TS Blanca

[*Mach*]

Blanca is located several hundred miles south and west of Cabo tracking west north west.

 

000

WTPZ43 KNHC 061444

TCDEP3

TROPICAL STORM BLANCA DISCUSSION NUMBER 2

NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP032009

800 AM PDT MON JUL 06 2009

 

THE FIRST FEW VISIBLE IMAGES INDICATE THAT THE CENTER OF BLANCA IS

EMBEDDED WITHIN WHAT COULD BE THE BEGINNINGS OF A CENTRAL DENSE

OVERCAST. IN ADDITION...A LONG BANDING FEATURE EXTENDS WELL SOUTH

AND SOUTHWEST OF THE MAIN CONVECTIVE MASS. THE LATEST DVORAK

T-NUMBERS FROM SAB AND TAFB ARE BOTH 2.5 AND CONFIRM THE RECENT

INCREASE IN ORGANIZATION. BASED UPON THE IMPROVED SATELLITE

PRESENTATION...THE INITIAL INTENSITY IS INCREASED TO 40 KT.

 

THE INITIAL MOTION REMAINS A SOMEWHAT UNCERTAIN 295/09...WITH RECENT

FIXES SUGGESTING A DECREASE IN FORWARD SPEED DURING THE LAST 12-24

HOURS. MODEL GUIDANCE AGREES THAT A BROAD BUT FLAT MID-LEVEL RIDGE

SHOULD REMAIN IN PLACE NORTH OF THE CYCLONE OVER THE SUBTROPICAL

EAST PACIFIC THE NEXT FEW DAYS. THIS FEATURE SHOULD STEER BLANCA

ON A MOSTLY WEST-NORTHWESTWARD COURSE OVER THE FORECAST PERIOD...

WITH A DECREASE IN FORWARD SPEED AND A SUBTLE TURN TO THE WEST

EXPECTED ONCE BLANCA BEGINS TO WEAKEN.

 

BLANCA IS CURRENTLY MOVING OVER 28C WATER IN A LOW SHEAR

ENVIRONMENT...AND INTENSIFICATION IS FORECAST IN THE NEAR-TERM. IN

FACT...THE SHIPS RAPID INTENSIFICATION INDEX INDICATES SOME

POTENTIAL FOR A MORE RAPID DEVELOPMENT. HOWEVER...THE CYCLONE

SHOULD REACH SUB-26C WATERS WITHIN 24 HOURS...AND THE OCEANIC HEAT

CONTENT WILL STEADILY DECREASE ALONG THE FORECAST PATH OF THE

STORM. EASTERLY SHEAR IS ALSO FORECAST TO INCREASE SLIGHTLY WITHIN

24 TO 36 HOURS. THESE TWO FACTORS SUGGEST THAT A HALT IN

DEVELOPMENT IS LIKELY AFTER 24-36 HOURS...FOLLOWED BY WEAKENING.

 

FORECAST POSITIONS AND MAX WINDS

 

INITIAL 06/1500Z 17.3N 112.1W 40 KT

12HR VT 07/0000Z 17.8N 113.5W 50 KT

24HR VT 07/1200Z 18.5N 115.3W 55 KT

36HR VT 08/0000Z 19.0N 117.0W 45 KT

48HR VT 08/1200Z 19.5N 118.7W 35 KT

72HR VT 09/1200Z 20.1N 121.2W 25 KT

96HR VT 10/1200Z 20.5N 123.5W 20 KT...REMNANT LOW

120HR VT 11/1200Z...DISSIPATED

 

$$

FORECASTER KIMBERLAIN/BROWN