000
AXPZ20 KNHC 182127
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC SAT JUL 18 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 WAVES...

TROPICAL WAVE ALONG 101W FROM 05N TO 13N MOVING WEST 15 TO 20 
KT.  SCATTERED MODERATE WITH ISOLATED STRONG CONVECTION IS 
WITHIN 360 NM E OF AXIS SOUTH OF 11N. THIS CONVECTION SHOWS NO 
SIGNS OF ORGANIZATION.
 
TROPICAL WAVE ALONG 124W FROM 05N TO 15N MOVING WEST 15 KT. 
ISOLATED TO WIDELY SCATTERED MODERATE CONVECTION NEAR THE WAVE 
AXIS. THE CONVECTION HAS DIMINISHES DURING THE LAST 24 HOURS AND 
SHOWS NO SIGNS OF ORGANIZATION. SOME OF THE COMPUTER FORECAST 
MODELS SUGGEST THE DEVELOPMENT OF A LOW PRES ALONG THE WAVE AXIS 
IN ABOUT 24 TO 48 HOURS. 

...ITCZ...

THE INTERTROPICAL CONVERGENCE ZONE IS ALONG THE LINE...07N77W TO 
07N100W TO 09N140W. SCATTERED MODERATE WITH ISOLATED STRONG 
CONVECTION IS WITHIN 120 NM EITHER SIDE OF THE ITCZ FROM 85W TO 
100W. SCATTERED MODERATE WITH ISOLATED STRONG CONVECTION IS 
WITHIN 200 NM OF THE POINT 10N109W. SCATTERED MODERATE WITH 
ISOLATED STRONG CONVECTION IS WITHIN 75 NM OF THE POINT 
12.5N121W.

...DISCUSSION...

DEEP LAYER TROUGH IS WEST OF THE AREA WITH ASSOCIATED SOUTHERLY 
FLOW WEST OF A LINE THROUGH 32N128W TO 18N140W. THE NORTHEAST 
PART OF THIS AREA IS MOIST IN THE MIDDLE LEVELS WITH OVERCAST 
MIDDLE CLOUDS BECAUSE OF THE MIDDLE LEVEL MOISTURE ASSOCIATED 
WITH THE REMNANTS OF DOLORES. OTHERWISE THIS AREA IS DRY AND 
CLOUD FREE IN THE MIDDLE AND UPPER LEVELS WITH MOSTLY BROKEN TO 
OVERCAST STRATOCUMULUS IN THE LOWER LEVELS. THE TROUGH IS  
FORECAST TO CHANGE LITTLE THROUGH THE NEXT SEVERAL DAYS AND 
DRIFT A LITTLE EASTWARD. 

ANOTHER DEEP LAYER TROUGH EXTENDS ALONG 125W NORTH OF 15N. THIS 
FEATURE IS PART OF THE CYCLONIC FLOW ASSOCIATED WITH REMNANTS OF 
DOLORES. MOIST SOUTHERLY FLOW EXTENDS WELL EAST OF THE WAVE AXIS 
WITH SOME PATCHY UPPER CLOUDS MAINLY NORTH OF 25N FROM 117W TO 
125W. 

ANOTHER SMALLER DEEP LAYER TOUGH EXTENDS SOUTHWEST OF MEXICO 
ALONG A LINE FROM NEAR 22N105W TO NEAR 15N120W. THIS AREA IS 
OBSERVED TO BE CLOUD FREE WITH LITTLE CONVECTION AT THIS TIME.

REMAINDER OF THE AREA IS WEAKLY ANTICYCLONIC IN THE MIDDLE AND 
UPPER LEVELS. THE AREA WEST OF 125W NORTH OF THE ITCZ IS DRY AND 
CLOUD FREE IN THE MIDDLE AND UPPER LEVELS. BROKEN STRATOCUMULUS 
IS NORTH OF 30N AND ALSO WEST OF 130W.

NE TO E GAP WINDS IN AND DOWNSTREAM FROM THE GULF OF PAPAGAYO OF 
20 TO 25 KNOTS WILL CONTINUE THROUGH AT LEAST THE NEXT SEVERAL 
DAYS.

CROSS EQUATORIAL SE AND SW SWELLS WITH FRESH SOUTHERLY LOW LEVEL 
WIND FLOW RESULT IN SEAS TO 9 FT OVER WATERS S OF 10N W OF THE 
GALAPAGOS ISLANDS. 

EXCEPT FOR THE BROAD WEAK LOW THAT IS THE REMNANTS OF DOLORES A 
WEAK SURFACE RIDGE IS NORTH OF 15N WEST OF 110W. ELSEWHERE A 
WEAK TROUGH IS ANALYZED AT THE SURFACE.

$$
LL