30 Aug Weather in Cayman & Tropical Report, 1 TS, 1 dist Atlantic

August 30, 2017

Aug 30 Wednesday 2017

Tropical Report

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
800 AM EDT Wed Aug 30 2017

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

The National Hurricane Center is issuing advisories on Tropical
Storm Harvey, located over southwestern Louisiana.

1. Satellite images indicate that the low pressure area a couple
hundred miles west of the Cabo Verde Islands has become better
organized overnight, and advisories will likely be initiated at 11
AM EDT on a tropical cyclone. The system is forecast to gradually
intensify and move west-northwestward to westward at about 15 mph
over the tropical Atlantic during the next several days.
* Formation chance through 48 hours…high…near 100 percent.
* Formation chance through 5 days…high…near 100 percent.

Forecaster Blake

CENTER OF HARVEY OVER SOUTHWESTERN LOUISIANA… …FLOODING RAINS CONTINUING OVER EXTREME SOUTHEASTERN TEXAS AND SOUTHWESTERN LOUISIANA

Tropical Storm Harvey Discussion Number 40
NWS National Hurricane Center Miami FL AL092017
400 AM CDT Wed Aug 30 2017

Radar, satellite, and surface observations indicate that Harvey’s
center has crossed the coast just west of Cameron, Louisiana, with
most of the associated deep convection located over extreme
southeastern Texas and western Louisiana. Although the rain has
ended in the Houston/Galveston area, the Beaumont/Port Arthur area
was particularly hard hit overnight, with about 12.5 inches reported
at the Jack Brooks Regional Airport since 7 pm CDT. ASCAT data from
late last night indicated that Harvey’s maximum winds were near 40
kt, and the tropical-storm-force wind radii on the eastern side were
a little smaller than previously estimated.

Harvey has turned north-northeastward and is moving a little faster
with an initial motion of 030/6 kt. The cyclone is located on the
northwestern side of a mid-tropospheric high, which should steer it
north-northeastward and the northeastward across the Lower
Mississippi and Tennessee Valleys during the next few days. The
global models indicate that the surface low should dissipate over
the Ohio Valley by day 4, which is now indicated in the NHC
forecast.

Now that Harvey’s center is moving inland, the maximum winds should
gradually decrease during the next few days. Harvey is likely to
weaken to a tropical depression by tonight, and then it could
become a remnant low by day 3. This weakening will not eliminate
the risk of continued heavy rainfall and flooding along Harvey’s
path, although the system’s faster motion will prevent rainfall
totals from being anywhere near what occurred over southeastern
Texas.

Key Messages:

1. Ongoing catastrophic and life-threatening flooding will continue
across southeastern Texas. While the threat of heavy rains has
ended in the Houston/Galveston area, catastrophic and life-
threatening flooding will continue in and around Houston eastward
into southwest Louisiana for the rest of the week. Isolated storm
totals have reached 50 inches over the upper Texas coast, including
the Houston/Galveston metropolitan area. Please heed the advice of
local officials. Do not attempt to travel if you are in a safe
place, and do not drive into flooded roadways. Refer to products
from your local National Weather Service office and the NOAA Weather
Prediction Center for more information on the flooding hazard. A
summary of rainfall totals compiled by the Weather Prediction Center
can be found at: www.wpc.ncep.noaa.gov/discussions/nfdscc1.html

2. The flood threat has spread farther east, and additional rainfall
accumulations of 3 to 6 inches with isolated amounts up to 10 inches
are expected from southwestern Louisiana and the adjacent border of
eastern Texas northeastward into western Kentucky through Friday.
Please heed the advice of local officials and refer to products from
your local National Weather Service office and the NOAA Weather
Prediction Center for more information on the flooding hazard in
these areas.

