000
AXPZ20 KNHC 260914
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC FRI OCT 26 2007

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

BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 0845 UTC.

...ITCZ....
AXIS ALONG 9N78W 10N86W 8N96W 11N105W 9N111W 11N121W 9N140W. 
SCATTERED MODERATE CONVECTION NEAR 8N83W 10N101W 11N105W 16N105W 
AND 9N135W. 

ISOLATED MODERATE NEAR 20.5N122W.

...DISCUSSION...

A MID LEVEL TROUGH IS WORKING IT'S WAY INTO OUR REGION TONIGHT 
WITH HELP FROM A SHARP UPPER RIDGE ALONG 140W NEAR 40N. ON OLD 
MID LEVEL CYCLONIC CIRCULATION..POSSIBLY THE REMNANT OF KIKO WAS 
LOCATED NEAR 23N127W IN WATER VAPOR IMAGERY DRIFTING NNE. IT HAS 
BEEN EMBEDDED IN A LARGE MID LEVEL RIDGE THE PAST FEW DAYS BUT 
IS BEGINNING TO FEEL THE APPROACH OF THE TROUGH MENTIONED ABOVE. 
ON THE SURFACE TONIGHT A FAIRLY STRONG PACIFIC RIDGE SITUATED 
MOSTLY NW OF THE REGION BUT WITH ENOUGH GRADIENT N OF 24N W OF 
126W TO PRODUCE NE WINDS 25 TO 30 KT. SSMI CONFIRMS THESE SPEEDS 
WHILE QUIKSCAT PASS MISSED THE STRONGEST PORTION. WINDS THROUGH 
TEHUANTEPEC HAVE DECREASED BELOW GALE FORCE AS PRES GRADIENT 
OVER THE SW GULF HAS DIMINISHED. ELSEWHERE GAP WINDS ARE LIGHT. 
WINDS ALONG THE BAJA COAST MOSTLY NWLY 5 TO 10 KT. CROSS 
EQUATORIAL WINDS TO 20 KT BETWEEN 95W AND 105W AND BETWEEN 118W 
AND 130W ACCORDING TO SSMI. 

LATER DAY 1 THE UPPER TROUGH WITH A GOOD NLY JET ON IT'S W SIDE 
WILL CONTINUE SEWD AND CAPTURE THE EMBEDDED CYCLONIC CENTER 
MENTIONED ABOVE. IN THE MEANTIME THE MID LEVEL RIDGE OVER MEXICO 
AND BAJA BEGINS TO STRENGTHEN WITH APPROACH OF THE LARGE TROUGH 
SYSTEM TO THE W. ON THE SURFACE LATER DAY 1 LITTLE CHANGE 
OVERALL. STILL SOME OCCASIONAL GUSTY WINDS TO 20 KT THROUGH 
TEHUANTEPEC AS A WEAK NLY FLOW PERSISTS OVER THE BAY OF 
CAMPECHE. CROSS EQUATORIAL WINDS S OF 5N E OF 100W OCCASIONALLY 
TO 20 KT WITH S SWELL TO 8 FT. S OF 7N W OF 115W SE WINDS TO 20 
KT WITH SIMILAR SLY SWELL.

FOR DAY 2 GFS MODEL SHOWS THE FAIRLY STRONG UPPER TROUGH MERGING 
WITH THE OLD CYCLONIC CIRCULATION AND CLOSING OFF NEAR 33N133W 
WITH A SECONDARY ENERGY CENTER ROTATING AROUND THE S SIDE NEAR 
23N137W. THE MID LEVEL RIDGE OVER NW MEXICO AND BAJA HOLDS IT'S 
OWN AND WILL BLOCK THE EWD MOVEMENT OF THE UPPER TROUGH. ON THE 
SURFACE DAY 2 LOOK FOR HIGH PRES OVER THE WRN GULF OF MEXICO TO 
STRENGTHEN WITH SUPPORT FROM THE BLOCKING RIDGE ALOFT. THUS 
WINDS INCREASE THROUGH TEHUANTEPEC WITH POSSIBLE GALE CONDITIONS 
DEVELOPING. FURTHER NW..THE PACIFIC RIDGE RECEDES WWD AS A 
SURFACE TROUGH DEVELOPS ALONG 130W. THE TROUGH IS A RESULT OF 
THE STRONG TROUGH ALOFT CLOSING OFF. SURFACE WINDS N OF 20N W OF 
135W WILL REMAIN N TO NE AT 20 TO 25 KT WITH NLY SWELL 12 TO 15 
FT. WINDS ALONG THE BAJA COAST REMAIN LIGHT. SOME POSSIBLE 
INCREASE IN OFFSHORE WINDS PARTICULARLY THROUGH GAP AREAS DUE TO 
THE STRENGTHENING HIGH PRES OVER MEXICO AND WORKING IT'S WAY 
DOWN TO CENTRAL AMERICA. LITTLE CHANGE TO CROSS EQUATORIAL WINDS 
W OF 100W BUT E OF 100W GFS MODEL SHOWS SOME INCREASE TO 15 TO 
20 KT BUT GRADIENT WEAK SO NOT SURE WHY.

$$
RRG