| HOME | ARCHIVES | FORECASTS | IMAGERY | ABOUT NHC | RECONNAISSANCE |

---

Tropical Depression BLANCA (Text)

ZCZC MIATCDEP3 ALL
TTAA00 KNHC DDHHMM
TROPICAL DEPRESSION BLANCA DISCUSSION NUMBER  10
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   EP032009
800 AM PDT WED JUL 08 2009
 
AN 0532 UTC ASCAT PASS INDICATED A SMALL AREA OF NEAR TROPICAL STORM
FORCE WINDS JUST NORTH OF THE CENTER...WHICH WAS COINCIDENT WITH
THE TIME WHEN ALL DEEP CONVECTION BEGAN TO COLLAPSE.  ALTHOUGH THE
CIRCULATION REMAINS WELL-DEFINED...BLANCA IS NOW A TIGHT SWIRL OF
LOW CLOUDS MOVING OVER 22-23C SEA SURFACE TEMPERATURES.  BASED ON
THE EARLIER ASCAT PASS...THE INITIAL INTENSITY IS KEPT AT 30 KT FOR
THIS ADVISORY...BUT THIS COULD BE GENEROUS GIVEN THE CURRENT
WEAKENING TREND.  THE CYCLONE WILL LIKELY BECOME A REMNANT LOW
LATER TODAY.
 
THE INITIAL MOTION IS 290/10...A LITTLE TO THE LEFT OF THE PREVIOUS
ESTIMATE. A MID- TO UPPER-LEVEL RIDGE EXTENDING WESTWARD FROM
NORTHERN MEXICO HAS BEEN STEERING BLANCA ON A WEST-NORTHWEST TO
NORTHWEST HEADING FOR SEVERAL DAYS NOW.  HOWEVER...THE RECENT
DISSIPATION OF ALL DEEP CONVECTION HAS MADE BLANCA A SHALLOW SYSTEM
WHOSE MOTION IS BEING CONTROLLED BY A WEAKER...LOW-LEVEL FLOW.
GIVEN THE RECENT MORE WESTWARD MOTION...THE FORECAST TRACK IS
NUDGED SLIGHTLY TO THE LEFT AND IS ON LEFT SIDE OF THE GUIDANCE
ENVELOPE.
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      08/1500Z 20.8N 120.1W    30 KT
 12HR VT     09/0000Z 21.5N 121.2W    25 KT...REMNANT LOW
 24HR VT     09/1200Z 22.0N 122.5W    20 KT...REMNANT LOW
 36HR VT     10/0000Z 22.5N 124.0W    20 KT...REMNANT LOW
 48HR VT     10/1200Z...DISSIPATED
 
$$
FORECASTER KIMBERLAIN/AVILA
 
NNNN