000
ABNT20 KNHC 201144
TWOAT

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
800 AM EDT Fri Sep 20 2019

For the North Atlantic...Caribbean Sea and the Gulf of Mexico:

The National Hurricane Center is issuing advisories on Hurricane
Jerry, located a few hundred miles east of the Leeward Islands.

A tropical wave located about 700 miles east of the Windward
Islands continues to produce disorganized showers and thunderstorms.
The wave is expected to move quickly westward at about 20 mph during
the next few days, and some development is possible while it
approaches and moves across the Windward Islands this weekend.
Upper-level winds are forecast to become less conducive for
development once the wave moves over the eastern Caribbean Sea early
next week.
* Formation chance through 48 hours...low...20 percent.
* Formation chance through 5 days...low...30 percent.

A broad area of low pressure located over the central Caribbean Sea
is producing disorganized shower and thunderstorm activity, mainly
to the east and northeast of its center of circulation. This system
is expected to move slowly west-northwestward and significant
development is unlikely due to strong upper-level winds. Regardless
of development, locally heavy rainfall is possible over portions of
the Greater Antilles during the next few days.
* Formation chance through 48 hours...low...10 percent.
* Formation chance through 5 days...low...10 percent.

A tropical wave is forecast to move off the west coast of Africa
this weekend. Environmental conditions are expected to be conducive
for development, and a tropical depression or tropical storm is
likely to form early next week while the wave moves westward across
the eastern tropical Atlantic.
* Formation chance through 48 hours...low...10 percent.
* Formation chance through 5 days...high...70 percent.

$$
Forecaster Zelinsky
more...

...JERRY WEAKER BUT HEAVY RAINS FORECAST OVER THE NORTHERN LEEWARD ISLANDS... As of 11:00 AM AST Fri Sep 20 the center of Jerry was located near 18.8, -60.3 with movement WNW at 17 mph. The minimum central pressure was 990 mb with maximum sustained winds of about 85 mph. more...

Issued at 1100 AM AST Fri Sep 20 2019

000
WTNT35 KNHC 201457
TCPAT5

BULLETIN
Hurricane Jerry Advisory Number  13
NWS National Hurricane Center Miami FL       AL102019
1100 AM AST Fri Sep 20 2019

...JERRY WEAKER BUT HEAVY RAINS FORECAST OVER THE NORTHERN LEEWARD
ISLANDS...


SUMMARY OF 1100 AM AST...1500 UTC...INFORMATION
-----------------------------------------------
LOCATION...18.8N 60.3W
ABOUT 130 MI...205 KM NE OF BARBUDA
ABOUT 190 MI...300 KM ENE OF ANGUILLA
MAXIMUM SUSTAINED WINDS...85 MPH...140 KM/H
PRESENT MOVEMENT...WNW OR 295 DEGREES AT 17 MPH...28 KM/H
MINIMUM CENTRAL PRESSURE...990 MB...29.24 INCHES


WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY:

None.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Tropical Storm Watch is in effect for...
* St. Maarten
* St. Martin
* St. Barthelemy
* Saba and St. Eustatius

A Tropical Storm Watch means that tropical storm conditions are
possible within the watch area, in this case within 12-24 hours.

Interests elsewhere in the northern Leeward Islands should monitor
the progress of Jerry.

For storm information specific to your area, please monitor
products issued by your national meteorological service.


DISCUSSION AND OUTLOOK
----------------------
At 1100 AM AST (1500 UTC), the center of Hurricane Jerry was located
near latitude 18.8 North, longitude 60.3 West. Jerry is moving
toward the west-northwest near 17 mph (28 km/h). On the forecast
track, the center of Jerry will move north of the northern Leeward
Islands later today, pass well north of Puerto Rico on Saturday,
be well east-northeast of the southeastern Bahamas on Sunday and
turn northward on Monday.

Data from the Air Force Reserve and NOAA Hurricane Hunter
aircraft indicate that the maximum sustained winds have decreased to
near 85 mph (140 km/h) with higher gusts. Further weakening is
forecast during the next day or so, with some re-strengthening
possible early next week.

