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TROPICAL DEPRESSION CHANTAL DISCUSSION NUMBER  27
NATIONAL WEATHER SERVICE MIAMI FL
5 AM EDT WED AUG 22 2001
 
CHANTAL REMAINS OVER LAND NEAR THE GULF OF MEXICO COAST OF WESTERN 
YUCATAN.  THE LOW-LEVEL CENTER IS LOCATED ABOUT 40 NM ENE OF CARMEN 
MEXICO...WHILE A MID-LEVEL CIRCULATION THAT TRACKED NORTHWESTWARD 
OUT OF NORTHERN GUATEMALA IS LOCATED OVER CARMEN.  MEANWHILE...DEEP 
CONVECTION HAS REDEVELOPED FARTHER EAST OVER BELIZE AND EASTERN 
YUCATAN.  NEEDLESS TO SAY...CHANTAL REMAINS POORLY ORGANIZED.

A ROUGH ESTIMATE OF THE INITIAL MOTION IS 280/7...BASED MAINLY ON 
EXTRAPOLATION FROM THE PREVIOUS FORECAST TRACK AND NIGHTTIME VISIBLE 
SATELLITE IMAGERY.  A LARGE SPREAD IN THE GUIDANCE AFTER 24 HOURS 
HAS CONTINUED WITH THE 06Z MODEL RUNS.  THE GFDL NOW TAKES CHANTAL 
OVER THE GULF AND THEN NORTHWARD TO NEAR TAMPICO IN 72 HOURS... 
WHILE THE AVN AND UKMET MODELS DRIVE THE CYCLONE WEST INTO THE GULF 
THROUGH 24 HOURS AND THEN TURN CHANTAL SOUTHWARD INTO MEXICO 
AFTERWARDS.  WATER VAPOR IMAGERY INDICATES THE DIGGING MID- AND 
UPPER-LEVEL TROUGH OVER THE WESTERN AND SOUTHERN GULF OF MEXICO HAS 
BOTTOMED OUT NOW.  HOWEVER...THE LOW-LEVEL RIDGING BENEATH THE UPPER 
TROUGH SHOULD STILL BE STRONG ENOUGH TO KEEP CHANTAL ON A GENERAL 
WESTWARD TRACK THROUGH AT LEAST 36 HOURS. THE NORTH TO NORTHEASTERLY 
MID- AND UPPER-LEVEL FLOW SHOULD HELP TO DRIVE THE CYCLONE TO THE 
SOUTHWEST AND INLAND IF CHANTAL RE-INTENSIFIES AND BECOMES A 
VERTICALLY DEEP SYSTEM AGAIN.  THE OFFICAL FORECAST IS BETWEEN THE 
PREVIOUS FORECAST TRACK AND THE AVN-UKMET CONSENSUS TRACK.
 
WATER VAPOR IMAGERY INDICATES THAT THE NORTHERLY DRY AIR INTRUSION 
OVER THE BAY OF CAMPECHE TO THE NORTH AND WEST OF CHANTAL HAS 
STARTED TO PUSH MORE WESTWARD.  THIS MAY ALLOW FOR SOME OF THE 
DEEPER MOISTURE OVER THE YUCATAN AND NW CARIBBEAN SEA TO MOVE 
WESTWARD INTO THE BAY OF CAMPECHE...WHICH WOULD FAVOR THE 
RE-DEVELOPMENT OF DEEP CONVECTION ONCE THE LOW-LEVEL CENTER MOVES 
BACK OVER WATER.  HOWEVER...THE INTENSITY FORECAST IS DEPENDENT ON 
WHERE THE CENTER OF CHANTAL ACTUALLY TRACKS.  IF IT REMAINS CLOSER 
TO LAND...THEN ANY SIGNIFICANT RE-INTENSIFICATION WILL BE UNLIKELY.
 
FORECASTER STEWART
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL     22/0900Z 19.0N  91.2W    25 KTS...INLAND
12HR VT     22/1800Z 19.1N  92.2W    30 KTS
24HR VT     23/0600Z 19.1N  94.0W    35 KTS
36HR VT     23/1800Z 18.7N  95.0W    45 KTS
48HR VT     24/0600Z 17.7N  95.3W    25 KTS...INLAND AND DISSIPATING
72HR VT     25/0600Z...INLAND AND DISSIPATED
 
 
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