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Issued at 900 AM MDT Mon Sep 02 2019 000 WTPZ41 KNHC 021441 TCDEP1 Tropical Storm Juliette Discussion Number 6 NWS National Hurricane Center Miami FL EP112019 900 AM MDT Mon Sep 02 2019 Juliette is nearing hurricane strength. An increase in deep convection that was noted with the previous advisory has persisted, and recent microwave data shows that the cyclone has developed a well-defined inner-core. Given the observed increase in Juliette's organization, the initial intensity has been increased to 60 kt, which is supported by the latest UW-CIMSS ADT and SATCON fixes. Juliette is forecast to quickly strengthen today, and rapid intensification is a real possibility during the next 24 hours or so given the seemingly favorable environment and the presence of an low- to mid-level eye in recent microwave data. Beyond 48 h, the cyclone should begin to weaken as it moves over cooler SSTs and encounters a drier surrounding environment. The NHC intensity forecast is near the multi-model consensus from 72 h through the end of the period, but there is a fair amount of uncertainty as to how quickly Juliette will weaken since it will be moving along a sharp SST gradient. A track farther north than the NHC forecast would likely cause Juliette to weaken faster than anticipated, while a farther south track could allow it to maintain its strength for longer. Very little change was made to the track forecast. A deep-layer ridge to the northeast of Juliette should keep it on a generally west-northwestward to northwestward heading for the next 3 or 4 days days. The track guidance is particularly tightly clustered through that period and confidence in the forecast is high. The ridge could amplify by day 5 and cause Juliette to turn westward, as shown most notably by the ECMWF, though confidence is a little lower at that time. The NHC forecast is very near TVCE and HCCA at all times and lies near the middle of the guidance envelope. FORECAST POSITIONS AND MAX WINDS INIT 02/1500Z 16.7N 112.6W 60 KT 70 MPH 12H 03/0000Z 17.6N 114.0W 75 KT 85 MPH 24H 03/1200Z 18.4N 115.5W 85 KT 100 MPH 36H 04/0000Z 18.9N 116.8W 90 KT 105 MPH 48H 04/1200Z 19.4N 118.2W 90 KT 105 MPH 72H 05/1200Z 20.6N 121.8W 70 KT 80 MPH 96H 06/1200Z 22.5N 126.0W 55 KT 65 MPH 120H 07/1200Z 23.5N 130.5W 45 KT 50 MPH $$ Forecaster Zelinsky

Issued at 900 AM MDT Mon Sep 02 2019 000 WTPZ31 KNHC 021441 TCPEP1 BULLETIN Tropical Storm Juliette Advisory Number 6 NWS National Hurricane Center Miami FL EP112019 900 AM MDT Mon Sep 02 2019 ...JULIETTE WILL LIKELY BECOME A HURRICANE LATER TODAY... SUMMARY OF 900 AM MDT...1500 UTC...INFORMATION ---------------------------------------------- LOCATION...16.7N 112.6W ABOUT 465 MI...745 KM SSW OF THE SOUTHERN TIP OF BAJA CALIFORNIA MAXIMUM SUSTAINED WINDS...70 MPH...110 KM/H PRESENT MOVEMENT...NW OR 305 DEGREES AT 14 MPH...22 KM/H MINIMUM CENTRAL PRESSURE...994 MB...29.36 INCHES WATCHES AND WARNINGS -------------------- There are no coastal watches or warnings in effect. DISCUSSION AND OUTLOOK ---------------------- At 900 AM MDT (1500 UTC), the center of Tropical Storm Juliette was located near latitude 16.7 North, longitude 112.6 West. Juliette is moving toward the northwest near 14 mph (22 km/h). A west- northwestward motion with some decrease in forward speed is forecast for the next several days. Maximum sustained winds are near 70 mph (110 km/h) with higher gusts. Strengthening is anticipated, and Juliette is forecast to become a hurricane later today, with further strengthening anticipated on Tuesday. Tropical-storm-force winds extend outward up to 150 miles (240 km) from the center. The estimated minimum central pressure is 994 mb (29.36 inches). HAZARDS AFFECTING LAND ---------------------- None. NEXT ADVISORY ------------- Next complete advisory at 300 PM MDT. $$ Forecaster Zelinsky

...JULIETTE WILL LIKELY BECOME A HURRICANE LATER TODAY... As of 9:00 AM MDT Mon Sep 2 the center of Juliette was located near 16.7, -112.6 with movement NW at 14 mph. The minimum central pressure was 994 mb with maximum sustained winds of about 70 mph.

