000
AXPZ20 KNHC 080324
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC THU NOV 08 2007

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 
0300 UTC.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 8N77W 10N84W 8N100W 12N120W 9N140W. 
SCATTERED MODERATE CONVECTION WITHIN 45 NM OF AXIS BETWEEN 
94W-99W. NUMEROUS MODERATE/STRONG WITHIN 75 NM OF AXIS W OF 127W.

...DISCUSSION...

E OF 115W...
AN EXPANSIVE MID/UPPER LEVEL HIGH REMAINS ENTRENCHED OVER 
S/CENTRAL MEXICO WITH THE ASSOCIATED RIDGE AXIS EXTENDING FROM 
THE GULF OF HONDURAS NW ACROSS NW MEXICO INTO ARIZONA AND NEW 
MEXICO. ANTICYCLONIC UPPER LEVEL FLOW EXTENDS AS FAR W AS 120W N 
OF 15N AND BROKEN CIRRUS IS ROTATING FROM THE E PACIFIC WATERS N 
AND NEWD ACROSS BAJA CALIFORNIA AND NW MEXICO. DEEP EASTERLY 
FLOW LIES ACROSS THE PACIFIC WATERS E OF 100W BUT THEN BECOMES 
SOUTHEASTERLY W OF 100W...AND WEAK UPPER DIFFLUENCE WHERE THE 
FLOW TURNS IS ENHANCING TSTM ACTIVITY ALONG THE ITCZ BETWEEN 
95W-103W. THIS ACTIVITY ALSO APPEARS TO BE OCCURRING DUE TO 
STRONG LOW-LEVEL CONVERGENCE ASSOCIATED WITH THE NORTHERLY SURGE 
COMING FROM THE GULF OF TEHUANTEPEC. ELSEWHERE...THE ITCZ AND A 
DECAYING FRONTAL BOUNDARY OVER THE FAR SW CARIBBEAN ARE BOTH 
PRODUCING SCATTERED SHOWERS OVER PORTIONS OF SRN NICARAGUA... 
COSTA RICA...AND PANAMA.

AN EVENING QUIKSCAT PASS CONFIRMS THAT WINDS OVER THE GULF OF 
TEHUANTEPEC ARE HOLDING STEADY AT GALE FORCE TO ABOUT 40 KT. 
MODEL GUIDANCE CONTINUES THE GALE FOR ANOTHER 36 HRS OR SO WITH 
WINDS DROPPING BELOW WARNING CRITERIA BY FRI MORNING. THIS IS A 
LITTLE LATER THAN PREVIOUSLY THOUGHT. ALSO...GFS GUIDANCE 
APPEARS TO BE OVERDOING THE AREAL COVERAGE OF THE WIND FIELD 
JUST W OF NICARAGUA. UNFORTUNATELY IT SEEMS TO STRUGGLE WITH 
GULF OF PAPAGAYO/FONSECA GAP WIND EVENTS...UNLIKE ITS GOOD 
PERFORMANCE WITH TEHUANTEPEC EVENTS.

W OF 115W...
THE MID/UPPER LEVEL CUT-OFF LOW WHICH HAS BEEN OFF THE 
CALIFORNIA COAST HAS DRIFTED SWD SINCE YESTERDAY...NOW W OF LOS 
ANGELES NEAR 33N128W. BROAD TROUGHING LIES S OF THE LOW AND 
COVERS THE REGION N OF 15N W OF 115W WITH A NEARLY CUT-OFF 
TROUGH AXIS EXTENDING FROM 28N131W TO 21N136W. A BROKEN 
STRATOCUMULUS FIELD LIES N OF 22N BETWEEN THE BAJA COAST AND 
132W...AND SOME COASTAL STRATUS IS BANKED ALONG THE BAJA COAST 
PRIMARILY N OF 28N. ANOTHER UPPER TROUGH EXTENDS SE OF THE BROAD 
TROUGH FROM 20N122W TO 10N115W. FARTHER S...THE UPPER FLOW S OF 
12N TURNS NORTHERLY TOWARDS THE EQUATOR...AND THE RESULTANT 
DIFFLUENCE BETWEEN IT AND THE FLOW AROUND THE TROUGH IS 
PRODUCING SCATTERED MODERATE CONVECTION ALONG THE ITCZ W OF 126W.

$$
BERG