000
AXPZ20 KNHC 050933
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC SUN AUG 05 2012

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 
0900 UTC.

...TROPICAL WAVES...
A TROPICAL WAVE EXTENDS FROM 15N102W TO A 1011 MB LOW PRES NEAR 
10.5N106W. THE CONVECTIVE ACTIVITY ASSOCIATED WITH THIS SYSTEM 
HAS DIMINISHED OVERNIGHT AND CURRENTLY SCATTERED SHOWERS AND 
ISOLATED TSTMS ARE WITHIN AROUND 30 NM EITHER SIDE OF WAVE AXIS. 
DEVELOPMENT...IF ANY...OF THIS SYSTEM IS EXPECTED TO BE SLOW TO 
OCCUR AS IT MOVES WESTWARD NEAR 10 KT. THIS SYSTEM HAS A LOW 
CHANCE OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS.

A TROPICAL WAVE LIES ALONG 125W FROM 10N TO 19N WITH A WEAK 1013 
MB LOW PRES NEAR 14N125W. ISOLATED MODERATE CONVECTION CAN BE 
FOUND FROM 13N TO 16N BETWEEN 122W AND 125W. NE WINDS OF 15-20 
KT ARE W OF THE WAVE AXIS FROM 15N TO 18N PER THE 0616 UTC 
ASCAT PASS. THE LOW PRES IS EXPECTED TO GRADUALLY WEAKEN ALONG 
THE WAVE OVER THE NEXT DAY OR SO AS THE WAVE CONTINUES TO MOVE 
WWD. 

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
MONSOON TROUGH AXIS EXTENDS FROM 08N78W TO 10N87W TO 12N103W 
THEN CONTINUES FROM 11N109W TO 12N122W. ITCZ AXIS IS FROM 
10N128W TO BEYOND 08N140W. SCATTERED MODERATE ISOLATED STRONG 
CONVECTION IS NOTED FROM 04N TO 08N E OF 80W...WITHIN 90 NM S OF 
TROUGH BETWEEN 80W AND 85W AND WITHIN 60 NM N OF TROUGH BETWEEN 
86W AND 89W. SCATTERED MODERATE CONVECTION IS SEEN FROM 08N TO 
11N BETWEEN 108W AND 120W...FROM 07N TO 09N BETWEEN 126W AND 
130W AND FROM 08N TO 10N W OF 138W. 

...DISCUSSION...
THE 1029 MB SUBTROPICAL HIGH LOCATED NEAR 40N148W EXTENDS A 
RIDGE SE OVER THE FORECAST WATERS TO NEAR 18N135W. THIS SYSTEM 
IS EXPECTED TO MOVE SW AND SLIGHTLY WEAKEN. IN THE MEANTIME...A 
WEAK HIGH PRES CELL WILL DEVELOP NEAR 31N132W IN ABOUT 24 HOURS. 
THE PRES GRADIENT BETWEEN THE RIDGE AND LOWER PRES NEAR THE 
TROPICAL WAVE CURRENTLY ALONG 125W WILL MAINTAIN AN AREA OF 20 
KT NE WINDS AND SEAS TO 8 FT NEAR THE NORTHERN END OF THE WAVE 
AXIS AS PREVIOUSLY MENTIONED. THESE CONDITIONS ARE FORECAST TO 
EXPAND WWD IN ABOUT 48 HOURS COVERING FROM 12N TO 16N W OF 130W.

A CROSS-EQUATORIAL SOUTHERLY SWELL TRAIN HAS REACHED AS FAR N AS 
THE SE GULF OF CALIFORNIA AND THE PACIFIC COAST OF BAJA 
CALIFORNIA NORTE. THE LEADING EDGE OF THIS SWELL EVENT HAS 
PERIODS IN EXCESS OF 20 SECONDS. THIS SWELL CONTINUES TO IMPACT 
THE COASTLINE OVER THE ENTIRE FORECAST AREA BUT IS BEGINNING TO 
DIMINISH. SWELL HEIGHTS TO 9 FT CAN BE EXPECTED AS FAR N AS 10N 
W OF THE GALAPAGOS ISLANDS TODAY. SEAS WILL SUBSIDE CONSIDERABLY 
BY MON. 

GAP WINDS...NORTHERLY WINDS ARE EXPECTED TO BRIEFLY INCREASE TO 
20 TO 25 KT IN THE GULF OF TEHUANTEPEC BY EARLY MON MORNING AND 
WILL LIKELY PERSIST THROUGH TUE. THIS GAP WIND EVENT COULD BE 
ASSOCIATED WITH THE PRESENCE OF TROPICAL CYCLONE ERNESTO OVER 
THE WESTERN CARIBBEAN. 

$$
GR