000
AXPZ20 KNHC 021556
TWDEP 

TROPICAL WEATHER DISCUSSION     
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC SUN SEP 02 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 
1445 UTC.

...SPECIAL FEATURES...

TROPICAL STORM HENRIETTE CENTERED NEAR 18.8N 106.7W AT 02/1500 
UTC. HENRIETTE IS MOVING W NW AT 6 KT. MAXIMUM SUSTAINED WINDS 
ARE NEAR 70 MPH WITH HIGHER GUSTS. HENRIETTE WILL MOVE INTO AN 
IDEAL ENVIRONMENT FOR STRENGTHENING DURING THE NEXT 36-48 HOURS. 
THE UPPER LEVEL OUTFLOW IS UNRESTRICTED ALOFT WITH THE 
ANTICYCLONE OVER HENRIETTE FORECAST TO BECOMING BETTER DEFINED 
DURING THE NEW FEW DAYS. ADDITIONALLY SURFACE WATERS 
TEMPERATURES ARE WARM. HENRIETTE IS FORECAST TO BECOME A 
HURRICANE LATER TODAY. ESTIMATED CENTRAL PRESSURE IS 994 MB. 
CURRENTLY...NUMEROUS MODERATE AND STRONG CONVECTION IS OBSERVED 
WITHIN 90 NM OVER THE NW SEMICIRCLE AND WITHIN 300 NM OVER THE 
SE SEMICIRCLE WITH ANOTHER BAND NOTED WELL SE OF THE CENTER NEAR 
14N103W. REFER TO THE LATEST NHC FORECAST/ADVISORY UNDER 
AWIPS/WMO HEADERS MIATCMEP1/WTPZ21 KNHC FOR MORE DETAILS.

TROPICAL DEPRESSION GIL IS CENTERED NEAR 19.7N 124.0W AT 
02/1500Z UTC MOVING W NW AT 7 KT. MAXIMUM SUSTAINED WIND SPEED 
IS 20 KT WITH GUSTS TO 25 KT MOSTLY IN THE NW QUADRANT AND 
ASSOCIATED WITH THE PRES GRADIENT DUE TO THE RIDGE TO THE N. 
ESTIMATED MINIMUM CENTRAL PRESSURE IS 1007 MB. ALL DEEP 
CONVECTION ASSOCIATED WITH GIL HAS DISSIPATED EXCEPT FOR A SMALL 
CLUSTER OF TSTM ACTIVITY LOCATED WELL W OF THE EXPOSED CENTER. 
NHC HAS WRITTEN THE FINAL ADVISORY ON THIS SYSTEM AND THE 
REMNANT LOW OF GIL SHOULD PERSIST ANOTHER DAY OR SO...THEN 
BECOME INDISTINGUISHABLE...EMBEDDED WITHIN THE LARGE SCALE FLOW 
WEST OF TROPICAL STORM HENRIETTE. SEE THE LAST NHC FORECAST/ 
ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP5/WTPZ25 KNHC FOR MORE 
DETAILS.


...TROPICAL WAVES...

TROPICAL WAVE ALONG 92.5W MOVING W ABOUT 12 KT. ONLY WEAK 
CYCLONIC TURNING AND A FEW TSTMS ARE NOTED NEAR 10N92W.

TROPICAL WAVE ALONG 82W IS ESTIMATED TO BE MOVING W AT 15 KT. 
ONLY SCATTERED MODERATE CONVECTION IS NOTED N OF 3N E OF 85W.

...ITCZ...

AXIS CENTERED ALONG 8N84W 11N95W 18N115W 10N140W. EXCEPT AS 
MENTIONED WITH THE TROPICAL WAVES...SCATTERED MODERATE IS NOTED 
NEAR 8N96W.

...DISCUSSION...

AN UPPER ANTICYCLONE AT 33N120W RIDGES SW TO A SHARP CREST AT 
24N137W. VERY DRY UPPER AIR IS INDICATED TO THE NW OF THIS RIDGE 
LINE. AN UPPER TROUGH LIES ROUGHLY ALONG 10N136W 20N128W 25N114W 
EFFECTIVELY SEPARATING THE ANTICYCLONIC FLOW ASSOCIATED THE 
AFOREMENTIONED RIDGE FROM THE INCREASING ANTICYCLONIC FLOW 
ASSOCIATED WITH THE UPPER RIDGE OVER CYCLONE HENRIETTE. RAPIDLY 
DISSIPATING TROPICAL DEPRESSION GIL LIES UNDER THE UPPER TROUGH 
WITH JUST ENOUGH ELY SHEAR TO EXPOSE ITS LOW LEVEL CENTER... 
WITH THE DEBRIS MOISTURE TRAPPED WITHIN 60 NM EITHER SIDE OF 
LINE 21N120W 21N128W. OTHERWISE DRY UPPER AIR IS ALSO NOTED S OF 
THE UPPER RIDGE W OF 120W AND SUPPRESSES CONVECTION ALONG THE 
ITCZ W OF 114W.
    
THE UPPER VENTILATION OVER HENRIETTE IS EXPANDING AND COVERS THE 
DISCUSSION AREA S OF 24N BETWEEN 90W AND 113W WITH THE UPPER 
DEBRIS MOISTURE FROM THE HURRICANE TRAPPED WITHIN THE SAME AREA. 
THE UPPER FLOW IS NE TO E OVER THE DEEP TROPICAL PAC E OF 90W.
   
$$
NELSON