000
AXPZ20 KNHC 150355
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC THU MAR 15 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 
0330 UTC.

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

THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 05N84W TO 
00N111W. SCATTERED MODERATE ISOLATED CONVECTION IS WITHIN 60 NM
S OF THE AXIS BETWEEN  86W-91W AND BETWEN 94W-100W.

...DISCUSSION...

THE BROAD UPPER LEVEL TROUGH STRETCHED NE TO SW ACROSS WATERS N 
OF 20N IS BEING RELOADED WITH NORTHERN STREAM ENERGY WHICH IS 
SLOWING THE EASTWARD PROGRESS OF THE BROAD TROUGH. A SURFACE 
TROUGH ASSOCIATED WITH THIS BROAD TROUGH ALOFT CURRENTLY LIES 
OVER NW WATERS FROM 30N131W TO 26N136W AND A 1022 MB HIGH LIES 
TO ITS E NEAR 30N122W OFF THE COAST OF BAJA CALIFORNIA NORTE. 
THE WEAKENED SUBTROPICAL RIDGING OVER N WATERS IS SUPPORTING A 
SKINNY SWATH OF FRESH TRADE WINDS FROM 10N TO 14N W OF 120W. AS 
THE HIGH OFF THE BAJA BUILDS AND SHIFTS W THU INTO FRI...LOOK 
FOR TRADES TO EXPAND LATITUDINALLY. THE PRES GRADIENT BETWEEN 
THAT HIGH AND TROUGHING OVER NW MEXICO WILL ALLOW FRESH NW WINDS 
TO SET UP ALONG THE W COAST OF BAJA CALIFORNIA OVERNIGHT TONIGHT 
THAT WILL STRENGTHEN AND EXPAND SOUTHWARD ALONG THE PENINSULA 
THU AND REMAIN ON FRI. A NEW COLD FRONT WILL APPROACH THE NW 
PORTION OF THE FORECAST AREA FRI. NW SWELL WILL PROPAGATE AHEAD 
OF THIS FRONT...BRINGING SEAS TO 11 FT OVER NW WATERS BY FRI 
EVENING.

THE SOUTHERN STREAM UPPER JET ALONG 10N W OF 130W SPLITS AS IT 
MOVES EASTWARD...WITH THE SOUTHERN BRANCH CONTINUING ALONG 10N 
AND THE NORTHERN BRANCH DIRECTED INTO NW MEXICO...TRACKING ONTO 
THE LEADING EDGE OF THE AFOREMENTIONED BROAD TROUGH. THE 
NORTHERN BRANCH OF THE JET IS TRANSPORTING TROPICAL MOISTURE IN 
THE MID AND UPPER LEVELS THROUGH THE SOUTHERN GULF OF CALIFORNIA 
INTO THE RIO GRANDE VALLEY. THE RADAR AT GUASAVE MEXICO DOES NOT 
SHOW ANY SHOWER ACTIVITY ASSOCIATED WITH THIS BAND OF CLOUDS. 

GAP WINDS... 
THE GULF OF TEHUANTEPEC...FRESH TO STRONG N TO NE WINDS IN THE 
GULF OF TEHUANTEPEC REGION ARE EXPECTED TO PERSIST THROUGH FRI 
AFTERNOON BEFORE DIMINISHING TO BY 20 KT FRI EVENING. EARLY 
MORNING DRAINAGE FLOW TO 30 KT IS EXPECTED THE NEXT FEW 
MORNINGS. NO SIGNIFICANT CHANGE IN THE SYNOPTIC PATTERN IS 
EXPECTED OVER THE WESTERN GULF OF MEXICO UNTIL LATE FRI WHEN THE 
RIDGING THERE IS EXPECTED BEGIN ERODING.

THE GULF OF PAPAGAYO...FRESH TO STRONG TRADES ACROSS THE 
CARIBBEAN SEA CONTINUE TO FUNNEL NORTHEASTERLY GAP WINDS THROUGH 
CENTRAL AMERICA INTO THE GULF OF PAPAGAYO EXTENDING WESTWARD TO 
97W. THE 1506 UTC ASCAT PASS SHOWED FRESH TO STRONG WINDS BOTH 
IN THE IMMEDIATE VICINITY OF PAPAGAYO AND FARTHER SW NEAR 
09N90W. THE PRES GRADIENT BETWEEN THE AFOREMENTIONED HIGH PRES 
OFF BAJA CALIFORNIA NORTE AND THE ITCZ TO THE S IS FORCING THE 
AREA OF FRESH TO STRONG WINDS FARTHER W OF PAPAGAYO THAN USUAL.

THE GULF OF PANAMA...TRADES IN THE SW CARIBBEAN SEA WILL 
CONTINUE TO SUPPORT PULSES OF FRESH NORTHERLY FLOW ACROSS THE 
ISTHMUS OF PANAMA INTO THE GULF OF PANAMA. SEAS ARE EXPECTED TO 
REMAIN LESS THAN 8 FT WITH LITTLE CHANGE EXPECTED OVER THE NEXT 
48 HOURS.

$$
SCHAUER