000
AXPZ20 KNHC 210234
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL                         
0405 UTC FRI AUG 21 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 
0200 UTC.               

...TROPICAL WAVES...

A TROPICAL WAVE IS ALONG 103W FROM 06N TO 14N. SCATTERED 
MODERATE ISOLATED STRONG CONVECTION IS FROM 07N TO 10N BETWEEN 
100W AND 104W. THIS WAVE IS SITUATED NOT FAR FROM ANOTHER 
TROPICAL WAVE THAT IS NOW ESTIMATED TO BE ALONG 108W. THESE 
TROPICAL WAVES COULD MERGE AT SOME POINT. LATEST SATELLITE 
IMAGERY AND THE EDGE OF AN EARLIER ASCAT PASS SUGGEST THAT A 
BROAD AREA OF LOW PRES IS TRYING TO DEVELOP BETWEEN THESE TWO 
FEATURES. THE GFS GLOBAL MODEL ALSO INDICATES THE PRESENCE OF A 
BROAD LOW PRES AREA NEAR 10N109W IN ABOUT 24 HOURS.

A TROPICAL WAVE IS ALONG 108W FROM 05N TO 12N. SCATTERED 
MODERATE ISOLATED STRONG CONVECTION IS FROM 05N TO 10N BETWEEN 
106W AND 111W. THIS WAVE SHOWS UP VERY WELL ON THE TPW PRODUCT 
WHERE A HIGH AMPLITUDE NORTHWARD BULGE OF MOISTURE IS OBSERVED. 
ALSO...THE WAVE IS DEPICTED IN THE LATEST GFS 700 MB STREAMLINE 
AND 850 MB VORTICITY ANALYSIS.  

A TROPICAL WAVE AXIS IS ALONG 124W FROM 10N TO 16N. SCATTERED 
MODERATE CONVECTION IS SEEN FROM 10N TO 15N BETWEEN 120W AND 
128W. THE WAVE REMAINS BROADLY APPARENT ON THE LATEST GFS 700 MB 
STREAMLINE AND 850 MB VORTICITY ANALYSIS. THE TPW IMAGERY SHOWS 
A LARGE SWATH OF DEEP TROPICAL MOISTURE IN ASSOCIATION WITH THIS 
SYSTEM. 

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

CURRENTLY THERE IS NOT A WELL DEFINED MONSOON TROUGH OR ITCZ. 
MOST OF THE CONVECTIVE ACTIVITY IS ASSOCIATED WITH THE TROPICAL 
WAVES MENTIONED ABOVE. 

A TROUGH IS ANALYZED ON THE 0000 UTC MAP FROM 07N77W TO 06N88W. 
SCATTERED MODERATE ISOLATED STRONG CONVECTION IS NOTED FROM 03N 
TO 07N E OF 88W TO THE COAST OF COLOMBIA.
 
...DISCUSSION... 

SHIP OBSERVATIONS AND DATA FROM AN EARLIER ASCAT PASS INDICATE 
MODERATE TO FRESH NW WINDS OFF THE PACIFIC COAST OF THE BAJA 
PENINSULA...BETWEEN 1016 MB HIGH PRES CENTERED NEAR 27N128W AND 
A SURFACE TROUGH ALONG THE BAJA CALIFORNIA PENINSULA. MODERATE 
TO FRESH SOUTHERLY WINDS ARE ALSO NOTED OVER THE NORTHERN GULF 
OF CALIFORNIA WITH SEAS TO 4 FT. THE HIGH IS FORECAST TO REMAIN 
NEARLY STATIONARY OVER THE NEXT 24 HOURS.

THE REMNANT LOW OF T.D. ELEVEN PERSISTS NEAR 30N133W WITH A 
CENTRAL PRES OF 1014 MB. A SURFACE TROUGH EXTENDS FROM THE LOW 
CENTER TO NEAR 28N137W. NO SIGNIFICANT CONVECTION OR WINDS ARE 
NOTED WITH THIS FEATURE AND SEAS HAVE SUBSIDED BELOW 8 FT. THE 
LOW PRES IS EXPECTED TO WEAKEN AND NOT MOVE MUCH THROUGH THE 
NEXT 2 TO 3 DAYS. FARTHER SOUTH...ANOTHER TROUGH IS ANALYZED 
FROM 19N134W TO 15N140W. THIS TROUGH WAS PREVIOUSLY CONNECTED TO 
T.D. THREE-C LOCATED WEST OF AREA. 

FRESH TO LOCALLY STRONG GAP WINDS ARE EXPECTED LATE TONIGHT INTO 
FRI MORNING ACROSS THE GULF OF PAPAGAYO WITH BUILDING SEAS OF 6-
7 FT DOWNSTREAM FROM GULF TO NEAR 90W.   
 
$$ 
GR