000
AXPZ20 KNHC 151015
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC SAT DEC 15 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 
1000 UTC.
 
...ITCZ...

INTERTROPICAL CONVERGENCE ZONE AXIS IS CENTERED ALONG 7N78W 6N90W
6N100W 7N110W 10N118W 10N130W 9N140W. SCATTERED MODERATE/ISOLATED
STRONG CONVECTION IS WITHIN 120 NM N OF THE AXIS BETWEEN 
121W-125W...AND WITHIN 60 NM S OF THE AXIS E OF 81W TO THE COAST 
OF COLOMBIA. SCATTERED MODERATE CONVECTION IS WITHIN 30 NM EITHER
SIDE OF THE AXIS BETWEEN 125W-130W.

...DISCUSSION...

MID/UPPER LEVEL TROUGH/SHEAR AXIS EXTENDS FROM A FAIRLY LARGE 
CYCLONIC CIRCULATION OVER NE NEW MEXICO SWWD THROUGH 30N108W
...TO OVER SOUTHERN BAJA CALIFORNIA...AND CONTINUES TO 26N120W 
27N130W AND TO ANOTHER MID TO UPPER LEVEL CYCLONIC CIRCULATION 
NEAR 25N138W. ANTICYCLONIC UPPER LEVEL FLOW WAS MOVING SWD INTO 
THE AREA N OF THE TROUGH AXIS WITH AN ASSOCIATED SHORTWAVE RIDGE 
N OF THE AREA ALONG 120W. SATELLITE DERIVED WINDS FROM GOES-11 
INDICATED A 90-110 KT SUBTROPICAL JTST S OF THE TROUGH AXIS 
EXTENDING FROM ABOUT 21N131W ENE THROUGH 22N125W 24N120W TO 
ACROSS THE SOUTHERN TIP OF BAJA CALIFORNIA AND NEWD INTO NW 
MEXICO AND THE SRN GREAT PLAINS OF THE U.S. THE SUBTROPICAL JET 
CONTINUES TO ADVECT ABUNDANT TROPICAL MOISTURE ACROSS NORTHERN 
MEXICO INTO THE SRN PLAINS...FUELING YET ANOTHER MAJOR WINTER 
STORM OVER THE SRN PLAINS AND THE MISSISSIPPI RIVER VALLEY. 

THE FLOW AT THE UPPER LEVELS WAS MAINLY ANTICYCLONIC OVER THE 
DEEP TROPICS S OF THE JTST W OF 110W...AND E OF 105W WITH A 
NARROW SHEAR AXIS ALONG 109W SEPARATING THE REGIONS OF 
ANTICYCLONIC FLOW. CONVECTION REMAINS RATHER LIMITED OVER
THE E PORTION OF THE AREA UNDER MODERATE SUBSIDENCE.

AT THE SURFACE...A NEARLY STATIONARY 1030 MB HIGH CENTER IS NEAR 
32N131W WITH A RIDGE SE THROUGH 26N123W TO 18N109W. HIGH PRES 
COVERS THE REGION N OF 12N W OF 109W. RESULTANT NE-E TRADES ARE 
IN THE RANGE OF 20-25 KT. BROKEN TO OVERCAST STRATOCUMULUS 
CLOUDS MOVING WSW WITH POSSIBLE ISOLATED SHOWERS COVER ARE 
PRESENT N OF 10N W OF 120W.

GAP WINDS...
PRESENTLY...WIND AND SEAS CONDITIONS ARE QUIET IN THE GAP WIND 
AREAS WITH THE EXCEPTION OF 20 KT WINDS IN THE GULF OF 
CALIFORNIA. AS STRONG HIGH PRESSURE BUILDS SWD IN THE GREAT 
BASIN AND E OF THE SIERRA MADRE IN MEXICO N-NE WINDS ARE FORECAST
TO INCREASE TO 20 TO 25 KT IN THE GULF OF CALIFORNIA WITHIN 24 
HOURS. THIS SAME SYNOPTIC SETUP WILL BRING GALE FORCE WINDS OF
30-40 KT IN THE GULF OF TEHUANTEPEC WITHIN THE NEXT 36 TO 48 
HOURS. THESE WINDS MAY POSSIBLY GUSTS UP TO HIGHER SPEEDS PER 
GFS AND NAM MODEL WIND GUIDANCE. SEAS THERE WILL ALSO BUILD TO
LARGE RANGES.

$$
COBB