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SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0757 AM CDT Fri Sep 06 2019 Valid 061300Z - 071200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING OVER PARTS OF THE NORTHERN INTERMOUNTAIN REGION...NORTHERN/CENTRAL ROCKIES AND ADJACENT HIGH PLAINS... ...SUMMARY... Isolated severe thunderstorm winds and hail are possible this afternoon and evening over parts of the northern Intermountain region, northern/central Rockies and adjacent High Plains. ...Synopsis... In mid/upper levels, an initially strong anticyclone centered over the south-central Rockies will shift southwestward and weaken as a strong shortwave trough crosses the northern Rockies. That trough -- now evident in moisture-channel imagery over western OR and northern CA -- is progged to overtake/absorb lesser vorticity lobes initially to its east across eastern OR/ID. The combined, somewhat stronger perturbation will reach the MT/ID border region and southern ID by 00Z. Thereafter, the trough will pivot eastward and east-southeastward, reaching central MT, western WY and northwestern CO by 12Z. Meanwhile, farther east, shortwave troughs now over the upper Great Lakes and northern MB will move southeastward across the Mid-Atlantic and upper Great Lakes, respectively. In response, Hurricane Dorian has commenced accelerating northeastward over/off the Outer Banks, and should eject away from the Tidewater region through the remainder of the period, per NHC forecasts. With the most thermodynamically and kinematically favorable sector for supercellular tornadoes shifting offshore, and forecast to stay southeast of the Cape Cod/Martha's Vineyard region tonight, unconditional overland tornado probabilities have been dropped. Otherwise, the surface analysis showed a low near GRB with occluded front to southeastern IA, and slow-moving cold front to a weak frontal-wave/lee low over western KS, then extending across parts of southeastern CO. The low should move southeastward across OH overnight and become poorly defined in the broader field of low pressure surrounding Dorian. Meanwhile the front should cross the Ohio Valley and stall across the southern KS/northern OK/ southeastern CO corridor. ...Northern Rockies/Intermountain region to Front Range/central High Plains... Widely scattered to scattered thunderstorms are expected to develop this afternoon into evening in three primary regimes, described below from west to east, each offering isolated severe gusts/hail, with enough spatial overlap to result in a unified outlook area: 1. A "cold-core" regime near the midlevel/500-mb thermal trough, from eastern OR across much of southern ID, potentially forming a quasi-linear band of strong/isolated severe convection over ID before weakening tonight in western WY where regime 2 below will have produced enough convection to stabilize the air mass. Diurnal heating and midlevel cooling should overlap well, steepening low/ middle-level lapse rates considerably, atop 50s F low-elevation surface dew points. This should result in MLCAPE 1000-1500 J/kg atop a well-mixed boundary layer supporting strong/locally severe gusts and survival of hail to ground level. Organization should be tempered somewhat by weakening deep-layer flow with time and proximity to the mid/upper trough, and related lack of shear. However, a conditional cold-pool aggregation potential exists, especially across parts of the Snake River Plain and southern mountains west of I-15. 2. A band of relatively maximized deep-layer ascent shifting eastward from southeastern ID and northern UT across western/central WY. A combination of lift from large-scale DCVA/cooling aloft, frontal forcing near a low-level baroclinic zone preceding that trough, and pre-frontal warm advection will support convection in this area. Buoyancy should be less in both coverage and magnitude than in regime 1, with MLCAPE mainly around 500 J/kg. Still, localized well-mixed boundary layers and marginal deep shear will promote a few strong-severe cells in the broader convective plume. 3. Heating of higher terrain, favorable low-level moisture, and resultant weak MLCINH should foster convection initiation this afternoon over the Front Range, Laramie Range, adjacent foothills, and perhaps the Bighorns. Activity then should move eastward across a diabatically destabilized strip of the central High Plains, offering damaging gusts and isolated hail before weakening. Strong surface heating and deep, strongly mixed boundary layers will support isolated severe potential with this activity before it weakens this evening in a stabilizing boundary layer, at lower elevations. ..Edwards/Smith.. 