000
AXPZ20 KNHC 190945
TWDEP 

TROPICAL WEATHER DISCUSSION                                     
NWS NATIONAL HURRICANE CENTER MIAMI FL                         
1005 UTC FRI DEC 18 2015 

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
0945 UTC.               
 
...SPECIAL FEATURE...

GULF OF TEHUANTEPEC...N-NE 40-50 KT STORM FORCE WINDS CONTINUE
WITHIN 45 NM OF LINE FROM 16N95W TO 15N95W TO 13N96W...WITH 15-
22 FT SEAS...HIGHEST SEAS NEAR 14N95.5W. A LARGE AREA OF STRONG
GALE 30-40 KT WINDS SURROUND THE STORM AREA WITHIN 75 NM OF LINE
FROM 16N95W TO 15N95W TO 11.5N98.5W WITH 10-15 FT SEAS. EXPECT
THESE NORTHERLY WINDS TO DIMINISH BELOW STORM FORCE LATER THIS
MORNING AND DIMINISH BELOW GALE FORCE LATE SUN. HOWEVER...THE
RESULTANT N-NE SWELL IS MIXING WITH WITH CROSS EQUATORIAL
SOUTHERLY SWELL...AND LONG PERIOD NW SWELL...DRIVING COMBINED
SEAS HEIGHTS TO 8-12 FT ACROSS THE WATERS FROM THE EQUATOR TO
13N BETWEEN 90-115W BY SUN EVENING. EXPECT THE NORTHERLY WINDS
TO DIMINISH TO 15-20 KT ON MON NIGHT...WITH LIGHT NOCTURNAL WINDS
THEN EXPECTED THROUGH THU EVENING.
   
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...            

A SURFACE TROUGH EXTENDS SW OFF THE COAST OF COLOMBIA AT 05N77W
TO 05N90W WHERE SCATTEROMETER WINDS INDICATE THAT AN ITCZ FORMS
AND THEN CONTINUES W TO AN EMBEDDED TROUGH AT 05N126W...WITH THE
ITCZ THEN RESUMING FROM 05N126W TO BEYOND 02N140W. THE EMBEDDED
TROUGH EXTENDS S-N FROM 01N126W TO 10N126W. SCATTERED MODERATE
ISOLATED STRONG CONVECTION IS OBSERVED WITHIN 180 NM OF
04.5N81W...WITHIN 210 NM OF 04N91W...AND WITHIN 180 NM EITHER
SIDE OF LINES FROM 07N111W TO 08N125W AND FROM 06N130W TO
02N140W.  

...DISCUSSION...

A COLD FRONT EXTENDING FROM 32N124W TO 26N140W WITH CONTINUE E
WHILE WEAKENING WITH THE NORTHERN PORTION OF THE FRONT REACHING
THE NORTHERN BAJA CALIFORNIA PENINSULA ON SUN. ALTHOUGH ONLY A
15-20 KT SW-W-NW-N WIND SHIFT IS NOTED WITH THE FRONTAL
PASSAGE...A BATCH OF LARGE LONG PERIOD NW SWELL WILL FOLLOW THE
FRONT WITH MAX SEAS OF 14 FT REACHING ALONG 32N BETWEEN 130-140W
TODAY. EXPECT THESE SEAS TO SUBSIDE WITH 8-10 FT CONDITIONS
REACHING THE PACIFIC COAST OF BAJA ON SUN NIGHT. POST FRONTAL
HIGH PRESSURE WILL TIGHTEN THE GRADIENT ACROSS THE TROPICS N OF
THE ITCZ WITH NE TRADES DEVELOPING TONIGHT W OF 115W WITH
COMBINED SEAS GRADUALLY BUILDING TO 8-12 FT BY LATE MON. THE
GRADIENT WILL ALSO TIGHTEN NE OF THE POST-FRONTAL RIDGE ON SUN
NIGHT WITH 20 KT NW WINDS SPREADING S ACROSS THE SUBTROPICAL
WATERS N OF 28N E OF 122W TO THE PACIFIC COAST OF BAJA BY MON
NIGHT. THE GRADIENT WILL CONTINUE TO TIGHTEN ON TUE WITH STRONG
TO NEAR GALE FORCE NW WINDS FORECAST FROM 28-32N E OF 122W ON
TUE NIGHT AND WED...WITH SEAS BUILDING TO AS HIGH AS 15 FT ALONG
32N. 
 
GULF OF PAPAGAYO...NE 20-25 KT DRAINAGE WINDS ARE OBSERVED
ACROSS THE GULF OF PAPAGAYO AND EXTEND DOWNSTREAM TO NEAR 09N90W.
EXPECT THESE WINDS TO DIMINISH BRIEFLY LATE TODAY...THEN QUICKLY
INCREASE TO 20-30 KT TONIGHT AND CONTINUE THROUGH SUN MORNING.
EXPECT 20-25 KT CONDITIONS ON SUN AND MON NIGHTS.
 
$$
NELSON