000
AXPZ20 KNHC 060346
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC SUN MAR 06 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 
0200 UTC.

...ITCZ...
AXIS ANALYZED FROM 03N77W TO 03N83W TO 07N99W TO 03N110W TO 
04N130W TO 06N134W TO 05N140W. SCATTERED MODERATE CONVECTION WAS 
NOTED WITHIN 90 NM N OF AXIS W OF 110W.

...DISCUSSION...
DEEP LAYERED LONGWAVE TROUGH MOVING EWD ACROSS CENTRAL U.S. THIS 
EVENING WITH EQUATORWARD PORTION EXTENDING FROM MIDDLE TO UPPER 
CYCLONE ALONG TEXAS-LOUISIANA BORDER SW THROUGH NORTHERN MEXICO 
TO 19N112W THEN TRANSITIONING TO A TUTT LIKE AXIS EXTENDING W-SW 
TO ILL DEFINED CYCLONIC VORTEX AT 16N136W.  BROAD FLAT 
DOWNSTREAM RIDGE TO THE SE SPANS FROM 105W ACROSS CENTRAL 
AMERICA. NW OF THE UPPER TROUGH A BROAD AND LARGE UPPER RIDGE 
WAS CENTERED ALONG 128W AND EXTENDED N-NE BEYOND 40W...AND WAS 
TRANSPORTING ABUNDANT MIDDLE TO UPPER MOISTURE OVER THE RIDGE 
AND INTO THE WRN U.S. S OF ALL OF THESE FEATURES ZONAL FLOW 
ALOFT GENERALLY PREVAILS...EXCEPT WHERE PERSISTENT DEEP 
CONVECTION ALONG THE ITCZ BETWEEN 120W AND 150W WAS INDUCING 
DIFFLUENT FLOW ALOFT. 

SHARP LARGE AMPLITUDE TROUGH WELL W OF THE AREA IS HELPING TO 
PULL MIDDLE TO UPPER MOISTURE OUT OF THE TROPICS AND OVER THE 
BROAD RIDGE. THIS TROUGH IS FORECAST TO SHIFT E...AMPLIFY 
FURTHER AND FLATTEN THE BROAD UPPER RIDGE THROUGH SUN...AND 
TRANSPORT A COLD FRONT INTO NW PORTIONS OF THE AREA. S TO SWLY 
WINDS OF 20 TO 25 KT WILL PREVAIL TONIGHT ACROSS THE NW CORNER 
OF THE AREA AHEAD OF THE FRONT...WITH THE FRONT MOVING SLOWLY 
INTO THE NW CORNER BY 1200 UTC SUN. UPPER TROUGH IS FORECAST TO 
ENTER W COAST OF U.S. BY 1200 UTC MON AND BREAK OR FRACTURE FROM 
TRAILING PORTION TO THE SW. THIS WILL LEAVE COLD FRONT BEHIND 
AND FORCE IT TO WEAKEN AS IT BEGINS TO BECOME STRUNG OUT E TO W 
ALONG 26-27N MON...WITH HIGH PRES BUILDING BEHIND AND PRODUCING 
FRESH NWLY FLOW TO 25 KT OFF THE UPPER BAJA PENINSULA WATERS. 

AT THE SURFACE...
WEAKENING HIGH PRES CENTER 1024 MB AT 30N127W IS GRADUALLY 
SHIFTING SW...ANS REDUCING THE PRES GRADIENT ALONG THE W COAST 
OF BAJA CALIFORNIA...WHERE NWLY WINDS OF 20 KT ARE SHRINKING IN 
AREAL COVERAGE TO N OF 25N THIS EVENING. THIS AREA OF 20 KT NW 
WINDS WILL SHRINK FURTHER OVERNIGHT AS THE RIDGE DROPS FURTHER 
SW AND WEAKENS.

GULF OF CALIFORNIA...FRESH NW WINDS WILL CONTINUE TO GRADUALLY  
WEAKEN OVERNIGHT DUE TO WEAKENING PRES GRADIENT...AND SHOULD 
DIMINISH TO A LIGHT BREEZE BY SUN NIGHT. 

GULF OF TEHUANTEPEC...N WINDS WILL INCREASE EARLY SAT IN 
RESPONSE TO GULF OF MEXICO COLD FRONT AND REACH GALE FORCE LATE 
SUN THROUGH EARLY MON...THEN QUICKLY DIMINISH.

GULF OF PAPAGAYO...GAP WINDS HAVE DIMINISHED ACROSS THE GULF 
THIS EVENING BUT ARE EXPECTED TO BEGIN TO PULSE MODERATE TO 
FRESH E WINDS AGAIN EARLY MON.

.GULF OF PANAMA...MODERATE BREEZE N OF 07N FROM 78W TO 81W WILL 
DIMINISH TO LIGHT BREEZE SUN AFTERNOON.

$$
STRIPLING