09/06/2019 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0757 AM CDT Fri Sep 06 2019 Valid 061300Z - 071200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING OVER PARTS OF THE NORTHERN INTERMOUNTAIN REGION...NORTHERN/CENTRAL ROCKIES AND ADJACENT HIGH PLAINS... ...SUMMARY... Isolated severe thunderstorm winds and hail are possible this afternoon and evening over parts of the northern Intermountain region, northern/central Rockies and adjacent High Plains. ...Synopsis... In mid/upper levels, an initially strong anticyclone centered over the south-central Rockies will shift southwestward and weaken as a strong shortwave trough crosses the northern Rockies. That trough -- now evident in moisture-channel imagery over western OR and northern CA -- is progged to overtake/absorb lesser vorticity lobes initially to its east across eastern OR/ID. The combined, somewhat stronger perturbation will reach the MT/ID border region and southern ID by 00Z. Thereafter, the trough will pivot eastward and east-southeastward, reaching central MT, western WY and northwestern CO by 12Z. Meanwhile, farther east, shortwave troughs now over the upper Great Lakes and northern MB will move southeastward across the Mid-Atlantic and upper Great Lakes, respectively. In response, Hurricane Dorian has commenced accelerating northeastward over/off the Outer Banks, and should eject away from the Tidewater region through the remainder of the period, per NHC forecasts. With the most thermodynamically and kinematically favorable sector for supercellular tornadoes shifting offshore, and forecast to stay southeast of the Cape Cod/Martha's Vineyard region tonight, unconditional overland tornado probabilities have been dropped. Otherwise, the surface analysis showed a low near GRB with occluded front to southeastern IA, and slow-moving cold front to a weak frontal-wave/lee low over western KS, then extending across parts of southeastern CO. The low should move southeastward across OH overnight and become poorly defined in the broader field of low pressure surrounding Dorian. Meanwhile the front should cross the Ohio Valley and stall across the southern KS/northern OK/ southeastern CO corridor. ...Northern Rockies/Intermountain region to Front Range/central High Plains... Widely scattered to scattered thunderstorms are expected to develop this afternoon into evening in three primary regimes, described below from west to east, each offering isolated severe gusts/hail, with enough spatial overlap to result in a unified outlook area: 1. A "cold-core" regime near the midlevel/500-mb thermal trough, from eastern OR across much of southern ID, potentially forming a quasi-linear band of strong/isolated severe convection over ID before weakening tonight in western WY where regime 2 below will have produced enough convection to stabilize the air mass. Diurnal heating and midlevel cooling should overlap well, steepening low/ middle-level lapse rates considerably, atop 50s F low-elevation surface dew points. This should result in MLCAPE 1000-1500 J/kg atop a well-mixed boundary layer supporting strong/locally severe gusts and survival of hail to ground level. Organization should be tempered somewhat by weakening deep-layer flow with time and proximity to the mid/upper trough, and related lack of shear. However, a conditional cold-pool aggregation potential exists, especially across parts of the Snake River Plain and southern mountains west of I-15. 2. A band of relatively maximized deep-layer ascent shifting eastward from southeastern ID and northern UT across western/central WY. A combination of lift from large-scale DCVA/cooling aloft, frontal forcing near a low-level baroclinic zone preceding that trough, and pre-frontal warm advection will support convection in this area. Buoyancy should be less in both coverage and magnitude than in regime 1, with MLCAPE mainly around 500 J/kg. Still, localized well-mixed boundary layers and marginal deep shear will promote a few strong-severe cells in the broader convective plume. 3. Heating of higher terrain, favorable low-level moisture, and resultant weak MLCINH should foster convection initiation this afternoon over the Front Range, Laramie Range, adjacent foothills, and perhaps the Bighorns. Activity then should move eastward across a diabatically destabilized strip of the central High Plains, offering damaging gusts and isolated hail before weakening. Strong surface heating and deep, strongly mixed boundary layers will support isolated severe potential with this activity before it weakens this evening in a stabilizing boundary layer, at lower elevations. ..Edwards/Smith.. 09/06/2019 Read more