Issued at 1500 UTC MON SEP 02 2019 000 FOPZ11 KNHC 021441 PWSEP1 TROPICAL STORM JULIETTE WIND SPEED PROBABILITIES NUMBER 6 NWS NATIONAL HURRICANE CENTER MIAMI FL EP112019 1500 UTC MON SEP 02 2019 AT 1500Z THE CENTER OF TROPICAL STORM JULIETTE WAS LOCATED NEAR LATITUDE 16.7 NORTH...LONGITUDE 112.6 WEST WITH MAXIMUM SUSTAINED WINDS NEAR 60 KTS...70 MPH...110 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 12Z MON 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 12Z MON 00Z TUE 12Z TUE 00Z WED 12Z WED 12Z THU 12Z FRI PERIODS TO TO TO TO TO TO TO 00Z TUE 12Z TUE 00Z WED 12Z WED 12Z THU 12Z FRI 12Z SAT FORECAST HOUR (12) (24) (36) (48) (72) (96) (120) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - LOCATION KT 20N 110W 34 2 1( 3) X( 3) X( 3) X( 3) X( 3) X( 3) ISLA SOCORRO 34 4 3( 7) 1( 8) X( 8) X( 8) X( 8) X( 8) ISLA CLARION 34 78 21(99) X(99) X(99) X(99) X(99) X(99) ISLA CLARION 50 15 71(86) 1(87) 1(88) X(88) X(88) X(88) ISLA CLARION 64 2 58(60) 1(61) X(61) X(61) X(61) X(61) 15N 115W 34 3 3( 6) 3( 9) 1(10) X(10) X(10) X(10) 20N 115W 34 6 49(55) 12(67) 2(69) 1(70) X(70) X(70) 20N 115W 50 1 5( 6) 4(10) 1(11) X(11) X(11) X(11) 20N 115W 64 X 1( 1) 1( 2) X( 2) X( 2) X( 2) X( 2) 15N 120W 34 X X( X) 2( 2) 2( 4) 3( 7) X( 7) X( 7) 20N 120W 34 X 2( 2) 6( 8) 32(40) 49(89) 1(90) X(90) 20N 120W 50 X X( X) X( X) 6( 6) 53(59) 1(60) X(60) 20N 120W 64 X X( X) X( X) 1( 1) 33(34) 1(35) X(35) 25N 120W 34 X X( X) X( X) 1( 1) 4( 5) 2( 7) X( 7) 20N 125W 34 X X( X) X( X) X( X) 9( 9) 26(35) 1(36) 20N 125W 50 X X( X) X( X) X( X) 1( 1) 9(10) X(10) 20N 125W 64 X X( X) X( X) X( X) X( X) 3( 3) X( 3) 25N 125W 34 X X( X) X( X) X( X) 1( 1) 13(14) 3(17) 25N 125W 50 X X( X) X( X) X( X) X( X) 2( 2) 1( 3) 20N 130W 34 X X( X) X( X) X( X) X( X) 3( 3) 7(10) 25N 130W 34 X X( X) X( X) X( X) X( X) 2( 2) 16(18) 25N 130W 50 X X( X) X( X) X( X) X( X) X( X) 3( 3) $$ FORECASTER ZELINSKY

Issued at 1500 UTC MON SEP 02 2019 051 WTPZ21 KNHC 021440 TCMEP1 TROPICAL STORM JULIETTE FORECAST/ADVISORY NUMBER 6 NWS NATIONAL HURRICANE CENTER MIAMI FL EP112019 1500 UTC MON SEP 02 2019 THERE ARE NO COASTAL WATCHES OR WARNINGS IN EFFECT. TROPICAL STORM CENTER LOCATED NEAR 16.7N 112.6W AT 02/1500Z POSITION ACCURATE WITHIN 25 NM PRESENT MOVEMENT TOWARD THE NORTHWEST OR 305 DEGREES AT 12 KT ESTIMATED MINIMUM CENTRAL PRESSURE 994 MB MAX SUSTAINED WINDS 60 KT WITH GUSTS TO 75 KT. 50 KT....... 50NE 30SE 0SW 40NW. 34 KT.......130NE 70SE 30SW 80NW. 12 FT SEAS..180NE 150SE 60SW 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 16.7N 112.6W AT 02/1500Z AT 02/1200Z CENTER WAS LOCATED NEAR 16.5N 112.2W FORECAST VALID 03/0000Z 17.6N 114.0W MAX WIND 75 KT...GUSTS 90 KT. 64 KT... 20NE 0SE 0SW 20NW. 50 KT... 50NE 30SE 20SW 40NW. 34 KT...120NE 70SE 50SW 80NW. FORECAST VALID 03/1200Z 18.4N 115.5W MAX WIND 85 KT...GUSTS 105 KT. 64 KT... 25NE 20SE 15SW 20NW. 50 KT... 60NE 40SE 30SW 50NW. 34 KT...110NE 80SE 70SW 90NW. FORECAST VALID 04/0000Z 18.9N 116.8W MAX WIND 90 KT...GUSTS 110 KT. 64 KT... 30NE 25SE 15SW 25NW. 50 KT... 60NE 40SE 40SW 50NW. 34 KT...100NE 90SE 80SW 90NW. FORECAST VALID 04/1200Z 19.4N 118.2W MAX WIND 90 KT...GUSTS 110 KT. 64 KT... 30NE 25SE 15SW 25NW. 50 KT... 50NE 40SE 40SW 50NW. 34 KT...100NE 80SE 80SW 90NW. FORECAST VALID 05/1200Z 20.6N 121.8W MAX WIND 70 KT...GUSTS 85 KT. 50 KT... 50NE 40SE 30SW 50NW. 34 KT...100NE 80SE 60SW 80NW. 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 06/1200Z 22.5N 126.0W MAX WIND 55 KT...GUSTS 65 KT. OUTLOOK VALID 07/1200Z 23.5N 130.5W MAX WIND 45 KT...GUSTS 55 KT. REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 16.7N 112.6W NEXT ADVISORY AT 02/2100Z $$ FORECASTER ZELINSKY

