000
AXPZ20 KNHC 150938
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC THU JAN 15 2009

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

BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0815 UTC.

...ITCZ...

ITCZ CAN BE FOUND ALONG A LINE FROM 06N77W TO 06N95W TO 07N120W 
TO 08N130W TO 06N140W. SCATTERED MODERATE CONVECTION LIES WITHIN 
30 NM OF AXIS FROM 125W TO 128W.

...DISCUSSION...

NEAR SHORE...
THE QUIKSCAT PASS FROM 0058 UTC CONFIRMS GALE CONDITIONS IN THE 
GULF OF TEHAUNTEPEC.  LITTLE CHANGE IS EXPECTED HERE...WITH A 
SUSTAINED MINIMAL GALE...UNTIL THIS EVENING WHEN A NEW JOLT OF 
ARCTIC AIR IS EXPECTED TO RACE SOUTHWARD THROUGH THE GULF OF 
MEXICO. STORM FORCE WINDS ARE EXPECTED FROM THIS EVENING INTO 
SAT AS THE ARCTIC AIR FUNNELS THROUGH THE ISTHMUS OF 
TEHUANTEPEC.  

IN TURN...WINDS IN THE GULF OF PAPAGAYO ARE EXPECTED TO INCREASE 
TO JUST BELOW GALE FORCE ON FRI AS THIS ARCTIC AIRMASS MAKES ITS 
WAY FARTHER SOUTH.  IN THE MEANTIME...THE STRONG TRADE WINDS IN 
THE CARIBBEAN CONTINUE TO SEEP THROUGH COSTA RICA/NICARAGUA INTO 
THE GULF OF PAPAGAYO...WITH WINDS CURRENTLY IN THE 20 TO 25 KT 
RANGE AS CONFIRMED BY THE 0348 UTC ASCAT PASS.

ELSEWHERE...
THE BIGGEST HAZARD OVER THE NEXT TWO DAYS WILL BE THE BUILDING 
SEAS AND LONG PERIOD NW SWELL EMANATING FROM NW OF FORECAST 
WATERS MOVING INTO THE FORECAST AREA LATER TODAY. SEAS ARE 
EXPECTED TO BUILD AS HIGH AS 14 TO 16 FT OVER NW WATERS BY LATE 
FRI AFTERNOON WITH THE SWELL MOVING RAPIDLY SOUTHEASTWARD INTO 
THE AREA. THE LEADING EDGE OF THE LONG PERIOD SWELL...GENERALLY 
IN THE 18 TO 20 SECOND RANGE...IS EXPECTED TO REACH THE W COAST 
OF BAJA CALIFORNIA ON SAT.  WINDS OVER FAR NW WATERS ARE 
EXPECTED TO INCREASE TO THE 20 TO 30 KT RANGE STARTING LATE 
TODAY.

SCATTERED MODERATE CONVECTION...SUPPORTED BY STRONG UPPER LEVEL 
DIFFLUENCE WHERE THE LEADING EDGE OF THE MID TO UPPER LEVEL 
TROUGH ALONG 135W MEETS THE LEFT FRONT QUADRANT OF THE WESTERLY 
UPPER JET S OF 08N AND W OF 125W...CAN CURRENTLY BE FOUND FROM 
11N TO 17N BETWEEN 123W AND 133W.  THE MID TO UPPER LEVEL TROUGH 
IS NOT EXPECTED TO MOVE MUCH THIS PERIOD.  BY THE WEEKEND...IT 
IS EXPECTED TO TRANSLATE TO THE SURFACE WITH A TROUGH EXPECTED 
IN THE VICINITY OF 125W TO 130W BETWEEN 08N AND 18N.  WINDS ARE 
EXPECTED TO BE NEAR 20 KT...WITH SEAS ELEVATED TO 9 FT BEFORE 
THE AFOREMENTIONED NW SWELL WASHES THROUGH THE REGION ON SAT.

$$
SCHAUER CLARK