000
AXPZ20 KNHC 080922
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC TUE FEB 08 2011

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 
0715 UTC.

...ITCZ...
THE INTERTROPICAL CONVERGENCE ZONE IS ANALYZED ALONG AN AXIS 
FROM 05N77W TO 04N97W TO 08N115W TO 04N133W TO 03N140W. 
SCATTERED MODERATE CONVECTION IS WITHIN 60 NM S OF THE ITCZ AXIS 
BETWEEN 86W AND 88W AS WELL AS WITHIN 150 NM N OF THE ITCZ AXIS 
BETWEEN 113W AND 124W.

...DISCUSSION...
A REX BLOCK PATTERN REMAINS IN PLACE ACROSS THE UPPER LEVELS 
WITH AN UPPER RIDGE ANCHORED N OF THE AREA NEAR 41N134W AND TO 
THE N OF AN UPPER LOW COMPLEX GENERALLY CENTERED NEAR 25N135W. 
THIS PATTERN IS EXPECTED TO GRADUALLY BREAK DOWN OVER THE NEXT 
FEW DAYS LEAVING A SHARP UPPER TROUGH OVER THE NW CORNER OF THE 
FORECAST AREA BY EARLY THU MORNING. AT THE SURFACE...A 1040 MB 
HIGH PRES CENTER NOW LIES NEAR 47N135W. THIS HIGH WILL WEAKEN AS 
IT SLOWLY MIGRATES EASTWARD. THE AREA OF FRESH TRADE WIND FLOW 
HAS SHRUNK CONSIDERABLY OVER THE PAST 24 HOURS AND IS EXPECTED 
TO REMAIN A SMALL AREA OVER W CENTRAL WATERS FOR THE NEXT FEW 
DAYS. STRONG NE WINDS BETWEEN THE HIGH PRES TO THE NORTH AND 
TROUGHING ALONG THE CALIFORNIA COAST ARE REACHING INTO THE AREA 
N OF 27N W OF 128W ACCORDING TO THE 0534Z ASCAT PASS. A DEEP 
LAYER TROUGH OVER THE WESTERN CONUS WILL SHED SOME SHORTWAVE 
ENERGY SOUTHWESTWARD TOWARD THE AFOREMENTIONED UPPER LOW COMPLEX 
WED INTO THU. THIS WILL EXPAND THE SURFACE TROUGHING OFF THE 
CALIFORNIA COAST SOUTHWESTWARD AND EVENTUALLY BREAK OFF A 
PORTION OF THE TROUGH INTO THE FORECAST AREA. WINDS WILL SHIFT 
MORE NORTHERLY OVER N CENTRAL WATERS BY WED AS A RESULT. SWELL 
GENERATED BY THESE WINDS WILL PROPAGATE SOUTHWARD...MIXING WITH 
LONG PERIOD NW SWELL OVER NW WATERS TODAY INTO THU. 

GAP WINDS...
GULF OF TEHUANTEPEC...THE MAIN FORECAST ISSUE OF THE PERIOD IS 
THE STORM FORCE WIND EVENT IN THE GULF OF TEHUANTEPEC GENERATED 
AS DENSER COLD AND DRY AIR PUSHED S OVER THE WESTERN GULF OF 
MEXICO AND INTO THE CHIVELA PASS. SHIP PDGS REPORTED 25 KT WINDS 
NEAR 14.5N93.7W AT 0300Z...WELL SE OF THE CLIMATOLOGICAL REGION 
OF STRONGEST WINDS DURING SUCH EVENTS. WHILE THE ASCAT PASS FROM 
0346Z MISSED THIS REGION...LAND BASED STATIONS AT COATZACOALCOS 
AND SALINA CRUZ MEXICO REPORTED SEVERAL HOURS OF SUSTAINED 30 KT 
WINDS AND THE LAST REPORT FROM IXTEPEC MEXICO AT 0400Z WAS 30 KT 
WITH GUSTS TO 40 KT. WINDS ARE KNOWN TO BE SIGNIFICANTLY HIGHER 
OVER THE OPEN WATERS OF THE GULF OF TEHUANTEPEC THAN THESE LAND 
BASED STATIONS DURING SUCH EVENTS. WHILE WE LIKELY HAVE GALE 
FORCE WINDS IN THE GULF OF TEHAUNTEPEC...THE NUMERICAL MODELS DO 
NOT SUGGEST THAT THERE IS A STORM FORCE WIND EVENT THERE AT THIS 
TIME. HOWEVER...WITH A LACK OF INFORMATION AVAILABLE TO CONFIRM 
THAT THERE IS NO STORM EVENT...THE FORECAST PRODUCTS WILL 
CONTINUE TO REFLECT STORM CONDITIONS NOW THAT WILL QUICKLY DROP 
BELOW GALE FORCE TUE AFTERNOON AS THE PROGRESSIVE FRONT QUICKLY 
MOVES E OF THE AREA. 

GULF OF PAPAGAYO...WINDS JUST DOWNSTREAM OF THE GULF OF PAPAGAYO 
HAVE BEEN PULSING TO 20 KT MAINLY DURING THE OVERNIGHT AND EARLY 
MORNING HOURS AT THE TIME OF PEAK DRAINAGE FLOW OVER THE PAST 
FEW DAYS. AS THE COLD FRONT WHICH PUSHED THROUGH THE GULF OF 
TEHUANTEPEC MON MAKES ITS WAY FURTHER S...LOOK FOR WINDS IN 
PAPAGAYO TO INCREASE TO 20 TO 25 KT EARLY TUE MORNING. WINDS 
WILL QUICKLY DIMINISH BACK TO 20 KT IN THE OVERNIGHT AND EARLY 
MOVING HOURS BY WED EVENING BEHIND THE FAST MOVING FRONT.

GULF OF CALIFORNIA...A SECOND COLD FRONT WILL APPROACH THE 
NORTHERN GULF OF CALIFORNIA LATE TUE NIGHT AND INCREASE WINDS TO 
20 TO 25 KT IN THE NORTHERN GULF WED MORNING BEFORE DIMINISHING 
TO 20 KT OVER THE NORTHERN AND CENTRAL GULF OF CALIFORNIA EARLY 
THU MORNING.

$$
SCHAUER