000
AXPZ20 KNHC 041612
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC SUN MAR 04 2012
 
TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W. THE FOLLOWING INFORMATION IS 
BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND 
METEOROLOGICAL ANALYSIS.

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

THE MONSOON TROUGH STARTS NEAR THE BORDER OF PANAMA AND COLOMBIA 
NEAR 7N78W TO 0586W. THE ITCZ CONTINUES FROM 04N88W TO 
00N100W...AND FROM 01N111W TO 02N115W TO 00N129W. SCATTERED 
MODERATE TO ISOLATED STRONG CONVECTIVE PRECIPITATION IS TO THE 
SOUTH OF 03N BETWEEN 98W AND 102W...AND WITHIN 30 NM RADIUS OF 
3N113W.

SCATTERED MODERATE CONVECTIVE PRECIPITATION IS FROM 03N TO 07N 
BETWEEN 81W AND 88W...FROM 16N TO 18N BETWEEN 129W AND 131W...
AND FROM 19N TO 28N BETWEEN 125W AND 129W. 

...DISCUSSION...

MIDDLE LEVEL TO UPPER LEVEL ANTICYCLONIC WIND FLOW COVERS
THE AREA THAT IS TO THE EAST OF 120W. AN UPPER LEVEL TROUGH 
PASSES THROUGH 30N136W TO 15N132W TO 4N123W. A BROAD AREA OF 
FRESH TRADE WINDS BETWEEN ROUGHLY 05N TO 20N TO THE WEST OF
120W WILL DIMINISH IN INTENSITY AND AREAL EXTENT AS THE SURFACE 
HIGH WEAKENS AND SHIFTS SOUTHWARD. THE SURFACE PRESSURE WILL
BUILD BY THE MIDDLE OF THE WEEK AS THE DEEP LAYER RIDGE BECOMES 
RE-ESTABLISHED IN THE NORTHWESTERN PACIFIC OCEAN ALONG 140W.
THE TRADE WINDS REBOUND FROM 05N TO 20N W OF 110W BY WEDNESDAY 
ACCORDINGLY. A BROAD AREA OF NORTHWESTERLY SWELL MIXING WITH
FRESHER NORTHEASTERLY SWELL IN THE AREA OF TRADES WILL DECAY
GRADUALLY THROUGH WEDNESDAY.

GAP WINDS...

GULF OF CALIFORNIA...A 1004 MB LOW PRES IS CENTERED OVER W 
CENTRAL MEXICO WITH A SURFACE TROUGH EXTENDING ALONG THE SIERRA 
MADRE OCCIDENTAL OVER NW MEXICO. NW GALES PERSIST THIS MORNING 
OVER THE CENTRAL GULF OF CALIFORNIA FROM 24N TO 27N...BETWEEN 
THE SURFACE TROUGH TO THE EAST...AND 1032 MB SURFACE HIGH PRES 
OFF THE CALIFORNIA COAST. THESE WINDS DIMINISH BELOW GALE FORCE 
THIS MORNING...AND BELOW 20 KT OVER THE NEXT 24 HOURS AS THE 
PRES GRADIENT LOOSENS BETWEEN THESE WEAKENING FEATURES.

GULF OF TEHUANTEPEC...A COOL AIR MASS THAT IS ASSOCIATED WITH
A 1028 MB SURFACE HIGH PRESSURE CENTER...THAT IS IN EAST CENTRAL 
MEXICO...IS PUSHING STRONG GAP WIND FLOW THROUGH THE CHIVELA 
PASS TODAY AND INTO THE GULF OF TEHUANTEPEC. THE LATEST WINDS AT 
SALINA CRUZ ON THE SOUTHERN TERMINUS OF THE ISTHMUS HAVE SHOWN
AT LEAST ONE OBSERVATION OF NEAR 35 KT. THE STRONG HIGH PRESSURE
AND THE COOLER AIR FILTERING SOUTHWARD WILL HELP TO PUSH THE 
WIND SPEEDS IN THE GULF OF TEHUANTEPEC TO STORM FORCE THIS 
AFTERNOON...WITH SEAS BUILDING TO 21 FT. A LONG PLUME OF WINDS 
OF 20 TO 30 KT WILL PUSH SOUTHWARD AND THEN SOUTHWESTWARD...
REACHING AS FAR AS 10N100W BY TUESDAY. NORTHEASTERLY SWELL WILL
BUILD IN THE PLUME...MIXING WITH LONGER PERIOD NORTHWESTERLY 
SWELL THROUGH THE MIDDLE OF THE WEEK. THE WINDS WILL DIMINISH
TO GALE FORCE BY TUESDAY...AND THE TO LESS THAN GALE FORCE ON 
WEDNESDAY. 

GULF OF PAPAGAYO...THE WIND SPEEDS THROUGH THE GULF OF PAPAGAYO
WILL INCREASE QUICKLY TO 20 TO 25 KT OVERNIGHT SUNDAY...AND THEN 
RANGE FROM 20 TO 30 KT BY MONDAY MORNING. THESE WINDS WILL 
SPREAD SOUTHWESTWARD AND DOWNWIND OF THE GULF BEYOND 300 NM
BY MIDDAY MONDAY...WITH SEAS BUILDING TO 12 FT. THIS WILL HAPPEN 
AS THE PRESSURE GRADIENT THAT IS BEHIND THE GULF OF MEXICO COLD 
FRONT EVENTUALLY EXPANDS ACROSS CENTRAL AMERICA SUNDAY NIGHT.
THESE WINDS WILL SPREAD SW AND DOWNWIND OF THE GULF BEYOND 300 
NM BY MIDDAY MONDAY...WITH SEAS BUILDING TO 12 FT. 

$$
MT