122
ABPZ20 KNHC 061131
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
500 AM PDT Fri Sep 6 2019

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

The National Hurricane Center is issuing advisories on Hurricane
Juliette, located several hundred miles west of the southern tip of
the Baja California peninsula.

Tropical cyclone formation is not expected during the next 5 days.

$$
Forecaster Brown

5-Day Uncertainty Track last updated Fri, 06 Sep 2019 11:23:40 GMT


Wind Speed Probabilities last updated Fri, 06 Sep 2019 11:23:41 GMT

Issued at 1100 PM HST Thu Sep 05 2019 000 WTPZ41 KNHC 060925 CCA TCDEP1 Hurricane Juliette Discussion Number 21...Corrected NWS National Hurricane Center Miami FL EP112019 1100 PM HST Thu Sep 05 2019 Corrected motion in third paragraph. This evening's satellite presentation is showing a considerable amount of deterioration of Juliette's inner core. The eastern portion of the eyewall has eroded, cloud tops have continue to warm, and it appears as though some drier mid-level air is intruding from the northwest. Subjective satellite intensity estimates from TAFB and SAB, and the UW-CIMSS Objective T-number supports lowering the initial intensity to 70 kt. Although the upper-level winds are expected to remain in a favorable pattern during the next couple days, the hurricane will be moving over decreasing sea surface temperatures and into increasingly stable thermodynamic conditions. Subsequently, gradual weakening should continue through the entire forecast period, and Juliette is expected to become a remnant low in 3 days, or less. The intensity forecast is basically a compromise of the NOAA HFIP HCCA and the global models beyond the 48-hour period. The initial motion continues to be northwestward, or 305/9 kt. A mid-level ridge extending from the southwestern United States over the eastern Pacific should induce a west-northwestward turn on Friday, and this general motion should continue through the next couple of days. Toward the end of the period, a westward motion should commence as Juliette degenerates into a vertically shallow depression, and eventually, a remnant low, and becomes steered by the low-level tradewind flow. The track forecast is an update of the previous advisory and sides with the TVCE model consensus. FORECAST POSITIONS AND MAX WINDS INIT 06/0900Z 22.4N 122.7W 70 KT 80 MPH 12H 06/1800Z 23.0N 124.2W 60 KT 70 MPH 24H 07/0600Z 23.6N 126.4W 50 KT 60 MPH 36H 07/1800Z 23.8N 128.5W 40 KT 45 MPH 48H 08/0600Z 23.8N 130.6W 35 KT 40 MPH...POST-TROPICAL 72H 09/0600Z 23.4N 135.0W 25 KT 30 MPH...POST-TROP/REMNT LOW 96H 10/0600Z 23.4N 138.2W 25 KT 30 MPH...POST-TROP/REMNT LOW 120H 11/0600Z 23.8N 141.7W 20 KT 25 MPH...POST-TROP/REMNT LOW $$ Forecaster Roberts

