000 AXPZ20 KNHC 171611 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1605 UTC THU MAR 17 2011 TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM THE EQUATOR TO 32N...EAST OF 140W. BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1545 UTC. ...ITCZ... THE INTERTROPICAL CONVERGENCE AXIS IS CENTERED ALONG 5N78W 2N93W TO 5N105W 7N115W 3N131W 6N140W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 60 NM OF AXIS BETWEEN 128W-131W AND 60 NM S OF THE AXIS E OF 79W. SCATTERED MODERATE WITHIN 180 NM N OF THE AXIS BETWEEN 111W-118W...AND WITHIN 60 NM N OF THE AXIS BETWEEN 121W-127W. ...DISCUSSION... A RATHER BROAD UPPER LEVEL TROUGH EXTENDS FROM NEAR 32N133W TO NEAR 19N140W. A JET STREAM BRANCH DIVES SOUTHEASTWARD INTO THE REGION THROUGH 27N140W AND ROUNDS THE BASE OF THE TROUGH TO 24N130W AND NE TO ACROSS NORTHERN BAJA CALIFORNIA. MAXIMUM JET STREAM WINDS ARE IN THE RIGHT FRONT QUADRANT WHERE SPEEDS RANGE FROM 60-85 KT. UPPER LEVEL MOISTURE IN THE FORM OF BROKEN TO SCATTERED HIGH CIRRUS CLOUDS ARE WITHIN 300 NM SE OF THE JET STREAM. THESE CLOUDS ARE BEING CHANNELED NORTHEASTWARD BY THE JET STREAM WINDS TO WELL INLAND THE INTERMOUNTAIN REGION OF THE U.S. TO THE S OF THE UPPER LEVEL TROUGH...MODERATE TO STRONG SUBSIDENCE COVERS THE AREA FROM 13N TO 23N W OF 129W...AND WITHIN 300 NM EITHER SIDE OF LINE FROM 16N113W TO 19N123W. THIS IS MAINTAINING RATHER DRY AND STABLE CONDITIONS AT THE SURFACE WHERE BROKEN TO SCATTERED STRATOCUMULUS CLOUDS MOVING SW TO W ARE NOTED. RATHER ACTIVE ITCZ CONVECTION CONTINUES UNDER PRONOUNCED MID/UPPER LEVEL RIDGING W OF ABOUT 108W...WITH FLOW ALOFT THAN BECOMING DIFFLUENT TO THE E OF 108W. AS THE ITCZ CONVECTION CONTINUES TO PERCOLATE...THE ASSOCIATED UPPER LEVEL DEBRIS MOISTURE IS BEING ADVECTED E AND NE UNDER THE STEERING OF THE UPPER LEVEL SW WINDS TO THE S OF THE UPPER TROUGH AS DESCRIBED ABOVE. THIS MOISTURE IS IN THE FORM OF SCATTERED TO BROKEN CIRRUS CLOUDS WHICH ARE CROSSING OVER THE CENTRAL PORTION OF MEXICO AND REACHING TO THE FAR WESTERN GULF OF MEXICO. THE FAR EASTERN SECTION OF THE DISCUSSION AREA S OF 20N AND E OF 108W IS PRETTY MUCH VOID OF MOISTURE AND DEEP CONVECTION AS SUBSIDENCE THROUGHOUT AS INDUCED BY CONFLUENT FLOW KEEP ATMOSPHERIC CONDITIONS THERE RATHER STABLE...WITH ONLY A FEW LOW CLOUD STREAMERS WITH ISOLATED SHOWERS AND WEAK CONVECTION SEEN TO THE SW OF CENTRAL AMERICA FROM 11N-13N E OF 100W...AND FROM 8N-13N BETWEEN 100W-108W. SCATTERED TO BROKEN LOW MOVING W WITH ISOLATED SHOWERS ARE CONFINED FROM 2N-6N BETWEEN 87W-102W. THE SOUTHERN PORTION OF A WEAK MID LEVEL TROUGH S OF THE GULF OF PANAMA IS SETTING OFF SCATTERED/MODERATE ISOLATED STRONG CONVECTION WITHIN 60 NM S OF THE ITCZ E OF 79W. AT THE SURFACE...A TROUGH EXTENDING FROM 10N117W TO 2N115W IS MOVING W NEAR 15 KT. THE TROUGH IS ENHANCING CONVECTION N OF THE ITCZ WITHIN 120 NM E OF THE TROUGH. STRONG HIGH PRES BUILDING SE IS PRESENT TO THE N OF 16N AND W OF 116W. THE PRES GRADIENT TO THE S OF THE RIDGE IS SUPPORTING NE-E TRADES OF 20-25 KT OVER AN AREA FROM N OF 5N AND W OF 130W...AND FROM 18N-26N BETWEEN 122W-130W. THE RIDGE WILL SHIFT SOUTHWARD OVER N WATERS DURING THE FEW DAYS ALLOWING FOR THE AREA OF TRADES TO DIMINISH. FRESH TO STRONG NW WINDS ARE PRESENT E OF THE RIDGE IN THE FAR NE WATERS OF THE AREA ALONG THE COAST OF BAJA CALIFORNIA PENINSULA. THESE WINDS ARE FORECAST TO LAST UNTIL EARLY SAT. A COLD FRONT WELL TO THE N OF THE DISCUSSION ASSOCIATED WITH A DEVELOPING VIGOROUS UPPER LEVEL LOW IS FORECAST TO QUICKLY SWEEP SE ACROSS THE NW WATERS ON SAT PRECEDED AND FOLLOWED BY INCREASING WINDS. LARGE N-N SWELLS OVER MOST OF THE AREA N OF 5N W OF 130W...AND FROM 18N-26N BETWEEN 122W-130W WILL SLOWLY SUBSIDE THROUGH LATE FRI. HOWEVER...A NEW SET OF LARGE SWELLS IS FORECAST TO SPREAD SE INTO THE NORTHERN AND CENTRAL PORTIONS ON SAT AS THIS NEW SYSTEM MAKES HEADWAY INTO THE REGION. GAP WINDS... GULF OF TEHUANTEPEC...N WINDS WILL CONTINUE TO FUNNEL THROUGH THE ISTHMUS OF TEHUANTEPEC THROUGH THE FORECAST PERIOD BETWEEN HIGH PRES OVER EASTERN MEXICO AND LOWER PRES SE OF TEHUANTEPEC. WINDS WILL PULSE TO 25 KT IN THE MORNING HOURS WHEN DRAINAGE FLOW THROUGH THE ISTHMUS WILL BE AT ITS DIURNAL MAXIMUM. GULF OF PAPAGAYO...NE TO E WINDS OF 20-25 KT AS REPORTED BY SHIPS "A8FZ6" AND "9V8797" DOWNWIND OF THE GULF WILL CHANGE LITTLE OVER THE NEXT 48 HOURS AS THE PRES GRADIENT REMAINS RELATIVELY STRONG BETWEEN HIGHER PRES TO THE N AND LOWER PRES TO THE S OF PAPAGAYO. GULF OF PANAMA...A STRONG PRES GRADIENT HAS BECOME EVIDENT BETWEEN THE COLOMBIAN LOW AND HIGH PRES OVER CENTRAL AMERICA. THIS WILL RESULT IN N WINDS OF 20 KT TO INCREASE TO 20-25 KT IN 24 HOURS AS THEY EXTEND TO 4N BETWEEN 78W-81W THEN DECREASE BY EARLY SAT MORNING. $$ AGUIRRE