Hurricane-force winds extend outward up to 15 miles (30 km) from the
center and tropical-storm-force winds extend outward up to 80 miles
(130 km).

The estimated minimum central pressure from the plane data is 990 mb
(29.24 inches).


HAZARDS AFFECTING LAND
----------------------
Key messages for Jerry can be found in the Tropical Cyclone
Discussion under AWIPS header MIATCDAT5 and WMO header WTNT45 KNHC
and on the web at www.hurricanes.gov/text/MIATCDAT5.shtml.

RAINFALL: Jerry is expected to produce 1 to 3 inches of rainfall,
with isolated maximum totals of 4 to 6 inches from Barbuda northwest
across St. Maarten, Anguilla, and Anegada. This rainfall may
produce life-threatening flash floods.

Jerry is forecast to produce total rainfall accumulations of 1 to 2
inches with maximum amounts of 3 inches across the Virgin Islands
and Puerto Rico.

WIND: Tropical storm conditions are possible within the watch
areas later today.

SURF: Swells generated by Jerry are affecting portions of the
northern Leeward Islands. These swells are likely to cause
life-threatening surf and rip current conditions.  Please consult
products from your local weather office.


NEXT ADVISORY
-------------
Next intermediate advisory at 200 PM AST.
Next complete advisory at 500 PM AST.

$$
Forecaster Blake

more...

Issued at 1500 UTC FRI SEP 20 2019

000
WTNT25 KNHC 201456
TCMAT5

HURRICANE JERRY FORECAST/ADVISORY NUMBER  13
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL102019
1500 UTC FRI SEP 20 2019

CHANGES IN WATCHES AND WARNINGS WITH THIS ADVISORY...

NONE.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT...

A TROPICAL STORM WATCH IS IN EFFECT FOR...
* ST. MAARTEN
* ST. MARTIN
* ST. BARTHELEMY
* SABA AND ST. EUSTATIUS

A TROPICAL STORM WATCH MEANS THAT TROPICAL STORM CONDITIONS ARE
POSSIBLE WITHIN THE WATCH AREA...IN THIS CASE WITHIN 12-24 HOURS.

INTERESTS ELSEWHERE IN THE NORTHERN LEEWARD ISLANDS SHOULD MONITOR
THE PROGRESS OF JERRY.

HURRICANE CENTER LOCATED NEAR 18.8N  60.3W AT 20/1500Z
POSITION ACCURATE WITHIN  15 NM

PRESENT MOVEMENT TOWARD THE WEST-NORTHWEST OR 295 DEGREES AT  15 KT

ESTIMATED MINIMUM CENTRAL PRESSURE  990 MB
MAX SUSTAINED WINDS  75 KT WITH GUSTS TO  90 KT.
64 KT....... 15NE   0SE   0SW  15NW.
50 KT....... 30NE  20SE  10SW  30NW.
34 KT....... 70NE  40SE  30SW  40NW.
12 FT SEAS..180NE 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 18.8N  60.3W AT 20/1500Z
AT 20/1200Z CENTER WAS LOCATED NEAR 18.5N  59.6W

FORECAST VALID 21/0000Z 19.6N  62.4W
MAX WIND  70 KT...GUSTS  85 KT.
64 KT... 10NE   0SE   0SW  10NW.
50 KT... 30NE  10SE  10SW  20NW.
34 KT... 70NE  40SE  20SW  40NW.

FORECAST VALID 21/1200Z 20.9N  64.7W
MAX WIND  65 KT...GUSTS  80 KT.
64 KT... 10NE   0SE   0SW  10NW.
50 KT... 30NE  10SE  10SW  20NW.
34 KT... 80NE  60SE  20SW  60NW.

FORECAST VALID 22/0000Z 22.3N  66.6W
MAX WIND  60 KT...GUSTS  75 KT.
50 KT... 30NE  20SE   0SW  30NW.
34 KT... 80NE  70SE  30SW  60NW.