No Mesoscale Discussions are in effect as of Mon Sep 2 13:42:02 UTC 2019.

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0751 AM CDT Mon Sep 02 2019 Valid 021300Z - 031200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS SOUTHEAST ND TO WEST-CENTRAL WI... ...SUMMARY... Severe thunderstorms are possible this afternoon through early morning Tuesday across parts of the Upper Midwest, with the most likely corridor from southeast North Dakota to west-central Wisconsin. Large hail and damaging winds should be the primary hazards, with the risk for tornadoes much more uncertain. ...Upper Midwest... Details regarding the low-level thermodynamic profile and surface pattern suggest the forecast is complex and low confidence. While previous forecast may have been too aggressive for the time frame, have opted to refrain from a categorical downgrade and instead drive the Enhanced Slight with hail northwest and wind southeast. An amplifying shortwave trough over Alberta should dig into ND and northern MN overnight, yielding increasing mid-level height falls late in the period. A band of 700-mb warm advection will support elevated convection spreading from the northeast MT/northwest ND border area across ND through this afternoon. Thin elevated buoyancy but pronounced mid to upper-level speed shear will support potential for a long-track cell or two to produce severe hail towards the Red River Valley. By late afternoon/early evening, substantial differences exist in guidance with the degree of diurnal destabilization. The 06Z NAM has effectively negligible surface-based buoyancy across most of the severe outlook area through 00Z with its warm front holding near the MT/ND border arcing across southeast SD into the Lower MO Valley. It suggests stratus will remain pervasive to the north/east beneath an increasingly stout elevated mixed layer. Given that an anticyclone over southeast MB is expected to only slowly decay as it slides toward Lake Superior, this scenario is at least plausible. While guidance such as the RAP indicates much more aggressive surface-based destabilization northward into ND, with a more volatile severe setup along/ahead of the impinging cold front during the evening. The most probable convective scenario is for elevated convection to spread southeast and increase in coverage to a broader MCS from the Red River to Upper MS Valleys tonight. The low-level thermodynamic profile will be critical to the potential severe wind and tornado hazards. Consensus of guidance suggests lapse rates from the surface to 850 mb may remain poor until about 09Z. Still, ample MUCAPE and approach of fast 700-500 mb westerlies suggest an organized but largely elevated MCS should develop across parts of MN to WI. This would likely offer a risk for damaging winds overnight, with a conditional threat for QLCS tornadoes if near 70 surface dew points can be realized ahead of the line. ...Southern New England through northern VA... A convective band is ongoing from eastern PA to western New England in association with a low-amplitude shortwave impulse. This impulse will quickly eject into the Canadian Maritimes by evening, resulting in stronger 850-700 mb winds becoming confined across New England this afternoon. A pronounced gradient in surface dew points is currently prevalent from the mid to upper 50s in southern New England to the low 70s in the Chesapeake/Potomac region. This suggests that surface-based buoyancy should be weak where low-level hodographs can remain modestly enlarged, yielding an isolated damaging wind/brief tornado threat. Farther southwest, isolated to scattered thunderstorms may develop as a weaker upstream impulse shifts east from Lower MI and interacts with a lee surface trough. Adequate deep-layer shear will exist for isolated strong gusts and marginally severe hail. ...East-central FL Coast... Hurricane Dorian is forecast to drift northwest through the period, remaining far enough offshore to limit the overall tornado threat. However, some veering of the wind profile with height is expected to persist where north-northwest surface winds are sustained along a portion of the FL Atlantic Coast. This will support modestly enlarged low-level hodographs. Any cells that can develop in outer rainbands this afternoon into tonight might pose a risk for a brief tornado. ..Grams/Leitman.. 09/02/2019 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0751 AM CDT Mon Sep 02 2019 Valid 021300Z - 031200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS SOUTHEAST ND TO WEST-CENTRAL WI... ...SUMMARY... Severe thunderstorms are possible this afternoon through early morning Tuesday across parts of the Upper Midwest, with the most likely corridor from southeast North Dakota to west-central Wisconsin. Large hail and damaging winds should be the primary hazards, with the risk for tornadoes much more uncertain. ...Upper Midwest... Details regarding the low-level thermodynamic profile and surface pattern suggest the forecast is complex and low confidence. While previous forecast may have been too aggressive for the time frame, have opted to refrain from a categorical downgrade and instead drive the Enhanced Slight with hail northwest and wind southeast. An amplifying shortwave trough over Alberta should dig into ND and northern MN overnight, yielding increasing mid-level height falls late in the period. A band of 700-mb warm advection will support elevated convection spreading from the northeast MT/northwest ND border area across ND through this afternoon. Thin elevated buoyancy but pronounced mid to upper-level speed shear will support potential for a long-track cell or two to produce severe hail towards the Red River Valley. By late afternoon/early evening, substantial