000
AXPZ20 KNHC 021555
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC THU SEP 02 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 
1545 UTC.

...SPECIAL FEATURES...
SURFACE LOW PRES CENTER 1003 MB NEAR 300 NM S-SE OF SOUTHERN TIP 
OF BAJA CALIFORNIA PENINSULA AT 18N108W.  DEEP CONVECTION NOTED 
WITHIN 240 NM NW AND 150 NM SE SEMICIRCLES.  STRONG SURFACE WIND 
EXTEND 75 NM FROM CENTER EXPECTED TO INCREASE AND CONTINUE TO 
ADVECT TROPICAL MOISTURE INTO ITS SW QUADRANT.  UPPER LEVEL 
ENVIRONMENT EXPECTED TO BECOME MORE FAVORABLE DURING NEXT 24-36 
HRS AND THERE IS HIGH PROBABILITY OF SYSTEM BECOMING A TROPICAL 
CYCLONE DURING NEXT 48 HOURS. 

SECOND SURFACE LOW PRES CENTER 1007 MB IN GULF OF TEHUANTEPEC AT 
14N94W IS EMBEDDED IN MONSOONAL FLOW AND NOT EXPECTED TO DEVELOP 
TROPICAL CHARACTERISTICS ALTHOUGH ITS UPPER LEVEL ENVIRONMENT IS 
NOT ADVERSE AT ALL.  LARGE BURST OF DEEP CONVECTION OVER N 
QUADRANT ENHANCED BY CIRCULATION JUSTIFIES MONITORING SYSTEM 
CLOSELY.

...ITCZ...
AXIS ALONG 12N108W TO 09N120W TO 08N130W TO 10N140W.  SCATTERED 
MODERATE ISOLATED STRONG CONVECTION WITHIN 120 NM N OF AXIS FROM 
120W-130W...WITHIN 60 NM OF AXIS FROM 115W-120W AND WITHIN 60 NM 
S OF AXIS W OF 133W. 

...DISCUSSION...
DOUBLE CENTERED UPPER LEVEL ANTICYCLONE OVER BASIN N OF 16N W OF 
114W MAINTAINS DRY ANTICYCLONIC FLOW OVER REGION AND N OF 20N E 
OF 114W.  WEAK SHEAR ZONE BETWEEN UPPER ANTICYCLONE CENTERS 
PROVIDE WINDOW FOR ABOVE MENTIONED LOW PRES CENTER TO INTENSIFY 
BEFORE STEERED W BY FLOW.  STEADY NE FLOW ALOFT OVER REGION S OF 
16N E OF 114W CURTAILS TROPICAL DEVELOPMENT OF SECOND LOW PRES 
BUT DOES ADVECT PLENTY OF MOISTURE ALONG ITCZ AXIS E OF 102W. 
WEAK UPPER LEVEL CYCLONE AT 08N131W ALSO PROVIDES TROPICAL 
MOISTURE TO ITCZ AXIS W OF 118W. 

AT THE SURFACE...
CENTRAL PAC RIDGE EXTEND FROM HIGH PRES CENTER W NW OF REGION TO 
20N120W KEEPS NW PART OF BASIN UNDER DRY AND STABLE AIR MASS. 

STRENGTHENING LOW PRES S OF BAJA CALIFORNIA PRODUCING STRONG SW 
BREEZE FROM 05N-15N BETWEEN 101W-105W WITH SEAS BUILDING TO 11 
FT.  SIMILARLY LOW PRES IN GULF OF TEHUANTEPEC ENHANCES STRONG 
SW BREEZE FROM 06N-08N E OF 85W WITH SEAS TO 9 FT.  BOTH AREAS 
EXPECTED TO REMAIN WITH STRONG WINDS THROUGH 48 HRS. 

$$
WALLY BARNES