000
WTPZ41 KNHC 080842
TCDEP1
 
TROPICAL STORM ADRIAN DISCUSSION NUMBER   4
NWS NATIONAL HURRICANE CENTER MIAMI FL       EP012011
200 AM PDT WED JUN 08 2011
 
SATELLITE IMAGERY SHOWS THAT ADRIAN CONTINUES TO STRENGTHEN THIS
MORNING...WITH INCREASING CENTRAL CONVECTION AND AN OUTER BAND OVER
THE WESTERN SEMICIRCLE.  SATELLITE INTENSITY ESTIMATES ARE 55 KT
FROM SAB AND 45 KT FROM TAFB...SO THE INITIAL INTENSITY IS
INCREASED TO 50 KT.  THE CIRRUS OUTFLOW IS GOOD IN THE WESTERN
SEMICIRCLE AND POOR ELSEWHERE.

THE INITIAL MOTION IS A SOMEWHAT UNCERTAIN 310/4.  ADRIAN IS
CURRENTLY IN A COL REGION NEAR THE SOUTHWESTERN END OF A
MID/UPPER-LEVEL TROUGH OVER THE GULF OF MEXICO.  THE LARGE-SCALE
MODELS SUGGEST THAT A MID-LEVEL RIDGE WILL BUILD NORTH OF ADRIAN
DURING THE NEXT 48 HR.  THIS PATTERN EVOLUTION WOULD ALLOW THE
CYCLONE TO MOVE NORTHWESTWARD TO NORTH-NORTHWESTWARD FOR 24 H OR
SO...FOLLOWED BY A WEST-NORTHWESTWARD MOTION.  WHILE GENERALLY
AGREEING WITH THIS SCENARIO...THERE REMAINS A SIGNIFICANT SPREAD IN
THE GUIDANCE.  THE GFDL...HWRF...NOGAPS...AND FLORIDA STATE
SUPERENSEMBLE ARE ON THE RIGHT SIDE OF THE GUIDANCE ENVELOPE AND
BRING ADRIAN NEAR THE COAST OF MEXICO BEFORE TURNING IT PARALLEL TO
THE COAST.  THE GFS...ECMWF...AND UKMET KEEP THE STORM FARTHER
OFFSHORE.  THE NEW FORECAST TRACK IS SIMILAR TO...BUT A LITTLE
SOUTH OF...THE PREVIOUS FORECAST BASED MAINLY ON THE INITIAL
POSITION...AND LIKE THE PREVIOUS FORECAST IT LIES TO THE LEFT OF
THE MODEL CONSENSUS.  

ADRIAN IS IN A LIGHT VERTICAL SHEAR ENVIRONMENT AND OVER SEA SURFACE
TEMPERATURES OF NEAR 30C...AND THIS IS LIKELY TO REMAIN THE CASE
FOR THE NEXT 24-36 H.  THE RAPID INTENSIFICATION INDEX OF THE SHIPS
MODEL SHOWS AN 80 PERCENT CHANCE OF 30 KT OF STRENGTHENING DURING
THE NEXT 24 H...AND A 77 PERCENT CHANCE OF 40 KT OF STRENGTHENING. 
A NEGATIVE FACTOR CONTINUES TO BE DRY AIR TO THE WEST OF THE
STORM...WHICH THE SHIPS MODEL SUGGEST COULD AFFECT THE SYSTEM AFTER
24 H.  THE NEW INTENSITY FORECAST CALLS FOR RAPID STRENGTHENING FOR
THE FIRST 24 H...FOLLOWED BY A SLOWER STRENGTHENING RATE FROM 24-48
H IN ANTICIPATION OF DRY AIR ENTRAINMENT.  THIS PART OF THE
FORECAST IS AT THE UPPER EDGE OF THE INTENSITY GUIDANCE ENVELOPE. 
AFTER 48 H...DECREASING SEA SURFACE TEMPERATURES SHOULD CAUSE A
GRADUAL WEAKENING.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  08/0900Z 12.0N 100.9W   50 KT  60 MPH
 12H  08/1800Z 12.6N 101.4W   60 KT  70 MPH
 24H  09/0600Z 13.4N 102.0W   75 KT  85 MPH
 36H  09/1800Z 14.1N 103.1W   85 KT 100 MPH
 48H  10/0600Z 14.7N 104.3W   90 KT 105 MPH
 72H  11/0600Z 15.5N 106.5W   90 KT 105 MPH
 96H  12/0600Z 16.5N 108.5W   80 KT  90 MPH
120H  13/0600Z 17.5N 110.5W   60 KT  70 MPH
 
$$
FORECASTER BEVEN