000
AXPZ20 KNHC 281607
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC THU FEB 28 2008

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 
1530 UTC.
 
...ITCZ...

ITCZ-RELATED AXIS CENTERED ALONG 05N78W TO 04N84W TO 04N100W TO
07N114W TO 06N127W TO 04140W. SCATTERED MODERATE CONVECTION IS 
WITHIN 30 NM OF THE AXIS BETWEEN 86W-89W.

SCATTERED MODERATE CONVECTION IS WITHIN 30 NM OF 06N79W. 

...DISCUSSION...

A NEGATIVELY-TILT DEEP LAYERED TROUGH EXTENDS FROM SRN CALIFORNIA
SW TO AN UPPER LEVEL CYCLONE MOVING SE 15-20 KT NEAR 28N128.5W.
THE TROUGH THEN CONTINUES SW 23N134W WHERE IT BECOMES MORE OF
A MID/UPPER LEVEL SHEAR AXIS TO SW OF THE REGION AT 21N140W.
A MID-LEVEL RIDGE IS LOCATED AHEAD OF THE TROUGH FROM NEAR NRN
BAJA S TO 25N118W TO 18N118W...AND TO A MID/UPPER LEVEL 
ANTICYCLONE NEAR 12N117W. WEAK MID/UPPER LEVEL TROUGH IS OVER
THE GULF OF CALIFORNIA EXTENDING SW TO NEAR15N112W...AND WILL 
MOVE INTO WRN MEXICO LATER TODAY. BROAD UPPER LEVEL RIDGING 
COVERS THE AREA S OF 28N BETWEEN 110W-126W. MODELS FORECAST THE 
RIDGE TO SLIDE EWD THROUGH THE NEXT 18-24HRS ALLOWING THE TROUGH 
ADVANCING TO E OF THE AREA AND WEAKEN OVER NRN MEXICO IN ABOUT 
36-48 HRS.

TO THE W OF THE TROUGH...A MID/UPPER LEVEL RIDGE STRETCHES FROM 
24N139W NEWD THROUGH 28N138W AND NE OF THE AREA AT 32N137W. DEEP 
CENTRAL TROPICAL PACIFIC UPPER LEVEL MOISTURE IS CHANNELED NEWD 
ACROSS THE RIDGE TO WELL NW OF THE REGION...BUT THEN SPREADS SSE 
INTO THE AREA ON THE E SIDE OF THE RIDGE INTO THE WAKE OF THE 
TROUGH N OF 24N AND W OF 134W. CONFLUENT FLOW INTO THE IMMEDIATE 
BACK SIDE OF THE RIDGE IS RESULTING IN MODERATE SUBSIDENCE 
WITHIN 60 NM EITHER SIDE OF A LINE FROM 24N132W TO 28N133W AND 
NE AT 32N131W. OTHER MODERATE SUBSIDENCE IS NOTED ON WATER VAPOR 
IMAGERY FROM 20N-24N AND W OF 132W. A MID/UPPER LEVEL TROUGH IS 
LOCATED JUST W OF THE REGION EXTENDING ROUGHLY FROM 21N142W TO 
14N145W.

MID TO UPPER LEVEL RIDGING IS PRESENT TO THE SE OF THE TROUGH E 
OF 90W TO INCLUDE CENTRAL AMERICA AND THE FAR ERN PACIFIC 
WATERS. ONLY ISOLATED WEAK CONVECTION IS NOTED IN THOSE AREAS.

MODERATE SUBSIDENCE UNDER BROAD UPPER RIDGING IS OCCURRING S OF
9N BETWEEN 90W-120W.

AT THE SURFACE...A DISSIPATING 1025 MB HIGH IS ANALYZED NEAR 
32N136.5W WITH A RIDGE SE TO 21N122W. HIGH PRES COVERS THE AREA 
N OF 15N AND W OF 120W. PRES ANALYSIS INDICATES BROAD TROUGHING 
PRESENT OVER BAJA CALIFORNIA AND VICINITY WITH A 1010 MB LOW
NEAR 31N114W.

GAP WINDS...A HIGH RESOLUTION ASCAT PASS FROM LAST NIGHT 
REVEALED 30-40 KT IN THE GULF OF TEHUANTEPEC. LATEST MODEL 
GUIDANCE SUGGESTS THESE WINDS TO CONTINUE TO DIMINISH TO
LESS THAN GALE FORCE IN ABOUT 12 HRS.

GULF OF PANAMA AND PAPAGAYO...A QUIKSCAT PASS FROM 1122 UTC
THIS MORNING SHOWED N-NE WINDS OF 15-20 KT THROUGH THE GULFS OF 
PAPAGAYO AND PANAMA WITH WINDS EXPECTED TO INCREASE UP 25 KT
THROUGH IN THE GULF OF PAPAGAYO IN 24-48 HRS.

$$
AGUIRRE