000 AXPZ20 KNHC 132124 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 2205 UTC SAT JUN 13 2009 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 2115 UTC. ...TROPICAL WAVES... TROPICAL WAVE IS ALONG 83W N OF 02N MOVING W 10 KT. A BROAD AREA OF CYCLONIC TURNING...IN PART ASSOCIATED WITH THIS WAVE...IS EVIDENT IN THE MID-LEVEL CLOUDS COVERING THE REGION BETWEEN THE GULF OF HONDURAS AND THE GULF OF TEHUANTEPEC. THE UPPER PATTERN IS HIGHLY DIFFLUENT OVER THIS REGION WHICH IS GENERATING AND SPREADING A FAIR AMOUNT OF CONVECTION (DESCRIBED IN THE ITCZ SECTION BELOW). ...ITCZ... ITCZ AXIS IS ALONG 06N77W TO 09N90W TO 09N110W TO 07N140W. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS FROM 04N TO 10N E OF 89W. SCATTERED MODERATE CONVECTION IS FROM 07N TO 13N BETWEEN 94W AND 102W. SCATTERED MODERATE CONVECTION IS WITHIN 180 NM N OF THE AXIS BETWEEN 104W AND 111W. ...DISCUSSION... A HIGHLY AMPLIFIED RIDGE HAS BEEN NEARLY STATIONARY OVER CENTRAL MEXICO FOR THE PAST COUPLE OF DAYS. UPPER LEVEL DIFFLUENCE ON ITS SE PERIPHERY IS INTERACTING WITH THE TROPICAL WAVE TO GENERATE A LARGE AREA OF CONVECTION AS DESCRIBED ABOVE. THIS RIDGE IS EXPECTED TO SHIFT N AND WEAKEN SLIGHTLY OVER THE NEXT FEW DAYS AS AN UPPER LOW CURRENTLY OVER THE NW CARIBBEAN MOVES W INTO THE EPAC. A MID-UPPER TROUGH EXTENDS WELL INTO THE TROPICS FROM SOUTHERN CALIFORNIA TO 11N131W. DEEP LAYER DRY AIR EXISTS ALONG AND TO THE W OF THE TROUGH AXIS. THIS DRY AIR CONTINUES TO BE ENTRAINED INTO THE REMNANTS OF AN INVEST AREA LOCATED NEAR 16N115W. THIS FORMER INVEST AREA...STILL BE TRACKED AS A 1012 MB LOW...ONLY CONSISTS OF A WEAK CIRCULATION WITH AN AREA OF LOW-MID LEVEL CLOUDS OVER ITS NRN SEMICIRCLE. ATMOSPHERIC LIFT E OF THE UPPER TROUGH IS FORECAST TO SUPPORT WEAK SMALL SCALE SFC LOWS IN THE NORTHERN GULF OF CALIFORNIA DURING THE NEXT COUPLE DAYS...WHICH WILL BE ENHANCED AT NIGHT WHEN NOCTURNAL DRAINAGE FLOW IS MAXIMIZED...PRODUCING SW TO W WINDS NEAR 20 KT OVER THE N PORTION OF THE GULF. OVER THE FAR SW PORTION OF THE REGION... SCATTERED MODERATE CONVECTION IS LOCATED W OF 139W NEAR THE ITCZ AXIS ENHANCED BY UPPER DIFFLUENCE AND A WEAK PERTURBATION WITHIN THE ITCZ. SCATTEROMETER DATA SUGGESTS A SMALL AREA OF 20 KT NE TRADES FROM 10N-18N W OF 132W. THE PRESSURE GRADIENT IS EXPECTED TO REMAIN SIMILAR OVER THIS REGION DURING THE NEXT FEW DAYS AS HIGH PRES STALLS NEAR 29N145W. FARTHER E...A RECENT ASCAT PASS INDICATED NW 20 KT WINDS NEAR THE COAST OF BAJA CALIFORNIA AND LIKELY OVER THE SRN PORTIONS OF THE GULF OF CALIFORNIA. THIS ENHANCED FLOW IS DUE TO THE PRESSURE GRADIENT...BETWEEN THE AFOREMENTIONED HIGH AND LOWER PRES OVER MEXICO...AND TERRAIN VARIATIONS OVER THE BAJA PENINSULA. LITTLE CHANGE IN THIS REGIME IS EXPECTED OVER THE NEXT FEW DAYS. LONG PERIOD S TO SW SWELL ENCOMPASSES THE ENTIRE EASTERN PACIFIC ELEVATING SIGNIFICANT WAVE HEIGHTS TO NEAR OR HIGHER THAN 8 FT OVER MUCH OF THE REGION S OF 14N W OF 90W. A NEW SURGE OF SW SWELL OF 15-17 SECONDS IS FORECAST TO CROSS THE EQUATOR TONIGHT AND REACH THE COASTS OF CENTRAL AMERICA AND MEXICO MON NIGHT AND TUE. $$ CANGIALOSI