differences exist in guidance with the degree of diurnal destabilization. The 06Z NAM has effectively negligible surface-based buoyancy across most of the severe outlook area through 00Z with its warm front holding near the MT/ND border arcing across southeast SD into the Lower MO Valley. It suggests stratus will remain pervasive to the north/east beneath an increasingly stout elevated mixed layer. Given that an anticyclone over southeast MB is expected to only slowly decay as it slides toward Lake Superior, this scenario is at least plausible. While guidance such as the RAP indicates much more aggressive surface-based destabilization northward into ND, with a more volatile severe setup along/ahead of the impinging cold front during the evening. The most probable convective scenario is for elevated convection to spread southeast and increase in coverage to a broader MCS from the Red River to Upper MS Valleys tonight. The low-level thermodynamic profile will be critical to the potential severe wind and tornado hazards. Consensus of guidance suggests lapse rates from the surface to 850 mb may remain poor until about 09Z. Still, ample MUCAPE and approach of fast 700-500 mb westerlies suggest an organized but largely elevated MCS should develop across parts of MN to WI. This would likely offer a risk for damaging winds overnight, with a conditional threat for QLCS tornadoes if near 70 surface dew points can be realized ahead of the line. ...Southern New England through northern VA... A convective band is ongoing from eastern PA to western New England in association with a low-amplitude shortwave impulse. This impulse will quickly eject into the Canadian Maritimes by evening, resulting in stronger 850-700 mb winds becoming confined across New England this afternoon. A pronounced gradient in surface dew points is currently prevalent from the mid to upper 50s in southern New England to the low 70s in the Chesapeake/Potomac region. This suggests that surface-based buoyancy should be weak where low-level hodographs can remain modestly enlarged, yielding an isolated damaging wind/brief tornado threat. Farther southwest, isolated to scattered thunderstorms may develop as a weaker upstream impulse shifts east from Lower MI and interacts with a lee surface trough. Adequate deep-layer shear will exist for isolated strong gusts and marginally severe hail. ...East-central FL Coast... Hurricane Dorian is forecast to drift northwest through the period, remaining far enough offshore to limit the overall tornado threat. However, some veering of the wind profile with height is expected to persist where north-northwest surface winds are sustained along a portion of the FL Atlantic Coast. This will support modestly enlarged low-level hodographs. Any cells that can develop in outer rainbands this afternoon into tonight might pose a risk for a brief tornado. ..Grams/Leitman.. 09/02/2019 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0751 AM CDT Mon Sep 02 2019 Valid 021300Z - 031200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS SOUTHEAST ND TO WEST-CENTRAL WI... ...SUMMARY... Severe thunderstorms are possible this afternoon through early morning Tuesday across parts of the Upper Midwest, with the most likely corridor from southeast North Dakota to west-central Wisconsin. Large hail and damaging winds should be the primary hazards, with the risk for tornadoes much more uncertain. ...Upper Midwest... Details regarding the low-level thermodynamic profile and surface pattern suggest the forecast is complex and low confidence. While previous forecast may have been too aggressive for the time frame, have opted to refrain from a categorical downgrade and instead drive the Enhanced Slight with hail northwest and wind southeast. An amplifying shortwave trough over Alberta should dig into ND and northern MN overnight, yielding increasing mid-level height falls late in the period. A band of 700-mb warm advection will support elevated convection spreading from the northeast MT/northwest ND border area across ND through this afternoon. Thin elevated buoyancy but pronounced mid to upper-level speed shear will support potential for a long-track cell or two to produce severe hail towards the Red River Valley. By late afternoon/early evening, substantial differences exist in guidance with the degree of diurnal destabilization. The 06Z NAM has effectively negligible surface-based buoyancy across most of the severe outlook area through 00Z with its warm front holding near the MT/ND border arcing across southeast SD into the Lower MO Valley. It suggests stratus will remain pervasive to the north/east beneath an increasingly stout elevated mixed layer. Given that an anticyclone over southeast MB is expected to only slowly decay as it slides toward Lake Superior, this scenario is at least plausible. While guidance such as the RAP indicates much more aggressive surface-based destabilization northward into ND, with a more volatile severe setup along/ahead of the impinging cold front during the evening. The most probable convective scenario is for elevated convection to spread southeast and increase in coverage to a broader MCS from the Red River to Upper MS Valleys tonight. The low-level thermodynamic profile will be critical to the potential severe wind and tornado hazards. Consensus of guidance suggests lapse rates from the surface to 850 mb may remain poor until about 09Z. Still, ample MUCAPE and approach of fast 700-500 mb westerlies suggest an organized but largely elevated MCS should develop across parts of MN to WI. This would likely offer a risk for damaging winds overnight, with a conditional threat for QLCS tornadoes if near 70 surface dew points can be realized ahead of the line. ...Southern