TROPICAL STORM RICHARD DISCUSSION NUMBER   9
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   AL192010
1100 PM EDT FRI OCT 22 2010

RICHARD REMAINS A RAGGED TROPICAL CYCLONE THIS EVENING.  THE
CONVECTION IS IN POORLY DEFINED BANDS EAST OF THE CENTER...AND DATA
FROM A NOAA GULFSTREAM-IV MISSION SHOWS A PRONOUNCED TROUGH
EXTENDING SOUTH FROM THE CENTER.  IN ADDITION...AN AIR FORCE
RESERVE HURRICANE HUNTER AIRCRAFT REPORTED THAT THE STORM HAS A
LARGE AREA OF LIGHT AND VARIABLE WINDS NEAR THE CENTER.  THE AIR
FORCE PLANE REPORTED 925 MB FLIGHT-LEVEL WINDS OF 40 KT AND
SFMR-ESTIMATED SURFACE WINDS OF 35-40 KT.  BASED ON THESE AND
EARLIER BUOY DATA...THE INITIAL INTENSITY REMAINS 40 KT.

THE INITIAL MOTION IS 270/6.  THE INITIAL POSITION IS A LITTLE TO
THE SOUTH OF THE PREVIOUS ADVISORY...AND THUS THE FORECAST TRACK IS
ADJUSTED TO THE SOUTH.  OTHER THAN THAT...THERE IS NO CHANGE IN THE
FORECAST PHILOSOPHY.  A BUILDING LOW/MID-LEVEL RIDGE OVER THE GULF
OF MEXICO IS EXPECTED TO STEER RICHARD WESTWARD TO WEST-
NORTHWESTWARD TOWARD BELIZE AND THE YUCATAN PENINSULA DURING THE
NEXT 72 HR.  AFTER THAT TIME...THE CYCLONE OR ITS REMNANTS ARE
EXPECTED TO TURN NORTHWESTWARD IN THE LOW-LEVEL FLOW NEAR THE
WESTERN END OF THE GULF RIDGE. THE LATTER PART OF THE FORECAST IS
MORE UNCERTAIN DUE TO MODEL DIFFERENCES IN THE STRENGTH OF THE
RIDGE AND HOW STRONG RICHARD MIGHT BE AFTER CROSSING BELIZE AND
MEXICO.  IT SHOULD BE NOTED THAT ANY MOTION SOUTH OF THE FORECAST
TRACK DURING THE FIRST 36 HR COULD BRING THE CENTER NEAR OR OVER
THE COAST OF NORTHERN HONDURAS.

WHILE RICHARD HAS FAIR TO GOOD CIRRUS OUTFLOW IN ALL DIRECTIONS...
THE G-IV DATA SHOW A BAND OF WESTERLY WINDS AT 300 MB BLOWING
UNDER THE CIRRUS INTO THE STORM.  THESE WINDS ARE CREATING ABOUT 15
KT OF WESTERLY SHEAR AND ADVECTING VERY DRY UPPER-LEVEL AIR INTO
THE CORE.  THE LARGE-SCALE MODELS FORECAST THIS SHEAR TO DIMINISH
BY SATURDAY MORNING...AND IF THIS VERIFIES RICHARD IS EXPECTED TO
STRENGTHEN.  THE INTENSITY GUIDANCE IS GENERALLY SHOWING LESS
DEVELOPMENT THAN DURING THE PREVIOUS FORECAST CYCLES...AND THE GFDL
NO LONGER FORECASTS RICHARD TO BECOME A MAJOR HURRICANE.  BASED ON
THIS...THE CURRENT STATE OF THE STORM...AND THE INCREASED CHANCE OF
RICHARD INTERACTING WITH NORTHERN HONDURAS...THE INTENSITY FORECAST
HAS BEEN REVISED DOWNWARD DURING THE FIRST 72 HR.  AFTER EMERGING
INTO THE GULF OF MEXICO...RICHARD IS FORECAST TO ENCOUNTER STRONG
WESTERLY SHEAR WHICH IS EXPECTED TO CAUSE IT TO WEAKEN.

HURRICANE WARNINGS AND WATCHES ARE LIKELY TO BE REQUIRED FOR
PORTIONS ON BELIZE AND THE YUCATAN PENINSULA ON SATURDAY. 
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