000
AXPZ20 KNHC 011505
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC FRI FEB 1 2008

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W. 

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1500 UTC.
 
...ITCZ...

ITCZ AXIS IS CENTERED ALONG 6N77W 4N90W 6N100W 4N115W 8N140W. NO 
SIGNIFICANT CONVECTION.

...DISCUSSION...

A PROGRESSIVE LONGWAVE PATTERN CONTINUES TO IMPACT MUCH OF NORTH 
AMERICA BUT THE ZONE OF STRONGEST WINDS HAS SHIFTED A LITTLE 
FARTHER N TO THE CENTRAL PART OF THE UNITED STATES AS COMPARED 
TO YESTERDAY. STILL...A TIGHT HEIGHT GRADIENT EXISTS OVER 
NORTHERN PORTIONS OF THE DISCUSSION AREA N OF 20N WHICH IS 
ALLOWING 50-70 KT WINDS ASSOCIATED WITH THE SUBTROPICAL JET TO 
MOVE EASTWARD ACROSS NORTHERN MEXICO. A CLOSED UPPER LOW NE OF 
HAWAII NEAR 27N150W IS STILL PRODUCING AN AREA OF DIFFLUENCE TO 
ITS E...AND THUS THERE IS A BROKEN TO OVERCAST CANOPY OF CIRRUS 
N OF 14N W OF 120W. FARTHER E...A WEAK MID/UPPER TROUGH IS 
EMBEDDED WITHIN THE FAST-MOVING FLOW FROM NE MEXICO TO 16N112W 
WHICH IS FOSTERING UPPER LEVEL CONFLUENCE AND SUBSIDING AIR E OF 
115W ACROSS MOST OF MEXICO.

IN THE TROPICS...AN UPPER TROUGH IS LOCATED ALONG 126W S OF 10N 
OTHERWISE MUCH OF THE FLOW IS ZONAL WESTERLY. A SURFACE TROUGH 
LOCATED JUST W OF 140W IS TIGHTENING THE PRES GRADIENT A BIT 
ALONG ITS NORTHERN FRINGE AND THE TRADE WINDS HAVE INCREASED TO 
25-30 KT IN AN AREA FROM 15N TO 19N W OF 130W.

A COLD FRONT HAS SURGED SWD OVER THE GULF OF MEXICO AND HAS 
REACHED THE ISTHMUS OF TEHUANTEPEC WITH WINDS JUST BEGINNING TO 
INCREASE OVER THE GULF OF TEHUANTEPEC. A GALE WARNING REMAINS IN 
EFFECT FOR THE GULF OF TEHUANTEPEC WHERE WINDS ARE EXPECTED TO 
REACH GALE FORCE BY 1800 UTC AND LIKELY INCREASE TO 40 KT BY 
EVENING. THE PULSE WILL BE SHORT-LIVED HOWEVER...AND WINDS ARE 
EXPECTED TO DROP BELOW GALE FORCE BY SAT MORNING THEN COMPLETELY 
BELOW 20 KT BY SAT EVENING. NE WINDS TO 20 KT CONTINUE OVER THE 
GULF OF PAPAGAYO BUT COULD INCREASE TO 20-25 KT WITHIN 24 HRS AS 
HIGH PRES BUILDS TO THE N. THIS TOO SHOULD BE SHORT-LIVED AND 
WILL DIMINISH A BIT BY SUN MORNING.

$$
BERG