000
AXPZ20 KNHC 110930
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC MON FEB 11 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0645 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
THE MONSOON TROUGH AXIS WAS ANALYZED FROM 02N80W TO 05N94W TO 
04N100W. ITCZ AXIS WAS ANALYZED FROM 04N100W TO 04N110W TO 
08N117W TO 06N124W TO 06N128W THEN CONTINUES FROM 06N132W TO 
04N140W. A TROUGH LIES ALONG 130W FROM 03N TO 10N. THERE IS NO 
SIGNIFICANT DEEP CONVECTION NOTED OVER THE FORECAST AREA. 

...DISCUSSION...
A 120-140 KT WESTERLY UPPER JET IN PLACE FROM 20N140W TO NW 
MEXICO WILL REMAIN STATIONARY OVER THE NEXT FEW DAYS. AN UPPER 
LOW NEAR 28N126W EVIDENT ON WATER VAPOR IMAGERY LIES IN THE 
WESTERN SIDE OF A MEAN UPPER TROUGH CENTERED OVER THE INTERIOR 
WESTERN UNITED STATES. THIS ENERGY WILL BECOME ELONGATED JUST N 
OF THE JET AXIS TODAY AND SLOWLY MAKE ITS WAY INTO NW MEXICO 
OVERNIGHT TUE NIGHT AS A NEW SHORTWAVE SYSTEM ON THE BACKSIDE OF 
THE MEAN TROUGH APPROACHES NE FORECAST WATERS FROM THE N. AS THE 
REMNANTS OF THE UPPER LOW MOVES INLAND TUE NIGHT...SURFACE 
TROUGHING ALONG THE BAJA PENINSULA WILL MOVE INLAND AND THE 
SUBTROPICAL RIDGE WILL SHIFT EASTWARD. THIS WILL INCREASE THE 
PRESSURE GRADIENT OVER THE GULF OF CALIFORNIA. FRESH TO STRONG 
N-NW WINDS ARE FORECAST TO OVERTAKE THE GULF OVERNIGHT TUE NIGHT 
AS A RESULT. 

AN UPPER LOW LIES NEAR 34N145W AND REFLECTS A 1020 MB LOW AT THE 
SURFACE NEAR 36N143W WITH A STATIONARY FRONT EXTENDING FROM THE 
LOW THROUGH 32N141W TO 25N147W. NW SWELL FROM THIS SYSTEM...WITH 
PERIODS IN THE 19-21 SECOND RANGE...HAS MOVED THROUGH NW WATERS 
AND THE BAJA CALIFORNIA NORTE COAST. THE LEADING EDGE OF THE 
SWELL WILL REACH MANZANILLO MEXICO BY TUE MORNING AND LIE ALONG 
97W S OF 13N BY WED MORNING. SEAS AS HIGH AS 12 FT LIE OVER NW 
WATERS AT THE MOMENT. THE 0548 UTC ASCAT PASS SHOWS WINDS N OF 
31N AND W OF 138W ARE A FRESH TO STRONG SE BREEZE. THESE WINDS 
WILL MOVE S OF 30N TODAY. THE FRONT WILL MOVE SOUTHWARD AND 
GRADUALLY DISSIPATE THROUGH THE FORECAST PERIOD...BUT THE 
PRESSURE GRADIENT BETWEEN THE LINGERING TROUGHING AND THE 
SUBTROPICAL RIDGE WILL KEEP FRESH TO STRONG WINDS OVER THE NE 
CORNER OF THE FORECAST AREA INTO WED MORNING. SOME SCATTERED 
SHOWERS AND POSSIBLY AN ISOLATED THUNDERSTORM ARE CURRENTLY NEAR 
THE FRONT N OF 30N AND WILL HUG NW WATERS THROUGH WED MORNING. 

THE 0544 UTC ASCAT PASS SHOWS MODERATE TO FRESH TRADE WINDS LIE 
OVER WESTERN WATERS N OF THE ITCZ. AS THE SUBTROPICAL RIDGE 
BECOMES SQUISHED BETWEEN THE AFOREMENTIONED TROUGHING OVER THE 
BAJA PENINSULA AND TROUGHING OVER NW WATERS...THE PRESSURE 
GRADIENT WILL INCREASE N OF THE ITCZ OVER CENTRAL WATERS. LOOK 
FOR TRADES TO INCREASE TO A FRESH TO STRONG BREEZE GENERALLY 
BETWEEN 120W AND 135W OVERNIGHT TUE NIGHT.

GAP WINDS...
GULF OF PAPAGAYO...THE INCREASED PRESSURE GRADIENT BETWEEN THE 
MONSOON TROUGH TO THE S AND RIDGING OVER THE NW CARIBBEAN HAS 
INCREASED THE NE TRADE WIND FLOW THROUGH CENTRAL AMERICA TO A 
FRESH TO STRONG BREEZE IN THE GULF OF PAPAGAYO. THESE WINDS WILL 
CONTINUE TO PULSE TO 25 KT THROUGH EARLY TUE...WITH THE 
STRONGEST WINDS EXPECTED IN THE EARLY MORNING HOURS WHEN 
DRAINAGE FLOW OFF THE LAND IS AT A MAXIMUM. SEAS WILL BRIEFLY 
BUILD TO AS MUCH AS 8 FT IN THE STRONGEST WINDS. RIDGING IN THE 
CARIBBEAN WILL WEAKEN TUE...SLACKENING THE PRESSURE GRADIENT AND 
DIMINISHING WINDS THROUGH CENTRAL AMERICA. 

$$
SCHAUER