000
AXPZ20 KNHC 190311
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC THU AUG 19 2010

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN
FROM THE EQUATOR TO 32N...EAST OF 140W.

BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0300 UTC. 

...ITCZ...

THE INTERTROPICAL CONVERGENCE ZONE AXIS IS ALONG 12N112W TO 
09N115W TO 11N127W TO 09N140. SCATTERED MODERATE TO ISOLATED 
STRONG CONVECTION IS NOTED FROM 08N TO 11N BETWEEN 97W AND 
105W...AND WITHIN 60 NM S OF AXIS BETWEEN 105W AND 113W.      

...DISCUSSION...

ALOFT...A BROAD UPPER LEVEL ANTICYCLONIC CIRCULATION CENTERED 
OVER CENTRAL TEXAS EXTENDS A RIDGE ACROSS NORTH-CENTRAL MEXICO 
INTO THE EPAC COVERING MUCH OF THE AREA N OF 15N ASIDE FROM THE 
FAR NW CORNER WHERE SOUTHWESTERLY FLOW IN THE 45 TO 50 KT RANGE 
IS NOTED AHEAD OF AN UPPER-LEVEL LOW LOCATED NW OF THE FORECAST 
AREA NEAR 36N141W. MODERATE TO STRONG UPPER LEVEL SUBSIDENCE AND 
THE IMPLIED DRY AIR MASS DOMINATES THE REGION N OF 20N W OF 
127W. AN INVERTED TROUGH EXTENDS FROM 21N133W TO 11N137W. E TO 
SE WINDS OF 30 TO 35 KT CAN BE FOUND BEHIND THE TROUGH AXIS.  
EASTERLY FLOW PREVAILS IN THE DEEP TROPICS.  

AT THE SURFACE...A WEAK SURFACE RIDGE DOMINATES THE N WATERS 
MAINLY N OF 18N AND W OF 120W. A TROUGH LIES PARALLEL TO THE W 
COAST OF MEXICO AND STRETCHES FROM 20N107W TO 12N94W. SCATTERED 
MODERATE CONVECTION IS NOTED WITHIN 120 NM EITHER SIDE OF TROUGH 
WITH THE EXCEPTION OF SCATTERED MODERATE TO ISOLATED STRONG 
CONVECTION NEAR THE NORTHERN END OF THE AXIS. S TO SW WINDS UP 
TO 20 KT ARE BLOWING SOUTH OF THE TROUGH PARTICULARLY FROM 04N 
TO 10N BETWEEN 92W AND 110W. AN EARLIER ASCAT PASSES VERIFIED 
THE EXISTENCE OF THESE WINDS SPEEDS. ANOTHER SURFACE TROUGH 
EXTENDS FROM 17N133W TO 10N128W WITH A WEAK 1012 MB LOW LOCATED 
NEAR 13N131W. A SWIRL OF LOW CLOUDS IS ASSOCIATED WITH THE LOW.

CROSS EQUATORIAL SW SWELLS CONTINUE TO PROPAGATE NWD ACROSS THE 
SOUTH-CENTRAL WATERS BUILDING SEA HEIGHTS UP TO 10 FT. THIS 
SWELL EVENT IS BEGINNING TO MAKE ITS WAY E OF THE GALAPAGOS 
ISLANDS AND SEAS WILL REACH 8 FT OFF THE COAST OF WESTERN PANAMA 
BY THU MORNING.

$$
GR