000
AXPZ20 KNHC 020334
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC SAT MAR 02 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 
0200 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
THE MONSOON TROUGH AXIS WAS ANALYZED FROM 05N77W TO 07N85W TO 
01N110W. THE ITCZ AXIS WAS ANALYZED FROM 01N110W TO 04N140W. 
ISOLATED MODERATE CONVECTION WAS WITHIN 150 NM N AND 90 NM S OF 
THE AXIS BETWEEN 80W AND 85W. SCATTERED MODERATE CONVECTION WAS 
WITHIN 210 NM N OF THE AXIS BETWEEN 120W AND 125W.

...DISCUSSION...
GULF OF TEHUANTEPEC...NORTHERLY WINDS AT GALE FORCE SHOULD 
STRENGTHEN TO A MINIMAL STORM AROUND MIDDAY ON SAT BEFORE 
DIMINISHING TO A STRONG GALE AGAIN AROUND MIDDAY SUN. THE 
SOUTHERN EXTENT OF 25 KT WINDS WILL REACH AS FAR AS 08N ON SUN. 
MOST IMPRESSIVE IS THE LARGE AREA OF N SWELL PROPAGATING S FROM 
THE TEHUANTEPEC COAST WHICH WILL RESULT IN SEAS 8 FT OR GREATER 
EVENTUALLY COVERING THE PACIFIC WATERS FROM 02N TO 14N BETWEEN 
92W AND 109W BY SUN EVENING.

GULFS OF PAPAGAYO AND FONSECA...NORTHEASTERLY WINDS WILL BEGIN 
TO SURGE THROUGH THE GULFS OF PAPAGAYO AND FONSECA OVERNIGHT SAT 
NIGHT AND QUICKLY SHIFT S TO THE GULF OF PAPAGAYO SUN. WIND 
WAVES AND SWELL HERE WILL MIX WITH SWELL FROM TEHUANTEPEC AND 
BRING SEAS TO 12 FT ON SUN. LOOKING AHEAD...GUIDANCE SUGGESTS 
THE NE FLOW WILL INCREASE TO A MINIMAL GALE JUST DOWN STREAM OF 
THE GULF OF PAPAGAYO ON MON.

GULF OF CALIFORNIA...THE 1852 UTC OSCAT PASS SHOWED NW WINDS 
NEAR THE SE TIP OF THE BAJA CALIFORNIA PENINSULA CONTINUE TO BE 
30 KT. WINDS ARE GENERALLY ENHANCED HERE AND ARE BELIEVED TO BE 
IN THE 20-25 KT RANGE ELSEWHERE IN THE GULF S OF 29N. N SWELL IS 
PROPAGATING FROM THE GULF INTO THE PACIFIC WATERS NEAR ITS 
MOUTH...WITH SEAS TO 9 FT FOUND AS FAR S AS 18N. WINDS WILL 
DIMINISH TO A MODERATE TO FRESH BREEZE ON SAT. SEAS WILL 
GRADUALLY SUBSIDE DURING THIS TIME...FALLING BELOW 8 FT BY 
MIDDAY SAT. 

A NEGATIVELY TILTED...SHARP UPPER TROUGH OVER W WATERS IS BEING 
OVERTAKEN BY A NEW...AMPLIFYING UPPER TROUGH APPROACHING FROM 
THE NW. A WIDE SOUTHERLY UPPER JET W OF 130W LIES ON THE LEADING 
EDGE OF THIS BROAD TROUGHING AND IS DIRECTING MOISTURE FROM THE 
ITCZ OVER MUCH OF THE AREA W OF 127W. MUCH OF THIS MOISTURE IS 
MANIFESTED AS MULTIPLE-LAYER CLOUDS WITH SCATTERED SHOWERS. THE 
REAR RIGHT QUADRANT OF THE JET IS ENHANCING THE MOST VIGOROUS 
CONVECTION NEAR A SURFACE TROUGH FROM 12N134W TO 06N135W. THE 
NEW UPPER TROUGH WILL AMPLIFY W OF THE AREA AND BE POSITIVELY 
TILTED...REORIENTING THE UPPER JET AND DISSIPATING THE SURFACE 
TROUGH. PRECIPITATION IS EXPECTED TO GRADUALLY WANE OVER WESTERN 
WATERS THE NEXT FEW DAYS AS A RESULT.

THE 1030 MB SUBTROPICAL HIGH IS CENTERED NEAR 38N128W. THE HIGH 
HAS BEEN IMPEDED ON BY A COLD FRONT APPROACHING FROM THE 
W...WEAKENING THE SUBTROPICAL RIDGING OVER THE FORECAST AREA. 
THE RIDGE AXIS EXTENDS SOUTHWARD FROM THE HIGH TO NEAR 25N128W. 
PRIMARILY MODERATE TO FRESH NE TRADE WINDS LIE SW OF THE RIDGE 
AXIS. A TROUGH IS EMBEDDED IN THIS NE FLOW FROM 26N136W TO 
21N140 ACCORDING TO THE 1840 UTC ASCAT PASS. THIS IS THE SURFACE 
REFLECTION OF THE AFOREMENTIONED UPPER BROAD TROUGH TO THE W. 
THE STRENGTHENED PRESSURE GRADIENT BETWEEN THE RIDGE AND THIS 
SURFACE TROUGH IS SUPPORTING FRESH TO STRONG TRADES NEAR THE 
TROUGH. THE TROUGH AND THE WINDS WILL SLOWLY MOVE W OF THE AREA 
BY SUN...AND THE SUBTROPICAL RIDGE WILL BE OVERTAKEN BY HIGH 
PRES W OF THE COLD FRONT N OF THE AREA. THE RIDGING IS EXPECTED 
TO REMAIN WEAK...AND TRADE WINDS WILL DIMINISH BELOW A STRONG 
BREEZE OVER THE ENTIRE AREA W OF 120W ON SUN.

$$
SCHAUER