000
AXPZ20 KNHC 300856
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC SAT SEP 30 2006

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W. THE FOLLOWING INFORMATION IS 
BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND 
METEOROLOGICAL ANALYSIS.

BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0830 UTC.

ITCZ...
AXIS IS CENTERED ALONG 9N83W 10N97W 9N108W 12N130W 9N135W 
8N140W. SCATTERED MODERATE TO STRONG CONVECTION WITHIN 180 NM S 
OF THE AXIS IN THE GULF OF PANAMA. SCATTERED MODERATE CONVECTION 
120 NM ON EITHER SIDE OF AXIS BETWEEN 84W AND 98W. SCATTERED 
MODERATE CONVECTION WITHIN 90 S OF AXIS BETWEEN 101W AND 110W. 

TROPICAL WAVES/LOWS...
A TROPICAL WAVE IS ALONG 91W N OF 3N MOVING W 15 KT. SCATTERED 
MODERATE CONVECTION WITHIN 90 NM OF COAST OF CENTRAL AMERICA 
BETWEEN 87W AND 93W...AND ALONG THE ITCZ.

...DISCUSSION...
UPPER PATTERN STARTING TO BECOME MORE AMPLIFIED TO THE N OF THE 
AREA AS AN UPPER TROUGH LIFTS OUT AHEAD A RIDGE BUILDING OVER 
THE CENTRAL PACIFIC. THIS WILL RESULT IN THE 1025 MB SURFACE 
RIDGE CENTERED NW OF THE AREA NEAR 35N140W BUILDING EWD TO THE N 
OF 18N AS THE UPPER RIDGE SHIFTS E. MEANWHILE...QUIKSCAT DATA 
FROM YESTERDAY EVENING IS SHOWING WEAK TROUGH S OF 12N NEAR 132W 
ALONG THE ITCZ. MODERATE TO FRESH TRADES PERSIST BETWEEN THIS 
TROUGH AND THE HIGH PRESSURE TO THE NORTH. THE TROUGH WILL 
CONTINUE TO DAMPEN OUT...BUT EXPECT FRESH TRADES TO CONTINUE 
THROUGH THE 48 HOURS AS SURFACE RIDGE BUILDS N OF THE AREA.

FURTHER S...TROPICAL UPPER LOW IS CENTERED NEAR 5N97W WITH UPPER 
RIDGE TO THE E OVER COSTA RICA AND PANAMA NEAR 9N84W. SLY UPPER 
DIVERGENCE BETWEEN THESE SYSTEMS IS ENHANCING CONVECTION MAINLY 
BETWEEN 93W AND 99W ALONG THE ITCZ AND THE TROPICAL WAVE ALONG 
92W. THE TROPICAL WAVE AND THE FAVORABLE UPPER FLOW ARE ALSO 
ENHANCING NOCTURNAL COASTAL CONVECTION OF THE SALVADORAN COAST. 

MODERATE N WINDS AHEAD OF THE WAVE OVER THE TEHUANTEPEC ISTHMUS 
ARE EVIDENT ON LATEST QUIKSCAT IMAGERY AND COASTAL SURFACE 
OBSERVATIONS. GAP WINDS SHOULD STAY BELOW 20 KT THROUGH TONIGHT 
IN GULF OF TEHUANTEPEC...BUT MAY START TO INCREASE BY LATE 
SUNDAY AS HIGH PRESSURE BUILDS OVER THE GULF OF MEXICO TO THE 
NORTH.


$$
CHRISTENSEN