New England through northern VA... A convective band is ongoing from eastern PA to western New England in association with a low-amplitude shortwave impulse. This impulse will quickly eject into the Canadian Maritimes by evening, resulting in stronger 850-700 mb winds becoming confined across New England this afternoon. A pronounced gradient in surface dew points is currently prevalent from the mid to upper 50s in southern New England to the low 70s in the Chesapeake/Potomac region. This suggests that surface-based buoyancy should be weak where low-level hodographs can remain modestly enlarged, yielding an isolated damaging wind/brief tornado threat. Farther southwest, isolated to scattered thunderstorms may develop as a weaker upstream impulse shifts east from Lower MI and interacts with a lee surface trough. Adequate deep-layer shear will exist for isolated strong gusts and marginally severe hail. ...East-central FL Coast... Hurricane Dorian is forecast to drift northwest through the period, remaining far enough offshore to limit the overall tornado threat. However, some veering of the wind profile with height is expected to persist where north-northwest surface winds are sustained along a portion of the FL Atlantic Coast. This will support modestly enlarged low-level hodographs. Any cells that can develop in outer rainbands this afternoon into tonight might pose a risk for a brief tornado. ..Grams/Leitman.. 09/02/2019 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0751 AM CDT Mon Sep 02 2019 Valid 021300Z - 031200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS SOUTHEAST ND TO WEST-CENTRAL WI... ...SUMMARY... Severe thunderstorms are possible this afternoon through early morning Tuesday across parts of the Upper Midwest, with the most likely corridor from southeast North Dakota to west-central Wisconsin. Large hail and damaging winds should be the primary hazards, with the risk for tornadoes much more uncertain. ...Upper Midwest... Details regarding the low-level thermodynamic profile and surface pattern suggest the forecast is complex and low confidence. While previous forecast may have been too aggressive for the time frame, have opted to refrain from a categorical downgrade and instead drive the Enhanced Slight with hail northwest and wind southeast. An amplifying shortwave trough over Alberta should dig into ND and northern MN overnight, yielding increasing mid-level height falls late in the period. A band of 700-mb warm advection will support elevated convection spreading from the northeast MT/northwest ND border area across ND through this afternoon. Thin elevated buoyancy but pronounced mid to upper-level speed shear will support potential for a long-track cell or two to produce severe hail towards the Red River Valley. By late afternoon/early evening, substantial differences exist in guidance with the degree of diurnal destabilization. The 06Z NAM has effectively negligible surface-based buoyancy across most of the severe outlook area through 00Z with its warm front holding near the MT/ND border arcing across southeast SD into the Lower MO Valley. It suggests stratus will remain pervasive to the north/east beneath an increasingly stout elevated mixed layer. Given that an anticyclone over southeast MB is expected to only slowly decay as it slides toward Lake Superior, this scenario is at least plausible. While guidance such as the RAP indicates much more aggressive surface-based destabilization northward into ND, with a more volatile severe setup along/ahead of the impinging cold front during the evening. The most probable convective scenario is for elevated convection to spread southeast and increase in coverage to a broader MCS from the Red River to Upper MS Valleys tonight. The low-level thermodynamic profile will be critical to the potential severe wind and tornado hazards. Consensus of guidance suggests lapse rates from the surface to 850 mb may remain poor until about 09Z. Still, ample MUCAPE and approach of fast 700-500 mb westerlies suggest an organized but largely elevated MCS should develop across parts of MN to WI. This would likely offer a risk for damaging winds overnight, with a conditional threat for QLCS tornadoes if near 70 surface dew points can be realized ahead of the line. ...Southern New England through northern VA... A convective band is ongoing from eastern PA to western New England in association with a low-amplitude shortwave impulse. This impulse will quickly eject into the Canadian Maritimes by evening, resulting in stronger 850-700 mb winds becoming confined across New England this afternoon. A pronounced gradient in surface dew points is currently prevalent from the mid to upper 50s in southern New England to the low 70s in the Chesapeake/Potomac region. This suggests that surface-based buoyancy should be weak where low-level hodographs can remain modestly enlarged, yielding an isolated damaging wind/brief tornado threat. Farther southwest, isolated to scattered thunderstorms may develop as a weaker upstream impulse shifts east from Lower MI and interacts with a lee surface trough. Adequate deep-layer shear will exist for isolated strong gusts and marginally severe hail. ...East-central FL Coast... Hurricane Dorian is forecast to drift northwest through the period, remaining far enough offshore to limit the overall tornado threat. However, some veering of the wind profile with height is expected to persist where north-northwest surface winds are sustained along a portion of the FL Atlantic Coast. This will support modestly enlarged low-level hodographs. Any cells that can develop in outer rainbands this afternoon into tonight might pose a risk for a brief tornado. ..Grams/Leitman.. 09/02/2019 Read more

