000
AXPZ20 KNHC 120225
TWDEP 

TROPICAL WEATHER DISCUSSION                                     
NWS NATIONAL HURRICANE CENTER MIAMI FL                         
0405 UTC TUE MAY 12 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY  
THROUGH 0215 UTC. 
 
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
          
SCATTEROMETER WINDS INDICATE THAT THE ITCZ FORMS NEAR 06N91W AND 
EXTENDS W TO AN EMBEDDED TROUGH AT 06N135W AND CONTINUES SW TO 
BEYOND 04N140W. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS 
NOTED S OF THE ITCZ WITHIN 60 NM OF 05N92W AND WITHIN THE ENTIRE 
AREA FROM 02-10N BETWEEN 115-135W.
 
A 1007 MB SURFACE LOW IS OVER COLOMBIA AT 10N75W WITH A TROUGH 
EXTENDING SW TO A BASE OVER THE E PACIFIC NEAR 07N81W. SCATTERED 
MODERATE CONVECTION IS NOTED WITHIN 60 NM OF 03N84.5W.

...DISCUSSION...

AN UPPER TROUGH EXTENDS INTO THE DISCUSSION AREA FROM 32N127W TO 
22N128W. AN UPPER ANTICYCLONE IS CENTERED OVER THE TROPICS AT 
11N109W WITH AN UPPER RIDGE EXTENDING W TO BEYOND 10N140W...AND 
ENHANCING CONVECTION ALONG THE ITCZ BETWEEN 110-140W AS 
PREVIOUSLY DESCRIBED. AN UPPER RIDGE ALSO EXTENDS NE FROM THE 
ANTICYCLONE ACROSS MEXICO TO A CREST OVER THE NE GULF OF 
MEXICO. ITCZ DEBRIS MOISTURE IS ADVECTED N AND MERGES WITH A 
DENSE TROPICAL PLUME ORIGINATING IN THE CENTRAL PACIFIC...ALL 
CONCENTRATING INTO A PLUME THAT CONTINUES NE WITHIN 420 NM OF A 
LINE FROM 15N124W TO ACROSS NORTHERN MEXICO AND FEEDS INTO 
CONVECTION OVER THE SE CONUS. 

AN UPPER TROUGH EXTENDS S ACROSS THE WESTERN CARIBBEAN FROM 
CENTRAL CUBA TO ACROSS COSTA RICA TO A BASE OVER THE DEEP 
TROPICAL PACIFIC AT 07N86W. DIFFLUENCE E OF THIS TROUGH IS 
ENHANCING CONVECTION ALONG A SURFACE TROUGH EXTENDING SW OFF THE 
COLOMBIAN COAST. THE DEBRIS MOISTURE IS ADVECTED NE ACROSS THE 
CENTRAL CARIBBEAN.
 
ELSEWHERE AT THE LOW LEVELS A SURFACE RIDGE EXTENDS FROM 
32N140WS TO 15N106W. THE GRADIENT SW OF THE RIDGE IS SUPPORTING 
15-20 KT NE TRADES ACROSS THE WATERS FROM 07-12N BETWEEN 120-
140W. THE ASSOCIATED NE SWELL IS MIXING SEVERAL OTHER LONG 
PERIOD SWELLS RESULTING IN COMBINED SEAS OF 8-11 FT ACROSS THE 
WATERS FROM 05-19N W OF 115W. THE ENHANCED SEAS WILL GRADUALLY 
SUBSIDE TO 6-9 FT ON TUE. GUIDANCE IS SUGGESTING THAT A COUPLE 
OF SURFACE LOWS WILL FORM ALONG THE ITCZ NEAR 11N131W AND 
08N137W LATE TUE WITH 20-25 KT CONDITIONS DEVELOPING NEAR THE 
LOWS ON WED.  
  
LONG PERIOD SOUTHERLY SWELL AT 16-20 SECONDS IS OBSERVED ACROSS  
THE TROPICS S OF 05N BETWEEN 85-120W WITH COMBINED SEAS OF 7-10 
FT. THESE SOUTHERLY SWELLS WILL SPREAD N REACHING THE PACIFIC 
COAST OF MEXICO AND CENTRAL AMERICA ON TUE AND WED WITH SEAS OF 
5-7 FT.
 
GULF OF PAPAGAYO...GUIDANCE INDICATES NE-E 20-25 KT WINDS WILL 
DEVELOP OVER AND JUST SW OF THE GULF OF PAPAGAYO LATE EACH NIGHT 
THROUGH THE EARLY MORNING HOURS...THEN DIMINISH TO 15-20 KT 
DURING THE AFTERNOONS AND EVENINGS. SEAS ARE EXPECTED TO BUILD 
TO 9 FT WITH THE RESULTANT NE SWELL PROPAGATING SW AND MIXING 
WITH LONG PERIOD CROSS-EQUATORIAL SWELL ACROSS THE PACIFIC 
WATERS FROM 07-12N BETWEEN 86W AND 100W. 

GULF OF TEHUANTEPEC...A 20-25 KT NORTHERLY SURGE IS EXPECTED 
LATE TUE NIGHT THROUGH SUNRISE ON WED...WITH SEAS BUILDING TO 8 
FT.

.GULF OF CALIFORNIA...SOUTHERLY 20-25 KT WINDS EXPECTED ACROSS 
THE WATERS N OF 30N ON TUE EVENING THROUGH LATE TUE NIGHT...WITH 
SEAS TO 6 FT. 

$$ 
NELSON