000
AXPZ20 KNHC 072151
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC THU FEB 07 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...
MONSOON TROUGH 03N78W TO 07N85W TO 04N92W TO 08N103W TO 07N109W 
THEN ITCZ TO 05N140W.  ISOLATED MODERATE CONVECTION WITHIN 90 NM 
OF AXIS FROM 113W TO 117W.

...DISCUSSION...
WEAK BUT SHARP UPPER LEVEL TROUGH FROM 21N108W TO 00N113W MOVE E 
WITH A SMALL AMOUNT OF TROPICAL MOISTURE ADVECTED NE HEADED FOR 
SOUTHERN MEXICO.  TWO BROAD ANTICYCLONES..ON EACH SIDE OF TROUGH 
...MAINTAIN VERY DRY AND STABLE CONDITIONS OVER REMAINDER OF 
BASIN.  ONLY ISOLATED CONVECTION NOTED WITHIN 90 NM OF ITCZ AXIS 
FROM 113W TO 117W.  MODEL GUIDANCE INDICATES TROUGH MOVES OUT OF 
BASIN SAT...ALLOWING LONGWAVE TROUGH WELL N OF AREA TO FLATTEN 
CREST OF RIDGE LEAVING A FLAT ZONAL UPPER CONDITIONS N OF 20N 
THROUGH REMAINDER OF FORECAST PERIOD.

...AT THE LOWER LEVELS...
HEALTHY HIGH PRES CENTER 1033 MB AT 37N143W WITH ASSOCIATED 
RIDGE EXTENDING SE TO 18N113W PROMPTS MODERATE TO FRESH TRADES 
WITH SEAS 10 TO 112 FT FROM 09N TO 23N W OF 130W TODAY AND FRI.  
HIGH PRES DRIFTS E BY SAT DIMINISHING WINDS OVER W SIDE OF BASIN 
BUT INCREASING THEM ALONG SOUTHERN CALIFORNIA COAST WITH SWELLS 
ENCROACHING INTO E PAC N OF 26N E OF 130W BUILDING TO 12-13 FT.  

HIGH PRES CENTER MOVE E THROUGH SAT...HOWEVER PRES GRADIENT 
REMAINS WEAK AND WINDS AREA EXPECTED TO INCREASE WINDS TO 
ADVISORY CRITERIA.  NW SWELLS CONTINUE TO SPREAD S AND E OVER 
NEXT COUPLE OF DAYS WHILE SLOWLY SUBSIDING.  NEW SET OF NW 
SWELLS ENTER INTO NE PART OF FORECAST AREA WITH COMBINED SEAS 
8-12 FT N OF 24N FROM 114W TO 132W EARLY SAT.

STRONG CARIBBEAN TRADES LATE IN THE FORECAST PERIOD SEEP THROUGH 
GAPS IN NICARAGUA MOUNTAINS AND PROMPT INCREASING FRESH BREEZE 
BUT SEAS BELOW 8 FT OVER GULF OF PAPAGAYO IN E PAC.  WINDS AND 
SEAS CONTINUE TO INCREASE BEYOND FORECAST PERIOD.   
 
$$
WALLY BARNES