000
AXPZ20 KNHC 191530
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC WED JAN 19 2011

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...

THE INTERTROPICAL CONVERGENCE ZONE AXIS IS CENTERED ALONG 06N77W 
TO 04N90W TO 10N121W TO 08N140W. SCATTERED MODERATE TO STRONG 
WITHIN 60 NM N AND 30 NM S OF AXIS BETWEEN 78W AND 80W. 

...DISCUSSION...
HIGH PRES 1030 MB IS CENTERED NEAR 38N136W WITH RIDGE EXTENDING 
TO 20N123W. THE PRES GRADIENT BETWEEN THIS HIGH AND LOWER 
PRESSURE ASSOCIATED WITH THE ITCZ SUPPORTS FRESH TRADE WINDS TO 
20 KT FROM 14N TO 20N W OF 135W. THE SURFACE HIGH PRESSURE IS 
FORECAST TO REMAIN STATIONARY OVER THE NEXT 24 HOURS WHICH WILL 
MAINTAIN THIS AREA OF FRESH TRADES. THE PRESSURE GRADIENT 
BETWEEN THE SURFACE HIGH MENTIONED ABOVE AND THE CALIFORNIA 
COASTAL TROUGH IS SUPPORTING FRESH TO STRONG N TO NE WINDS. 
THESE WINDS ARE FORECAST TO REMAIN THROUGH 24 HOURS...THEN 
DIMINISH BELOW 20 KT WITHIN 48 HOURS. 

LARGE LONG PERIOD NW SWELLS WITH PERIODS OF 15-17 SEC ARE 
PRODUCING SEAS OF 8 TO 12 FT OVER THE NW PART OF THE AREA. A 
SECOND SET OF SWELLS WILL FURTHER INCREASE THE SEAS TO NEAR 15 
FT OVER THE FAR NW PART OF THE AREA BY FRI MORNING. 

GAP WINDS...
NEXT GULF OF TEHUANTEPEC EVENT IS FORECAST TO BEGIN ON FRI AS 
HIGH PRES BUILDS S ACROSS MEXICO AND THE WESTERN GULF OF MEXICO 
IN THE WAKE OF A COLD FRONT THAT MOVES THROUGH THE BAY OF 
CAMPECHE AND SOUTHEASTERN MEXICO. PRESENT INDICATIONS ARE THAT N 
WINDS THROUGH ISTHMUS OF TEHUANTEPEC ARE EXPECTED TO INITIATE AT 
20 TO 25 KT FRI MORNING...THEN REACH TO 30 KT IN THE AFTERNOON 
WITH THE POSSIBILITY OF A BRIEF EPISODE OF WINDS REACHING 
MINIMAL GALE FORCE.

WINDS ARE EXPECTED TO INCREASE TO 20 KT OVER THE FAR NORTHERN 
PORTION OF THE GULF OF CALIFORNIA BEGINNING ON THU AS STRONG 
HIGH PRES BUILDS OVER THE GREAT BASIN REGION. 

$$
AL