000
AXPZ20 KNHC 060916
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC SUN MAR 06 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 WAS ANALYZED FROM 01N80W 
TO 03N89W TO 02N95W TO 04N123W TO 02N140W. SCATTERED MODERATE 
CONVECTION WAS WITHIN 120 NM N AND 60 NM S OF THE ITCZ AXIS 
BETWEEN 106W AND 128W.

...DISCUSSION...
A DEEP LAYERED LONGWAVE TROUGH IS MOVING EWD ACROSS THE 
MISSISSIPPI VALLEY WITH THE EQUATORWARD PORTION EXTENDING FROM 
THE NW GULF THROUGH NORTHERN MEXICO TO 22N106W THEN 
TRANSITIONING TO A TUTT-LIKE AXIS EXTENDING W-SW TO AN ILL 
DEFINED CYCLONIC VORTEX AT 17N133W. A BROAD AND FLAT DOWNSTREAM 
RIDGE TO THE SE OF THIS TROUGH SPANS FROM 105W ACROSS CENTRAL 
AMERICA WITH W-SW FLOW IN THE 30-50 KT RANGE FOUND ACROSS MUCH 
OF THIS AREA FROM 03N TO 18N. A REGION OF DIFFLUENT WINDS LIES 
TO THE W OF THIS RIDGING GENERALLY S OF 10N BETWEEN 115W AND 
125W AND COINCIDES WITH THE CONVECTION ALONG THE ITCZ DESCRIBED 
IN THE SECTION ABOVE. 

N OF THE AFOREMENTIONED DEEP LAYERED TROUGH LIES AN ANTICYCLONE 
CENTERED NEAR 23N127W AND ANOTHER DEEP LAYERED TROUGH LIES TO 
ITS W EXTENDING THROUGH THE HAWAIIAN ISLANDS. A SOUTHWESTERLY 
JET LIES BETWEEN THIS TROUGH AND ANTICYCLONE AND THE FLOW AROUND 
THE N SIDE OF THE ANTICYCLONE IS TRANSPORTING ABUNDANT MIDDLE TO 
UPPER MOISTURE INTO THE WRN U.S. THE TROUGH IS FORECAST TO SHIFT 
E AND TURN MORE POSITIVELY TILTED...FLATTENING THE BROAD UPPER 
RIDGE THROUGH SUN AND TRANSPORTING A COLD FRONT INTO NW PORTIONS 
OF THE AREA. A WEAKENING HIGH PRES CENTER CURRENTLY OVER NW 
WATERS AHEAD OF THE FRONT IS GRADUALLY SHIFTING SW...REDUCING 
THE PRES GRADIENT ALONG THE W COAST OF BAJA CALIFORNIA WHERE 
NWLY WINDS HAVE DROPPED BELOW ADVISORY CRITERIA OVERNIGHT. SW 
WINDS TO 20 KT WILL PREVAIL THIS MORNING ACROSS THE FAR NW 
CORNER OF THE AREA AHEAD OF THE FRONT...WITH THE FRONT MOVING 
SLOWLY INTO THE FORECAST AREA BY 1200 UTC. THE UPPER TROUGH IS 
EXPECTED TO ENTER THE W COAST OF THE U.S. BY MON MORNING AND 
FRACTURE FROM THE TRAILING PORTION TO THE SW. THIS WILL LEAVE 
THE COLD FRONT BEHIND AND FORCE IT TO WEAKEN AS IT BEGINS TO 
BECOME STRUNG OUT E TO W ALONG 27-28N MON. HIGH PRES WILL BUILD 
BEHIND THE FRONT MON INTO TUE IN CONTRAST TO THE LOW PRES INLAND 
ASSOCIATED WITH THE ADVANCING PORTION OF THE FRONT IN THE 
INTERIOR WESTERN U.S. THIS PRES GRADIENT WILL PRODUCE FRESH NWLY 
FLOW TO 25 KT OFF THE UPPER BAJA PENINSULA WATERS. 

GAP WINDS...
GULF OF CALIFORNIA...THE 0452Z ASCAT PASS CONTINUES TO SHOW 
FRESH NW WINDS IN THE CENTRAL GULF OF CALIFORNIA. THESE WINDS 
ARE FORECAST TO WEAKEN DUE TO THE WEAKENING PRES GRADIENT AND 
SHOULD DIMINISH TO A LIGHT BREEZE BY THIS AFTERNOON. 

GULF OF TEHUANTEPEC...A COLD FRONT ASSOCIATED WITH THE DEEP 
LAYERED TROUGH OVER MEXICO WILL INCREASE N WINDS IN THE GULF OF 
TEHUANTEPEC THIS MORNING THAT WILL REACH GALE FORCE LATE SUN 
THROUGH EARLY MON THEN QUICKLY DIMINISH.

GULF OF PAPAGAYO...GAP WINDS HAVE DIMINISHED ACROSS THE GULF OF 
PAPAGAYO IN ADVANCE OF THE COLD FRONT OVER MEXICO BUT ARE 
EXPECTED TO BEGIN TO PULSE AS FRESH E WINDS AGAIN EARLY MON AS 
HIGH PRES BUILDS OVER CENTRAL AMERICA BEHIND THE 
FRONT...INCREASING THE PRES GRADIENT OVER THE GULF OF PAPAGAYO.

.GULF OF PANAMA...FRESH N WINDS N OF 07N FROM 78W TO 81W WILL 
DIMINISH BELOW ADVISORY CRITERIA MON MORNING.

$$
SCHAUER/STRIPLING