Aug 15 Tuesday 2017

Tropical Report

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
200 AM EDT Tue Aug 15 2017

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

The National Hurricane Center is issuing advisories on Hurricane
Gert, located several hundred miles west of Bermuda.

1. A couple of disorganized areas of disturbed weather are embedded
within an elongated area of low pressure located several hundred
miles west-southwest of the Cabo Verde Islands. Only slow
development is anticipated during the next day or two, but
conditions are forecast to become a little more conducive for
tropical cyclone formation by later in the week while the system
moves westward at about 15 mph over the tropical Atlantic.
* Formation chance through 48 hours…low…20 percent.
* Formation chance through 5 days…medium…60 percent.

2. A tropical wave over western Africa is forecast to emerge into the
far eastern Atlantic Ocean in about two days. Conditions appear
conducive for some development after that time while the wave moves
westward at about 15 mph.
* Formation chance through 48 hours…low…near 0 percent.
* Formation chance through 5 days…low…20 percent.

Forecaster Avila

GERT EXPECTED TO TURN TOWARD THE NORTHEAST LATER TODAY

Hurricane Gert Discussion Number 10
NWS National Hurricane Center Miami FL AL082017
500 AM EDT Tue Aug 15 2017

After a period of intensification several hours ago, recent
satellite images show that the cloud pattern has deteriorated a
little bit. The eye is no longer discernible, and the center is now
located to the west of an area of very deep convection. Dvorak
numbers still support an initial intensity of 65 kt. Gert has an
opportunity to gather some strength in the next day or so after
recurvature. The new NHC forecast is not as aggressive as the
previous one, and it follows very closely the intensity consensus.
Only the HWRF model significantly strengthens the cyclone. After two
days, Gert will be completely embedded within the mid-latitude
westerlies and should become a post-tropical cyclone.

The best estimate of the initial motion is toward the north or 360
degrees at 10 kt. Gert is being steered northward by the flow around
the western edge of the subtropical ridge. The cyclone should then
turn to the northeast with an increase in forward speed later today
as it becomes embedded within the mid-latitude flow. The NHC track
forecast is similar to the previous one, and is in the middle of the
tight guidance envelope.

Swells from Gert are expected to spread northward along the
mid-Atlantic coast of the United States during the next few days.
These swells are likely to produce dangerous surf and rip current
conditions. Please consult products from your local National
Weather Service office.

FORECAST POSITIONS AND MAX WINDS

INIT 15/0900Z 31.8N 72.5W 65 KT 75 MPH
12H 15/1800Z 33.3N 71.5W 70 KT 80 MPH
24H 16/0600Z 35.5N 68.9W 75 KT 85 MPH
36H 16/1800Z 37.8N 64.0W 75 KT 85 MPH
48H 17/0600Z 40.0N 57.0W 70 KT 80 MPH
72H 18/0600Z 46.5N 41.0W 65 KT 75 MPH…POST-TROP/EXTRATROP
96H 19/0600Z 52.0N 36.0W 50 KT 60 MPH…POST-TROP/EXTRATROP
120H 20/0600Z…DISSIPATED

$$
Forecaster Avila

 Tropical Weather Outlook
NWS National Hurricane Center Miami FL
500 AM PDT Tue Aug 15 2017

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

1. An elongated area of disturbed weather is located several hundred
miles southwest of the southern tip of the Baja California
peninsula. Shower and thunderstorm activity remains disorganized,
and development, if any, should be slow to occur while the system
moves slowly westward.
* Formation chance through 48 hours…low…near 0 percent.
* Formation chance through 5 days…low…10 percent.

2. A westward-moving trough of low pressure located several hundred
miles southwest of Acapulco, Mexico, continues to produce limited
showers and thunderstorms. Environmental conditions are not
forecast to support significant development of this system during
the next several days.
* Formation chance through 48 hours…low…near 0 percent.
* Formation chance through 5 days…low…10 percent.

3. A tropical wave near the Gulf of Tehuantepec is producing a
few showers and thunderstorms. Environmental conditions are
expected to be only marginally conducive for development of this
system while it moves west-northwestward to northwestward at 15
to 20 mph.
* Formation chance through 48 hours…low…near 0 percent.
* Formation chance through 5 days…low…10 percent.

Forecaster Zelinsky