000
AXPZ20 KNHC 012222
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2232 UTC MON OCT 01 2007

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 
1215 UTC.
  
...SPECIAL FEATURE...

TROPICAL STORM JULIETTE CENTERED NEAR 22.7N 115.5W AT 01/2100 
UTC MOVING NNW OR 335 DEGREES AT 8 KT. ESTIMATED MINIMUM CENTRAL 
PRESSURE IS 1004 MB. MAXIMUM SUSTAINED WIND SPEED IS 35 KT GUSTS 
TO 40 KT. SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO 
HEADERS MIATCMEP4/ WTPZ24 KNHC FOR MORE DETAILS. JULIETTE IS 
EXPERIENCING STRONG SLY SHEAR...KEEPING CONVECTION WELL TO THE 
NORTH. IN ADDITION...AS THE STORM MOVES FURTHER INTO COOLER 
WATER AND MORE STABLE AIR...THE CONVECTION IS SUBSIDING. AS A 
RESULT...THE STORM IS EXPECTED TO WEAKEN BELOW TROPICAL STORM 
STRENGTH BY TONIGHT AND BECOME A DEPRESSION.

...TROPICAL WAVES...

TROPICAL WAVE ALONG 93W N OF 5N MOVING W 10 KT. LOW LEVEL 
CYCLONIC TURNING IS BEING ENHANCED BY 20 TO 25 KT FLOW THROUGH 
THE GULF OF TEHUANTEPEC. NO SIGNIFICANT CONVECTION IS NOTED. 

WEAK TROPICAL WAVE ALONG 134W MOVING W 10 TO 15 KT. WEAK 
CYCLONIC ROTATION NOTED WHERE THE WAVE INTERSECTS THE ITCZ. NO 
CONVECTION NOTED.

...ITCZ...

INTERTROPICAL CONVERGENCE ZONE...AXIS ALONG 11N86W 9N100W 
15N110W 15N119W 10N127W 10N140W. SCATTERED MODERATE CONVECTION 
WITHIN 120 NM OF AXIS BETWEEN 107W AND 109W. 

...DISCUSSION...

EAST OF 120W...
MAIN WEATHER INFLUENCE IS A BROAD UPPER ANTICYCLONE CENTERED 
OVER N CENTRAL MEXICO. THIS IS PROVIDING MODERATE TO STRONG 
SHEAR ACROSS THE ITCZ W OF 95W. AN UPPER LOW IS CENTERED E OF 
THE UPPER ANTICYCLONE OVER THE YUCATAN CHANNEL. NELY FLOW ALOFT 
BETWEEN THESE FEATURES IS BRINGING DRIER AND MORE STABLE AIR 
INTO AREA ALONG THE ITCZ E OF 95W...SUPPRESSING CONVECTION FOR 
THE MOST PART. FRESH NLY FLOW IS EVIDENT IN LAND BASED SURFACE 
OBSERVATIONS THROUGH GULF OF TEHUANTEPEC...THE RESULT OF HIGHER 
DENSITY AIR OVER THE GULF OF MEXICO FUNNELING THROUGH THE 
ISTHMUS. THIS WILL GRADUALLY ABATE OVER THE NEXT 36 HOURS OR SO.

W OF 120W...
UPPER TROUGH EXTENDS FROM 30N120W TO 16N130W...BRINGING DRY AND 
STABLE AIR OVER MUCH OF THE AREA AND SUPPRESSING CONVECTIVE 
DEVELOPMENT. AT THE SURFACE...MODERATE TO FRESH TRADE WIND FLOW 
ON THE PERIPHERY OF HIGH PRES CENTERED OVER THE CENTRAL PACIFIC 
IS EVIDENT ON SCATTEROMETER AND SHIP OBSERVATIONS. LITTLE CHANGE 
IS EXPECTED OVER THE NEXT 48 HOURS.

$$
CHRISTENSEN