000
AXPZ20 KNHC 191544
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC THU JUL 19 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1430 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
THE MONSOON TROUGH AXIS EXTENDS FROM 07N78W TO 10N88W TO A 1009 
MB LOW PRES NEAR 08N95W TO 07N100W TO 11N115W TO ANOTHER 1009 MB 
LOW PRES NEAR 09N121W TO 06N126W. THE ITCZ AXIS IS FROM 06N126W 
TO 05N132W TO 07N140W. SCATTERED MODERATE TO STRONG CONVECTION 
CAN BE FOUND WITHIN 120 NM N OF TROUGH BETWEEN 87W AND 98W. 
SIMILAR CONVECTION IS ALSO NOTED FROM 09N TO 13N BETWEEN 114W 
AND 118W...AND FROM 07N TO 10N BETWEEN 118W AND 125W. A 
DIFFLUENT PATTERN ALOFT IN HELPING TO INDUCE THIS CONVECTIVE 
ACTIVITY. 

...DISCUSSION...
A 1035 MB SUBTROPICAL HIGH CENTERED WELL NW OF THE FORECAST AREA 
HAS A RIDGE AXIS EXTENDING SE TO NEAR 20N112W. THE REMNANT LOW 
OF FABIO...ANALYZED 1012 MB LOW PRES NEAR 27.5N119.5W ON THE 
1200 UTC SURFACE MAP...IS LOCATED JUST TO THE EAST OF THIS 
RIDGE. THE REMNANT LOW OF FABIO IS FORECAST TO DISSIPATE IN 
ABOUT 6-12 HOURS AS THE SURFACE RIDGE CONTINUES TO BUILD ACROSS 
THE N WATERS.

A PAIR OF 1009 MB LOW PRES SYSTEMS ARE EMBEDDED IN THE MONSOON 
TROUGH. THE EASTERNMOST IS NEAR 08N95W WHILE THE WESTERNMOST IS 
LOCATED NEAR 09N121W. PRES GRADIENT BETWEEN THE BUILDING RIDGE 
TO THE N AND LOWER PRES ALONG THE MONSOON TROUGH IS RESULTING IN 
AN AREA OF NE WINDS 20 KT COVERING FROM 10N TO 14N BETWEEN 112W 
AND 122W. THESE WINDS WERE SAMPLED BY THE MOST RECENT OSCAT 
PASS. THE SAME SCATTEROMETER PASS PROVIDED OBSERVATIONS OF SE 
WINDS OF 20 KT S OF THE MONSOON TROUGH ROUGHLY FROM THE EQUATOR 
TO 04N BETWEEN 110W AND 120W. TROPICAL CYCLONE FORMATION IS NOT 
EXPECTED IN ASSOCIATION WITH THESE LOWS DURING THE NEXT 48 HOURS.
BEYOND THIS PERIOD...THE GFS MODEL SUGGESTS THE DEVELOPMENT OF 
THE EASTERNMOST LOW PRES BY SUN...WITH THE LOW POSSIBLY BECOMING 
BETTER MON AND TUE. 

ELSEWHERE...CROSS EQUATORIAL SW SWELLS ARE RAISING SEAS TO 8 FT 
ACROSS THE SOUTH-CENTRAL WATERS TODAY AND WILL CONTINUE TO PUSH 
NORTH THROUGH THE WEEKEND.  

GAP WINDS OF 20 TO 25 KT ARE EXPECTED TO CONTINUE OVER THE GULF 
OF PAPAGAYO AS FRESH TO STRONG TRADE WIND FLOW IN THE SW 
CARIBBEAN FUNNELS THROUGH THE GAP. THE WINDS ARE GREATEST DURING 
THE OVERNIGHT AND EARLY MORNING HOURS WITH THE ASSISTANCE OF THE 
NOCTURNAL DRAINAGE FLOW. THIS WILL BUILD SEAS TO 9 FT ON FRIDAY. 

THE TROPICAL WAVE CURRENTLY MOVING ACROSS SE MEXICO WILL FORCE 
NLY WINDS OF 20-25 KT THROUGH THE GULF OF TEHUANTEPEC BEGINNING 
EARLY FRI MORNING.  

$$
GR