000 AXPZ20 KNHC 070942 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1005 UTC TUE AUG 07 2012 TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM THE EQUATOR TO 32N...EAST OF 140W. THE FOLLOWING INFORMATION IS BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND METEOROLOGICAL ANALYSIS. BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0845 UTC. ...SPECIAL FEATURES... THE LOW PRESSURE SYSTEM LOCATED WELL SOUTHWEST OF THE MEXICAN COAST IS UPGRADED TO TROPICAL DEPRESSION SEVEN-E AT 07/0900 UTC. AT THIS TIME...IT IS CENTERED NEAR 14.3N 111.7W MOVING WNW OR 295 DEGREES AT 9 KT. THIS GENERAL MOTION IS EXPECTED TO CONTINUE OVER THE NEXT COUPLE OF DAYS. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1007 MB. MAXIMUM SUSTAINED WIND SPEED IS 30 KT WITH GUSTS TO 40 KT. STRENGTHENING IS FORECAST DURING THE NEXT 48 HOURS...AND THE DEPRESSION COULD BECOME A TROPICAL STORM LATER TODAY. PLEASE SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP2/WTPZ22 KNHC FOR MORE DETAILS. NUMEROUS MODERATE TO STRONG CONVECTION IS NOTED WITHIN 45 NM OF CENTER. SCATTERED MODERATE ISOLATED STRONG CONVECTION CAN BE FOUND ELSEWHERE FROM 13N TO 16N BETWEEN 110W AND 113W. ...TROPICAL WAVES... A TROPICAL WAVE EXTENDS ALONG 136W FROM 09N TO 17N. THIS TROPICAL WAVE IS MOVING W AROUND 10-15 KT. SCATTERED SHOWERS AND ISOLATED TSTMS ARE NOTED ON EITHER SIDE OF THE WAVE AXIS...MORE CONCENTRATED NEAR 14N138W. THE PRES GRADIENT BETWEEN THE SURFACE TROUGHING ASSOCIATED WITH THE WAVE AND THE SUBTROPICAL RIDGE TO THE N SHOULD BE STRONG ENOUGH FOR FRESH TO STRONG WINDS TO BUILD NEAR THE WAVE OVER THE W CENTRAL WATERS DURING THE NEXT FEW DAYS JUST BEFORE IT MOVES W OF THE AREA. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... MONSOON TROUGH AXIS FROM 10N85W TO 1010 MB LOW PRES NEAR 10N100W TO 13N108W THEN CONTINUES W OF T.D. 7E FROM 13N114W TO 09N121W TO 11N130W. ITCZ AXIS FROM 11N130W TO BEYOND 07N140W. SCATTERED MODERATE ISOLATED TO STRONG CONVECTION IS FROM 09N TO 13N BETWEEN 108W AND 114W AND FROM 07N TO 10N BETWEEN 114W AND 122W. ...DISCUSSION... ALOFT...AN ANTICYCLONE OVER ARIZONA EXTENDS A RIDGE SOUTHWARD THROUGH BAJA CALIFORNIA TO NEAR T.D. SEVEN-E. UPPER DIFFLUENCE ASSOCIATED WITH THIS RIDGE IS HELPING TO SUSTAIN THE DEEP CONVECTION ASSOCIATED WITH THIS TROPICAL CYCLONE. W OF THE RIDGE...THERE IS AN UPPER LEVEL LOW SPINNING NEAR 19N123W. THE WEST-CENTRAL PORTION OF THE FORECAST AREA IS DOMINATING BY ANOTHER ANTICYCLONE CENTERED NEAR 19N138W. STRONG SW FLOW AHEAD OF A LONG WAVE TROUGH IS AFFECTING THE FAR NW PART OF THE AREA. NE WINDS ALOFT ARE MAINLY S OF 11N AND E OF 110W. THESE WINDS ARE ENHANCING THE CONVECTION NEAR THE MONSOON TROUGH. A WEAK SUBTROPICAL RIDGE EXTENDS OVER MUCH OF THE AREA N OF 15N W OF 115W. THE RIDGE WILL BUILD IN AS A NEW HIGH PRES CELL DEVELOPS NEAR 35N140W IN ABOUT 24 HOURS. THEN...THE SUBTROPICAL HIGH WILL SLOWLY BEGIN TO WEAKEN WED AS A COLD FRONT APPROACHES THE HIGH FROM THE NW. NE WINDS OF 15 TO 20 KT ARE BLOWING AROUND THE SOUTHERN PERIPHERY OF THE RIDGE BUT ARE EXPECTED TO INCREASE TO 20-25 KT NEAR THE TROPICAL WAVE ALONG 135W LATER TODAY OR TONIGHT. GAP WINDS...FRESH TO STRONG NORTHERLY WINDS WILL CONTINUE TO FUNNEL THROUGH CHIVELA PASS INTO THE GULF OF TEHUANTEPEC THROUGH WED MORNING. THIS GAP WIND EVENT WAS INDUCED BY THE PRESSURE GRADIENT BETWEEN RELATIVELY HIGHER SURFACE PRESSURES OVER THE SW GULF OF MEXICO AHEAD OF ATLANTIC TROPICAL STORM ERNESTO AND LOWER PRESSURE WITH THE MONSOON TROUGH SOUTH OF TEHUANTEPEC WHICH WILL BE DRIFTING NORTHWARD BEFORE ERNESTO MOVES INTO THE YUCATAN PENINSULA LATE TONIGHT. $$ GR