5:00 AM AST Thu Aug 27
Posted by cypresstx on 8/27/2015, 5:02 am
...ERIKA A LITTLE STRONGER...CENTER PASSING BETWEEN GUADELOUPE AND ANTIGUA...


000
WTNT35 KNHC 270850
TCPAT5

BULLETIN
TROPICAL STORM ERIKA ADVISORY NUMBER  10
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL052015
500 AM AST THU AUG 27 2015

...ERIKA A LITTLE STRONGER...CENTER PASSING BETWEEN GUADELOUPE AND
ANTIGUA...


SUMMARY OF 500 AM AST...0900 UTC...INFORMATION
----------------------------------------------
LOCATION...16.8N 61.5W
ABOUT 35 MI...55 KM N OF GUADELOUPE
ABOUT 30 MI...45 KM SE OF ANTIGUA
MAXIMUM SUSTAINED WINDS...50 MPH...85 KM/H
PRESENT MOVEMENT...W OR 280 DEGREES AT 16 MPH...26 KM/H
MINIMUM CENTRAL PRESSURE...1003 MB...29.62 INCHES


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

None.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Tropical Storm Warning is in effect for...
* Anguilla
* Saba and St. Eustatius
* St. Maarten
* St. Martin
* St. Barthelemy
* Montserrat
* Antigua and Barbuda
* St. Kitts and Nevisis
* Puerto Rico
* Vieques
* Culebra
* U.S. Virgin Islands
* British Virgin Islands

A Tropical Storm Watch is in effect for...
* Guadeloupe
* North coast of the Dominican Republic from Cabo Engano to Cabo
Frances Viejo
* Southeastern Bahamas
* Turks and Caicos Islands

A Tropical Storm Watch means that tropical storm conditions are
possible within the watch area, generally within 48 hours.

Interests elsewhere in the Dominican Republic should monitor the
progress of Erika.

For storm information specific to your area in the United States,
including possible inland watches and warnings, please monitor
products issued by your local National Weather Service forecast
office. For storm information specific to your area outside the
United States, please monitor products issued by your national
meteorological service.


DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
At 500 AM AST (0900 UTC), the center of Tropical Storm Erika was
located near latitude 16.8 North, longitude 61.5 West. Erika is
moving toward the west near 16 mph (26 km/h). A turn toward the
west-northwest is forecast later today, and this general motion
should continue for the next 48 hours. On the forecast track, the
center of Erika will move near or over portions of the Leeward
Islands this morning, move near the Virgin Islands later today,
move near or north of Puerto Rico tonight, and pass north of the
north coast of the Dominican Republic on Friday.

Maximum sustained winds have increased to near 50 mph (85 km/h) with
higher gusts. Little change in strength is forecast during the next
48 hours.

Tropical storm force winds extend outward up to 105 miles (165 km),
mainly to the north and east of the center.

The latest minimum central pressure based on data from a NOAA
Hurricane Hunter aircraft is 1003 mb (29.62 inches).


HAZARDS AFFECTING LAND
----------------------
WIND: Tropical storm conditions are expected to spread across the
warning area in the Leeward Islands this morning, and reach the
Virgin Islands later today and Puerto Rico tonight. Tropical storm
conditions are possible in the watch area in the Leeward Islands
this morning. Tropical storm conditions could reach portions of the
watch area in the Dominican Republic on Friday and the southeastern
Bahamas, and Turks and the Caicos Islands late Friday and Friday
night.

RAINFALL: Erika is expected to produce total rain accumulations of
3 to 5 inches with maximum amounts of 8 inches across portions of
the Leeward Islands, the Virgin Islands, Puerto Rico, the Dominican
Republic, the Turk and Caicos Islands and the southeast Bahamas
through Saturday.


NEXT ADVISORY
-------------
Next intermediate advisory at 800 AM AST.
Next complete advisory at 1100 AM AST.

$$
Forecaster Brennan


000
WTNT45 KNHC 270856
TCDAT5

TROPICAL STORM ERIKA DISCUSSION NUMBER  10
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL052015
500 AM AST THU AUG 27 2015

Data from a NOAA Hurricane Hunter aircraft indicate that Erika has
strengthened overnight, although it is not clear as to how much. The
central pressure dropped to around 1001 mb around 0540Z, but was
up to 1003 mb on the next fix about an hour later. The highest
850-mb flight-level winds sampled by the aircraft were 48 kt, which
would correspond to an intensity of around 40 kt. However, the
aircraft found SFMR winds of 45 to 55 kt near the center. Based on a
blend of these data, the initial intensity has been conservatively
raised to 45 kt for this advisory. An Air Force Hurricane Hunter
aircraft will be investigating Erika again later this morning.

Aircraft data and satellite imagery show that Erika is still a
sheared tropical cyclone, with the deepest convection found east and
southeast of the center due to about 20 kt of westerly shear. The
models show the environment remaining unfavorable for significant
strengthening in the first 48 hours, with shear associated with an
upper-level trough west of Erika expected to increase to 25 to 30
kt. Given this, most of the intensity guidance shows little change
during the first couple of days and so does the NHC forecast. After
that time, the upper trough weakens and Erika should encounter a
more favorable upper-level pattern and warmer SSTs, which should
support intensification assuming that the cyclone survives the next
48 hours. The HWRF and GFDL are much stronger than the statistical
models this cycle, but the GFS and ECMWF now keep Erika weaker than
they did previously. The NHC forecast has been adjusted upward
slightly late in the period, but is well below the intensity
consensus given the large uncertainty and spread in the guidance.

Aircraft fixes and radar data from Guadeloupe were helpful in
finding the low-level center and determining an initial motion of
280/14. The steering flow from the subtropical ridge to the north
should result in a west-northwestward heading for the next 2 to 3
days. After that time, the spread in the guidance increases as the
cyclone moves between the southwestern edge of the ridge and a
mid/upper-level trough over the southeastern U.S. and Gulf of
Mexico. The models are in poor agreement on the eventual structure
and track of Erika late in the period. The ECMWF is weaker this
cycle and is on the left side of the dynamical model envelope. The
GFS, HWRF, and UKMET are all farther east but have trended west
this cycle. Given the large spread and the continued run-to-run
variability, little change was made to the NHC track forecast. The
new NHC forecast is closest to the latest GFS model prediction at
day 3 and beyond.

One should remember to not focus on the exact forecast track,
especially at the long range where the average NHC track errors
during the past 5 years are about 180 miles at day 4 and 240 miles
at day 5.

FORECAST POSITIONS AND MAX WINDS

INIT  27/0900Z 16.8N  61.5W   45 KT  50 MPH
12H  27/1800Z 17.6N  63.5W   50 KT  60 MPH
24H  28/0600Z 19.0N  66.2W   50 KT  60 MPH
36H  28/1800Z 20.3N  69.0W   50 KT  60 MPH
48H  29/0600Z 21.5N  71.6W   50 KT  60 MPH
72H  30/0600Z 24.0N  76.0W   55 KT  65 MPH
96H  31/0600Z 26.5N  78.5W   65 KT  75 MPH
120H  01/0600Z 29.0N  79.5W   75 KT  85 MPH

$$
Forecaster Brennan


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5:00 AM AST Thu Aug 27 - cypresstx, 8/27/2015, 5:02 am
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