000
AXPZ20 KNHC 032128
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC THU JUL 03 2008

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 
2100 UTC.

...SPECIAL FEATURES...

TROPICAL STORM BORIS CENTERED NEAR 17.3N 130.0W...OR 1180 NM WSW 
OF CABO SAN LUCAS MEXICO...AT 03/2100 UTC MOVING W AT 6 KT. 
MAXIMUM SUSTAINED WIND SPEED IS 35 KT WITH GUSTS TO 45 KT. 
ESTIMATED MINIMUM CENTRAL PRESSURE IS 1002 MB. SEE LATEST NHC 
FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP2/WTPZ22 KNHC 
FOR MORE DETAILS. BORIS HAS NOW MOVED OVER OCEAN WATER BETWEEN 
23-24C AND HAS SUBSEQUENTLY LOST MOST OF ITS CONVECTION THROUGH 
THE DAY. THE SYSTEM IS ALSO ENTRAINING INCREASINGLY MORE STABLE 
AIR...AND IT IS ULTIMATELY EXPECTED TO WEAKEN TO A DEPRESSION 
LATER THIS EVENING OR TONIGHT. SCATTERED SHOWERS/ISOLATED 
MODERATE CONVECTION WITHIN 210 NM NE QUADRANT. 

TROPICAL DEPRESSION DOUGLAS CENTERED NEAR 20.7N 110.6W...OR 140 
NM SSW OF CABO SAN LUCAS MEXICO...AT 03/2100 UTC MOVING NW AT 7 
KT. MAXIMUM SUSTAINED WIND SPEED IS 30 KT WITH GUSTS TO 40 KT. 
ESTIMATED MINIMUM CENTRAL PRESSURE IS 1004 MB. SEE LATEST NHC 
FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP4/WTPZ24 KNHC 
FOR MORE DETAILS. DOUGLAS HAS LOST ALL OF ITS DEEP CONVECTION AS 
IT MOVES OVER INCREASINGLY COOLER WATERS AND WILL DEGENERATE 
INTO A REMNANT LOW WITHIN THE NEXT 24 HRS. SCATTERED SHOWERS ARE 
WITHIN 240 NM S AND 120 NM N SEMICIRCLES.

A 1007 MB LOW IS LOCATED NEAR 12N96W...OR ABOUT 250 NM S OF 
PUERTO ANGEL MEXICO...MOVING WNW AT 5-10 KT. ALTHOUGH THE 
LOW-LEVEL CENTER APPEARS MORE WELL-DEFINED COMPARED TO 
YESTERDAY...THE SYSTEM HAS BEEN UNABLE TO GENERATE AN ORGANIZED 
AREA OF DEEP CONVECTION. THIS MAY BE DUE TO A MODEST INCREASE OF 
NORTHEASTERLY SHEAR FROM UPPER FLOW COMING FROM THE GULF COAST 
OF MEXICO. TWO DISTINCT CLUSTERS LIE TO THE N AND SW OF THE 
CENTER. SCATTERED MODERATE/ISOLATED STRONG CONVECTION FROM 
11N-15N BETWEEN 90W-99W. SCATTERED MODERATE FROM 06N-10N BETWEEN 
94W-105W. TROPICAL CYCLONE DEVELOPMENT IS STILL POSSIBLE WITHIN 
THE SYSTEM WITHIN THE NEXT 48 HOURS AS IT MOVES NW OFF THE 
SOUTHERN COAST OF MEXICO.

...TROPICAL WAVES...

TROPICAL WAVE JUST OFF THE COAST OF COLOMBIA ALONG 78W/79W N OF 
02N MOVING W 10-15 KT. THE WAVE IS NOT VERY WELL-DEFINED BUT IS 
NEAR AN INCREASE IN CONVECTION OVER THE SW CARIBBEAN. SCATTERED 
MODERATE N OF 06N ACROSS PANAMA E OF 81W.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 08N77W TO 06N82W TO 11N95W TO 
09N103W TO 15N121W TO 07N134W TO 07N140W. SCATTERED MODERATE 
CONVECTION FROM 03N-10N BETWEEN 78W-92W. SCATTERED MODERATE 
WITHIN 45 NM OF AXIS BETWEEN 127W-132W.
 
...DISCUSSION...

SUBTROPICS...
A SHARP UPPER LEVEL TROUGH CONTINUES TO LIE W OF THE CALIFORNIA 
COAST AND EXTENDS INTO THE AREA FROM 30N134W TO 26N140W. THE 
TROUGH HAS BEEN SENDING SEVERAL WAVES OF FRONTAL BOUNDARIES INTO 
THE NW PART OF THE REGION BUT THEY HAVE BEEN QUICKLY WASHING OUT 
AS THE SUBTROPICAL RIDGE HOLDS TOUGH. ONE FRONT NOW EXTENDS FROM 
30N133W TO 26N140W WHILE A SECOND LIES JUST NW OF THE AREA AND 
SHOULD CROSS 30N140W OVERNIGHT. LIMITED MOISTURE WILL ONLY 
PRODUCE ISOLATED SHOWERS...ESPECIALLY NEAR THE SECOND BOUNDARY. 
OTHERWISE...THE UPPER TROUGH IS PULLING MOISTURE FROM T.S. BORIS 
NWD INTO A THIN RIBBON OF CIRRUS EXTENDING FROM 20N130W N THEN 
NE TOWARDS SOUTHERN CALIFORNIA. TO THE E...A STRONG UPPER HIGH 
IS LOCATED W OF BAJA CALIFORNIA NEAR 27N120W AND IS PRODUCING 
MODERATE/STRONG SUBSIDENCE E OF 125W TO THE COAST. NORTHWESTERLY 
FLOW ALOFT COVERS NE MEXICO DUE TO A TROUGH OVER THE GULF OF 
MEXICO AND DEEP-LAYERED MOISTURE VALUES ARE SUFFICIENT ENOUGH 
FOR SCATTERED TSTMS TO DEVELOP OVER MOST OF MEXICO.

TROPICS...
DEEP EASTERLY FLOW COVERS MUCH OF THE TROPICS BETWEEN COLOMBIA 
AND 105W AND IS COINCIDENT WITH FAIRLY HIGH PRECIPITABLE WATER 
VALUES. FARTHER W...A WEAK UPPER LOW IS LOCATED SW OF T.D. 
DOUGLAS NEAR 15N115W AND THIS IS CAUSING THE FLOW TO TURN 
SOUTHEASTERLY TOWARDS SOCORRO ISLAND WHILE AN ASSOCIATED 
INVERTED TROUGH EXTENDS FROM THE LOW SWD TO 03N116W. THIS LINE 
MARKS THE WESTERN EDGE OF THE DEEPEST MOISTURE. THE UPPER FLOW 
IS MAINLY SE TO SOUTHERLY OVER THE AREA W OF 125W DUE TO THE 
UPPER TROUGH OVER THE SUBTROPICAL WATERS AND A DYING TROUGH AXIS 
FROM 23N137W TO 07N145W. THE ITCZ IS BEGINNING TO RECONSTITUTE 
ITSELF NOW THAT T.S. BORIS AND DOUGLAS ARE MOVING FARTHER N AND 
W OVER THE SUBTROPICAL WATERS.

$$
BERG