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ZCZC MIATCDAT4 ALL
TTAA00 KNHC DDHHMM
TROPICAL STORM CLAUDETTE DISCUSSION NUMBER 3
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
5 AM EDT WED JUL 09 2003

A reconnaissance plane encountered a small band of flight level winds near 85 knots just northeast of the center at 04z, but more recently could only find 55-knot winds in the same area. The 85-knot observation could be used to upgrade Claudette to a hurricane. However, since the central pressure increased to 1004 millibars and the high winds appear to have been transitory, the official one-minute surface wind speed is estimated at 60 knots.

The Statistical Hurricane Intensity Prediction Scheme model strengthens Claudette to 76 knots in 36 hours followed by weakening over the Yucatan Peninsula after 48 hours. The latest infrared satellite images show the central dense overcast feature distorted, the outer convective band has diminished, and there appears to be a flattening of the west side outflow by southwesterly winds aloft. These features along with the rise in central pressure are signs of inhibiting the strengthening process for the next several hours, but then strengthening may resume. The official forecast is to 70 knots in 36 hours.

The initial motion estimate is 275/22. The storm is embedded in deep easterlies to the south of a deep layer mean ridge. This ridge is forecast to break down over the Gulf of Mexico by day 4, which should result in a gradual slowing of forward speed and more northward component of motion. The guidance is generally in good agreement about a slowing west-northwestward track for 3 days bringing the storm across the Yucatan Peninsula and over the southwest Gulf of Mexico. Guidance diverges some by day 5 with the Global Forecasting System model showing a location over the Bay of Campeche and the Navy Operational Global Atmospheric Prediction System model has the center over the north central Gulf. The official forecast follows a consensus of the guidance in between these extremes.

I have been unable to contact the national meteorological service of Mexico by telephone to coordinate a hurricane watch for the Yucatan Peninsula.

Forecaster Lawrence

Forecast positions and max winds

INITIAL 09/0900Z 15.3N 75.5W 60 KT
12HR VT 09/1800Z 15.7N 78.6W 60 KT
24HR VT 10/0600Z 17.2N 82.5W 65 KT
36HR VT 10/1800Z 18.7N 85.6W 70 KT
48HR VT 11/0600Z 20.0N 88.0W 70 KT
72HR VT 12/0600Z 22.0N 91.0W 35 KT
96HR VT 13/0600Z 23.5N 92.5W 45 KT
120HR VT 14/0600Z 25.0N 93.0W 55 KT

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BULLETIN
TROPICAL STORM CLAUDETTE ADVISORY NUMBER 3
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
5 AM EDT WED JUL 09 2003

...Claudette moving swiftly across central Caribbean Sea...

A tropical storm warning remains in effect for Jamaica and Grand Cayman. A tropical storm watch remains in effect for Little Cayman and Cayman Brac. A hurricane watch likely will be issued for the Mexican Caribbean coast of the Yucatan Peninsula later this morning.

At 5 AM EDT, 0900Z, the center of Tropical Storm Claudette was located near latitude 15.3 degrees north, longitude 75.5 degrees west, or about 200 miles, 325 kilometers, south-southeast of Kingston, Jamaica.

Claudette is moving toward the west near 25 miles per hour, 41 kilometers per hour, and a gradual turn toward the west-northwest is expected during the next 24 hours.

Maximum sustained winds are near 70 miles per hour, 110 kilometers per hour, with higher gusts. There is a potential for strengthening during the next day or so and Claudette could become a hurricane. Tropical storm force winds extend outward up to 160 miles, 260 kilometers from the center.

The estimated minimum central pressure is 1004 millibars, 29.65 inches of mercury.

Above normal tides accompanied by large and dangerous battering waves are expected along the south coast of Jamaica.

Storm total rainfalls of 3 to 6 inches are likely along the path of Claudette.

Repeating the 5 AM EDT position: 15.3 °N, 75.5 °W. Movement toward, west near 25 miles per hour. Maximum sustained winds, 70 mils per hour. Minimum central pressure: 1004 millibars.

For storm information specific to your area, please monitor products issued by your local weather office.

An intermediate advisory will be issued by the national hurricane center at 8 AM EDT followed by the next complete advisory at 11 AM EDT.