000
ABPZ20 KNHC 021123
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
500 AM PDT Mon Sep 2 2019

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

The National Hurricane Center is issuing advisories on Tropical
Storm Juliette, located several hundred miles south-southwest of the
southern tip of the Baja California peninsula.

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

$$
Forecaster Blake

5-Day Uncertainty Track last updated Mon, 02 Sep 2019 08:41:50 GMT


Wind Speed Probabilities last updated Mon, 02 Sep 2019 09:31:49 GMT

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0338 AM CDT Mon Sep 02 2019 Valid 051200Z - 101200Z ...DISCUSSION... Organized severe potential during the extended period will likely concentrate on Thursday (day 4) in association with Hurricane Dorian near the Carolina coast. Thereafter, medium range models show a mid-level ridge generally over the central U.S. with relatively marginal low-level moisture. A mid-level trough will probably move into parts of the West this weekend but model variability is still large. Regardless, potential for organized severe appears limited after Thursday through next weekend. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0338 AM CDT Mon Sep 02 2019 Valid 051200Z - 101200Z ...DISCUSSION... Organized severe potential during the extended period will likely concentrate on Thursday (day 4) in association with Hurricane Dorian near the Carolina coast. Thereafter, medium range models show a mid-level ridge generally over the central U.S. with relatively marginal low-level moisture. A mid-level trough will probably move into parts of the West this weekend but model variability is still large. Regardless, potential for organized severe appears limited after Thursday through next weekend. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0338 AM CDT Mon Sep 02 2019 Valid 051200Z - 101200Z ...DISCUSSION... Organized severe potential during the extended period will likely concentrate on Thursday (day 4) in association with Hurricane Dorian near the Carolina coast. Thereafter, medium range models show a mid-level ridge generally over the central U.S. with relatively marginal low-level moisture. A mid-level trough will probably move into parts of the West this weekend but model variability is still large. Regardless, potential for organized severe appears limited after Thursday through next weekend. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0338 AM CDT Mon Sep 02 2019 Valid 051200Z - 101200Z ...DISCUSSION... Organized severe potential during the extended period will likely concentrate on Thursday (day 4) in association with Hurricane Dorian near the Carolina coast. Thereafter, medium range models show a mid-level ridge generally over the central U.S. with relatively marginal low-level moisture. A mid-level trough will probably move into parts of the West this weekend but model variability is still large. Regardless, potential for organized severe appears limited after Thursday through next weekend. Read more

