000
AXPZ20 KNHC 182132
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC MON NOV 18 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2100 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...           
THE MONSOON TROUGH IS ALONG 08N78W TO 09N84W TO 09N89W TO 
08N100W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 
08N100W TO 07N113W TO 06N120W TO 10N131W. SCATTERED MODERATE 
CONVECTION IS FROM 03N TO 09N BETWEEN 77W AND 85W. ISOLATED 
MODERATE CONVECTION IS FROM 06N TO 12N BETWEEN 89W AND 97W...AND 
FROM 07N TO 09N BETWEEN 113W AND 119W.

...DISCUSSION...                                               
AN UPPER LEVEL TROUGH AXIS EXTENDS FROM SOUTHERN CALIFORNIA NEAR 
34N118W INTO A MIDDLE TO UPPER LEVEL LOW CENTERED NEAR 17N137W. 
WHILE THIS UPPER LEVEL FEATURE LACKS ANY SIGNIFICANT SURFACE 
FRONT OVER THE NORTHERN WATERS...THE UPPER LEVEL LOW TO THE SW 
SUPPORTS A SURFACE TROUGH AXIS ANALYZED FROM 17N125W TO 12N139W 
WITH SOUTHWESTERLY FLOW ALOFT AND LOW-LEVEL MOISTURE CONVERGENCE 
GENERATING ISOLATED MODERATE CONVECTION GENERALLY WITHIN 120 NM 
EITHER SIDE OF THE AXIS. SOUTHWESTERLY FLOW DOMINATE THE 
REMAINDER OF THE DISCUSSION AREA W OF 101W BETWEEN THE UPPER 
LEVEL LOW AND AN UPPER LEVEL ANTICYCLONE CENTERED NEAR 03N115W. 
WATER VAPOR IMAGERY INDICATES THAT MOST OF THIS SW FLOW ALOFT 
REMAINS RELATIVELY DRY AND STABLE WITH THE EXCEPTION OF CLOSE 
PROXIMITY TO THE THE AFOREMENTIONED SURFACE TROUGH. 
OTHERWISE...TO THE NORTHWEST OF THE UPPER LEVEL TROUGH AXIS A 
RIDGE AXIS EXTENDS FROM NE OF THE HAWAIIAN ISLANDS NEAR 22N149W 
TO BEYOND 32N133W. MOSTLY HIGH LEVEL CLOUDINESS IS NOTED N OF 
27N W OF 123W AHEAD OF AN APPROACHING COLD FRONT TO THE NW OF 
THE AREA.

OVER THE EASTERN WATERS E OF 100W...AN UPPER LEVEL ANTICYCLONIC 
CIRCULATION IS CENTERED OVER NORTHERN GUATEMALA NEAR 18N90W AND 
IS PROVIDING MUCH OF THE AREA S OF 12N E OF 100W WITH A 
FAVORABLE UPPER LEVEL DIFFLUENT ENVIRONMENT. GIVEN THE CLOSE 
PROXIMITY TO THE MONSOON TROUGH AXIS AND AMPLE UPPER LEVEL 
LIFTING DYNAMICS...SCATTERED SHOWERS AND TSTMS ARE OCCURRING 
SOUTH OF PANAMA AND COSTA RICA AND ACROSS AN AREA TO THE WEST 
FROM 06N TO 12N BETWEEN 89W AND 97W.

AT THE SURFACE...A 1022 MB HIGH IS CENTERED NEAR 31N124W WITH A 
RIDGE AXIS EXTENDING SE TO NEAR 18N110W. WITH A RELATIVELY 
RELAXED PRESSURE GRADIENT IN PLACE N-NE TRADES AROUND THE HIGH 
ARE REMAINING GENERALLY 15 KT OR LESS AT THIS TIME WITH SEAS 
RANGING FROM 4 TO 6 FT. THE HIGH IS FORECAST TO MOVE SW OVER THE 
NEXT 24 TO 48 HOURS AS THE PREVIOUSLY MENTIONED COLD FRONT TO 
THE NW OF THE AREA SLIDES EASTWARD ALONG THE NORTHERN BOUNDARY 
OF 32N. AS THIS OCCURS LATE TUESDAY INTO EARLY WEDNESDAY THE 
PRESSURE GRADIENT ALONG THE BAJA CALIFORNIA COAST WILL 
STRENGTHEN SOMEWHAT WITH N-NW WINDS REACHING 20 KT AND SEAS 
BUILDING TO A RANGE OF 5 TO 7 FT.

$$
HUFFMAN