of the strongest storms warrants upgrade to a small SLGT risk in this area. Otherwise, no major changes to the outlook are required at this time. ..Goss.. 08/21/2019 .PREV DISCUSSION... /ISSUED 1132 AM CDT Wed Aug 21 2019/ ...Northeast/Mid-Atlantic States... A shortwave trough will continue to progress east-northeastward from eastern New York toward northern New England, while a warm front slowly spreads northward across southern New England. With broken cloud cover lingering in most areas, modest overall destabilization is expected along/south of the warm front where low-level/deep-layer shear will be maximized. The environment will support the possibility of supercells/bowing segments particularly across southeast New York and southern New England, with severe hail/wind possible along with some tornado risk. Multicells with damaging winds are possible farther south within the warm sector. For additional short-term details, see Mesoscale Discussion 1825. ...Kansas/Missouri/far southeast Nebraska to Missouri/Illinois... The remnants of overnight convection continue to decay across the region with cloud cover/outflow influencing an effective boundary across southern portions of Kansas/Missouri. Surface-based thunderstorms should develop/intensify later this afternoon particularly across southern/eastern Kansas into western Missouri within a moist/unstable environment. Relatively weak tropospheric winds may limit overall storm organization, but the strongest storms will pose a damaging wind/severe hail risk. ...Wyoming/Colorado Front Range to central High Plains... Isolated to widely scattered thunderstorms should develop this afternoon over the eastern mountains and foothills from northern Wyoming across central/southern Colorado, offering the potential for isolated severe hail and gusts. Activity is expected predominantly in the post-frontal/upslope region where lift is maximized by a combination of upslope flow and diabatic surface heating of the higher terrain (minimizing MLCINH). Mid-level flow is forecast to be modest; however, vertical shear will be stronger than over lower elevations ahead of the front because of the backed boundary-layer winds and relatively extended low-level hodographs. As such, a mixture of supercellular and multicellular structures are possible. Read more

SPC Aug 21, 2019 2000 UTC Day 1 Convective Outlook

5 years 11 months ago
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0257 PM CDT Wed Aug 21 2019 Valid 212000Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHEAST AND MID ATLANTIC REGION...AS WELL AS OVER PARTS OF THE COLORADO FRONT RANGE... ...SUMMARY... Severe thunderstorms will continue this afternoon and evening across parts of the Northeast/Mid-Atlantic States, while a few severe storms will be possible across the central high Plains. ...Discussion... The overall outlook remains on track, with respect to prior forecast reasoning. The main changes in this update will be to extend the eastern U.S. SLGT risk a bit farther south across parts of the mid Atlantic region, while removing northern portions of the risk in parts of New England, and to include a small SLGT risk over the Colorado Front Range. In the East, clouds remain dense, and the airmass stable, over northern portions of Vermont and New Hampshire, with the primary severe risk likely to remain south of these areas. Meanwhile, with recently issued WW #610 extending southward to the Chesapeake Bay region, SLGT risk is correspondingly being expanded slightly southward. In Colorado, shear remains modest -- particularly with southward extent. However, with moderate destabilization occurring, and thus risk for locally intense cells within a narrow corridor, potential for hail/wind with a few of the strongest storms warrants upgrade to a small SLGT risk in this area. Otherwise, no major changes to the outlook are required at this time. ..Goss.. 08/21/2019 .PREV DISCUSSION... /ISSUED 1132 AM CDT Wed Aug 21 2019/ ...Northeast/Mid-Atlantic States... A shortwave trough will continue to progress east-northeastward from eastern New York toward northern New England, while a warm front slowly spreads northward across southern New England. With broken cloud cover lingering in most areas, modest overall destabilization is expected along/south of the warm front where low-level/deep-layer shear will be maximized. The environment will support the possibility of supercells/bowing segments particularly across southeast New York and southern New England, with severe hail/wind possible along with some tornado risk. Multicells with damaging winds are possible farther south within the warm sector. For additional short-term details, see Mesoscale Discussion 1825. ...Kansas/Missouri/far southeast Nebraska to Missouri/Illinois... The remnants of overnight convection continue to decay across the region with cloud cover/outflow influencing an effective boundary across southern portions of Kansas/Missouri. Surface-based thunderstorms should develop/intensify later this afternoon particularly across southern/eastern Kansas into western Missouri within a moist/unstable environment. Relatively weak tropospheric winds may limit overall storm organization, but the strongest storms will pose a damaging wind/severe hail risk. ...Wyoming/Colorado Front Range to central High Plains... Isolated to widely scattered thunderstorms should develop this afternoon over the eastern mountains and foothills from northern Wyoming across central/southern Colorado, offering the potential for isolated severe hail and gusts. Activity is expected predominantly in the post-frontal/upslope region where lift is maximized by a combination of upslope flow and diabatic surface heating of the higher terrain (minimizing MLCINH). Mid-level flow is forecast to be modest; however, vertical shear will be stronger than over lower elevations ahead of the front because of the backed boundary-layer winds and relatively extended low-level hodographs. As such, a mixture of supercellular and multicellular structures are possible. Read more

