Tropical Storm DORA
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TROPICAL STORM DORA DISCUSSION NUMBER 6
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2 AM PDT TUE JUL 05 2005
THE AERIAL COVERAGE OF CONVECTION ASSOCIATED WITH DORA HAS DECREASED
THIS MORNING. HOWEVER...THERE REMAINS A PERSISTENT CENTRAL
CONVECTIVE FEATURE WITH OCCASIONAL CLOUD TOPS TO -80C JUST OFF THE
COAST OF MEXICO. SATELLITE INTENSITY ESTIMATES REMAIN 35 KT FROM
TAFB...SAB...AND AFWA...SO THAT IS THE INITIAL INTENSITY.
THE INITIAL MOTION IS NOW 295/12...FASTER AND SLIGHTLY MORE TO THE
LEFT THAN 6 HR AGO. DORA IS ON THE SOUTH SIDE OF A LOW/MID LEVEL
RIDGE THAT COVERS NORTHERN MEXICO AND THE SOUTHWESTERN UNITED
STATES...AND LARGE-SCALE MODELS FORECAST THIS FEATURE TO PERSIST
FOR AT LEAST 96 HR. THIS SHOULD STEER DORA GENERALLY
WEST-NORTHWESTWARD FOR 24-48 HR...AND THEN WESTWARD FROM 48-96 HR.
THERE IS SOME DIVERGENCE IN THE NHC TRACK GUIDANCE...AS THE
DYNAMICAL MODELS ALL TAKE DORA NORTHWESTWARD FROM 48-72 HR BEFORE
DISSIPATING THE SYSTEM....WHILE THE NHC91 AND THE VARIOUS BAM
MODELS FORECAST A MORE CLIMATOLOGICAL WEST-NORTHWESTWARD AND THEN
WESTWARD MOTION. THE OFFICIAL FORECAST WILL FOLLOW THE NHC91/BAM
SCENARIO AND IS SIMILAR TO...BUT FASTER THAN...THE PREVIOUS
FORECAST.
DORA IS IN AN ENVIRONMENT OF MODERATE EASTERLY SHEAR...WHICH SHOULD
CONTINUE FOR THE NEXT 72-96 HR. PROXIMITY TO THE MOUNTAINS OF
SOUTHWESTERN MEXICO HAS LIKELY BEEN SLOWING DEVELOPMENT...BUT DORA
SHOULD MOVE FARTHER AWAY FROM THOSE MOUNTAINS AFTER 12-24 HR. THIS
COULD ALLOW SOME STRENGTHENING BEFORE THE STORM REACHES COOLER
WATER IN 36-48 HR. AS NOTED...THE DYNAMICAL MODELS ALL WEAKEN
DORA...INCLUDING THE GFDL THAT CALLS FOR DISSIPATION AFTER 42 HR.
THE SHIPS MODEL STRENGTHENS THE STORM TO 50 KT IN 36 HR...WITH
WEAKENING THEREAFTER. THE INTENSITY FORECAST IS IN BEST AGREEMENT
WITH SHIPS...BUT CALLS FOR A 45 KT PEAK INTENSITY IN 36 HR.
FORECASTER BEVEN
FORECAST POSITIONS AND MAX WINDS
INITIAL 05/0900Z 17.9N 103.3W 35 KT
12HR VT 05/1800Z 18.5N 104.6W 35 KT
24HR VT 06/0600Z 19.2N 106.2W 40 KT
36HR VT 06/1800Z 19.7N 107.8W 45 KT
48HR VT 07/0600Z 20.1N 109.4W 45 KT
72HR VT 08/0600Z 20.5N 113.0W 35 KT
96HR VT 09/0600Z 20.5N 117.0W 25 KT...DISSIPATING
120HR VT 10/0600Z 20.5N 121.0W 20 KT...REMNANT LOW
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