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0358 AM CDT Fri Sep 06 2019 Valid 091200Z - 141200Z ...DISCUSSION... ...Monday/Day 4 to Wednesday/Day 6... The medium-range models are in good agreement on Monday with a shortwave trough and an associated cold front over the northern Plains. The models suggest that thunderstorm development will be possible ahead of the front in parts of Nebraska and the eastern Dakotas on Monday afternoon. Forecast instability and deep-layer shear may be enough for an isolated severe threat. On Tuesday, the models develop an upper-level trough in the western U.S. as a shortwave ridge moves into the northern Plains. Thunderstorms will be possible on Tuesday along a front that is forecast to be from northern parts of the central Plains eastward into the southern Great Lakes region. The models remain in reasonable agreement on Wednesday with an upper-level trough over the western states and southwest mid-level flow in the Great Plains. Thunderstorms will again be possible across parts of the central and northern Plains where the ECMWF, GFS and UKMET show a surface low and a moist airmass. An isolated severe threat will be possible in parts of Nebraska and South Dakota in areas that destabilize the most. ...Thursday/Day 7 to Friday/Day 8... On Thursday and Friday, model solutions are somewhat in agreement concerning an upper-level trough that is forecast to move across the north-central U.S. Both the GFS and ECMWF show a moist and unstable airmass located across the mid Missouri and upper Mississippi Valleys Thursday afternoon. A severe threat will be possible ahead of the upper-level trough in parts of the eastern Dakotas and Minnesota. The potential for severe thunderstorms is forecast to shift into the Great Lakes on Friday as a cold front moves southeastward across the central U.S. Although a conditional severe threat will be possible throughout the day 4 to 8 period across parts of the central and northern U.S, predictability is too low to outlook a threat area at this time. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0358 AM CDT Fri Sep 06 2019 Valid 091200Z - 141200Z ...DISCUSSION... ...Monday/Day 4 to Wednesday/Day 6... The medium-range models are in good agreement on Monday with a shortwave trough and an associated cold front over the northern Plains. The models suggest that thunderstorm development will be possible ahead of the front in parts of Nebraska and the eastern Dakotas on Monday afternoon. Forecast instability and deep-layer shear may be enough for an isolated severe threat. On Tuesday, the models develop an upper-level trough in the western U.S. as a shortwave ridge moves into the northern Plains. Thunderstorms will be possible on Tuesday along a front that is forecast to be from northern parts of the central Plains eastward into the southern Great Lakes region. The models remain in reasonable agreement on Wednesday with an upper-level trough over the western states and southwest mid-level flow in the Great Plains. Thunderstorms will again be possible across parts of the central and northern Plains where the ECMWF, GFS and UKMET show a surface low and a moist airmass. An isolated severe threat will be possible in parts of Nebraska and South Dakota in areas that destabilize the most. ...Thursday/Day 7 to Friday/Day 8... On Thursday and Friday, model solutions are somewhat in agreement concerning an upper-level trough that is forecast to move across the north-central U.S. Both the GFS and ECMWF show a moist and unstable airmass located across the mid Missouri and upper Mississippi Valleys Thursday afternoon. A severe threat will be possible ahead of the upper-level trough in parts of the eastern Dakotas and Minnesota. The potential for severe thunderstorms is forecast to shift into the Great Lakes on Friday as a cold front moves southeastward across the central U.S. Although a conditional severe threat will be possible throughout the day 4 to 8 period across parts of the central and northern U.S, predictability is too low to outlook a threat area at this time. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0358 AM CDT Fri Sep 06 2019 Valid 091200Z - 141200Z ...DISCUSSION... ...Monday/Day 4 to Wednesday/Day 6... The medium-range models are in good agreement on Monday with a shortwave trough and an associated cold front over the northern Plains. The models suggest that thunderstorm development will be possible ahead of the front in parts of Nebraska and the eastern Dakotas on Monday afternoon. Forecast instability and deep-layer shear may be enough for an isolated severe threat. On Tuesday, the models develop an upper-level trough in the western U.S. as a shortwave ridge moves into the northern Plains. Thunderstorms will be possible on Tuesday along a front that is forecast to be from northern parts of the central Plains eastward into the southern Great Lakes region. The models remain in reasonable agreement on Wednesday with an upper-level trough over the western states and southwest mid-level flow in the Great Plains. Thunderstorms will again be possible across parts of the central and northern Plains where the ECMWF, GFS and UKMET show a surface low and a moist airmass. An isolated severe threat will be possible in parts of Nebraska and South Dakota in areas that destabilize the most. ...Thursday/Day 7 to Friday/Day 8... On Thursday and Friday, model solutions are somewhat in agreement concerning an upper-level trough that is forecast to move across the north-central U.S. Both the GFS and ECMWF show a moist and unstable airmass located across the mid Missouri and upper Mississippi Valleys Thursday afternoon. A severe threat will be possible ahead of the upper-level trough in parts of the eastern Dakotas and Minnesota. The potential for severe thunderstorms is forecast to shift into the Great Lakes on Friday as a cold front moves southeastward across the central U.S. Although a conditional severe threat will be possible throughout the day 4 to 8 period across parts of the central and northern U.S, predictability is too low to outlook a threat area at this time. Read more