SPC MD 1827

5 years 11 months ago
MD 1827 CONCERNING SEVERE THUNDERSTORM WATCH 609... FOR HUDSON VALLEY INTO SOUTHERN NEW ENGLAND
Mesoscale Discussion 1827 NWS Storm Prediction Center Norman OK 0255 PM CDT Wed Aug 21 2019 Areas affected...Hudson Valley into southern New England Concerning...Severe Thunderstorm Watch 609... Valid 211955Z - 212130Z The severe weather threat for Severe Thunderstorm Watch 609 continues. SUMMARY...Thunderstorm activity will continue to develop and intensify across the region through 5-7 PM EDT, posing a risk for damaging wind gusts, and perhaps at least some continuing risk for a tornado or two. DISCUSSION...The initial convective band has largely dissipated, but widely scattered, generally discrete vigorous thunderstorms have developed and persisted. This includes one storm which still could take on an increasing supercell structure as it tracks near/northwest of Providence RI during the next hour or so. Convection north of Albany appears to be gradually growing upscale, with potential to produce a swath of damaging winds becoming more apparent. Further intensification and organization appears possible, as it tracks eastward along an effective warm frontal zone near/north of the Massachusetts/Vermont and New Hampshire border area through 21-23Z. Additional new thunderstorm development is ongoing within surface troughing, near/east of the Catskills and Poconos. In the presence of moderate instability and shear, this activity is expected to intensify further and gradually pose increasing potential for strong surface gusts across the lower Hudson Valley into southern New England and Long Island. ..Kerr.. 08/21/2019 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...GYX...BOX...BTV...OKX...ALY...PHI...BGM... LAT...LON 43587342 43537203 42807084 41917075 41387192 41027248 40657350 40457445 40657537 41757469 43587342 Read more

Hay feeding increased in central Texas

5 years 11 months ago
Rangelands and pastures in central Texas received some rain, but still needed more, and hay feeding increased. Livestock conditions were deteriorating, due to drought and heat. Producers needed rain to plow small grain seedbeds to prepare for planting. Soil moisture levels were short in nearly all counties in the district. Bryan-College Station Eagle (Texas), Aug. 20, 2019

SPC Severe Thunderstorm Watch 609 Status Reports

5 years 11 months ago
WW 0609 Status Updates
040- STATUS REPORT ON WW 609 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..KERR..08/21/19 ATTN...WFO...OKX...BOX...ALY...GYX... STATUS REPORT FOR WS 609 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS CTC001-003-005-007-009-011-013-015-212040- CT . CONNECTICUT COUNTIES INCLUDED ARE FAIRFIELD HARTFORD LITCHFIELD MIDDLESEX NEW HAVEN NEW LONDON TOLLAND WINDHAM MEC031-212040- ME . MAINE COUNTIES INCLUDED ARE YORK MAC001-003-005-007-009-011-013-015-017-019-021-023-025-027- 212040- MA . MASSACHUSETTS COUNTIES INCLUDED ARE BARNSTABLE BERKSHIRE BRISTOL Read more

SPC MD 1826

5 years 11 months ago
MD 1826 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR THE COLORADO FRONT RANGE TO PORTIONS OF SOUTHEAST WYOMING
Mesoscale Discussion 1826 NWS Storm Prediction Center Norman OK 0151 PM CDT Wed Aug 21 2019 Areas affected...The Colorado front range to portions of southeast Wyoming Concerning...Severe potential...Watch possible Valid 211851Z - 212045Z Probability of Watch Issuance...40 percent SUMMARY...Thunderstorms will develop/intensify through early afternoon and pose a threat for severe hail and brief severe wind gusts. The potential coverage of the threat, and hence the need for a Severe Thunderstorm Watch, is uncertain. DISCUSSION...Strong heating and an approaching weak mid-upper-level low are contributing to deepening cumulus and initial thunderstorm development over the Colorado and Wyoming high terrain. A moist and modifying continental polar air mass has pushed up to the foothills, creating an environment supportive of thunderstorms that varies little with latitude from the Raton Mesa northward to the Laramie Mountains. By early afternoon, forecast soundings suggest this environment will consist of 1500-2500 J/kg of MLCAPE (higher toward the Mountains) with little convective inhibition, moderate straight-line vertical wind shear confined mostly in the 1-4 km layer (supportive of multicell to some transient supercell structures), and DCAPE of 1200-1500 J/kg. Given storm rotation and steep low-to-mid level lapse rates, severe hail is the main threat with these storms, but brief severe wind gusts are possible in the stronger downdrafts. Moderate low-level southeasterly upslope flow combined with relatively weak west-northwesterly to westerly flow at 500-300 mb suggests a slow south to southeast motion to the cells, thus limiting the eastward extent of the threat. The main uncertainty concerning the need for a Severe Thunderstorm Watch is the coverage of the hail/wind threat. The coverage of storms that mature and move into the foothills will be monitored in the next hour or so to better determine if a Watch will be needed. ..Coniglio/Guyer.. 08/21/2019 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...PUB...BOU...CYS...RIW... LAT...LON 42860625 42760567 41960518 40150447 39820440 38480387 37790355 37460341 37110354 37050408 37090466 37430506 38260552 39540598 40280617 41270651 42560648 42860625 Read more

