000
AXPZ20 KNHC 070333
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC MON MAR 07 2011

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 
0300 UTC.

...ITCZ...

THE INTERTROPICAL CONVERGENCE ZONE AXIS IS ANALYZED FROM 04N90W 
TO 01N96W THEN CONTINUES FROM 05N105W TO 04N116W THEN CONTINUES 
FROM 03N130W TO 02N140W. SCATTERED MODERATE CONVECTION IS WITHIN 
60 NM S OF THE AXIS BETWEEN 92W AND 94W AND ALSO WITHIN 180 NM N 
OF THE AXIS BETWEEN 111W AND 116W.

...DISCUSSION...

A DEEP LAYERED LONGWAVE TROUGH EXTENDS FROM THE EASTERN GULF OF 
MEXICO SW TO A COL NEAR 18N119W. W-SW FLOW ALOFT AT 30-50 KT IS 
PREVALENT ACROSS THE MAJORITY OF THE AREA S OF THE UPPER TROUGH 
AXIS WITH MAINLY DRY AND STABLE AIR IN PLACE BETWEEN THE ITCZ 
AND THE TROUGH AXIS. CONVECTION IS BEING ENHANCED ALONG THE ITCZ 
AS DESCRIBED ABOVE BETWEEN ANOTHER UPPER TROUGH THAT REACHES 
FROM NEAR 07N110W TO SW OF THE EQUATOR...AND WEAK UPPER RIDGING 
ALONG 119W FROM 08N TO 16N.

ANOTHER UPPER TROUGH IS APPROACHING THE NW CORNER OF THE AREA 
FROM THE W WITH A 90-120 KT JET AXIS AHEAD OF THE TROUGH 
ADVECTING PLENTIFUL MOISTURE FROM THE DEEP TROPICS ACROSS THE 
NORTHERN WATERS AROUND ANOTHER UPPER RIDGE ORIENTED ALONG 121W 
WHICH EXTENDS FROM AN ANTICYCLONE LOCATED NEAR 22N121W. 
ELSEWHERE ALOFT A CUTOFF UPPER CYCLONIC VORTEX IS POSITIONED 
NEAR 17N134W WHERE IT IS EXPECTED TO REMAIN NEARLY STATIONARY 
DURING THE NEXT FEW DAYS.

AT THE SURFACE...A WEAK COLD FRONT EXISTS FROM 32N125W TO 
28N140W AND IS SUPPORTED BY THE ABOVE MENTIONED APPROACHING 
UPPER TROUGH. N TO NE WINDS TO 20 KT WITH SEAS TO 9 FT IN NW 
SWELL ARE BEHIND THE FRONT. GALE CONDITIONS ARE EXPECTED AHEAD 
OF THE FRONT N OF 32N. THE FRONT WILL DISSIPATE DURING THE NEXT 
24 TO 36 HOURS. A TIGHT PRES GRADIENT WILL SET UP JUST W OF THE 
BAJA CALIFORNIA PENINSULA FROM 24 THROUGH 48 HOURS WITH 
NORTHERLY 20 KT WINDS USHERING IN NW SWELL UP TO 11 FT W OF THE 
PENINSULA BY 48 HOURS.

1010 MB LOW PRES IS POSITIONED NEAR 04N117W. SCATTERED MODERATE 
AND ISOLATED STRONG CONVECTION IS WITHIN 90 NM IN THE E AND 
WITHIN 240 NM IN THE W AND NW QUADRANTS. NO SIGNIFICANT 
DEVELOPMENT OF THIS LOW IS ANTICIPATED. A WEAK SURFACE TROUGH IS 
EMBEDDED IN THE ITCZ FROM 09N121W TO 03N129W AND AN EARLIER 
ASCAT PASS INDICATED 20 KT WINDS WITHIN 240 NM W OF THE TROUGH 
AXIS N OF 05N. EARLIER CONVECTION HAS WEAKENED. THE TROUGH WILL 
CONTINUE TO WEAKEN AS IT MOVES W AROUND 15 KT DISSIPATING BY 24 
HOURS.

GAP WINDS...
GULF OF CALIFORNIA...A COLD FRONT WILL MOVE THROUGH THE NORTHERN 
GULF MON NIGHT AND NORTHERLY WINDS ARE EXPECTED TO INCREASE TO 
20 KT BEHIND THE FRONT TUE MORNING. A BRIEF EPISODE OF 20 KT SW 
WINDS ARE ALSO POSSIBLE AHEAD OF THE FRONT IN THE NORTHERN GULF 
ALTHOUGH WILL REFRAIN FROM MENTIONING IN THE FORECAST FOR NOW 
UNTIL MODEL DATA BETTER SUPPORTS THAT SCENARIO.

GULF OF TEHUANTEPEC...A COLD FRONT E OF THE ISTHMUS OF 
TEHUANTEPEC IN THE GULF OF MEXICO IS USHERING IN STRONG 
NORTHERLY WINDS IN THE GULF OF TEHUANTEPEC AND THE GALE WARNING 
CONTINUES THROUGH 12Z MON. AN OBSERVATION AT LAND-BASED STATION 
IXTEPEC MEXICO RECENTLY REPORTED GUSTS TO 35 KT. WINDS WILL 
QUICKLY DIMINISH TO LESS THAN 20 KT BY MON EVENING.

GULF OF PAPAGAYO...WINDS ARE EXPECTED TO PULSE TO 20 KT LATER 
TONIGHT AS THE PRES GRADIENT INCREASES BEHIND A COLD FRONT  
WHICH WILL MOVE INTO THE NW CARIBBEAN THIS EVENING. WINDS WILL 
THEN CONTINUE TO PULSE TO 20 KT MAINLY DURING THE LATE NIGHT AND 
EARLY MORNING HOURS THROUGH TUE MORNING.

GULF OF PANAMA...FRESH N WINDS N OF 07N BETWEEN 78W AND 80W WILL 
OCCUR LATER TONIGHT EVENING DIMINISHING BELOW ADVISORY CRITERIA 
MON MORNING.

$$
LEWITSKY