000
AXPZ20 KNHC 040332
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL
0405 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0300 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... 

THE INTERTROPICAL CONVERGENCE ZONE IS ANALYZED THE EQUATOR ALONG 
109W TO 02N117W TO 02N128W THEN CROSSES THE EQUATOR AGAIN ALONG 
135W. THE ITCZ REMAINS UNUSUALLY FAR SOUTH...AND IS SOUTH OF THE 
EQUATOR BOTH EAST AND WEST OF THIS DESCRIBED POSITION. ISOLATED 
TO SCATTERED MODERATE CONVECTION NOTED S OF 04N BETWEEN 94W AND 
130W.

...DISCUSSION...

A STRONG AND WELL ESTABLISHED TROPICAL UPPER JET PREVAILS ACROSS 
PORTIONS OF THE LOCAL AREA...ORIGINATING AS UPPER LEVEL WLYS S 
OF 20N NEAR THE DATELINE...THEN BEGINNING TO TURN SW BETWEEN 
140-145W ASSOCIATED WITH A CENTRAL PACIFIC TROUGH. SWLY FLOW 
THEN MOVES ACROSS A TROPICAL RIDGE ACROSS THE TROPICAL EPAC 
ALONG 98W AND S OF 15N. UPPER LEVEL FLOW THEN BECOMES MORE ZONAL 
ACROSS THE N HALF OF MEXICO AS THE FLOW CONNECTS WITH A 
SUBTROPICAL JET FROM THE N CENTRAL GULF OF MEXICO NEWD ACROSS 
THE SE U.S. WHICH CONTINUES TO ENHANCE DEEP CONVECTION ALONG A 
COLD FRONT ACROSS THE GULF. A DEEP LAYER RIDGE WAS CENTERED OVER 
THE NE PACIFIC N OF 32N ALONG 130W. AN ASSOCIATED 1032 MB 
SURFACE HIGH IS CENTERED NEAR 40N132W. THE SURFACE PRESSURE 
GRADIENT BETWEEN THIS HIGH AND THE SIERRA MADRE OCCIDENTALES OF 
MEXICO ARE PRODUCING STRONG NWLY WINDS THROUGH THE GULF OF 
CALIFORNIA...WITH ISOLATED AREAS OF GALE FORCE WINDS. SEE GULF 
OF CALIFORNIA SECTION BELOW. FRESH N TO NE WINDS OFF THE WEST 
COAST OF BAJA CALIFORNIA HAVE SUBSIDED TO GENERALLY LESS THAN 20 
KT. TO THE SOUTH OF THE HIGH...FRESH TO STRONG NELY TRADEWINDS 
ARE FOUND FROM FROM 04N TO 21N W OF 123W. THE RIDGE NORTH OF THE 
AREA WILL WEAKEN AS IT SHIFTS EAST TO 130W SUNDAY AHEAD OF A 
DEEP LAYER TROUGH PUSHING ACROSS THE NORTH-CENTRAL PACIFIC NORTH 
OF THE HAWAIIAN ISLANDS. THE TRADEWIND FLOW S OF THE HIGH IS 
EXPECTED TO DIMINISH AS THE SURFACE HIGH WEAKENS TO 1022 MB AND 
SHIFTS SOUTH BY MONDAY MORNING. A MIX OF NE AND NW SWELL WITH 
SEA HEIGHTS OF 9 TO 11 FT COVERS MUCH OF THE AREA W OF 110W... 
BUT WILL SUBSIDE GRADUALLY THROUGH LATE SUNDAY.

VERY LIGHT WINDS PREVAIL ACROSS THE FAR EASTERN WATERS E OF 
100W...AND PERSISTENT NE WINDS ACROSS THE TRADEWIND ZONE HAVE 
PUSHED THE ITCZ TO NEAR THE EQUATOR...WHERE IT HAS UNDULATED 
DURING THE PAST FEW DAYS. SST'S HAVE WARMED ACROSS THE EASTERN 
EQUATORIAL PACIFIC IN THE LAST FEW WEEKS...AND ARE NOW ABOVE 
NORMAL E OF 120W.

GAP WINDS...

GULF OF TEHUANTEPEC...A STRONG COLD FRONT PRESENTLY MOVING 
SOUTHEASTWARD ACROSS THE GULF OF MEXICO IS EXPECTED TO REACH THE 
BAY OF CAMPECHE TONIGHT AND RAPIDLY INDUCE NLY WINDS ACROSS THE 
CHIVELA PASS AND THROUGH THE GULF OF TEHUANTEPEC SHORTLY AFTER 
MIDNIGHT...INCREASING TO GALE FORCE OVERNIGHT AND THEN CONTINUE 
TO INCREASE TO NEAR 55 KT SUNDAY MORNING. A LARGE AND ELONGATE  
PLUME OF N TO NE WINDS WILL SPREAD DOWNSTREAM FROM TEHUANTEPEC 
AND BUILD VERY LARGE SEAS...AS HIGH AS 20-22 FT IN THE AREA OF 
50 KT WINDS. GALE FORCE WINDS AND HIGHER ARE EXPECTED TO 
CONTINUE ACROSS THIS AREA THROUGH MONDAY EVENING BEFORE 
DIMINISHING.

GULF OF CALIFORNIA...THE A 1032 MB HIGH OFFSHORE OF THE N 
CALIFORNIA COAST ALONG 40W IS INDUCING A STRONG PRESSURE 
GRADIENT THROUGH THE GULF OF CALIFORNIA...AND STRONG NWLY FLOW 
CONTINUES THROUGH THE ENTIRE LENGTH OF THE GULF. RECENT 
SCATTEROMETER PASSES THIS AFTERNOON HAVE SHOWN 25-30 KT WIND 
COVERING MOST OF THE GULF...WITH A FEW SMALLER AREAS OF GALE 
FORCE WINDS...ESPECIALLY ALONG THE INNER E COAST OF BAJA...AS 
WELL AS NLY GALES ROUNDING PUNTA ARENA NEAR THE SOUTHERN TIP OF 
THE PENINSULA. GALES ARE EXPECTED TO CONTINUE OVERNIGHT BEFORE 
WINDS DIMINISH BELOW GALE FORCE SUNDAY MORNING. SEAS HAVE BUILT 
TO 10 FT ACROSS S PORTIONS OF THE GULF AND WILL SLOWLY SUBSIDE 
TO BELOW 8 FT ON MONDAY.

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

$$
STRIPLING