000
WTNT42 KNHC 200856
TCDAT2
TROPICAL STORM BERTHA DISCUSSION NUMBER  69
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   AL022008
500 AM EDT SUN JUL 20 2008

ALTHOUGH THE CONVECTION IS NOT VERY DEEP...THE CLOUD PATTERN OF
BERTHA STILL LOOKS SOMEWHAT SYMMETRIC...I.E. TROPICAL...AND A SHIP
WITH CALL SIGN WDC6925 REPORTED 44 KT WINDS NOT FAR FROM THE
CENTER...WHICH IS ALSO INDICATIVE OF A TROPICAL STRUCTURE.  PHASE
SPACE ANALYSES FROM FLORIDA STATE UNIVERSITY USING THE GFS FORECAST
FIELDS INDICATE THAT BERTHA WILL BECOME AN EXTRATROPICAL CYCLONE
VERY SOON...PROBABLY NOT LONG AFTER 1200 UTC TODAY.  THE FORECAST
SHOWS BERTHA'S EXTRATROPICAL REMNANT BECOMING ABSORBED BY 72 HOURS
BUT GLOBAL MODELS FORECASTS SUGGEST THAT THIS EVENT COULD OCCUR
SOONER.  FOR NEXT DAY OR TWO...HOWEVER...THE POST-BERTHA CYCLONE
SHOULD REMAIN A FAIRLY POWERFUL EXTRATROPICAL STORM.

BERTHA IS ACCELERATING AND THE INITIAL MOTION IS NOW AROUND 035/26. 
AN ADDITIONAL INCREASE IN FORWARD SPEED IS EXPECTED AS THE CYCLONE
MOVES WITH THE FLOW ON THE SOUTHEAST SIDE OF A BROAD MID-LATITUDE
TROUGH...UNTIL THE SYSTEM MERGES WITH OR IS ABSORBED BY ANOTHER
LOW.  THE TRACK FORECAST IS IN GOOD AGREEMENT WITH THE MODEL
CONSENSUS AND SIMILAR TO THAT FROM THE PREVIOUS ADVISORY.
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      20/0900Z 48.5N  38.9W    60 KT
 12HR VT     20/1800Z 52.5N  34.5W    55 KT...EXTRATROPICAL
 24HR VT     21/0600Z 58.0N  28.0W    55 KT...EXTRATROPICAL
 36HR VT     21/1800Z 63.0N  21.0W    50 KT...EXTRATROPICAL
 48HR VT     22/0600Z 67.0N  15.0W    50 KT...EXTRATROPICAL
 72HR VT     23/0600Z...ABSORBED
 
$$
FORECASTER PASCH