Issued at 300 AM MDT Mon Sep 02 2019 000 WTPZ41 KNHC 020840 TCDEP1 Tropical Storm Juliette Discussion Number 5 NWS National Hurricane Center Miami FL EP112019 300 AM MDT Mon Sep 02 2019 After struggling to strengthen during the previous 12-h period due to the entrainment of mid-level dry air, a strong burst of deep convection, accompanied by frequent lightning and cloud tops near -90C, has developed near the well-defined low-level circulation center. A nearly circular CDO feature has also formed over the center, and the upper-level outflow has improved and expanded in all quadrants. During the past few hours, SSMI/S and AMSU microwave satellite data indicate that a primitive mid-level eye feature had formed, and recent satellite intensity estimates from TAFB and UW-CIMSS SATCON were T3.5/55 kt and 57 kt, respectively. Based on these data, the initial intensity has been increased to 55 kt. The initial motion is estimate is 300/12 kt. There is no significant change to the previous forecast track or rationale. A deep-layer ridge anchored to the north of Juliette is expected to change little, driving Juliette on a general west-northwestward track throughout the 5-day period. As a result, the new NHC track forecast is very similar to the previous advisory track, and lies down the middle of the tightly clustered model guidance. Now that a nearly complete mid-level eye feature has formed, rapid intensification is expected to occur during the next 24 hours due to Juliette being embedded within very favorable environmental conditions consisting of low vertical wind shear near 5 kt, an unhindered outflow pattern, and a moist mid-level environment, along with traversing warm sea-surface temperatures (SST) of 28-29 deg C. Thereafter, a slower rate of strengthening is expected through 36-48 hours due to the cyclone moving over marginal SSTs. Steady weakening is forecast on days 3-5 when Juliette will be moving over sub-26C SSTs despite low shear conditions. The new official intensity forecast is a little above all of the available intensity guidance, and shows the same peak intensity as the previous advisory, except that the time of occurrence has been moved forward by 24 hours. FORECAST POSITIONS AND MAX WINDS INIT 02/0900Z 16.2N 111.8W 55 KT 65 MPH 12H 02/1800Z 17.0N 113.2W 70 KT 80 MPH 24H 03/0600Z 17.9N 114.9W 85 KT 100 MPH 36H 03/1800Z 18.5N 116.4W 90 KT 105 MPH 48H 04/0600Z 19.0N 117.7W 90 KT 105 MPH 72H 05/0600Z 20.0N 121.3W 75 KT 85 MPH 96H 06/0600Z 21.5N 125.2W 60 KT 70 MPH 120H 07/0600Z 23.0N 129.5W 45 KT 50 MPH $$ Forecaster Stewart

Issued at 0900 UTC MON SEP 02 2019 000 FOPZ11 KNHC 020839 PWSEP1 TROPICAL STORM JULIETTE WIND SPEED PROBABILITIES NUMBER 5 NWS NATIONAL HURRICANE CENTER MIAMI FL EP112019 0900 UTC MON SEP 02 2019 AT 0900Z THE CENTER OF TROPICAL STORM JULIETTE WAS LOCATED NEAR LATITUDE 16.2 NORTH...LONGITUDE 111.8 WEST WITH MAXIMUM SUSTAINED WINDS NEAR 55 KTS...65 MPH...100 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 MON 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 MON 18Z MON 06Z TUE 18Z TUE 06Z WED 06Z THU 06Z FRI PERIODS TO TO TO TO TO TO TO 18Z MON 06Z TUE 18Z TUE 06Z WED 06Z THU 06Z FRI 06Z SAT FORECAST HOUR (12) (24) (36) (48) (72) (96) (120) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - LOCATION KT 15N 110W 34 99 X(99) X(99) X(99) X(99) X(99) X(99) 20N 110W 34 4 2( 6) X( 6) X( 6) X( 6) X( 6) X( 6) ISLA SOCORRO 34 19 4(23) 2(25) X(25) X(25) X(25) X(25) ISLA CLARION 34 31 59(90) 5(95) X(95) X(95) X(95) X(95) ISLA CLARION 50 1 70(71) 9(80) 1(81) X(81) X(81) X(81) ISLA CLARION 64 X 39(39) 12(51) X(51) X(51) X(51) X(51) 15N 115W 34 5 6(11) 4(15) 2(17) X(17) X(17) X(17) 20N 115W 34 5 28(33) 20(53) 3(56) 2(58) X(58) X(58) 20N 115W 50 X 3( 3) 8(11) 1(12) X(12) X(12) X(12) 20N 115W 64 X 1( 1) 1( 2) X( 2) X( 2) X( 2) X( 2) 15N 120W 34 X X( X) 2( 2) 2( 4) 4( 8) 1( 9) X( 9) 20N 120W 34 X 1( 1) 5( 6) 16(22) 58(80) 3(83) 1(84) 20N 120W 50 X X( X) X( X) 3( 3) 47(50) 2(52) X(52) 20N 120W 64 X X( X) X( X) 1( 1) 28(29) 1(30) X(30) 25N 120W 34 X X( X) X( X) X( X) 3( 3) 2( 5) X( 5) 20N 125W 34 X X( X) X( X) X( X) 7( 7) 34(41) 5(46) 20N 125W 50 X X( X) X( X) X( X) 1( 1) 13(14) 3(17) 20N 125W 64 X X( X) X( X) X( X) X( X) 5( 5) 1( 6) 25N 125W 34 X X( X) X( X) X( X) X( X) 9( 9) 4(13) 20N 130W 34 X X( X) X( X) X( X) X( X) 3( 3) 9(12) 25N 130W 34 X X( X) X( X) X( X) X( X) 1( 1) 11(12) $$ FORECASTER STEWART