Issued at 0900 UTC FRI SEP 06 2019 000 FOPZ11 KNHC 060851 PWSEP1 HURRICANE JULIETTE WIND SPEED PROBABILITIES NUMBER 21 NWS NATIONAL HURRICANE CENTER MIAMI FL EP112019 0900 UTC FRI SEP 06 2019 AT 0900Z THE CENTER OF HURRICANE JULIETTE WAS LOCATED NEAR LATITUDE 22.4 NORTH...LONGITUDE 122.7 WEST WITH MAXIMUM SUSTAINED WINDS NEAR 70 KTS...80 MPH...130 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 06Z FRI 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 06Z FRI 18Z FRI 06Z SAT 18Z SAT 06Z SUN 06Z MON 06Z TUE PERIODS TO TO TO TO TO TO TO 18Z FRI 06Z SAT 18Z SAT 06Z SUN 06Z MON 06Z TUE 06Z WED FORECAST HOUR (12) (24) (36) (48) (72) (96) (120) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - LOCATION KT 20N 125W 34 2 2( 4) 1( 5) X( 5) X( 5) X( 5) X( 5) 25N 125W 34 7 13(20) 1(21) X(21) X(21) X(21) X(21) 20N 130W 34 X 1( 1) 1( 2) 1( 3) X( 3) X( 3) X( 3) 25N 130W 34 X 2( 2) 6( 8) 13(21) 1(22) X(22) X(22) 25N 130W 50 X X( X) X( X) 3( 3) X( 3) X( 3) X( 3) 20N 135W 34 X X( X) X( X) X( X) 2( 2) 1( 3) X( 3) 25N 135W 34 X X( X) X( X) 1( 1) 6( 7) 2( 9) X( 9) 25N 140W 34 X X( X) X( X) X( X) X( X) 2( 2) 2( 4) $$ FORECASTER ROBERTS

Issued at 1100 PM HST Thu Sep 05 2019 608 WTPZ31 KNHC 060851 TCPEP1 BULLETIN Hurricane Juliette Advisory Number 21 NWS National Hurricane Center Miami FL EP112019 1100 PM HST Thu Sep 05 2019 ...JULIETTE ON THE DECLINE... ...EXPECTED TO BECOME A TROPICAL STORM ON FRIDAY... SUMMARY OF 1100 PM HST...0900 UTC...INFORMATION ----------------------------------------------- LOCATION...22.4N 122.7W ABOUT 815 MI...1315 KM W OF THE SOUTHERN TIP OF BAJA CALIFORNIA MAXIMUM SUSTAINED WINDS...80 MPH...130 KM/H PRESENT MOVEMENT...NW OR 305 DEGREES AT 10 MPH...17 KM/H MINIMUM CENTRAL PRESSURE...984 MB...29.06 INCHES WATCHES AND WARNINGS -------------------- There are no coastal watches or warnings in effect. DISCUSSION AND OUTLOOK ---------------------- At 1100 PM HST (0900 UTC), the center of Hurricane Juliette was located near latitude 22.4 North, longitude 122.7 West. Juliette is moving toward the northwest near 10 mph (17 km/h). A motion toward the west-northwest should begin later tonight or Friday. A turn toward the west is forecast on Saturday and a general westward motion should continue through the weekend. Maximum sustained winds have decreased to near 80 mph (130 km/h) with higher gusts. Additional weakening is forecast during the next few days, and Juliette is expected to become a tropical storm by Friday night, and degenerate into a remnant low on Sunday. Hurricane-force winds extend outward up to 35 miles (55 km) from the center and tropical-storm-force winds extend outward up to 105 miles (165 km). The estimated minimum central pressure is 984 mb (29.06 inches). HAZARDS AFFECTING LAND ---------------------- None. NEXT ADVISORY ------------- Next complete advisory at 500 AM HST. $$ Forecaster Roberts

