000
AXPZ20 KNHC 272117
TWDEP 

TROPICAL WEATHER DISCUSSION    
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC SAT JUN 27 2009

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

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2100 UTC.

...TROPICAL WAVE...

TROPICAL WAVE IS ALONG 89W N OF 06N 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 SUPPORTING A BROAD 
AREA OF MODERATE CONVECTION FROM 03N TO 10N BETWEEN 80W AND 95W.

...ITCZ...

THE ITCZ AXIS IS CENTERED ALONG 06N79W TO 09N87W TO 07N105W TO 
11N123W TO 08N140W. SCATTERED MODERATE ISOLATED STRONG 
CONVECTION IS FROM 03N TO 10N BETWEEN 80W AND 95W. SCATTERED 
MODERATE CONVECTION IS WITHIN 240 NM N AND 180 NM S OF THE AXIS 
BETWEEN 95W AND 118W. SCATTERED MODERATE TO STRONG CONVECTION IS 
FROM 08N TO 12N BETWEEN 126W AND 136W.

...DISCUSSION...

SUBTROPICS...
A MID-UPPER TROUGH EXTENDS FROM 30N135W TO 20N130W 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. VISIBLE IMAGERY REVEALS A SHEAR AXIS 
ALONG 22N W OF ABOUT 132W. THE TIGHTENED PRESSURE GRADIENT 
BETWEEN THIS BOUNDARY AND A 1032 MB HIGH IS PRODUCING 20 KT NE 
TO E WINDS AS INDICATED BY EARLIER QUIKSCAT DATA. THE 
COMBINATION OF THE RIDGE PULLING N AND A WEAK SFC TROUGH 
DEVELOPING OVER THE SUBTROPICS SHOULD ALLOW THE 20 KT WINDS TO 
GRADUALLY SHRINK IN COVERAGE SUN AND DIMINISH BY MON. 
HOWEVER...SEAS WILL REMAIN ELEVATED UP TO 10 FT AS MIXED NW AND 
SW SWELL CONTINUE TO PROPAGATE AWAY FROM CYCLONES N AND S OF THE 
AREA. 

TROPICS...
MOST NOTABLE FEATURE ACROSS THE TROPICS IS A SFC TROUGH ALONG 
129W/130W FROM 07N TO 13N. SAT IMAGERY SHOWS EVIDENCE OF A WEAK 
CIRCULATION NEAR 10N130W AND AN ASSOCIATED AREA OF MODERATE TO 
STRONG CONVECTION OVER THE ERN SEMICIRCLE FROM 08N TO 12N 
BETWEEN 126W AND 130W. A BROADER LOOK AT VIS/IR IMAGERY SHOWS 
ANOTHER WEAK SWIRL NEAR 07N137W AND ENHANCED CONVECTION NE OF 
THE TROUGH FROM 11N-14N BETWEEN 120W-123W. GLOBAL MODELS ARE IN 
AGREEMENT IN SHOWING LITTLE OR NO DEVELOPMENT FROM THIS SYSTEM. 

CROSS-EQUATORIAL SLY WINDS ARE NEAR 20 KT S OF 05N BETWEEN 80W 
AND 105W AND NEAR THE AFOREMENTIONED SFC TROUGH FROM 03N TO 08N 
BETWEEN 122W AND 128W. SE-S WINDS NEAR 20 KT ARE EXPECTED TO 
PERSIST ACROSS MUCH OF THE AREA S OF THE ITCZ...ESPECIALLY W OF 
100W...OVER THE NEXT FEW DAYS AS THE PRESSURE GRADIENT TIGHTENS 
BETWEEN THE SUBTROPICAL RIDGES AND THE ITCZ. 

$$
CANGIALOSI