000
AXPZ20 KNHC 012133
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC SUN AUG 01 2010

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

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2100 UTC.

...ITCZ...
THE INTERTROPICAL CONVERGENCE ZONE AXIS IS ALONG 09N84W TO 
08N90W TO 11N95W TO 11N110W THEN RESUMES AT 14N118W TO 11N140W. 
SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS FROM 07N T0 
10N BETWEEN 97W AND 101W. SIMILAR CONVECTION IS NOTED FROM 9N TO 
12N W OF 128W. 

...DISCUSSION...

ALOFT...AN UPPER LEVEL ANTICYCLONE LIES OVER THE NW WATERS NEAR 
18N129W AND EXTENDS A RIDGE TO ITS NE TO 27N126W AS WELL AS TO 
ITS SW TO NEAR 14N140W THEN TO W OF THE AREA TO NEAR 14N150W. 
UPPER DIFFLUENCE ASSOCIATED WITH THIS SYSTEM IS HELPING TO 
INDUCE CONVECTION ALONG THE ITCZ W OF 128W. THIS ANTICYCLONE 
WILL WEAKEN IN ABOUT 24 HOURS AS A DEEP LAYER TROUGH APPROACHES 
THE NW CORNER OF THE FORECAST AREA...AND AN UPPER LEVEL LOW 
CURRENTLY NEAR 21N124W DRIFTS WWD. ANOTHER UPPER LEVEL LOW IS 
SEEN ON WATER VAPOR IMAGERY NEAR THE MARIAS ISLANDS. A RIDGE 
EXTENDS THROUGH THE BAY OF CAMPECHE AND SE MEXICO INTO THE EPAC 
TO NEAR 14N105W. 30-40 KT NORTHEASTERLY UPPER LEVEL WINDS 
DOMINATE THE TROPICS E OF 110W. THESE WINDS ARE ADVECTING 
MID/UPPER LEVEL MOISTURE FROM THE CONVECTION IN THE SW CARIBBEAN 
INTO THE EPAC THROUGH CENTRAL AMERICA.    

AT THE SURFACE...AN AREA OF DISTURBED WEATHER LOCATED ABOUT 370 
NM SOUTHWEST OF THE SOUTHERN TIP OF BAJA CALIFORNIA IS MOVING 
WESTWARD TO WEST-NORTHWESTWARD AT 9 KT. THE SHOWER AND TSTM 
ACTIVITY ASSOCIATED WITH THIS SYSTEM REMAINS DISORGANIZED...AND 
IT IS FORECAST TO REACH COOLER WATERS IN A DAY OR TWO...MAKING 
ITS DEVELOPMENT LESS LIKELY. THERE IS A LOW CHANCE OF THIS LOW 
BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS. SCATTERED 
MODERATE CONVECTION IS NOTED WITHIN 90 NM E SEMICIRCLE. 

A 1008 MB SURFACE LOW IS NEAR 09N98W. SE WINDS OF 20KT AND SEAS 
TO 9 FT CAN BE FOUND WITHIN 120 NM SE QUADRANT OF LOW. SCATTERED 
SHOWERS AND TSTMS ARE NEAR THE LOW CENTER...AND IN A BAND 
LOCATED WITHIN ABOUT 200 NM NW QUADRANT. A WEAK SURFACE TROUGH 
EMBEDDED IN THE ITCZ EXTENDS FROM 12N133W TO 10N134W. SCATTERED 
MODERATE TO ISOLATED STRONG CONVECTION IS MAINLY WITHIN 90 NM E 
OF THE TROUGH AXIS.

SURFACE HIGH PRES LOCATED NW OF AREA...ANALYZED 1030 MB NEAR 
38N142W ON THE 18Z SURFACE MAP...EXTENDS A RIDGE OVER THE N 
WATERS MAINLY N OF 18N AND W OF 120W. THE PRESSURE GRADIENT 
BETWEEN THIS HIGH AND THE ITCZ IS RESULTING IN A SMALL AREA OF 
20 KT TRADES FROM 10N TO 16N W OF 137W. THE HIGH PRESSURE CENTER 
WILL MOVE N OVER THE NEXT COUPLE OF DAYS WHICH WILL DECREASE THE 
TRADES BELOW 20 KT BY 48 HOURS. SOUTHERLY SWELLS ARE AFFECTING 
THE REGION S OF 10N AND WILL CONTINUE TO SUBSIDE TONIGHT AND MON.

$$
GR