000
AXPZ20 KNHC 141550
TWDEP 

TROPICAL WEATHER DISCUSSION      
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC FRI SEP 14 2007

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

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1530 UTC.

...TROPICAL WAVES...

TROPICAL WAVE ALONG 88W/89W FROM 8N THROUGH YUCATAN...MOVING W 
15-20 KT. MID LEVEL TURNING IS NOTED NEAR THE WAVE AXIS S OF 
GUATEMALA. AN MID/UPPER LEVEL TROUGH IS EVIDENT TO THE WEST 
ALONG 95W JUST WEST OF THE TEHUANTEPEC AREA...ENHANCING 
SCATTERED CONVECTION NEAR THE WAVE FROM 7N TO 11N BETWEEN 90W 
AND 94W.

TROPICAL WAVE ALONG 107W/108W S OF 17N MOVING W 5 KT. A 1008 MB 
LOW IS ALONG THE WAVE AXIS NEAR 11N BASED ON EARLIER QUIKSCAT 
AND ASCAT PASSES OVER THE SYSTEM. SCATTERED CONVECTION  PERSISTS 
ALONG THE ITCZ IN THE VICINITY OF THE WAVE AND LOW...AIDED BY 
MODERATE TO FRESH SWLY FLOW S OF THE ITCZ CONVERGING INTO THE 
LOW PRES AREA. TROPICAL CYCLONE DEVELOPMENT IS NOT ANTICIPATED 
OVER THE NEXT 48 HOURS ALTHOUGH THE LOW COULD GRADUALLY BECOME 
MORE ORGANIZED.

TROPICAL WAVE ALONG 137W/138W S OF 16N MOVING W 5 KT. A 1010 MB 
LOW IS ALONG THE WAVE AXIS NEAR 11N BASED ON ROTATION IN THE 
LOW/MID-LEVEL CLOUD FIELD ALONG THE ITCZ AXIS. BROKEN LOW/MID 
CLOUDS WITH ISOLATED SHOWERS FROM 10N-15N BETWEEN 134W-139W BUT 
WITH NO SIGNIFICANT CONVECTION NOTED.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 8N78W 12N102W 9N114W 11N125W 8N140W. 
SCATTERED MODERATE WITHIN 120 NM S OF AXIS ALONG THE PANAMANIAN 
AND COSTA RICAN COASTLINES BETWEEN 81W-84W. SCATTERED MODERATE 
WITHIN 120 NM OF AXIS BETWEEN 90W AND 95W. SCATTERED MODERATE 
WITHIN 120 NM OF AXIS BETWEEN 98W AND 111W. 

...DISCUSSION...

A MID/UPPER TROUGH ALONG 95W IS S OF A BROAD UPPER RIDGE THAT 
EXTENDS ACROSS CENTRAL MEXICO AND WELL OUT INTO THE EASTERN 
PACIFIC TO 12N130W. E OF THE MID/UPPER TROUGH IS ANOTHER UPPER 
RIDGE OVER THE SW CARIBBEAN. UPPER DIVERGENCE BETWEEN THESE IS 
ENHANCING CONVECTION ALONG THE ITCZ AND OFF THE COASTS OF 
SOUTHERN CENTRAL AMERICA. FURTHER W...ANOTHER BROADER UPPER 
TROUGH IS S OF THE UPPER RIDGE ALONG 120W...ADDING MODEST UPPER 
SUPPORT TO THE CONVECTION AROUND THE ITCZ WHERE IT INTERSECTS 
THE LOW/WAVE COMPLEX NEAR 108W. A SHARP UPPER TROUGH IS NOTED NW 
OF THE WRN EXTENT OF THE RIDGE NEAR 130W. SURFACE LOW IS 
CENTERED NEAR 1009 MB NEAR 17N114W WITH A TROUGH EXTENDING TO 
THE W TO 13N127W. DIFFLUENCE ALOFT BETWEEN THE UPPER RIDGE AND 
THE UPPER TROUGH TO THE W IS AIDING WEAK CONVECTION WITHIN 120 
NM N OF THE TROUGH AXIS. FORECAST FOR THE NEXT 48 HOURS WILL 
DEPEND MOSTLY ON THE POTENTIAL DEVELOPMENT OF VARIOUS LOW PRES 
CENTERS...MOSTLY ALONG THE ITCZ.  GLOBAL MODELS DIFFER GREATLY 
ON LOCATION AND INTENSITY HOWEVER...GIVEN THE DISORGANIZED 
FEATURES CURRENTLY ANALYZED. FOR MARINE INTERESTS...THE MAIN 
ISSUE WILL BE THE INTERACTION BETWEEN LOW PRES AREAS/TROPICAL 
WAVES AND HIGH PRES NW OF THE AREA...PRESENTING FRESH WINDS IN 
AN ARC FROM OFF THE BAJA PENINSULA TO N OF ITCZ GENERALLY W OF 
120W.

$$
CHRISTENSEN