FORECAST VALID 22/1200Z 23.6N  68.0W
MAX WIND  60 KT...GUSTS  75 KT.
50 KT... 30NE  20SE   0SW  30NW.
34 KT... 90NE  70SE  30SW  60NW.

FORECAST VALID 23/1200Z 26.5N  69.0W
MAX WIND  65 KT...GUSTS  80 KT.
50 KT... 40NE  30SE  20SW  30NW.
34 KT... 90NE  80SE  40SW  60NW.

EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 150 NM
ON DAY 4 AND 175 NM ON DAY 5...AND FOR INTENSITY NEAR 15 KT EACH DAY

OUTLOOK VALID 24/1200Z 29.0N  67.5W
MAX WIND  65 KT...GUSTS  80 KT.

OUTLOOK VALID 25/1200Z 33.0N  64.0W
MAX WIND  65 KT...GUSTS  80 KT.

REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 18.8N  60.3W

INTERMEDIATE PUBLIC ADVISORY...WTNT35 KNHC/MIATCPAT5...AT 20/1800Z

NEXT ADVISORY AT 20/2100Z

$$
FORECASTER BLAKE

more...

Issued at 1100 AM AST Fri Sep 20 2019

000
WTNT45 KNHC 201457
TCDAT5

Hurricane Jerry Discussion Number  13
NWS National Hurricane Center Miami FL       AL102019
1100 AM AST Fri Sep 20 2019

Data from both NOAA and Air Force Reserve Hurricane Hunter aircraft
indicate that Jerry is weakening quickly, and radar images from NOAA
show no sign of the eyewall reported on the last mission. Maximum
flight-level winds on the mission were about 78 kt, with SFMR values
near 70 kt, and the central pressure has risen about 10 mb
overnight.  These observations also agree with the latest satellite
imagery that shows a less organized cyclone, with the center on the
far northwestern edge of a distorted central dense overcast. A blend
of all these data gives an initial wind speed estimate of 75 kt.

Jerry is moving about the same as before, west-northwestward at
15 kt.  The hurricane should gradually bend to the right and slow
down during the next few days while the cyclone is steered
around the western periphery of a weakening subtropical ridge.  The
guidance is tightly packed on the forecast through Monday, and
little change was made to the previous NHC prediction.  At longer
range, a mid-latitude trough interaction should turn the hurricane
northward and northeastward, but the models are really struggling on
how quickly this occurs. While yesterday much of the guidance had
Jerry accelerating ahead of the trough, today's models have slowed
everything down as the trough looks like it could weaken before
fully recurving the cyclone.  The new track forecast is considerably
slower than the last one beyond 72 hours, about as much as
continuity allows, and later forecasts could slow Jerry down even
more.

Northwesterly shear is forecast to persist near Jerry for the next
day or two, and some weakening is expected.  The intensity forecast
is reduced from the previous one, and could be a bit too high in
the short term given recent trends.  In a few days, the
aforementioned trough interaction is anticipated, but it is next to
impossible to know at this lead time whether the trough will weaken
or strengthen the cyclone, so no forecast change is made.  It is a
little tempting to raise the intensity by the end, given the recent
weaker mid-latitude trough in the models, but there's just too much
track uncertainty to mess with the intensity forecast at this time.


Key Messages:

1. Although the core of Jerry is expected to move north of the
northern Leeward Islands, heavy rainfall and flash floods are
possible there today.


FORECAST POSITIONS AND MAX WINDS

INIT  20/1500Z 18.8N  60.3W   75 KT  85 MPH
 12H  21/0000Z 19.6N  62.4W   70 KT  80 MPH
 24H  21/1200Z 20.9N  64.7W   65 KT  75 MPH
 36H  22/0000Z 22.3N  66.6W   60 KT  70 MPH
 48H  22/1200Z 23.6N  68.0W   60 KT  70 MPH
 72H  23/1200Z 26.5N  69.0W   65 KT  75 MPH
 96H  24/1200Z 29.0N  67.5W   65 KT  75 MPH
120H  25/1200Z 33.0N  64.0W   65 KT  75 MPH

$$
Forecaster Blake

more...