SPC Day 2 Fire Weather Outlook

5 years 11 months ago
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0146 PM CDT Wed Aug 21 2019 Valid 221200Z - 231200Z Minor adjustments were made to ongoing elevated lines based on 12Z high resolution forecast guidance. However, no significant changes were made. See previous discussion below. ..Bentley.. 08/21/2019 .PREV DISCUSSION... /ISSUED 0143 AM CDT Wed Aug 21 2019/ ...Synopsis... An upper-level shortwave trough will continue to move east-northeast across the northern Intermountain West tomorrow. An associated surface cold front will continue to move south and east into the Great Basin and through much of the northern Rockies and northern California. With a pre-frontal surface pressure trough running parallel and ahead of the cold front, the surface pressure gradient will strengthen across the Intermountain West along and ahead of the cold front. Elevated conditions are expected from northern Arizona/southern Nevada stretching northeastward into central Wyoming along/ahead of the surface cold front. Southwest-westerly sustained surface winds of 15-20 mph and RH values of 8-20% are likely to develop during tomorrow afternoon and evening across this area. High clouds may drift into northern Arizona, which could limit the southern extent of the current elevated area. Elevated conditions are also likely to develop across central/eastern portions of the Snake River Plain and vicinity tomorrow afternoon. The cold front will have passed through the area, but daytime heating should warm temperatures and mix the boundary layer enough to result in west-southwest winds of 15-25 mph and RH values of 15-20%. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook

5 years 11 months ago
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0146 PM CDT Wed Aug 21 2019 Valid 221200Z - 231200Z Minor adjustments were made to ongoing elevated lines based on 12Z high resolution forecast guidance. However, no significant changes were made. See previous discussion below. ..Bentley.. 08/21/2019 .PREV DISCUSSION... /ISSUED 0143 AM CDT Wed Aug 21 2019/ ...Synopsis... An upper-level shortwave trough will continue to move east-northeast across the northern Intermountain West tomorrow. An associated surface cold front will continue to move south and east into the Great Basin and through much of the northern Rockies and northern California. With a pre-frontal surface pressure trough running parallel and ahead of the cold front, the surface pressure gradient will strengthen across the Intermountain West along and ahead of the cold front. Elevated conditions are expected from northern Arizona/southern Nevada stretching northeastward into central Wyoming along/ahead of the surface cold front. Southwest-westerly sustained surface winds of 15-20 mph and RH values of 8-20% are likely to develop during tomorrow afternoon and evening across this area. High clouds may drift into northern Arizona, which could limit the southern extent of the current elevated area. Elevated conditions are also likely to develop across central/eastern portions of the Snake River Plain and vicinity tomorrow afternoon. The cold front will have passed through the area, but daytime heating should warm temperatures and mix the boundary layer enough to result in west-southwest winds of 15-25 mph and RH values of 15-20%. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook

5 years 11 months ago
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0146 PM CDT Wed Aug 21 2019 Valid 221200Z - 231200Z Minor adjustments were made to ongoing elevated lines based on 12Z high resolution forecast guidance. However, no significant changes were made. See previous discussion below. ..Bentley.. 08/21/2019 .PREV DISCUSSION... /ISSUED 0143 AM CDT Wed Aug 21 2019/ ...Synopsis... An upper-level shortwave trough will continue to move east-northeast across the northern Intermountain West tomorrow. An associated surface cold front will continue to move south and east into the Great Basin and through much of the northern Rockies and northern California. With a pre-frontal surface pressure trough running parallel and ahead of the cold front, the surface pressure gradient will strengthen across the Intermountain West along and ahead of the cold front. Elevated conditions are expected from northern Arizona/southern Nevada stretching northeastward into central Wyoming along/ahead of the surface cold front. Southwest-westerly sustained surface winds of 15-20 mph and RH values of 8-20% are likely to develop during tomorrow afternoon and evening across this area. High clouds may drift into northern Arizona, which could limit the southern extent of the current elevated area. Elevated conditions are also likely to develop across central/eastern portions of the Snake River Plain and vicinity tomorrow afternoon. The cold front will have passed through the area, but daytime heating should warm temperatures and mix the boundary layer enough to result in west-southwest winds of 15-25 mph and RH values of 15-20%. ...Please see www.spc.noaa.gov/fire for graphic product... Read more