000
AXPZ20 KNHC 050311
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC THU AUG 05 2010

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.

...SPECIAL FEATURE...

A 1007 MB LOW IS POSITIONED NEAR 14.6N96.9W AND IS MOVING W AT 
10 KT. NUMEROUS MODERATE AND ISOLATED STRONG CONVECTION IS 
WITHIN 300 NM IN THE W QUADRANT OF THE LOW CENTER WITH 20 TO 25 
KT WINDS N OF 15N BETWEEN 94W AND 98W. RADAR FROM MEXICO IS
INDICATING VERY HEAVY RAINFALL OCCURRING OVER LAND S OF 18N 
BETWEEN 98W AND 100W. CONDITIONS ARE CONDUCIVE FOR ADDITIONAL 
DEVELOPMENT AND THIS SYSTEM COULD BECOME A TROPICAL DEPRESSION 
AT ANY TIME TONIGHT OR THURSDAY. THERE IS A HIGH CHANCE OF THIS 
LOW BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS AS IT 
MOVES WESTWARD AT ABOUT 10-12 KT. INTERESTS ALONG THE SOUTHERN 
COAST OF MEXICO SHOULD MONITOR THE PROGRESS OF THIS SYSTEM.

...ITCZ...

ITCZ AXIS ALONG 11N86W TO 15N96W TO 14N99W TO 14N108W TO 13N111W 
TO 10N126W TO 10N140W. SCATTERED MODERATE CONVECTION IS WITHIN 
120 NM S OF THE AXIS BETWEEN 101W AND 104W. SCATTERED MODERATE 
AND ISOLATED STRONG CONVECTION IS WITHIN 120 NM S OF THE AXIS 
BETWEEN 105W AND 108W...WITHIN 150 NM N OF THE AXIS BETWEEN 112W 
AND 123W...AND WITHIN 120 NM S OF THE AXIS BETWEEN 118W AND 
124W. 
 
...DISCUSSION...

AN UPPER LEVEL ANTICYCLONE IS OVER THE FAR NW WATERS NEAR 
24N140W WITH AN UPPER RIDGE EXTENDING TO THE NE TO NEAR 28N127W 
AND TO THE SW WEST OF THE DISCUSSION AREA. ANOTHER UPPER LEVEL 
ANTICYCLONE IS CENTERED W OF THE SOUTHERN TIP OF THE BAJA 
PENINSULA NEAR 24N114W. IN BETWEEN THE TWO ANTICYCLONES THERE IS 
A COL AREA. VERY DRY AIR DUE TO MODERATE TO STRONG SUBSIDENCE 
COVERS THE ENTIRE AREA N OF 20N AND W OF 115W. AN INVERTED 
TROUGH EXTENDS FROM THE ITCZ NEAR 11N138W TO 22N128W. ANOTHER 
INVERTED TROUGH IS DEVELOPING FROM 13N111W TO 21N111W.

EASTERLY/ZONAL FLOW PREVAILS ACROSS THE REMAINDER OF THE 
DISCUSSION AREA IN THE DEEP TROPICS S OF 20N. UPPER LEVEL 
MOISTURE RESULTING FROM ITCZ CONVECTION IS BEING ADVECTED TO THE 
WEST AS A RESULT OF THE PERSISTENT EASTERLY WINDS. 
AFTERNOON/EVENING CONVECTION THAT DEVELOPED OVER MEXICO AND 
CENTRAL AMERICA IS ALSO BEING ADVECTED JUST OFFSHORE INTO THE E 
PACIFIC WITH THE EASTERLY FLOW.

ELSEWHERE AT THE SURFACE...A TROUGH IS EMBEDDED IN THE ITCZ 
EXTENDING FROM 12N126W TO 10N132W. SCATTERED MODERATE AND 
ISOLATED STRONG CONVECTION IS WITHIN 75 NM OF THE TROUGH AXIS S 
OF 12N.

CROSS EQUATORIAL SOUTHERLY SWELLS CONTINUE TO AFFECT THE 
SOUTHERN PORTION OF THE BASIN MAINLY S OF 10N AND W OF 106W AND 
THEY WILL CONTINUE TO PROPAGATE ACROSS THE SOUTHERN PORTION UP 
TO 8 TO 9 FT THROUGH 48 HOURS.

$$
LEWITSKY