000
AXPZ20 KNHC 011540
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC SUN AUG 01 2010

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

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1500 UTC.

...ITCZ...
THE INTERTROPICAL CONVERGENCE ZONE AXIS IS ALONG 09N83W TO 
11N94W TO 07N104W TO 15N115W TO 11N125W TO 11N140W. ISOLATED 
MODERATE CONVECTION IS WITHIN 120 NM EITHER SIDE OF AXIS BETWEEN 
83W AND 92W. SCATTERED MODERATE CONVECTION IS NOTED FROM 08N TO 
10N BETWEEN 104W AND 106W. SCATTERED MODERATE TO ISOLATED STRONG 
CONVECTION IS FROM 9N TO 12N W OF 127W.  

...DISCUSSION...

ALOFT...AN UPPER LEVEL ANTICYCLONE LIES OVER THE NW WATERS NEAR 
19N129W AND EXTENDS A RIDGE TO ITS NE TO 26N127W AS WELL AS TO 
ITS SW TO NEAR 14N133 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 127W. THIS ANTICYCLONE 
WILL WEAKEN IN ABOUT 24 HOURS AS A DEEP LAYER TROUGH APPROACHES 
THE NW CORNER OF THE AREA...AND AN UPPER LEVEL LOW CURRENTLY 
NEAR 21N123W DRIFTS WWD. ANOTHER UPPER LEVEL LOW IS SEEN ON 
WATER VAPOR IMAGERY NEAR THE MARIAS ISLANDS. A RIDGE EXTENDS 
THROUGH THE BAY OF CAMPECHE SOUTHWESTWARD INTO THE EPAC TO NEAR 
14N105W. 30-40 KT NORTHEASTERLY UPPER LEVEL WINDS DOMINATE THE 
REGION E OF 110W.  

AT THE SURFACE...AN AREA OF DISTURBED WEATHER LOCATED ABOUT 390 
NM SOUTHWEST OF THE SOUTHERN TIP OF BAJA CALIFORNIA IS MOVING 
WESTWARD TO WEST-NORTHWESTWARD AT 9 KT. SOME SLOW DEVELOPMENT OF 
THIS DISTURBANCE IS POSSIBLE BEFORE IT REACHES COOLER WATERS IN 
A COUPLE OF DAYS. THERE IS A LOW CHANCE OF THIS SYSTEM BECOMING 
A TROPICAL CYCLONE DURING THE NEXT 48 HOURS. SCATTERED MODERATE 
CONVECTION IS NOTED IN A CLUSTER LOCATED ABOUT 150 NM SE 
QUADRANT OF LOW. 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 AROUND 140 NM NW QUADRANT. 
A SURFACE TROUGH EMBEDDED IN THE ITCZ EXTENDS FROM 13N134W TO 
8N135W. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS 
WITHIN 90 NM EITHER SIDE OF TROUGH AXIS.

SURFACE HIGH PRES LOCATED NW OF AREA...ANALYZED 1030 MB NEAR 
39N144W ON THE 12Z SURFACE MAP...EXTENDS A RIDGE OVER THE N 
WATERS MAINLY N OF 19N 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 TODAY AND MON.

$$
GR