Issued at 0900 UTC MON SEP 02 2019 000 WTPZ21 KNHC 020839 TCMEP1 TROPICAL STORM JULIETTE FORECAST/ADVISORY NUMBER 5 NWS NATIONAL HURRICANE CENTER MIAMI FL EP112019 0900 UTC MON SEP 02 2019 THERE ARE NO COASTAL WATCHES OR WARNINGS IN EFFECT. TROPICAL STORM CENTER LOCATED NEAR 16.2N 111.8W AT 02/0900Z POSITION ACCURATE WITHIN 25 NM PRESENT MOVEMENT TOWARD THE NORTHWEST OR 300 DEGREES AT 12 KT ESTIMATED MINIMUM CENTRAL PRESSURE 997 MB MAX SUSTAINED WINDS 55 KT WITH GUSTS TO 65 KT. 50 KT....... 60NE 0SE 0SW 50NW. 34 KT.......130NE 130SE 0SW 100NW. 12 FT SEAS..150NE 150SE 45SW 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 16.2N 111.8W AT 02/0900Z AT 02/0600Z CENTER WAS LOCATED NEAR 15.9N 111.3W FORECAST VALID 02/1800Z 17.0N 113.2W MAX WIND 70 KT...GUSTS 85 KT. 64 KT... 15NE 0SE 0SW 15NW. 50 KT... 60NE 30SE 0SW 50NW. 34 KT...130NE 130SE 40SW 100NW. FORECAST VALID 03/0600Z 17.9N 114.9W MAX WIND 85 KT...GUSTS 105 KT. 64 KT... 25NE 20SE 0SW 20NW. 50 KT... 60NE 40SE 30SW 50NW. 34 KT...130NE 130SE 60SW 110NW. FORECAST VALID 03/1800Z 18.5N 116.4W MAX WIND 90 KT...GUSTS 110 KT. 64 KT... 25NE 20SE 15SW 20NW. 50 KT... 60NE 40SE 30SW 50NW. 34 KT...130NE 130SE 60SW 110NW. FORECAST VALID 04/0600Z 19.0N 117.7W MAX WIND 90 KT...GUSTS 110 KT. 64 KT... 25NE 20SE 15SW 20NW. 50 KT... 60NE 40SE 30SW 50NW. 34 KT...130NE 130SE 60SW 110NW. FORECAST VALID 05/0600Z 20.0N 121.3W MAX WIND 75 KT...GUSTS 90 KT. 50 KT... 60NE 40SE 30SW 50NW. 34 KT...130NE 130SE 60SW 110NW. 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 06/0600Z 21.5N 125.2W MAX WIND 60 KT...GUSTS 75 KT. OUTLOOK VALID 07/0600Z 23.0N 129.5W MAX WIND 45 KT...GUSTS 55 KT. REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 16.2N 111.8W NEXT ADVISORY AT 02/1500Z $$ FORECASTER STEWART

Issued at 300 AM MDT Mon Sep 02 2019 000 WTPZ31 KNHC 020839 TCPEP1 BULLETIN Tropical Storm Juliette Advisory Number 5 NWS National Hurricane Center Miami FL EP112019 300 AM MDT Mon Sep 02 2019 ...JULIETTE STRENGTHENS... ...EXPECTED TO BECOME A HURRICANE LATER TODAY... SUMMARY OF 300 AM MDT...0900 UTC...INFORMATION ---------------------------------------------- LOCATION...16.2N 111.8W ABOUT 480 MI...770 KM SSW OF THE SOUTHERN TIP OF BAJA CALIFORNIA MAXIMUM SUSTAINED WINDS...65 MPH...100 KM/H PRESENT MOVEMENT...WNW OR 300 DEGREES AT 14 MPH...22 KM/H MINIMUM CENTRAL PRESSURE...997 MB...29.44 INCHES WATCHES AND WARNINGS -------------------- There are no coastal watches or warnings in effect. DISCUSSION AND OUTLOOK ---------------------- At 300 AM MDT (0900 UTC), the center of Tropical Storm Juliette was located near latitude 16.2 North, longitude 111.8 West. Juliette is moving toward the west-northwest near 14 mph (22 km/h). A west-northwestward motion with some decrease in forward speed is forecast through Wednesday. Maximum sustained winds have increased to near 65 mph (100 km/h) with higher gusts. Strengthening is forecast during the next 48 hours, and Juliette is expected to become a hurricane later today. Tropical-storm-force winds extend outward up to 150 miles (240 km) from the center. The estimated minimum central pressure is 997 mb (29.44 inches). HAZARDS AFFECTING LAND ---------------------- None. NEXT ADVISORY ------------- Next complete advisory at 900 AM MDT. $$ Forecaster Stewart