Tropical Storm!

Victoria, TX(Zone 9b)

TS Don is on the way ...

http://www.nhc.noaa.gov/#DON

TROPICAL STORM DON DISCUSSION NUMBER 3
NWS NATIONAL HURRICANE CENTER MIAMI FL AL042011
400 AM CDT THU JUL 28 2011

DON HAS NOT CHANGED APPRECIABLY DURING THE PAST SEVERAL HOURS...
MAINTAINING A SMALL AREA OF CONVECTION NEAR THE CENTER. THERE IS
NOT MUCH ORGANIZATION IN THE INFRARED CLOUD PATTERN...WHICH IS
CONFIRMED BY A TRMM MICROWAVE PASS AT 0608Z. ASCAT DATA FROM 0332Z
SUPPORTED AN INITIAL INTENSITY OF AROUND 35 KT...WITH SATELLITE
CLASSIFICATIONS AT OR BELOW THAT VALUE. THE ASCAT DATA CONFIRMED
THE EARLIER AIRCRAFT MEASUREMENTS THAT DON IS A RATHER SMALL
TROPICAL CYCLONE. THE NEXT AIRCRAFT MISSION IS SCHEDULED FOR 1200Z
THIS MORNING.

THE INTENSITY FORECAST IS TRICKY. WHILE THE LARGE-SCALE ENVIRONMENT
DOES NOT APPEAR TO HAVE MUCH SHEAR...THE LOW- AND MID-LEVEL CENTERS
ARE NOT WELL-ALIGNED INITIALLY...WHICH WAS APPARENT ON A 2316Z
SSMIS MICROWAVE IMAGE. THE GFS/ECMWF MODELS HAVE A REASONABLE
REPRESENTATION OF THIS INITIAL STRUCTURE AND KEEP THE CENTERS FROM
VERTICALLY STACKING...POSSIBLY WHY THESE MODELS DO NOT SHOW
MUCH INTENSIFICATION. WHILE THE STATISTICALLY MODELS STILL
FORECAST STEADY STRENGTHENING...THE HWRF/GFDL MODELS FORECAST A
SLOW DECLINE. ANOTHER FACTOR TO CONSIDER IS THAT THE SIZE OF DON
MAKES IT SUSCEPTIBLE TO RAPID CHANGES IN STRENGTH...BOTH UP AND
DOWN...THAT ARE NEARLY IMPOSSIBLE TO FORECAST. GIVEN THE REDUCED
ORGANIZATION...THE NHC INTENSITY FORECAST IS LOWERED SOMEWHAT FROM
THE PREVIOUS FORECAST...BUT IS STILL ON THE UPPER END OF THE
GUIDANCE ENVELOPE NEAR A COMPOSITE OF THE SHIPS/LGEM MODELS.

BEST ESTIMATE OF INITIAL MOTION IS 300/9... WITH OVERNIGHT MICROWAVE
IMAGES SUGGESTING THE SMALL CENTER HAS BEEN MOVING ERRATICALLY. DON
IS MOVING AROUND THE SOUTHERN PERIPHERY OF A RIDGE OVER THE
SOUTHERN UNITED STATES. THIS RIDGE IS FORECAST TO BUILD SLIGHTLY
DURING THE NEXT DAY OR TWO AS A SERIES OF WEAK IMPULSES MOVE AWAY
FROM THE NORTHERN GULF COAST. THIS SYNOPTIC PATTERN SHOULD STEER
THE CYCLONE GENERALLY TO THE WEST-NORTHWEST AND ACCELERATE IT. THE
TRACK GUIDANCE HAS SHIFTED A BIT TO THE WEST OVERNIGHT WITH LESS
SPREAD THAN EARLIER. THIS SHIFT TO THE LEFT SEEMS REASONABLE WITH
THE BUILDING RIDGE AND THE NHC FORECAST WILL BE MOVED IN THAT
DIRECTION...BUT STILL LIES TO THE RIGHT OF THE MODEL CONSENSUS.

Victoria, TX(Zone 9b)

heads up! prepare now, if you haven't already. Besides, even if it's just a heavy rainstorm, it's a good time to clean-up outside the house, and practice securing things that might blow into a window...

Thumbnail by AngelSong

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