000
AXPZ20 KNHC 192205
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC SAT JAN 19 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 
21450 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...MONSOON 
TROUGH EXTENDS FROM 09N75W TO 03N80W TO 06N87W TO 06N92W WHERE 
LOW LEVEL WINDS SUGGEST IT TRANSITIONS TO ITCZ TO 06N106W TO 
09N120W TO 08N133W TO 09N140W. SCATTERED MODERATE/ISOLATED
STRONG CONVECTION EXISTS FROM 06N TO 08N BETWEEN 102W-107W 
...AND ALSO WITHIN 120 NM N OF THE MONSOON TROUGH BETWEEN 107W 
-112W

...DISCUSSION...

A WEAK NEGATIVELY-TILTED MID/UPPER LEVEL TROUGH PERSISTS 
OFFSHORE OF THE W COAST OF N AMERICA TO A WEAK MIDDLE/UPPER 
LEVEL CYCLONE LIFTING NE NEAR 30N125W. MODEL GUIDANCE DRIFTS 
CYCLONE ALONG 30N INTO NRN BAJA CALIFORNIA WITH SCATTERED 
MODERATE CONVECTION MAINLY ACROSS EASTERN SEMICIRCLE THROUGH 
MON. NARROW SHORTWAVE RIDGES ARE FOUND ON EITHER SIDE OF 
TROUGH...BOTH N OF 25N. VERY ENERGETIC NEGATIVE TILT LONGWAVE 
UPPER LEVEL TROUGH W OF AREA EXTENDS SEWD TO NEAR 20N145W. A 
SERIES OF SHORTWAVES ROTATING THROUGH THE BASE AND LIFTING N 
ACROSS ITS E SIDE SUPPORT A SERIES OF ADVANCING COLD FRONTS JUST 
W OF AREA BETWEEN 141W AND 151W...ALONG 30N.

A STRONG DEEP LAYER CYCLONE ASSOCIATED WITH THIS LONG WAVE 
TROUGH IS FORECAST TO MOVE ACROSS THE NW PORTION OF THE AREA
LATE TONIGHT INTO EARLY SUN WITH A PRONOUNCED SURFACE LOW OF
AROUND 1003 MB MOVING INTO THE FAR WRN PORITON OF THE AREA
NEAR 26N140W BY EARLY SUN AFTERNOON. THE LOW IS FORECAST TO 
EXTEND AN OCCLUDED FRONT TO 29N138W TO 24N137W...THEN TRANSITION
TO A COLD FRONT TO 15N140W. BY EARLY MON AFTERNOON...THE LOW
IS FORECAST TO BE NEAR 25N137W AS 1003 MB WITH THE OCCLUDED FRONT
TO EXTEND TO 29N135W TO 26N133W...THEN AS COLD FRONT TO NEAR
21N140W. SE TO S WINDS WILL APPROACH 30 KT AND TO POSSIBLE 
GALE FORCE AHEAD OF THE FRONT N OF ABOUT 21N. SCATTERED
MODERATE CONVECTION IS EXPECTED ALONG AND WITHIN 240 NM E OF THE 
FRONT N OF ABOUT 24N.  

ELSEWHERE AT THE SURFACE...A TIGHT PRES GRADIENT ACROSS CENTRAL 
AND SRN MEXICO CONTINUES TO PRODUCE STRONG N TO NE WINDS THROUGH 
THE CHIVELA PASS...AND INTO THE GULF OF TEHUANTEPEC. THE STORM
FORCE CONDTIONS ARE SLOWLY SUBSIDEING TO GALE FORCE. THE GALE FORCE
WINDS WILL REMAIN IN A SHRINKING AREA INTO EARLY NEXT WEEK.

NE 20 TO 25 KT WINDS WILL CONTINUE THROUGH THE GULF OF PAPAGAYO 
AND GULF OF FONSECA THROUGH EARLY NEXT WEEK. N TO NE 20 TO 25 KT
WINDS THROUGH THE GULF OF PANAMA AND BETWEEN 79W AND 81W N OF 
05N WILL PERSIST THROUGH MON.

A VERY STRONG NW SWELL EVENT HAS MOVED THROUGH THE CENTRAL 
PACIFIC AND HAWAIIAN ISLANDS IN THE PAST FEW DAYS...AND IS NOW 
ENTERING NW PORTIONS OF THE AREA WATERS...WITH FORERUNNER NW 
SWELL OF 25-27 SECONDS NOW REACHING SOUTHERN CALIFORNIA AND N 
BAJA CALIFORNIA. THESE SWELLS WILL SPREAD QUICKLY SE INTO THE 
REGIONAL WATERS DURING THE NEXT 24 HOURS TO PRODUCE VERY STRONG 
AND POWERFUL SURF ALONG EXPOSED REEFS AND COASTLINES...AND 
GENERATE EXTREMELY DANGEROUS RIP CURRENTS AND WIDESPREAD BEACH 
EROSION.

$$
AGUIRRE