FORECAST POSITIONS AND MAX WINDS

INIT 30/0900Z 29.8N 93.4W 40 KT 45 MPH…INLAND
12H 30/1800Z 30.4N 92.9W 35 KT 40 MPH…INLAND
24H 31/0600Z 31.7N 92.0W 30 KT 35 MPH…INLAND
36H 31/1800Z 33.3N 90.6W 25 KT 30 MPH…INLAND
48H 01/0600Z 35.0N 88.7W 25 KT 30 MPH…INLAND
72H 02/0600Z 37.5N 84.9W 20 KT 25 MPH…POST-TROP/REMNT LOW
96H 03/0600Z…DISSIPATED

$$
Forecaster Berg

POTENTIAL TROPICAL CYCLONE FOURTEEN-E

Potential Tropical Cyclone Fourteen-E Discussion Number 3
NWS National Hurricane Center Miami FL EP142017
300 AM MDT Wed Aug 30 2017

The large disturbance off the coast of Mexico continues to
gradually become better organized, with some banding features over
the southern portion of the broad circulation. There is still no
indication of a well-defined center, however. The current intensity
estimate remains 25 kt in agreement with a Dvorak estimate from
TAFB. The system/tropical cyclone should be in an environment of
weak to moderate easterly to southeasterly shear over the next few
days so once the circulation consolidates, strengthening is likely
until the system interacts with the southern portion of the Baja
California peninsula. Given the seemingly favorable environment,
the official intensity forecast is somewhat higher than the model
consensus. The cyclone could become a hurricane when it nears Baja
California Sur, although this is not explicitly shown in the NHC
forecast. Later in the forecast period, the cyclone should weaken
while it traverses the cooler water north of Cabo San Lazaro on the
Baja peninsula.

As before, with the lack of a definite center the initial motion is
quite uncertain, with the current estimate at 325/9 kt. For the
next couple of days, the system/tropical cyclone is expected to move
slowly north-northeastward on the eastern end of a broad mid-level
cyclonic gyre. In 3-5 days the motion should bend toward the
northwest and west-northwest due to a mid-level ridge to the north.
The NHC track forecast lies in between the latest GFS and ECMWF
solutions, and is close to the latest simple and corrected dynamical
model consensus predictions. It should be noted that since there is
considerable spread in the model guidance, this official track
forecast has greater-than-usual uncertainty.

It is also important to note that very heavy rain is possible
outside of the watch/warning area in southwestern Mexico. These
rains could cause life-threatening flooding and mudslides. In
addition, wind gusts to tropical storm force are possible along the
coast of Michoacan, Colima and Jalisco states through early
Wednesday due to the system’s large circulation.

FORECAST POSITIONS AND MAX WINDS

INIT 30/0900Z 18.5N 108.8W 25 KT 30 MPH…POTENTIAL TROP CYCLONE
12H 30/1800Z 19.6N 109.3W 30 KT 35 MPH…POTENTIAL TROP CYCLONE
24H 31/0600Z 20.6N 109.8W 35 KT 40 MPH…TROPICAL STORM
36H 31/1800Z 21.6N 110.2W 45 KT 50 MPH
48H 01/0600Z 22.6N 110.5W 55 KT 65 MPH
72H 02/0600Z 24.5N 112.0W 60 KT 70 MPH
96H 03/0600Z 26.5N 114.5W 40 KT 45 MPH
120H 04/0600Z 27.5N 117.0W 25 KT 30 MPH

$$
Forecaster Pasch

Weather In Cayman

Synopsis

Slight to moderate southeast winds and seas are expected for the next 24 hours. An increase in cloudiness from late night and an increase in showers from early morning are also expected, as a tropical wave moves over the Cayman area. Radar images show isolated showers in and around the Cayman area moving towards the west. The National Hurricane Center in Miami Florida is issuing advisories on Tropical Storm Harvey This systems is out of our watch area but further information can be found at www.nhc.noaa.gov. THIS STORM POSES NO THREAT TO THE CAYMAN ISLANDS.

Sunshine just makes the day a little better, but it can also cause sunburns. Check the UV Report below to be prepared

Humidity: 82% (UP from yesterday)

UV: 11.2 EXTREME (DOWN from yesterday)

Temperature: Today’s current temperature – See Weather Forecast Top Right of Website. Yesterday: H 93.1°F L 79.5°F

Wind direction TODAY: E 10-15 mph GC

Wind direction TONIGHT: E 5-10 mph GC

Barometer: 1015:00 mb Steady Rain: Last month: 6.69 in Last 24 hrs 0.00 This month: 4.27 in

12 Rain days in July 14 Rain days in Aug 2 days since rain

2016 Season Total: 20.23 in 2017 Season Total: 23.38 in

*NOTE: Official Government record of rainfall on Grand Cayman (Owen Roberts International Airport) 2016: 27.98 inches or 28.22 inches below the 30 year average rainfall of 56.20 inches. All other readings are from SOUTH SOUND.