000
AXPZ20 KNHC 060320
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC WED SEP 06 2006

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W. THE FOLLOWING INFORMATION IS 
BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND 
METEOROLOGICAL ANALYSIS.

BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0300 UTC.

...SPECIAL FEATURES...
TROPICAL STORM KRISTY WAS LOCATED NEAR 17.1N 123.9W AT 06/0300 
UTC MOVING WNW OR 285 DEG AT 11 KT. MAXIMUM SUSTAINED WINDS HAVE 
DECREASED TO 35 KT WITH GUSTS TO 45 KT. ESTIMATED MINIMUM 
CENTRAL PRESSURE IS 1004 MB. CONVECTION NEAR THE CENTER OF THE 
STORM HAS DECREASED IN COVERAGE SOMEWHAT AND ALSO WARMED 
SLIGHTLY INDICATING THAT SOME OF THE STABLE AIR SURROUNDING THE 
STORM MAY BE ENTRAINING INTO THE CIRCULATION. IN ANY EVENT SOME 
STRENGTHENING IS POSSIBLE OVER THE NEXT 24 HOURS AS KRISTY 
TRACKS W UNDER AN UPPER RIDGE WITH LITTLE CHANGE EXPECTED IN 
SHEAR OR SEA SURFACE TEMPERATURES. SEE LATEST NHC 
FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP2/WTPZ22 KNHC 
FOR MORE DETAILS. 

...TROPICAL WAVES...
.NONE

...INTERTROPICAL CONVERGENCE ZONE...AXIS 9N84W 11N100W 11N120W 
7N140W. SCATTERED MODERATE ISOLATED STRONG WITHIN 120 NM S OF 
THE AXIS BETWEEN 108W AND 111W. SCATTERED MODERATE WITHIN 120 NM 
OF AXIS BETWEEN 128W AND 136W. 

...DISCUSSION...

THE CENTRAL PACIFIC IS DOMINATED BY A LONG WAVE TROUGH WITH MEAN 
AXIS ALONG 155-160W. SEVERAL SHORTWAVES ARE ROTATING THROUGH THE 
BASE OF THE TROUGH. THE FIRST SHORTWAVE HAS LIFTED WELL NW OF 
THE AREA WHILE A SECOND AND MORE VIGOROUS UPPER TROUGH IS 
APPROACHING THE NW PORTION OF THE DISCUSSION AREA AND EXTENDS 
FROM A WELL DEFINED CYCLONIC CIRCULATION NEAR 31N149W SWWD TO 
NEAR 24N151W. THIS SHORTWAVE AND ASSOCIATED CYCLONIC CIRCULATION 
ARE RIDING NEWD AT 15-20 KT OVER A WWD EXPANDING RIDGE WHICH 
EXTENDS FROM AN ANTICYCLONE NEAR 28N125W SWWD TO 22N142W. 

ANOTHER UPPER ANTICYCLONE IS NEAR 25N109W WITH A RIDGE EXTENDING 
W ACROSS OLD MEXICO AND THE BAJA PENINSULA ALONG 26N TO THE 
ANTICYCLONE NOTED ABOVE. YET ANOTHER SMALL ANTICYCLONE IS NEAR 
20N105W RIDGING S OVER THE E PACIFIC. ITS ENVELOPE OF 
ANTICYCLONIC FLOW DOMINATES THE UPPER LEVELS N OF 10N BETWEEN 
90W AND 105W. IN ADDITION THIS FLOW WAS ADVECTING MOISTURE FROM 
CONVECTION OVER THE NW CARIBBEAN AND SOUTHERN GULF OF MEXICO 
SWWD AND COMBINED WITH THE CONVECTION ALONG THE MEXICAN COAST 
FROM 19N TO 23N AND ITCZ CONVECTION RESULTING IN MOIST UPPER 
LEVELS IN THE TROPICS N OF THE ITCZ TO THE E OF 105W.

THE UPPER LEVELS S OF 18N W OF 105W ARE DOMINATED BY EASTERLY 
WINDS TO THE SOUTH OF THE RIDGE NOTED ABOVE. THIS FLOW WAS 
ADVECTING UPPER LEVEL MOISTURE WWD TO 140W AND SPLIT AN AREA OF 
STRONG SUBSIDENCE IN HALF...CONFINING THE VERY DRY AIR TO AN 
AREA N OF 27N E OF 130W. 

A LOW LEVEL RIDGE EXTENDS INTO THE NW PORTION ALONG 32N132W 
24N122W. 
 
$$
COBB