000
AXPZ20 KNHC 110932
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC FRI FEB 11 2011

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 
0915 UTC.

...ITCZ...

THE INTERTROPICAL CONVERGENCE ZONE AXIS IS ANALYZED FROM 05N77W 
TO 04N105W TO 09N125W THEN RESUMES NEAR 04N134W TO 03N140W. NO 
SIGNIFICANT CONVECTION IS NOTED.

...DISCUSSION...

ALOFT...A STRONGLY POSITIVELY TILTED MID TO UPPER LEVEL TROUGH
AXIS EXTENDS FROM SW ARIZONA THROUGH 25N129W TO A CYCLONIC 
CIRCULATION CENTERED NEAR 20N139W. THE SUBTROPICAL JET WITH CORE 
SPEEDS OF 65 TO 80 KT E OF THE TROUGH CONTINUES TO ADVECT MID TO 
UPPER LEVEL MOISTURE ACROSS THE SOUTHERN BAJA CALIFORNIA 
PENINSULA AND NW MEXICO.

AT THE SURFACE...1024 MB HIGH PRES CENTERED NEAR 39N130W NW OF 
SAN FRANCISCO BAY IS EMBEDDED WITHIN A RIDGE AXIS WHICH EXTENDS 
SOUTHWESTWARD ACROSS THE NW PORTION OF THE DISCUSSION AREA TO 
JUST EAST OF THE HAWAIIAN ISLANDS NEAR 20N144W. THE HIGH AND 
RIDGE AXIS WILL MIGRATE SLOWLY E THROUGH THE NEXT 24 HOURS. NW 
SWELL OF 8 TO 11 FT ENCOMPASSES THE MAJORITY OF THE AREA N OF 
10N AND W OF 115W. THIS SWELL TRAIN WILL GRADUALLY DECAY AS IT 
PROPAGATES SE THROUGH THE NEXT 48 HOURS. 

A SURFACE TROUGH ANALYZED FROM 13N124W TO 04N130W IS MOVING W 
AROUND 10 TO 15 KT. SCATTERED MODERATE TO STRONG CONVECTION IN 
ASSOCIATION WITH THE TROUGH IS NOTED FROM 07N TO 12N BETWEEN 
121W AND 126W. THE TROUGH HAS TIGHTENED THE PRES GRADIENT 
BETWEEN THE HIGH AND THE ITCZ WITH A BELT OF 20 TO 25 KT NE TO E 
TRADES OCCURRING FROM 04N TO 13N W OF THE TROUGH. THESE TRADES 
WILL SHIFT WESTWARD IN TANDEM WITH THE TROUGH OVER THE NEXT 48 
HOURS GRADUALLY WEAKENING THROUGH THE END OF THE FORECAST PERIOD.

GAP WINDS...
GULF OF TEHUANTEPEC...COLD AIR CONTINUES TO SURGE THROUGH THE 
CHIVELA PASS ACROSS THE ISTHMUS OF TEHUANTEPEC WITH GALE FORCE 
WINDS OCCURRING DOWNWIND IN THE GULF OF TEHUANTEPEC. WINDS ARE 
DIMINISHING AT LAND-BASHED STATION IXTEPEC IN OAXACA MEXICO AND 
EXPECT THE GALE WARNING TO BE ALLOWED TO EXPIRE AT 12 UTC. A 
REINFORCING SURGE OF COLD AIR WILL ARRIVE LATER TODAY WITH A 
SECOND GALE WARNING BEGINNING AT 00 UTC SAT AND CONTINUING 
THROUGH AT LEAST 48 HOURS. WINDS WILL INCREASE TO 40 TO 45 KT BY 
SAT AFTERNOON WITH SEAS BUILDING TO UP TO 18 FT. WINDS MAY 
INCREASE TO STORM FORCE FOR A BRIEF PERIOD ALTHOUGH WILL REFRAIN 
FROM UPGRADING TO A STORM WARNING FOR A FEW MORE MODEL RUNS.

GULF OF PAPAGAYO...WINDS WILL CONTINUE TO PULSE TO 20 KT DURING 
THE NEXT 24 HOURS MAINLY DURING THE MORNING HOURS WITH ENHANCED 
DRAINAGE FLOW OFF THE CENTRAL AMERICA LANDMASS. EASTERLY TRADE 
WINDS WILL INCREASE IN THE WESTERN CARIBBEAN SEA BY 48 HOURS 
WHICH WILL ALLOW FOR WINDS TO INCREASE TO 20 TO 25 KT IN THE 
GULF OF PAPAGAYO.

GULF OF PANAMA...EASTERLY TRADE WINDS IN THE CARIBBEAN SEA ARE 
EXPECTED TO INCREASE AND SPREAD WESTWARD FRI NIGHT WITH 
NORTHERLY DRAINAGE FLOW TO 20 KT ACROSS THE ISTHMUS OF PANAMA 
SPILLING INTO THE GULF OF PANAMA REMAINING N OF 06N BETWEEN 78W 
AND 80W.

GULF OF CALIFORNIA...A TIGHT PRES GRADIENT BETWEEN HIGH PRES 
OVER THE U.S. ROCKY MOUNTAINS AND 1007 MB LOW PRES NEAR 23N104W 
OVER W CENTRAL MEXICO IS GENERATING 20 TO 25 KT NW TO N WINDS 
WHICH ARE FUNNELING THROUGH THE GULF OF CALIFORNIA. WINDS WILL 
DIMINISH TO 20 KT FRI NIGHT REMAINING 20 KT THROUGH 48 HOURS AS 
THE PRES GRADIENT GRADUALLY WEAKENS.

$$
LEWITSKY