000
AXPZ20 KNHC 280327
TWDEP 

TROPICAL WEATHER DISCUSSION    
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC SUN JUN 28 2009

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 
0300 UTC.

...TROPICAL WAVE...

TROPICAL WAVE IS ALONG 90W N OF 10N MOVING W 10-15 KT. THE NRN 
PORTION OF THE WAVE...OVER THE NW CARIBBEAN...REMAINS ACTIVE AND 
IT BEING MONITORED FOR TROPICAL CYCLONE DEVELOPMENT. REFER TO 
THE ATLANTIC TROPICAL WEATHER DISCUSSION...MIATWDAT...FOR MORE 
DETAILS. THE SOUTHERN PORTION OF THE WAVE IS ENHANCING 
CONVECTION OVER PORTIONS OF CENTRAL AMERICA...STRONGEST OVER 
GUATEMALA AND WRN HONDURAS. 

...ITCZ...

THE ITCZ AXIS IS CENTERED ALONG 10N86W TO 09N108W TO 13N121W TO 
07N140W. SCATTERED MODERATE CONVECTION IS FROM 06N TO 11N E OF 
110W. SCATTERED MODERATE TO STRONG CONVECTION IS FROM 07N TO 11N 
BETWEEN 123W AND 134W. 

...DISCUSSION...

SUBTROPICS...
A MID-UPPER TROUGH EXTENDS FROM 30N135W TO 20N128W WITH WV SAT 
IMAGERY SHOWING A CUT OFF LOW DEVELOPING NEAR THE BASE OF THE 
TROUGH. RIDGING EXISTS BOTH E AND W OF THE TROUGH. WIDESPREAD 
DRY AIR IS NOTED ACROSS THE ENTIRE REGION ABOVE THE LOW-MID 
LEVEL STRATOCUMULUS DECK...LEADING TO ABUNDANT STABILITY. 
VISIBLE IMAGERY REVEALS A SHEAR AXIS ALONG 22N W OF ABOUT 130W. 
THE TIGHTENED PRESSURE GRADIENT BETWEEN THIS BOUNDARY AND A 1032 
MB HIGH IS PRODUCING 20 KT NE TO E WINDS AS INDICATED BY 
SCATTEROMETER DATA. THE COMBINATION OF THE RIDGE PULLING N AND A 
WEAK SFC TROUGH DEVELOPING OVER THE SUBTROPICS SHOULD ALLOW THE 
20 KT WINDS TO SHRINK IN COVERAGE SUN AND DIMINISH BY MON. 
HOWEVER...SEAS WILL REMAIN ELEVATED UP TO 10 FT OVER THE NEXT 
COUPLE OF DAYS AS MIXED N AND SW SWELL CONTINUE TO PROPAGATE 
AWAY FROM CYCLONES N AND S OF THE AREA. 

TROPICS...
THE MOST NOTABLE FEATURE ACROSS THE TROPICS IS A SFC TROUGH 
ALONG 13N129W 07N132W. SAT IMAGERY SHOWS EVIDENCE OF A WEAK 
CIRCULATION NEAR 10N130W WITH AN ASSOCIATED AREA OF MODERATE TO 
STRONG CONVECTION WITHIN 180 NM E OF THE ESTIMATED CENTER AND A 
MORE LINEAR LINE OF CONVECTION FROM 08N TO 11N BETWEEN 
130W-135W. A BROADER LOOK AT VIS/IR IMAGERY SHOWS ANOTHER WEAK 
SWIRL NEAR 07N137W AND ENHANCED CLOUDINESS/CONVECTION NE OF THE 
TROUGH FROM 11N-14N BETWEEN 120W-125W. GLOBAL MODELS ARE IN 
AGREEMENT IN SHOWING LITTLE OR NO DEVELOPMENT OF THIS 
DISORGANIZED SYSTEM. 

CROSS-EQUATORIAL SLY WINDS ARE NEAR 20 KT S OF 05N BETWEEN 82W 
AND 107W AND NEAR THE AFOREMENTIONED SFC TROUGH FROM 02N TO 07N 
BETWEEN 122W AND 130W. SE-S WINDS NEAR 20 KT ARE EXPECTED TO 
PERSIST ACROSS MUCH OF THE AREA S OF THE ITCZ...ESPECIALLY W OF 
95W...OVER THE NEXT FEW DAYS AS THE PRESSURE GRADIENT TIGHTENS 
BETWEEN THE SUBTROPICAL RIDGES AND THE ITCZ. 

$$
CANGIALOSI