...JULIETTE ON THE DECLINE... ...EXPECTED TO BECOME A TROPICAL STORM ON FRIDAY... As of 11:00 PM HST Thu Sep 5 the center of Juliette was located near 22.4, -122.7 with movement NW at 10 mph. The minimum central pressure was 984 mb with maximum sustained winds of about 80 mph.

Issued at 0900 UTC FRI SEP 06 2019 000 WTPZ21 KNHC 060851 TCMEP1 HURRICANE JULIETTE FORECAST/ADVISORY NUMBER 21 NWS NATIONAL HURRICANE CENTER MIAMI FL EP112019 0900 UTC FRI SEP 06 2019 THERE ARE NO COASTAL WATCHES OR WARNINGS IN EFFECT. HURRICANE CENTER LOCATED NEAR 22.4N 122.7W AT 06/0900Z POSITION ACCURATE WITHIN 20 NM PRESENT MOVEMENT TOWARD THE NORTHWEST OR 305 DEGREES AT 9 KT ESTIMATED MINIMUM CENTRAL PRESSURE 984 MB MAX SUSTAINED WINDS 70 KT WITH GUSTS TO 85 KT. 64 KT....... 30NE 25SE 20SW 30NW. 50 KT....... 40NE 40SE 30SW 40NW. 34 KT....... 90NE 90SE 90SW 90NW. 12 FT SEAS..150NE 120SE 90SW 120NW. 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 22.4N 122.7W AT 06/0900Z AT 06/0600Z CENTER WAS LOCATED NEAR 22.1N 122.2W FORECAST VALID 06/1800Z 23.0N 124.2W MAX WIND 60 KT...GUSTS 75 KT. 50 KT... 40NE 40SE 30SW 40NW. 34 KT... 90NE 80SE 80SW 90NW. FORECAST VALID 07/0600Z 23.6N 126.4W MAX WIND 50 KT...GUSTS 60 KT. 50 KT... 30NE 20SE 0SW 30NW. 34 KT... 70NE 70SE 50SW 70NW. FORECAST VALID 07/1800Z 23.8N 128.5W MAX WIND 40 KT...GUSTS 50 KT. 34 KT... 60NE 60SE 30SW 60NW. FORECAST VALID 08/0600Z 23.8N 130.6W...POST-TROPICAL MAX WIND 35 KT...GUSTS 45 KT. 34 KT... 40NE 0SE 0SW 40NW. FORECAST VALID 09/0600Z 23.4N 135.0W...POST-TROP/REMNT LOW MAX WIND 25 KT...GUSTS 35 KT. 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 10/0600Z 23.4N 138.2W...POST-TROP/REMNT LOW MAX WIND 25 KT...GUSTS 35 KT. OUTLOOK VALID 11/0600Z 23.8N 141.7W...POST-TROP/REMNT LOW MAX WIND 20 KT...GUSTS 30 KT. REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 22.4N 122.7W NEXT ADVISORY AT 06/1500Z $$ FORECASTER ROBERTS

