000
AXPZ20 KNHC 030335
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC THU JUL 03 2008

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

BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0315 UTC.

...SPECIAL FEATURES...

TROPICAL STORM BORIS IS CENTERED NEAR 17.7N 128.3W...OR 1080 NM 
WSW OF CABO SAN LUCAS MEXICO...AT 03/0300 UTC MOVING NW AT 7 KT. 
MAXIMUM SUSTAINED WIND SPEED IS 50 KT WITH GUSTS TO 60 KT. 
ESTIMATED MINIMUM CENTRAL PRESSURE IS 995 MB. SEE LATEST NHC 
FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP2/WTPZ22 KNHC 
FOR MORE DETAILS. ALTHOUGH THE EYE HAS FILLED IN...A WARM SPOT 
IS STILL NOTED IN THE MIDDLE OF THE CONVECTIVE CANOPY NEAR THE 
LOW-LEVEL CENTER AS DEEP CONVECTION CONTINUES TO DEVELOP IN A 30 
NM RADIUS RING. UPPER LEVEL OUTFLOW IS EXCELLENT OVER THE N 
QUADRANT WHERE THE FLOW IS BEING ENTRAINED INTO AN UPPER TROUGH 
ALONG 135W AND THE VERTICAL SHEAR IS QUITE LOW AT THE 
MOMENT...ABOUT 5-10 KT OUT OF THE SE. BORIS IS OVER 24-25C WATER 
AND IS MOVING INTO A MORE STABLE ENVIRONMENT SO CONTINUED 
WEAKENING IS EXPECTED OVER THE NEXT 24-48 HOURS. SCATTERED 
MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 120 NM N AND 90 NM 
S SEMICIRCLES.

TROPICAL STORM DOUGLAS IS CENTERED NEAR 18.8N 109.1W...OR 250 NM 
S OF CABO SAN LUCAS MEXICO AND 275 W OF MANZANILLO MEXICO...AT 
03/0300 UTC MOVING NW AT 8 KT. MAXIMUM SUSTAINED WIND SPEED IS 
35 KT WITH GUSTS TO 45 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 
1004 MB. SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO 
HEADERS MIATCMEP4/WTPZ24 KNHC FOR MORE DETAILS. 20-25 KT OF 
EAST-NORTHEASTERLY SHEAR CONTINUES TO HAMPER THE DEVELOPMENT OF 
DOUGLAS WITH THE LOW-LEVEL CENTER PARTIALLY EXPOSED ON THE N 
SIDE OF THE DEEP CONVECTION. SCATTERED MODERATE CONVECTION IS 
WITHIN 240 NM SW AND 60 NM NE SEMICIRCLES. ONLY SLIGHT 
STRENGTHENING IS EXPECTED IN THE NEXT 12-24 HRS BEFORE DOUGLAS 
REACHES COOLER WATERS OFF THE COAST OF BAJA CALIFORNIA.

A 1007 MB LOW IS LOCATED NEAR 11N94W...OR ABOUT 345 NM SSE OF 
PUERTO ANGEL MEXICO...MOVING NW AT 6 KT. THE LOW IS ASSOCIATED 
WITH A TROPICAL WAVE WHICH HAS BEEN MOVING W ACROSS CENTRAL 
AMERICA OVER THE PAST COUPLE OF DAYS. DEEP CONVECTION HAS 
VIRTUALLY VANISHED FROM EARLIER IN THE DAY BUT IT IS LIKELY THAT 
NEW ACTIVITY WILL DEVELOP LATER TONIGHT OR TOMORROW. SCATTERED 
SHOWERS/ISOLATED TSTMS FROM 05N-14N BETWEEN 90W-100W. TROPICAL 
CYCLONE DEVELOPMENT IS STILL POSSIBLE WITHIN THE NEXT 48 HRS AS 
THE SYSTEM MOVES SLOWLY NW OFF THE SOUTHERN COAST OF MEXICO.

...TROPICAL WAVES...

SEE SPECIAL FEATURES FOR TROPICAL WAVE AND ASSOCIATED LOW ALONG 
94W.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 08N77W TO 10N94W TO 06N117W THEN 
FROM 14N123W TO 07N140W. SCATTERED MODERATE ISOLATED STRONG N OF 
03N BETWEEN 82W AND 88W.
 
...DISCUSSION...

SUBTROPICS...
A SHARP UPPER LEVEL TROUGH IS LOCATED OFF THE W COAST OF THE 
UNITED STATES...WITH THE AXIS EXTENDING FROM AN UPPER LOW NEAR 
44N133W TO 30N136W TO 20N140W. 30-40 KT UPPER LEVEL W/SW WINDS 
CURVE AROUND THE BASE OF THE TROUGH N OF 27N W OF 125W AND SOME 
UPPER LEVEL CIRRUS IS PLUNGING SE INTO THE AREA ON THE W SIDE OF 
THE TROUGH. THE TROUGH IS CAUSING TROPICAL STORM BORIS TO MOVE 
TOWARDS THE NW DUE TO THE DEEP-LAYERED FLOW COMING OUT OF THE 
SE. FARTHER E...AN UPPER HIGH IS CENTERED W OF BAJA CALIFORNIA 
NEAR 26N120W WHILE A SMALL UPPER LOW IS EMBEDDED WITHIN ITS 
CIRCULATION NEAR 21N120W. MODERATE/STRONG SUBSIDENCE LIES N OF 
20N BETWEEN 112W-125W WITH BROKEN STRATOCUMULUS COVERING THE 
AREA. THE RIDGE ASSOCIATED WITH THE HIGH COVERS MUCH OF WESTERN 
MEXICO BUT THEN THE FLOW OVER THE EASTERN HALF OF THE COUNTRY 
TURNS OUT OF THE NW INTO A DEEP TROUGH OVER THE GULF OF MEXICO. 
SCATTERED TSTMS ARE LOCATED OVER THE SIERRA MADRES AND THE 
MEXICAN PLATEAU.

TROPICS...
WATER VAPOR IMAGERY SHOWS THAT DEEP MOISTURE EXTENDS ACROSS THE 
ENTIRE TROPICAL REGIME E OF 120W AS WELL AS IN THE VICINITY OF 
T.S. BORIS NEAR 18N128W. UPPER LEVEL WINDS ARE PRIMARILY 
EASTERLY S OF 10N BUT ARE MORE VARIABLE FROM 10N-20N DUE TO THE 
OUTFLOW AROUND T.S. BORIS AND T.S. DOUGLAS. CIMSS WIND ANALYSES 
INDICATE THAT HIGH SHEAR VALUES ARE MAINLY CONFINED BETWEEN 
100W-125W...ESPECIALLY DUE TO AN OUTFLOW JET SW OF DOUGLAS. 
ELSEWHERE...BROAD UPPER LEVEL DIVERGENCE LIES E OF 100W AND WAS 
ENHANCING CONVECTION NEAR THE SURFACE LOW S OF THE GULF OF 
TEHUANTEPEC. A COL REGION LIES W OF 130W WHERE THE BASE OF THE 
MID-LATITUDE TROUGH MEETS THE DEEP-LAYERED TROPICAL EASTERLIES. 
THIS IS PRODUCING STRONG SUBSIDENCE W OF 133W IN ADVANCE OF T.S. 
BORIS.

$$
BERG