000
AXPZ20 KNHC 062135
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC SUN MAR 06 2011

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W.

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2100 UTC.

...ITCZ...

THE INTERTROPICAL CONVERGENCE ZONE AXIS IS ANALYZED FROM 07N85W 
TO 05N100W TO 05N124W THEN CONTINUES FROM 05N128W TO 04N140W. 
SCATTERED MODERATE AND ISOLATED STRONG CONVECTION IS WITHIN 180 
NM N OF THE AXIS BETWEEN 111W AND 122W.

...DISCUSSION...

A DEEP LAYERED LONGWAVE TROUGH EXTENDS FROM THE EASTERN GULF OF 
MEXICO SW TO A COL NEAR 182118W. 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 09N117W TO S OF THE EQUATOR ALONG 117W...AND WEAK 
UPPER RIDGING ALONG 118W FROM 09N TO 17N.

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 32N127W 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 WITH 8 FT NW SWELL ALSO OUTRUNNING 
THE FRONT TO 20N. GALE CONDITIONS ARE EXPECTED AHEAD OF THE 
FRONT N OF 32N. THE FRONT WILL DISSIPATE DURING THE NEXT 24 
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.
 
A WEAK SURFACE TROUGH IS EMBEDDED IN THE ITCZ FROM 08N123W TO 
02N126W WITH A 1724Z ASCAT PASS INDICATING 20 KT WINDS WITHIN 
120 NM OF THE TROUGH AXIS N OF 05N. SCATTERED MODERATE 
CONVECTION IS WITHIN 120 NM OF THE TROUGH. THE TROUGH WILL 
SLOWLY WEAKEN AS IT MOVES W AROUND 15 KT DISSIPATING BY 48 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 NE 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 
COMMENCED AT 18Z. WINDS WILL DIMINISH BELOW GALE FORCE BY MON 
MORNING THEN WILL QUICKLY DIMINISH TO LESS THAN 20 KT BY MON 
EVENING.

GULF OF PAPAGAYO...WINDS ARE EXPECTED TO PULSE TO 20 KT LATE 
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 THIS EVENING DIMINISHING BELOW ADVISORY CRITERIA MON 
MORNING.

$$
LEWITSKY