000
AXPZ20 KNHC 310307
TWDEP 

TROPICAL WEATHER DISCUSSION                                     
NWS NATIONAL HURRICANE CENTER MIAMI FL                         
0405 UTC SAT JAN 31 2015

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 
0100 UTC. 

...SPECIAL FEATURES...                                           
GULF OF TEHUANTEPEC GALE WARNING...A TIGHT PRESSURE GRADIENT 
ACROSS SOUTHERN MEXICO CONTINUES TO SUPPORT A LONG DURATION GALE 
EVENT IN THE GULF OF TEHUANTEPEC. WINDS TO 40 KT ARE EXPECTED TO 
CONTINUE THROUGH THE PERIOD OF PEAK DRAINAGE FLOW OFF THE 
MOUNTAINS SAT MORNING. THE PRESSURE GRADIENT IS BEGINNING TO 
WEAKEN HOWEVER...WITH WINDS IN THE SOUTHWESTERN GULF OF MEXICO 
EXPECTED TO VEER TO THE SOUTHEAST IN RETURN FLOW SAT. THE GALE 
FORCE WINDS IN THE GULF OF TEHUANTEPEC ARE FORECAST TO DIMINISH 
BY SAT AFTERNOON. WINDS WILL QUICKLY DROP BELOW A FRESH TO 
STRONG BREEZE BY SAT EVENING. A LARGE AREA OF 8-10 FT SEAS IN 
COMBINED LONG PERIOD NW SWELL AND NE SWELL FROM THE GULFS OF 
TEHUANTEPEC AND PAPAGAYO CONTINUES TO SPAN ACROSS MUCH OF THE 
AREA FROM 03N TO 14N BETWEEN 93W AND 109W. THIS AREA OF HIGHER 
SEAS WILL SUBSIDE SAT AFTERNOON THROUGH THE END OF THE FORECAST 
PERIOD SUN EVENING.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...            
THE ITCZ AXIS WAS ANALYZED FROM 05N90W TO 06N117W TO 05N140W. 
SCATTERED MODERATE CONVECTION WAS WITHIN 180 NM S OF THE AXIS 
BETWEEN 113W AND 118W.

...DISCUSSION...                                                
A DEEP LAYERED TROUGH IS MOVING INTO THE BAJA CALIFORNIA 
PENINSULA. BROKEN TO OVERCAST MULTILAYERED CLOUDS ARE FOUND N OF 
19N W OF 115W...INCLUDING OVER NW MEXICO AND THE SOUTHWESTERN 
PART OF THE UNITED STATES. LIGHTNING DATA SHOWS ACTIVE 
CONVECTION SW OF CABO SAN LUCAS...IN THE CENTRAL GULF OF 
CALIFORNIA...AND W OF THE SIERRA MADRE OCCIDENTAL FROM 20N-26N. 
RADARS OVER THE SW UNITED STATES SHOW WIDESPREAD PRECIPITATION 
ALONG THE BORDER W OF 105W. THE TROUGH WILL BE SLOW TO PROGRESS 
EASTWARD INTO MEXICO. PACIFIC MOISTURE WILL CONTINUE TO FEED 
INTO THE LEADING EDGE OF THE TROUGH WHICH WILL BE A FAVORABLE 
AREA FOR PRECIPITATION OVER THE WEEKEND. 

A SURFACE RIDGE EXTENDS FROM A 1024 MB HIGH PRESSURE CENTER THAT 
IS NEAR 34N132W THROUGH 32N132W...THEN SPLITS IN TWO WITH ONE 
AXIS EXTENDING SE TO 20N115W AND ANOTHER EXTENDING SW THROUGH 
25N140W. SCATTEROMETER PASSES PRIOR TO 1900 UTC SHOW FRESH TO 
STRONG NE TRADES S OF THESE RIDGE AXES OVER WATERS JUST N OF THE 
ITCZ AND W OF 120W. FRESH TO STRONG TRADE WINDS SHOULD LINGER 
OVER W WATERS THROUGH THE WEEKEND AS THE DRIVING HIGH PRESSURE 
CENTER SHIFTS SOUTHWARD.

GAP WINDS...                                                    
GULF OF PAPAGAYO...THE PRESSURE GRADIENT IN THE FAR WESTERN 
CARIBBEAN SEA AND ACROSS CENTRAL AMERICA IS WEAKENING. GALE 
WARNINGS HAVE BEEN DROPPED OVER THE GULF OF PAPAGAYO...BUT A 
FRESH TO STRONG BREEZE IS EXPECTED TO CONTINUE THROUGH SUN 
MORNING AND PULSE TO NEAR GALE STRENGTH WITH THE ASSISTANCE OF 
DRAINAGE FLOW OFF THE LAND IN THE LATE NIGHT HOURS TONIGHT AND 
THE EARLY MORNING HOURS SAT. AS MENTIONED IN THE SPECIAL 
FEATURES SECTION...SWELL FROM PAPAGAYO IS COMBINING WITH SEAS 
GENERATED FROM THE GALE IN THE GULF OF TEHUANTEPEC...BUT THE 
SWELL FROM PAPAGAYO WILL SUBSIDE AND SHRINK EASTWARD AS THE WIND 
SPEEDS DIMINISH THIS WEEKEND.

GULF OF PANAMA...THE PRESSURE GRADIENT ACROSS SOUTHERN CENTRAL 
AMERICA WILL CONTINUE TO BE STRONG ENOUGH TO ALLOW FRESH TO 
STRONG WINDS TO PULSE IN THE GULF OF PANAMA THROUGH SUN MORNING. 
SEAS TO 8 FT IN MIXED NE AND NW SWELL ARE EXPECTED AS FAR S AS 
03N.
 
$$ 
SCHAUER