000
AXPZ20 KNHC 050321
TWDEP 

TROPICAL WEATHER DISCUSSION    
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC FRI FEB 05 2010

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 
0100 UTC.

...ITCZ...

INTERTROPICAL CONVERGENCE ZONE AXIS ANALYZED ALONG 04N77W TO  
04N90W TO 08N105W TO 07N125W TO 03N140W. SCATTERED MODERATE 
CONVECTION CAN BE FOUND WITHIN 60 NM N OF THE ITCZ AXIS BETWEEN 
90W AND 92W.

...DISCUSSION...

THE DEEP LAYER TROUGH PASSING THROUGH MEXICO DOMINATES THE 
WEATHER PATTERN OVER MUCH OF THE REGION W OF 110W. ALOFT...A 
POWERFUL ZONAL JET ALONG 30N LIES OVER N WATERS W OF 130W. WINDS 
TURN NORTHWESTERLY AS IT APPROACHES THE TROUGH AXIS AND WEAKEN 
TO 80-100 KT AS THEY ROUND THE BASE OF THE TROUGH AND TURNS INTO 
A 120-140 KT SOUTHERLY JET INTO THE U.S. SOUTHERN PLAINS. UPPER 
LEVEL DIFFLUENCE BETWEEN THIS TROUGH AND AN UPPER RIDGE AXIS 
OVER FLORIDA IS SUPPORTING WIDESPREAD CLOUDINESS AND 
PRECIPITATION PRIMARILY E OF THE TROUGH AXIS OVER NE MEXICO AND 
THE REMAINDER OF MEXICO S OF 20N. A BROAD SURFACE TROUGH 
REFLECTION OF THE TROUGHING ALOFT LIES OVER THE TROPICAL PACIFIC 
WATERS. TWO TROUGHS ARE DEPICTED ON THE SURFACE MAP HERE.  THE 
EASTERN TROUGH FROM 16N98W TO 11N100W IS MORE CONVECTIVELY 
ACTIVE...WITH ISOLATED MODERATE CONVECTION NOTED WITHIN 90 NM E 
OF THE TROUGH FROM 14N99W TO 11N100W. THE SECOND TROUGH HAS SEEN 
STRONGER WINDS ASSOCIATED WITH IT AS THE PRES GRADIENT IS 
STRONGER HERE ON THE EASTERN EDGE OF THE SUBTROPICAL RIDGE. 
THESE TROUGHS ARE EXPECTED TO SHIFT EASTWARD AND DISSIPATE FRI 
AS THE SUPPORTING TROUGHING ALOFT MOVES EASTWARD. LOW LEVEL 
MOISTURE IS CONVERGED BETWEEN THESE TROUGHS WITH PRECIPITABLE 
WATER VALUES AROUND 2.0 INCHES...BUT THE DEEP CONVECTION 
PREVIOUSLY FOUND IN THIS AREA HAS DIMINISHED AS THE REAR RIGHT 
QUADRANT OF THE SOUTHERLY UPPER JET PULLS EASTWARD AWAY FROM THE 
LOW LEVEL MOISTURE POOL. HOWEVER...40-60 KT MID-LEVEL SW WINDS 
CONTINUE TO PUMP MOSITURE NORTHEASTWARD INTO MEXICO...WITH A 
BAND OF MID TO HIGH CLOUDS FOUND WITHIN 210 NM EITHER SIDE OF A 
LINE FROM THE ITCZ NEAR 110W TO 18N97W. MODERATE TO STRONG 
SUBSIDENCE DOMINATES THE REGION JUST EAST OF HERE AND INTO 
CENTRAL AMERICA FROM HONDURAS SOUTHWARD.

1016 MB HIGH PRES NEAR 25N120W HAS BEEN SQUEEZED EASTWARD BY A 
COLD FRONT MOVING THROUGH OVER NW WATERS. TRADE WINDS HAVE 
DECREASED BELOW 20 KT AS A RESULT OF THE WEAK HIGH PRES 
DISPLACED WELL AWAY FROM THE ITCZ. THE AFOREMENTIONED COLD FRONT 
WILL CONTINUE TO PASS EASTWARD INTO SOUTHERN CALIFORNIA BY FRI 
EVENING...DISSIPATING OVER NE WATERS SAT EVENING. THE GALE 
WARNING PREVIOUSLY IN EFFECT FOR THE SOUTHERLY FLOW IN ADVANCE 
OF THIS FRONT WAS BROUGHT DOWN AT 1800 UTC. THE 1834 UTC ASCAT 
PASS SUGGESTED THAT WINDS WERE RAPIDLY DECREASING BELOW 30 KT AS 
THE CORE OF THE SYSTEM LIFTS NORTHEASTWARD. WINDS ARE CURRENTLY 
BELIEVED TO BE IN THE 20 TO 25 KT RANGE IN THIS SOUTHERLY FLOW. 
SEAS 12 FT AND HIGHER ALONG 30N APPEAR TO BE MOVING E MORE 
SLOWLY THAN THE WAVEWATCH MODEL IS PREDICTING. THIS CONCLUSION 
WAS BASED ON THE JASON1 PASS AROUND 2100 UTC AND 10 FT SHIP 
OBSERVATIONS AT 0000 UTC FROM BOTH WDD6042 NEAR 34N123W AND WRFJ 
NEAR 35N126W. ANOTHER COLD FRONTAL SYSTEM CURRENTLY NORTH OF 
HAWAII WILL APPROACH THIS WEAKENING SYSTEM TOMORROW...SUSTAINING 
THE 20 KT WINDS OVER NW WATERS BEFORE THEY DIMINISH SAT. THIS 
NEW SYSTEM WILL BRING ANOTHER SURGE OF NW SWELL INTO THE 
REGION...WITH SEAS EXPECTED TO REACH 22 FT IN FAR NW WATERS BY 
FRI AFTERNOON WHICH WILL SUBSIDE TO 16 FT BY SAT EVENING AS THE 
SWELL PROGRESSES EASTWARD. HIGH PRES BEHIND THE COLD FRONT WILL 
SHIFT THE RIDGE FARTHER W...ALLOWING 20 KT NE TRADE WINDS TO 
RETURN TO W WATERS BY FRI EVENING.

GAP WINDS...
ASCAT DATA FROM 1516 UTC SHOWS 20 TO 25 KT WINDS THROUGH THE 
GULF OF PAPAGAYO. THESE GAP WINDS ARE EXPECTED TO DIMINISH BELOW 
20 KT BY TOMORROW AFTERNOON. SIMILARLY...THE 20 TO 25 KT WINDS 
SEEN IN THAT ASCAT PASS IN THE GULF OF PANAMA ARE EXPECTED TO 
DIMINISH SAT MORNING WHEN THE PRES GRADIENT BETWEEN LOW PRES IN 
COLOMBIA AND HIGH PRES TO THE NORTH WEAKENS AS A COLD FRONT 
ENTERS THE FAR NW CARIBBEAN. THE NEXT TEHUANTEPEC EVENT WILL 
BEGIN EARLY SAT BEHIND THIS FRONT...BUT IT DOES NOT APPEAR THAT 
IT WILL BECOME STRONG ENOUGH TO REQUIRE A WARNING.

ELSEWHERE...FORECAST WATERS ARE DOMINATED BY NW SWELL AND 
GENERALLY LIGHT WINDS. 

FOR ADDITIONAL INFORMATION PLEASE VISIT 
HTTP://WWW.HURRICANES.GOV/MARINE

$$
SCHAUER