Subject: Pacific-EN: Tropical Depression Hilda Discussion Number 18

From: SIU Weather Processor <[email-masked]>
Date: Thu, 14 Aug 1997 03:35:48 +1900

769
WTPZ45 KNHC 140835
TCDEP5
TROPICAL DEPRESSION HILDA DISCUSSION NUMBER  18
NATIONAL WEATHER SERVICE MIAMI FL
2 AM PDT THU AUG 14 1997

SATELLITE IMAGERY SHOWS A WEAKENED SYSTEM WITH VERY LITTLE DEEP
CONVECTION REMAINING.  HILDA IS DOWNGRADED TO A TROPICAL DEPRESSION
IN AGREEMENT WITH LATEST DVORAK ESTIMATES FROM SAB AND TAFB.  THE
SHEAR FROM THE LARGE UPPER-LEVEL LOW TO THE NORTHWEST BEGAN TAKING
ITS TOLL ON HILDA YESTERDAY.  ALTHOUGH THE AVIATION MODEL FORECASTS
THE UPPER-LEVEL LOW TO WEAKEN AND MOVE NORTHWESTWARD AWAY FROM
HILDA...THE TROPICAL CYCLONE HAS ALREADY WEAKENED SO MUCH THAT IT IS
DOUBTFUL THAT IT CAN MAKE A COMEBACK.  A TROPICAL DISTURBANCE
CENTERED IN THE VICINITY OF 12N113W MAY BE DISRUPTING SOME OF THE
INFLOW INTO HILDA.  ALSO...THE DEPRESSION WILL BE MOVING OVER COOLER
WATERS BEYOND 24 HOURS...SO CONTINUED WEAKENING IS FORECAST UNTIL
THE SYSTEM IS DECLARED DISSIPATED IN A COUPLE OF DAYS IF NOT SOONER.

CIRRUS CLOUDS ARE CURRENTLY OBSCURING THE LOW-LEVEL CENTER...MAKING
THE INITIAL POSITIONING DIFFICULT.  THE MOST EVIDENT TURNING IN
INFRARED IMAGERY APPEARS TO BE AT MID LEVELS...AND IS LOCATED
SOMEWHAT TO THE NORTH OF OUR LOW-LEVEL CENTER ESTIMATE WHICH HAS
CONTINUITY FROM THE LAST LIGHT VISIBLE PICS.  BEST GUESS AT INITIAL
MOTION IS 290/10.  THE FORECAST TRACK MAY HAVE TO BE ADJUSTED ON THE
NEXT ADVISORY IF THE CENTER FIX ON VISIBLE PICS RESULTS IN ANY
SIGNFICANT RELOCATION OF THE CENTER.  THE CURRENT TRACK MERELY
UPDATES THE PREVIOUS ADVISORY PACKAGE WHICH MAINTAINS THE
WEST-NORTHWESTWARD MOTION IN RESPONSE TO THE LOW-LEVEL STEERING.

MAYFIELD

FORECAST POSITIONS AND MAX WINDS

INITIAL     14/0900Z 15.7N 126.3W    30 KTS
12HR VT     14/1800Z 16.2N 127.7W    30 KTS
24HR VT     15/0600Z 16.8N 129.6W    30 KTS
36HR VT     15/1800Z 17.5N 131.5W    25 KTS...DISSIPATING
48HR VT     16/0600Z 18.2N 133.5W    20 KTS...DISSIPATING

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
To unsubscribe from WX-TROPL send e-mail to [email-masked] with
"unsub wx-tropl" in the body of your message.  For help with the
WX-TROPL or WX-TALK discussion groups write to [email-masked] or see
http://www.inlink.com/~landmb/intro.html.  For more information on
tropical weather products, see the NCEP Products Homepage at
http://www.nhc.noaa.gov/nhcprod.html.