000
AXPZ20 KNHC 080919
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC TUE MAR 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 
0730 UTC.

...ITCZ...

THE INTERTROPICAL CONVERGENCE ZONE AXIS IS ANALYZED FROM AXIS 
FROM 01N79W TO 03N90W TO 02N98W TO 05N108W TO 04N140W. SCATTERED 
MODERATE CONVECTION CAN BE FOUND WITHIN 150 NM N AND 60 NM S OF 
THE ITCZ AXIS BETWEEN 93W AND 114W.

...DISCUSSION...

A LARGE FLATTENED UPPER LEVEL RIDGE COVERS THE MAJORITY OF THE 
AREA FROM THE EQUATOR TO 22N E OF 120W. W FLOW ALOFT AT 40-60 KT 
AND MAINLY DRY AND STABLE AIR IS IN PLACE N OF 10N E OF 120W 
UNDER THE RIDGE. ELSEWHERE...CONVECTION IS BEING ENHANCED ALONG 
THE ITCZ BETWEEN 93W AND 114W AS DESCRIBED IN THE ITCZ SECTION 
UNDER A REGION OF UPPER LEVEL DIFFLUENCE ALONG THE UPPER LEVEL 
RIDGE AXIS.

THE POSITIVELY TILTED UPPER TROUGH THAT EXTENDED ACROSS N WATERS 
MON HAS BROKEN IN TWO. THE EASTERN PORTION OF THE TROUGH LIES 
FROM NEAR EL PASO TEXAS THROUGH NW MEXICO TO 26N118W WHILE THE 
WESTERN PORTION LIES FROM 30N130W THROUGH 24N140W AND EXTENDS 
JUST SE OF HAWAII. A 30-50 KT SOUTHWESTERLY JET AXIS LIES AHEAD 
OF THE TROUGH OVER NW WATERS AND IS ADVECTING MOISTURE FROM THE 
DEEP TROPICS S OF HAWAII NORTHEASTWARD INTO THE FORECAST AREA. 
THIS MOISTURE HAS MANIFESTED ITSELF AS CIRRUS PRIMARILY OVER THE 
FORECAST AREA FROM 16N TO 28N W OF 126W. RIDGING ALOFT CAN BE 
FOUND BETWEEN THIS TROUGH AND ANOTHER TROUGH THAT LIES ALONG 
126W S OF 23N TO A WEAK UPPER LOW NEAR 00N126W.

AT THE SURFACE...1028 MB HIGH PRES JUST N OF THE FORECAST AREA 
NEAR 33N132W EXTENDS A RIDGE INTO THE AREA TO 22N112W. LOWER 
PRES LIES OVER MAINLAND MEXICO IS REFLECTING THE EASTERN PORTION 
OF THE AFOREMENTIONED UPPER TROUGH. THE TIGHT PRES GRADIENT OFF 
THE W COAST OF BAJA CALIFORNIA BETWEEN THESE FEATURES IS 
GENERATING NW-N 20-25 KT WINDS AND SEAS TO 10 FT IN NW SWELL. 
WINDS WILL DIMINISH TO 20 KT THIS EVENING AND THEN TO LESS THAN 
20 KT WED AS THE PRES GRADIENT RELAXES WITH SEAS ALSO SUBSIDING 
TO LESS THAN 8 FT WED EVENING.

THE 0550Z ASCAT PASS SHOWS A NARROW AREA OF FRESH NE TRADE WINDS 
OVER W WATERS FROM 17N TO 22N W OF 120W WHILE SHIP V7FF2 
REPORTED FRESH TRADES AND 9 FT SEAS NEAR 21N124W AT 00Z. THIS 
AREA OF TRADES IS FORECAST TO SHIFT SOUTHWESTWARD OVER THE NEXT 
FEW DAYS IN RESPONSE TO THE HIGH PRES CENTER MOVING 
SOUTHWESTWARD AHEAD OF THE NEXT COLD FRONT EXPECTED TO ENTER NW 
WATERS OVERNIGHT WED NIGHT. NW SWELL WILL DAMPEN OUT IN THE AREA 
OF TRADE WINDS TO LESS THAN 8 FT BY WED WHILE THE FRONT WILL 
ENTER THE AREA WITH LITTLE FANFARE OTHER THAN AN INCREASE IN NW 
SWELL TO ABOVE ADVISORY CRITERIA BY THU MORNING.

GAP WINDS...
GULF OF CALIFORNIA...NORTHERLY WINDS ARE EXPECTED TO INCREASE TO 
20 KT THIS MORNING AND CONTINUE THROUGH 48 HOURS AS THE TIGHT 
PRES GRADIENT BETWEEN TROUGHING OVER THE CENTRAL CONUS AND 
MEXICO AND RIDGING OVER THE EASTERN NORTH PACIFIC SHIFTS 
EASTWARD OVER THE GULF OF CALIFORNIA.

GULF OF TEHUANTEPEC...WINDS WILL REMAIN BELOW 20 KT THROUGH LATE 
THU WHEN ANOTHER GALE FORCE WIND EVENT IS EXPECTED.

GULF OF PAPAGAYO...WINDS ARE EXPECTED TO PULSE TO 20 KT THIS 
MORNING AND THEN WILL REMAIN LESS THAN 20 KT THROUGH 48 HOURS.

$$
SCHAUER/LEWITSKY