000
AXPZ20 KNHC 230233
TWDEP 

TROPICAL WEATHER DISCUSSION                                     
NWS NATIONAL HURRICANE CENTER MIAMI FL                         
0405 UTC WED SEP 23 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 
0230 UTC.               

...TROPICAL WAVES... 

A TROPICAL WAVE IS ANALYZED FROM 05-16N BETWEEN 94-96W WITH 
SCATTERED MODERATE ISOLATED STRONG CONVECTION FLARING WITHIN 270 
NM OF WAVE AXIS. 

A TROPICAL WAVE WAS ANALYZED FROM 07N121W TO 16N118W AND HAS 
BEEN MOVING W AT ABOUT 12 KT. SCATTERED MODERATE ISOLATED STRONG 
CONVECTION IS NOTED WITHIN THE AREA BOUNDED BY 03-15N BETWEEN 
116-124W.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...            

THE MONSOON TROUGH AXIS EXTENDS W FROM THE CARIBBEAN COAST OF  
COLOMBIA AT 09N77W TO ACROSS THE PANAMA TO THE 
PACIFIC COAST OF COSTA RICA AT 09N84W...CONTINUES W TO THE 
TROPICAL WAVE AT 10N93W TO 09N105W...THEN TURNS SLIGHTLY NW TO 
12N112W WHERE IT LOSES IDENTITY. EXCEPT AS PREVIOUSLY DESCRIBED 
IN ASSOCIATION WITH THE TWO TROPICAL WAVES...SCATTERED MODERATE 
ISOLATED STRONG CONVECTION IS OBSERVED FROM 04-11N E OF 90W TO 
THE COAST OF COLOMBIA. SIMILAR CONVECTION IS NOTED WITHIN 75 NM 
OF 08N107W AND 18N121W...AND DECAYING WITHIN 150 NM OF 11N139W.

...DISCUSSION...

A WEAK SURFACE RIDGE EXTENDS FROM 32N135W TO 15N110W WITH A WEAK 
TROUGH FILLING JUST N OF THE RIDGE AXIS BETWEEN 120-125W...
AND SURROUNDED BY LIGHT AND VARIABLE WINDS. LIGHT TO GENTLE 
ANTICYCLONIC FLOW IS OBSERVED ELSEWHERE ACROSS THE DISCUSSION 
AREA TO THE N OF 17N AND W OF 115W. THE TROUGH WILL GRADUALLY 
DISSIPATE THROUGH WED WITH THE RIDGE AXIS FORECAST TO EXTENDS SE
FROM 32N130W TO NEAR 15N110W ON THU.
 
THE PRESSURE GRADIENT WELL E OF THE RIDGE IS SUPPORTING MODERATE 
NW FLOW ACROSS THE PACIFIC WATERS FROM 21-27N BETWEEN 105-115W 
TO INCLUDE THE GULF OF CALIFORNIA TO THE S OF 27N. EXPECT LITTLE 
CHANGE TILL THE GRADIENT RELAXES ON FRI.  

MODERATE TO FRESH NE TRADES ARE OBSERVED WELL S OF THE RIDGE 
ACROSS THE TROPICAL WATERS FROM 14-18N W OF 130W WHERE THE 
CONVECTION IS CURRENTLY DECAYING AS PREVIOUSLY MENTIONED...BUT 
MAY REGENERATE AS CONDITIONS ARE FAVORABLE UNDER AN UPPER RIDGE.

GAP WINDS...THE PRESSURE GRADIENT BETWEEN WEAK RIDGING IN THE  
GULF OF MEXICO...AND THE TROPICAL WAVE PASSING W THROUGH THE 
PACIFIC WATERS TO THE S OF THE GULF OF TEHUANTEPEC...IS DRIVING 
PULSES OF STRONG NORTHERLY WINDS THROUGH CHIVELA PASS. LITTLE 
CHANGE EXPECTED THROUGH EARLY SUN MORNING WITH THE STRONGEST 
WINDS EXPECTED DURING MAXIMUM DRAINAGE AROUND SUNRISE EACH 
MORNING.  

NORTHERLY SWELL IS MIXING WITH CROSS EQUATORIAL SE AND SW SWELL 
ACROSS THE DEEP TROPICS GENERALLY S OF 06N BETWEEN 93-128W 
RESULTING IN COMBINED SEAS OF 7-9 FT. EXPECT THESE SEAS TO 
SUBSIDE THROUGH WED...THEN BUILD AGAIN IN RE-ENFORCING SOUTHERLY 
SWELL ON THU-FRI.
    
$$
NELSON