000
AXPZ20 KNHC 170307
TWDEP 

TROPICAL WEATHER DISCUSSION   
NWS NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC TUE JAN 17 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 MONSOON TROUGH AXIS EXTENDS FROM 05N77W TO 05N95W. THE ITCZ 
AXIS EXTENDS FROM 05N95W TO BEYOND 06N140W. SCATTERED MODERATE 
CONVECTION WAS NOTED WITHIN 120 NM S OF AXIS BETWEEN 80W AND 
83W. SCATTERED MODERATE CONVECTION WAS NOTED WITHIN 150 NM N OF 
AXIS BETWEEN 115W AND 130W.

...DISCUSSION...

HIGH PRES 1030 MB IS CENTERED N OF THE AREA NEAR 37N133W WITH 
RIDGE EXTENDING SE TO NEAR 20N110W. THE PRESSURE GRADIENT 
BETWEEN THIS FEATURE AND LOWER PRESSURE IN THE VICINITY OF THE 
ITCZ IS MAINTAINING FRESH TRADEWINDS FROM 06N TO 18N W OF 130W 
AND FROM 08N TO 10N BETWEEN 125W AND 130W. THE HIGH PRESSURE 
CENTER WILL SHIFT SOUTHWARD AND CLOSER TO THE FORECAST AREA OVER 
THE NEXT 24 HOURS. THIS WILL EXPAND THE COVERAGE OF THE 
TRADEWINDS...AND BY WED AFTERNOON THE FRESH TRADEWINDS ARE 
EXPECTED TO COVER THE AREA FROM 07N TO 21N W OF 115W. THE 
PROXIMITY OF THE AREA OF HIGH PRESSURE AND A TROUGH OF LOW 
PRESSURE OVER MEXICO WILL TIGHTEN THE PRESSURE GRADIENT OVER THE 
SOUTHERN GULF OF CALIFORNIA AND OFF THE COAST OF CABO CORRIENTES 
MEXICO. THIS TIGHTENED PRESSURE GRADIENT WILL PRODUCE FRESH NW 
TO N WINDS BY TUE NIGHT.

A NW SWELL TRAIN THAT IS OVER THE FAR N PART OF THE FORECAST 
AREA. THIS SWELL IS EXPECTED TO BRING SIGNIFICANT WAVE HEIGHTS 
AS HIGH AS 10 FT TO WATERS N OF 20N THROUGH WED. 

GAP WINDS...

GULF OF TEHUANTEPEC...WITH WINDS VEERING OVER THE GULF OF 
MEXICO...WINDS FUNNELING THROUGH THE CHIVELA PASS INTO THE GULF 
OF TEHUANTEPEC HAVE DIMINISHED. CURRENTLY FRESH TO STRONG WINDS 
PREVAIL OVER THE GULF OF TEHUANTEPEC. WITH A DENSER AIR MASS 
OVER THE GULF OF MEXICO COMPARED WITH THAT OVER THE EASTERN 
PACIFIC...WINDS WILL CONTINUE TO FUNNEL INTO THE GULF OF 
TEHUANTEPEC FROM THE GULF OF MEXICO MAINTAINING FRESH 20 KT 
WINDS OVER THE GULF OF TEHUANTEPEC.

GULF OF PAPAGAYO...THE PRESSURE GRADIENT BETWEEN HIGH PRESSURE N 
OF THE CARIBBEAN AND LOWER PRESSURE OVER SOUTH AMERICA IS 
PRODUCING FRESH TO STRONG TRADEWINDS OVER THE FAR WESTERN 
CARIBBEAN. THESE WINDS AREA FUNNELING THROUGH GAPS IN THE THE 
TOPOGRAPHY OF NICARAGUA AND COSTA RICA INTO THE GULF OF 
PAPAGAYO. THIS WILL CONTINUE THROUGH AT LEAST WED EVENING WITH 
WINDS PEAKING DURING THE EARLY MORNING HOURS WITH THE ADDED 
COMPONENT OF NOCTURNALLY DRIVEN KATABATIC WINDS.

$$
AL