000 AXPZ20 KNHC 300925 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 1005 UTC SUN SEP 30 2007 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 0845 UTC. ...SPECIAL FEATURE... TROPICAL STORM JULIETTE NEAR 17.6N 112.6W 1003 MB AT 0900 UTC SEP 30 MOVING NW OR 325 DEG AT 9 KT. MAXIMUM SUSTAINED WINDS 35 KT GUSTS TO 45 KT. SOLID AREA OF STRONG CONVECTION ON THE W SIDE OF JULIETTE. THE STORM REMAINS IN A ENVIRONMENT OF DEEP MOISTURE. LATEST WATER VAPOR IMAGERY SHOWS STRONG HIGH LEVEL ELY WINDS S OF THE STORM AND SWLY WINDS TO THE NW. A LARGE MID LEVEL TROUGH IS ALONG 127W AND WILL MOVE THE STORM ON A NW AND N TRACK DURING THE NEXT 24 HR. ...TROPICAL WAVES... TROPICAL WAVE ALONG 88W N OF 3N MOVING W 10-15 KT. SCATTERED CONVECTION OFF THE COAST OF COSTA RICA AND PANAMA BUT NO ORGANIZATION. WEAK TROPICAL WAVE ALONG 125W S OF 15N MOVING W 10 KT. THERES NO EVIDENCE OF THIS WAVE. THE UPPER ATMOSPHERE IS BECOMING INCREASINGLY DRIER. ...ITCZ... INTERTROPICAL CONVERGENCE ZONE...AXIS 9N80W 9N92W 16N104W 15N115W 10N125W 10N140W. ISOLATED AREAS OF MODERATE CONVECTION NEAR 8N92W 10N95W 10N101W 12N103W AND 13N108W. AREA OF SCATTERED MODERATE CONVECTION FROM 10N TO 14N BETWEEN 114W AND 120W. SCATTERED MODERATE TO STRONG CONVECTION WITHIN 60 NM OF THE COAST OF CENTRAL AMERICA FROM 7N81W TO 12N89W TO 15N96W TO 15N99W TO 16N102W. SCATTERED MODERATE WITHIN 60 NM OF 22N109W. ...DISCUSSION... A STRONG UPPER TROUGH HAS LEFT IT'S MARK TONIGHT ALONG 120W S OF 30N AS A POOL OF VERY DRY COOL AIR SANK SWD. THE MAIN ENERGY IN THE TROUGH IS MOVING E TONIGHT OVER THE CENTRAL ROCKIES WHILE A LARGE DETACHED TROUGH CONTINUES OVER OUR REGION BETWEEN 115W AND 130W. ON THE SURFACE TONIGHT T.S. JULIETTE IS NEAR 16.5N112W MOVING NNW AT 7 KT. THE LATEST WATER VAPOR IMAGERY SHOWS JULIETTE IS EMBEDDED IN DEEP MOIST ATMOSPHERE AND IT'S OUTFLOW IS ENHANCED BY SWIFT E WINDS TO THE S AND SW WINDS ON IT'S WRN SIDE. THE PACIFIC RIDGE WITH A 1021 MB HIGH CENTER NEAR 33N131W IS PRODUCING NE TRADES TO 20 KT W OF 120W ACCORDING TO SSMI. NO PASS FROM QUIKSCAT. WINDS ALONG THE BAJA COAST HAVE PICKED UP WITH SSMI SHOWING NLY 15 TO 20 KT. GAP WINDS LIGHT TONIGHT BUT CROSS EQUATORIAL SLY WINDS STRONGEST S OF 13N BETWEEN 108W AND 124W ENHANCED BY THE PRESENCE OF JULIETTE TO THE N. LATER DAY 1 A STRONG BLOCKING RIDGE LIES OVER THE SRN CONUS AND EXTENDS WWD TO NEAR 120W. THIS IS HOLDING THE TROUGH ALONG 125W IN POSITION. ANOTHER SURGE IS NOTED NNW OF THE AREA AND MAY HAVE SOME AFFECT ON THE TROUGH. ON THE SURFACE LATER DAY 1 JULIETTE FORECAST TO CONTINUE NW BUT WILL SOON TAP INTO THE VERY DRY ATMOSPHERE TO IT'S NW AND BEGIN TO WEAKEN. THE PACIFIC RIDGE WILL REMAIN WEAK OVER OUR REGION WITH NE TRADES 10 TO 15 KT. BAJA WINDS COULD INCREASE ALONG THE SRN PORTION OF THE PENINSULA AS JULIETTE APPROACHES FROM THE SW. GAP WINDS THROUGH TEHUANTEPEC INCREASE SOME AS STRONG HIGH PRES OVER THE NE GULF PUMPS AIR SW INTO THE BAY OF CAMPECHE. CROSS EQUATORIAL SLY WINDS REMAIN STRONGEST BETWEEN 108W AND 125W MAINLY DUE TO THE PRESENCE OF JULIETTE TO THE N. FOR DAY 2 THE GFS MODEL SHOWS THE NEXT FAIRLY STRONG SHORTWAVE MOVING ESE INTO THE CA COAST. THE OLD TROUGH ALONG 125W TRIES TO ESCAPE BUT THE STRONG BLOCKING RIDGE TO THE E SHIFTS WWD OVER THE SRN PLAINS AND WILL HAVE NONE OF IT. ANOTHER MID LEVEL RIDGE APPEARS NW OF THE AREA AND SHOULD ENHANCE THE SURFACE PACIFIC RIDGE. ON THE SURFACE DAY 2 THE PACIFIC RIDGE DOES INDEED STRENGTHEN ACCORDING TO THE GFS MODEL BUT WINDS ARE SLOW TO INCREASE. JULIETTE WEAKENING AS IT TURNS NWD OFF THE SW COAST OF THE BAJA AND WINDS INCREASE ALONG THE BAJA COAST WITH SLY SWELL. GAP WINDS MOSTLY LIGHT EXCEPT FOR TEHUANTEPEC WHERE THE MODEL SHOWS 20 KT. CROSS EQUATORIAL SLY WINDS INCREASE SOME E OF 105W TO 20 KT WITH LOWERING PRES ALONG 10N E OF 95W. $$ RRG