000
AXPZ20 KNHC 200913
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC WED FEB 20 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 
0900 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...

THE MONSOON TROUGH IS ALONG 03N78W TO 01N84W. THE INTERTROPICAL 
CONVERGENCE ZONE AXIS EXTENDS FROM 01N84W TO 05N110W TO 06N125W 
TO 06N140W. SCATTERED MODERATE CONVECTION IS FROM 05N TO 12N 
BETWEEN 127W AND 133W.

...DISCUSSION...

AN UPPER LEVEL DISTURBANCE IS MOVING SE ACROSS SOUTHERN 
CALIFORNIA...SUPPORTING THE APPROACH OF A COLD FRONT CURRENTLY 
EXTENDING FROM SOUTHERN CALIFORNIA TO 30N123W TO 31N129W. THE 
FRONT WILL CLEAR SOUTHERN CALIFORNIA AND THE NORTHERN PORTIONS 
OF BAJA AND THE GULF OF CALIFORNIA BY LATE TODAY...FOLLOWED BY 
STRONG TO NEAR GALE FORCE NW WINDS OVER THE PACIFIC WATERS N OF 
27N E OF 130W AND SEAS BUILDING TO 10 TO 14 FT IN NW SWELL. 
FRESH TO STRONG SW TO W WINDS WILL PRECEDE THE FRONT OVER THE 
NORTHERN PORTION OF THE GULF OF CALIFORNIA N OF 29N. 

THE SUPPORTING UPPER DYNAMICS WILL LIFT NE TONIGHT LEAVING THE 
FRONT TO STALL AND WEAKEN OVER NORTHERN BAJA AND THE NORTHERN 
GULF OF CALIFORNIA. WINDS WILL DIMINISH ACROSS THE REGION 
ACCORDINGLY...ALTHOUGH ANOTHER UPPER DISTURBANCE WILL FOLLOW THE 
FIRST ON THU AND MAINTAIN FRESH NORTHERLY FLOW OFF NORTHERN BAJA 
INTO FRI. 

FARTHER WEST...1034 MB HIGH PRES CENTERED N OF HAWAII NEAR 
35N145W WILL CHANGE LITTLE THROUGH THE END OF THE WEEK...AND 
MAINTAIN FRESH TO STRONG TRADE WINDS ACROSS THE AREA GENERALLY N 
OF 08N W OF 120W THROUGH AT LEAST SAT. 

MOIST AND DIVERGENT MID/UPPER LEVEL SW FLOW ASSOCIATED WITH AN 
UPPER LOW ABOUT 450 NM NE OF THE BIG ISLAND OF HAWAII IS 
MAINTAINING AREAS OF UNSETTLED WEATHER W OF 130W...INCLUDING AN 
AREA OF SCATTERED MODERATE CONVECTION ALONG THE ITCZ BETWEEN 
125W AND 130W.

GAP WINDS...
FRESH TO STRONG WINDS WILL CONTINUE TO PULSE IN THE GULF OF 
PAPAGAYO...WITH THE STRONGEST WINDS OCCURRING DURING THE 
OVERNIGHT AND EARLY MORNING HOURS WITH ENHANCEMENT BY NOCTURNAL 
DRAINAGE FLOW. ASSOCIATED SIGNIFICANT WAVE HEIGHTS WILL PEAK 
AROUND 9 FT. A LONG PLUME OF MODERATE TO FRESH EASTERLY WINDS 
ALONG WITH SEAS OF UP TO 8 FT IN MIXED NE AND NW SWELL WILL 
PERSIST WELL DOWNWIND OF PAPAGAYO FROM 05N TO 11N BETWEEN 97W 
AND 115W THROUGH THIS MORNING.

HIGH PRES OVER EASTERN MEXICO AND LOWERING PRES S OF THE GULF OF 
TEHUANTEPEC WILL PRODUCE ENOUGH OF A PRES GRADIENT ACROSS THE 
ISTHMUS OF TEHUANTEPEC TO SUPPORT A BRIEF PULSE OF 20 TO 30 KT 
GAP WINDS THROUGH THIS MORNING.

$$
CHRISTENSEN