Forecaster Lawrence

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000
WTNT44 KNHC 091433
TCDAT4
TROPICAL STORM CLAUDETTE DISCUSSION NUMBER 4
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
11 AM EDT WED JUL 09 2003

Claudette has weakened some this morning. Southwesterly vertical shear has exposed the center intermittently on the edge of the convection, and a reconnaissance aircraft indicates a central pressure of 1004 millibars along with flight-level winds of 59 knots. Based on this, the maximum winds are reduced to 55 knots, and this may be a little generous.

The initial motion is 275/21. There is little change in the synoptic pattern and the forecast philosophy from the previous package. Claudette remains south of a deep layer subtropical ridge, whose western end is forecast to weaken after 36 hours as a deep-layer trough develops over the eastern United States. Claudette will likely be too far south and west to recurve ahead of the trough, so the most likely response of the storm is a slow motion while over the Gulf of Mexico. The track forecast calls for a gradually decelerating west-northwestward motion through 36-48 hours as Claudette approaches the western end of the ridge, followed by a slower northwestward motion over the Gulf of Mexico. This track forecast is along the southern edge of the dynamical models. It should be noted that Beta and Advection Model Shallow and National Hurricane Center 98 are south of the current forecast, but could verify if Claudette weakens further.

Aircraft data shows that the Claudette vortex is rather small, so there is a distinct possibility that if the shear persists the system could weaken to an easterly wave. Assuming that does not happen, large-scale models forecast the upper-level low west of Claudette to weaken after 12-24 hours and the shear to decrease. The low appears stronger on water vapor imagery than on any of the model forecasts for 12Z, so it will likely hang on longer than the models currently forecast. Based on this, the intensity forecast will call for Claudette to change little for the next 24 hours in a marginal-at-best environment, followed by strengthening as the cyclone approaches Yucatan. By the time Claudette reaches the Gulf of Mexico, a large-scale upper-level anticyclone should be in place to provide a favorable environment.

Forecaster Beven

Forecast positions and max winds

INITIAL 09/1500Z 15.5N 77.6W 55 KT
12HR VT 10/0000Z 16.3N 80.5W 55 KT
24HR VT 10/1200Z 17.6N 83.8W 55 KT
36HR VT 11/0000Z 19.1N 86.7W 60 KT
48HR VT 11/1200Z 20.5N 89.0W 40 KT, INLAND
72HR VT 12/1200Z 22.5N 91.5W 45 KT, OVER WATER
96HR VT 13/1200Z 24.0N 93.0W 50 KT
120HR VT 14/1200Z 25.5N 94.0W 60 KT

000
WTNT34 KNHC 091436
TCPAT4
BULLETIN
TROPICAL STORM CLAUDETTE ADVISORY NUMBER 4
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
11 AM EDT WED JUL 09 2003

...Claudette weakens slightly...

At 11 AM EDT, 1500 UTC, the government of Mexico has issued a hurricane watch for the east coast of the Yucatan Peninsula from Chetumal to Cabo Catoche.

A tropical storm warning remains in effect for Jamaica and Grand Cayman. A tropical storm watch remains in effect for Little Cayman and Cayman Brac.

At 11 AM EDT, 1500Z, the center of Tropical Storm Claudette was located near latitude 15.5 degrees north, longitude degrees 77.6 west, or about 175 miles, 280 kilometers, south-southwest of Kingston, Jamaica.

Claudette is moving toward the west near 24 miles per hour, 39 kilometers per hour. A gradual turn toward the west-northwest at a slower forward speed is expected during the next 24 hours.

Reports from an Air Force Reserve hurricane hunter aircraft indicate maximum sustained winds have decreased to near 65 miles per hour, 100 kilometers per hour, with higher gusts. Upper level winds are not currently favorable for development, and little change in strength is forecast during the next 24 hours.

Tropical storm force winds extend outward up to 160 miles, 260 kilometers mainly to the north of the center.

The latest minimum central pressure reported by the hurricane hunter is 1004 millibars, 29.65 inches of mercury.

Above normal tides accompanied by large and dangerous battering waves are expected along the south coast of Jamaica.

Storm total rainfalls of 3 to 6 inches are likely in association with Claudette. Satellite imagery indicates that rain bands should be spreading over Jamaica in the next few hours.

Repeating the 11 AM EDT position: 15.5 °N, 77.6 °W. Movement toward, west near 24 miles per hour. Maximum sustained winds, 65 miles per hour. Minimum central pressure: 1004 millibars.

For storm information specific to your area, please monitor products issued by your local weather office.

An intermediate advisory will be issued by the national hurricane center at 2 PM EDT followed by the next complete advisory at 5 PM EDT.

Forecaster Beven