000
AXPZ20 KNHC 290305
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC FRI AUG 29 2008

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 
0230 UTC.

...TROPICAL WAVES...

TROPICAL WAVE IS LOCATED ALONG 99W S OF THE MEXICAN COAST MOVING 
W 10 KT. THE WAVE IS EMBEDDED WITHIN AN ENVIRONMENT OF LOW-LEVEL 
WESTERLIES...WHICH IS PRODUCING THE SLOW PROPAGATION...AND THUS 
HAS A VERY WEAK SIGNATURE. MOST OF THE DEEP CONVECTION IS 
ORIENTED LINEARLY ALONG THE ITCZ/MONSOON TROUGH AXIS. SCATTERED 
MODERATE/STRONG CONVECTION ALSO LIES AT THE N END OF THE AXIS 
WITHIN 60 NM OF THE MEXICAN COAST BETWEEN 97W-102W.
     
...ITCZ...

ITCZ AXIS IS CENTERED FROM 09N80W TO 13N93W TO 11N108W TO 
14N117W TO 10N130W TO 10N140W. SCATTERED MODERATE CONVECTION 
FROM 05N-11N BETWEEN 82W-95W. SCATTERED MODERATE FROM 08N-13N 
BETWEEN 98W-112W. SCATTERED MODERATE/STRONG WITHIN 120 NM OF 
AXIS W OF 123W.

...DISCUSSION...

TROPICS...
TWO STRONG UPPER LEVEL ANTICYCLONES...ONE CENTERED W OF THE BAJA 
PENINSULA AND THE OTHER S OF THE EQUATOR NEAR 12S104W...ARE 
PRODUCING A FAIRLY STRONG EASTERLY JET ALOFT STRADDLING THE 
EQUATOR WITH MAXIMUM WIND SPEEDS OF 45 KT. THE EASTERLIES ARE 
ABOUT AS FAR W AS 130W AND ARE PRODUCING WEAK DIFFLUENCE OVER 
THE ITCZ/MONSOON TROUGH REGION S OF MEXICO AND CENTRAL AMERICA. 
THE MONSOON TROUGH IS QUITE PRONOUNCED AT THE MOMENT WITH 
LOW-LEVEL WESTERLIES EXTENDING WELL TO THE COAST. A WEAK LOW 
ALONG THIS AXIS HAS DEGENERATED INTO A SURFACE TROUGH FROM 
18N114W TO 12N118W.

SUBTROPICS...
AS MENTIONED ABOVE...A STRONG UPPER LEVEL ANTICYCLONE IS 
CENTERED W OF THE BAJA PENINSULA NEAR 25N120W WITH 
MODERATE/STRONG SUBSIDENCE EXTENDING FROM THE GULF OF CALIFORNIA 
WWD TO 140W. THE ANTICYCLONE IS BOUNDED BY TWO UPPER LOWS...ONE 
ALONG THE ARIZONA/MEXICAN BORDER AND THE OTHER NEAR 32N135W. THE 
UPPER LOW OVER THE BORDER IS HELPING TO PRODUCE SCATTERED TSTMS 
N OF 27.5N E OF THE GULF OF CALIFORNIA BUT IS ALSO DRAWING A 
NARROW BELT OF DRY AIR FROM THE W INLAND ACROSS PARTS OF NW 
MEXICO. STRONG NORTHERLY LOW-LEVEL FLOW CONTINUES ALONG THE 
COAST OF CALIFORNIA WITH NORTHERLY SWELLS MOVING INTO THE AREA S 
OF 30N. THE FLOW WILL BE REINFORCED BY A COLD FRONT WHICH WILL 
DROP S TO 30N BY SAT EVENING.

$$
BERG