WW 0637 Status Updates
STATUS REPORT ON WW 637 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 55 NE HSE TO 25 E ECG TO 15 WSW ECG TO 15 W ORF. ..SMITH..09/06/19 ATTN...WFO...MHX...AKQ... STATUS REPORT FOR WT 637 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS NCC029-053-139-143-060840- NC . NORTH CAROLINA COUNTIES INCLUDED ARE CAMDEN CURRITUCK PASQUOTANK PERQUIMANS VAC550-710-740-810-060840- VA . VIRGINIA COUNTIES INCLUDED ARE VIRGINIA INDEPENDENT CITIES INCLUDED ARE CHESAPEAKE NORFOLK PORTSMOUTH VIRGINIA BEACH ANZ633-634-656-658-060840- Read more

WW 637 TORNADO NC VA CW 052215Z - 061100Z
URGENT - IMMEDIATE BROADCAST REQUESTED Tornado Watch Number 637 NWS Storm Prediction Center Norman OK 615 PM EDT Thu Sep 5 2019 The NWS Storm Prediction Center has issued a * Tornado Watch for portions of Eastern North Carolina Extreme southeastern Virginia Coastal Waters * Effective this Thursday night and Friday morning from 615 PM until 700 AM EDT. * Primary threats include... A few tornadoes likely SUMMARY...Threat for occasional supercells with tornadoes will persist through tonight within the outer northeastern rain bands of hurricane Dorian. The tornado watch area is approximately along and 65 statute miles east and west of a line from 60 miles northeast of Elizabeth City NC to 25 miles south southeast of New Bern NC. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU7). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Tornado Watch means conditions are favorable for tornadoes and severe thunderstorms in and close to the watch area. Persons in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings. && OTHER WATCH INFORMATION...This tornado watch replaces tornado watch number 636. Watch number 636 will not be in effect after 615 PM EDT. AVIATION...Tornadoes and a few severe thunderstorms with hail surface and aloft to 0.5 inches. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 10045. ...Thompson Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0202 AM CDT Fri Sep 06 2019 Valid 081200Z - 091200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL PLAINS... ...SUMMARY... Marginally severe thunderstorms with strong wind gusts and hail will be possible across parts of the central High Plains Sunday afternoon and evening. ...Central High Plains... An upper-level trough is forecast to move into the central and northern Rockies on Sunday as a shortwave ridge moves across the central and northern Plains. A lee surface trough is forecast to develop in the central High Plains to the east of the Front Range. Surface dewpoints may be able to reach the lower 60s F in parts of eastern Colorado due to upslope easterly flow. This may allow for a pocket of moderate instability to develop by afternoon. Thunderstorms are forecast to develop in the higher terrain and move eastward into the central High Plains during the afternoon. The instability combined with steep mid-level lapse rates and moderate deep-layer shear should be enough for a marginal severe threat. A few of the stronger cells could produce hail and marginally severe wind gusts. ..Broyles.. 09/06/2019 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0202 AM CDT Fri Sep 06 2019 Valid 081200Z - 091200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL PLAINS... ...SUMMARY... Marginally severe thunderstorms with strong wind gusts and hail will be possible across parts of the central High Plains Sunday afternoon and evening. ...Central High Plains... An upper-level trough is forecast to move into the central and northern Rockies on Sunday as a shortwave ridge moves across the central and northern Plains. A lee surface trough is forecast to develop in the central High Plains to the east of the Front Range. Surface dewpoints may be able to reach the lower 60s F in parts of eastern Colorado due to upslope easterly flow. This may allow for a pocket of moderate instability to develop by afternoon. Thunderstorms are forecast to develop in the higher terrain and move eastward into the central High Plains during the afternoon. The instability combined with steep mid-level lapse rates and moderate deep-layer shear should be enough for a marginal severe threat. A few of the stronger cells could produce hail and marginally severe wind gusts. ..Broyles.. 