000
AXPZ20 KNHC 290330
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC TUE JAN 29 2013

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 
0115 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
THE MONSOON TROUGH AXIS WAS ANALYZED FROM 02N79W TO 09N84W TO 
05N90W. ITCZ AXIS WAS ANALYZED FROM 05N90W TO 06N102W TO 05N110W 
TO 07N140W. SCATTERED MODERATE CONVECTION WAS WITHIN 240 NM N OF 
THE AXIS BETWEEN 122W AND 128W. 

...DISCUSSION...
A POSITIVELY TILTED UPPER-LEVEL TROUGH AXIS EXTENDS THROUGH THE 
INTERMOUNTAIN WESTERN U.S. TO 32N114W TO 25N128W TO 27N137W. A 
BROAD SOUTHWESTERLY UPPER JET LIES E OF THIS AXIS AND IS 
DIRECTING TROPICAL MOSITURE FROM THE ITCZ NEAR 125W THROUGH THE 
SOUTHERN BAJA CALIFORNIA PENINSULA INTO N CENTRAL MEXICO. 
SCATTERED MODERATE CONVECTION WAS NOTED IN THE REAR RIGHT 
QUADRANT OF THIS UPPER JET WITHIN 240 NM N OF THE ITCZ BETWEEN 
122W AND 128W. A COLD FRONT ASSOCIATED WITH THIS UPPER TROUGH 
WAS ANALYZED FROM NEAR LAS CRUCES NEW MEXICO TO HERMOSILLO 
MEXICO. THIS FRONT WILL CONTINUE EASTWARD THROUGH NORTHERN 
MEXICO THROUGH TUE. 

A STRONG DEEP-LAYER RIDGE HAS SET UP BEHIND THE TROUGH OVER AND 
N OF PACIFIC FORECAST WATERS. THE 1036 MB SUBTROPICAL HIGH 
ANALYZED NEAR 39N134W EXTENDS A RIDGE AXIS SOUTHEASTWARD THROUGH 
32N130W TO 20N110W. THE PRES GRADIENT BETWEEN THIS RIDGE AND THE 
FRONT OVER NW MEXICO IS FORCING A STRONG NW BREEZE ALONG THE 
BAJA CALIFORNIA NORTE COAST N OF 29N AS SEEN BY THE 2030 UTC 
OSCAT PASS AND 1800 UTC ASCAT PASS AS WELL AS SHIP 3FYB3 WHO 
REPORTED 26 KT NW WINDS AND 8 FT SEAS NEAR 20N117W AT 1900 UTC 
AND SHIP OZWA2 WHO REPORTED 27 KT AND 8 FT SEAS NEAR 30N122W AT 
1800 UTC. THESE WINDS ARE FORECAST TO DIMINISH TUE MORNING AS 
THE FRONT MOVES EASTWARD. SW OF THE RIDGE AXIS...FRESH TO STRONG 
TRADES WILL DOMINATE MUCH OF THE FORECAST AREA N OF THE ITCZ 
THROUGH WED.

NW SWELL CONTINUES TO MAKE ITS WAY THROUGH THE MAJORITY OF THE 
FORECAST WATERS...WITH PERIODS AS LONG AS 17-19 SECONDS. THIS NW 
SWELL WILL MIX WITH INCREASING NE WIND-WAVES GENERATED BY THE 
STRONG TRADE WINDS. SEAS IN THE TRADE WIND AREA ARE EXPECTED TO 
REACH 12 FT TUE AND WED.  

GAP WINDS...
GULF OF PAPAGAYO...STRONG ATLANTIC HIGH PRESSURE CENTERED OVER 
OFF THE CAROLINA COAST IS MAINTAINING MODERATE TO FRESH TRADE 
WINDS ACROSS THE SW CARIBBEAN THAT ARE FUNNELING INTO THE GULF 
OF PAPAGAYO. THE 1716 UTC OSCAT PASS SHOWED WINDS TO 25 KT 
DOWNWIND OF PAPAGAYO. THESE STRONG NE WINDS ARE EXPECTED TO 
DIMINISH ON WED AFTER THE EARLY MORNING PEAK DRAINAGE FLOW OFF 
THE LAND HAS ENDED.   

$$
SCHAUER