09/06/2019 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0202 AM CDT Fri Sep 06 2019 Valid 081200Z - 091200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL PLAINS... ...SUMMARY... Marginally severe thunderstorms with strong wind gusts and hail will be possible across parts of the central High Plains Sunday afternoon and evening. ...Central High Plains... An upper-level trough is forecast to move into the central and northern Rockies on Sunday as a shortwave ridge moves across the central and northern Plains. A lee surface trough is forecast to develop in the central High Plains to the east of the Front Range. Surface dewpoints may be able to reach the lower 60s F in parts of eastern Colorado due to upslope easterly flow. This may allow for a pocket of moderate instability to develop by afternoon. Thunderstorms are forecast to develop in the higher terrain and move eastward into the central High Plains during the afternoon. The instability combined with steep mid-level lapse rates and moderate deep-layer shear should be enough for a marginal severe threat. A few of the stronger cells could produce hail and marginally severe wind gusts. ..Broyles.. 09/06/2019 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0202 AM CDT Fri Sep 06 2019 Valid 081200Z - 091200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL PLAINS... ...SUMMARY... Marginally severe thunderstorms with strong wind gusts and hail will be possible across parts of the central High Plains Sunday afternoon and evening. ...Central High Plains... An upper-level trough is forecast to move into the central and northern Rockies on Sunday as a shortwave ridge moves across the central and northern Plains. A lee surface trough is forecast to develop in the central High Plains to the east of the Front Range. Surface dewpoints may be able to reach the lower 60s F in parts of eastern Colorado due to upslope easterly flow. This may allow for a pocket of moderate instability to develop by afternoon. Thunderstorms are forecast to develop in the higher terrain and move eastward into the central High Plains during the afternoon. The instability combined with steep mid-level lapse rates and moderate deep-layer shear should be enough for a marginal severe threat. A few of the stronger cells could produce hail and marginally severe wind gusts. ..Broyles.. 09/06/2019 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0202 AM CDT Fri Sep 06 2019 Valid 071200Z - 081200Z ...NO CRITICAL AREAS... ...Synopsis... A negatively tilted mid-level shortwave trough will deepen across the far western CONUS throughout the Day 2/Saturday period. A surface trough will become established across the Great Basin region. As such, locally dry, breezy conditions may be observed across far western portions of the Great Basin, mainly along the lee of the Sierra. These conditions are expected to brief and patchy enough to preclude an elevated delineation. Ahead of the surface and mid-level trough axes, deep-layer ascent may encourage isolated to scattered thunderstorms across parts of northern Nevada. Nonetheless, recent accumulated rainfall from previous thunderstorm events raises concerns as to how receptive fuels will be in this area to fire spread, especially given that the forecast Day 2 storms will be predominantly wet in nature, precluding an isolated dry thunderstorm delineation at this time. Otherwise, relatively quiescent fire weather conditions are expected across the western CONUS. ..Squitieri.. 09/06/2019 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0202 AM CDT Fri Sep 06 2019 Valid 071200Z - 081200Z ...NO CRITICAL AREAS... ...Synopsis... A negatively tilted mid-level shortwave trough will deepen across the far western CONUS throughout the Day 2/Saturday period. A surface trough will become established across the Great Basin region. As such, locally dry, breezy conditions may be observed across far western portions of the Great Basin, mainly along the lee of the Sierra. These conditions are expected to brief and patchy enough to preclude an elevated delineation. Ahead of the surface and mid-level trough axes, deep-layer ascent may encourage isolated to scattered thunderstorms across parts of northern Nevada. Nonetheless, recent accumulated rainfall from previous thunderstorm events raises concerns as to how receptive fuels will be in this area to fire spread, especially given that the forecast Day 2 storms will be predominantly wet in nature, precluding an isolated dry thunderstorm delineation at this time. Otherwise, relatively quiescent fire weather conditions are expected across the western CONUS. ..Squitieri.. 09/06/2019 ...Please see www.spc.noaa.gov/fire for graphic product... Read more