000 AXPZ20 KNHC 221605 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1605 UTC THU MAY 22 2014 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1500 UTC. ...SPECIAL FEATURES... DEVELOPING LOW PRES NEAR 11N107W 1008 MB IS SHIFTING SLOWLY WNW THIS MORNING. SATELLITE IMAGERY THIS MORNING SHOWED BANDING FEATURES DEVELOPING ACROSS THE E SEMICIRCLE OF THE LOW...AND HAVE PERSISTED FOR OVER 12 HOURS...ALLOWING FOR DVORAK CLASSIFICATIONS TO COMMENCE. SCATTERED TO LOCALLY NUMEROUS MODERATE TO STRONG CONVECTION WERE OCCURRING IN CLUSTERS AND SHORT BANDS WITHIN 330 NM E SEMICIRCLE...WHILE ISOLATED TO SCATTERED MODERATE TO STRONG CONVECTION WAS OCCURRING WITHIN 330 NM W SEMICIRCLE. OVERNIGHT ASCAT PASSES DID NOT SAMPLE THE CORE CIRCULATION OF THIS LOW...AND SHOWED WEAK WINDS 15 KT OR LESS ON THE PERIPHERY. UPPER LEVEL CONDITIONS ARE FAVORABLE FOR CONTINUED DEEP CONVECTION NEAR THIS SYSTEM IN THE SHORT TERM. WHILE SATELLITE IMAGERY SUGGESTS THAT THIS SYSTEM IS SLOWLY GAINING SOME ORGANIZATION...THIS HAS NOT LIKELY BEGUN TO MANIFEST AT THE SURFACE. GLOBAL MODELS SUGGEST THAT THIS LOW WILL MOVE SLOWLY W-NW TO NW OVER THE NEXT FEW DAYS AND COULD IMPROVE IN ORGANIZATION. THIS SYSTEM HAS A MEDIUM CHANCE FOR DEVELOPING INTO A TROPICAL CYCLONE DURING THE NEXT 5 DAYS. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... MONSOON TROUGH EXTENDS FROM LOW PRES ALONG COLOMBIA COAST NEAR 10N75.5W 1010 MB TO 08N79W TO 10N86W TO 06.5N95W TO DEVELOPING LOW PRES NEAR 11N107W 1008 MB TO LOW PRES NEAR 14N117.5W 1011 MB....WHERE THE TROUGH TERMINATES. ITCZ THEN BEGINS FROM 11.5N119W TO BEYOND 07.5N140W. SCATTERED MODERATE TO STRONG CONVECTION NOTED WITHIN 270 NM S OF THE MONSOON TROUGH BETWEEN 88W AND 101W. SCATTERED MODERATE CONVECTION NOTED WITHIN 120 NM N AND 240 NM S OF ITCZ W OF 125W. ...DISCUSSION... IN THE UPPER LEVELS... AN UPPER LEVEL TROUGH EXTENDS ACROSS NE PORTIONS OF THE AREA FROM AN UPPER CYCLONE CENTERED OVER S NEVADA AND SE CALIFORNIA SOUTHWARD ALONG 116-117W TO A BASE ALONG 19N. A SECOND UPPER TROUGH EXTENDS FROM 28N131W TO NEAR 17N150W. WESTERLY WINDS IN THE UPPER LEVELS UNDULATE S OF THESE TROUGHS AND UPPER LEVEL RIDGING PREVAILING OVER CONVECTION OCCURRING ALONG THE MONSOON TROUGH AND ITCZ. A WEAK UPPER RIDGE IS NOTED S OF 12N BETWEEN 123W AND 136W...WITH A BROAD UPPER RIDGE IS CENTERED ON AN ANTICYCLONE NEAR 13N99W AND EXTENDS N ACROSS ERN MEXICO AND INTO THE LOWER MS RIVER VALLEY. UPPER LEVEL DIVERGENCE OCCURRING ON THE WRN PERIPHERY OF THIS SECOND RIDGE IS AIDING IN PRODUCING SUSTAINED DEEP CONVECTION NEAR THE DEVELOPING LOW PRES SYSTEM ALONG 11N107W. ON THE SURFACE... A 1025 MB HIGH IS CENTERED NEAR 33N135W WITH RIDGE EXTENDING SE TO NEAR 22N110W. THE PRES GRADIENT BETWEEN THE RIDGE AND LOW PRES ACROSS MEXICO IS PRODUCING NNW WINDS 15-20 KT ALONG THE W COAST OF BAJA CALIFORNIA...WHERE SEAS ARE RUNNING 5 TO 6 FT IN MIXED NW AND SW SWELL. S OF THE RIDGE...THE PRES GRADIENT N OF THE ITCZ WAS PRODUCING A ZONE OF 15-20 KT NE TRADEWINDS GENERALLY S OF 20N AND W OF 125W...WHERE SEAS WERE 6 TO 7 FT...AND 20-25 KT FROM 04.5N TO 08.5N W OF 139W...WHERE SEAS WERE 8-9 FT. THE RIDGE WILL GENERALLY REMAIN IN PLACE THROUGH SAT THEN BEGIN TO WEAKEN AND DRIFT W SUNDAY. THE GENERAL PATTERN AND CONDITIONS ARE THEREFORE NOT EXPECTED TO CHANGE MUCH THROUGH SAT. WEAK MONSOONAL FLOW DOMINATES THE AREA E OF 110W...WHERE AMPLE TROPICAL MOISTURE IS CONVERGING ALONG THE MONSOON TROUGH. THE UPPER TROUGH ACROSS SRN CALIFORNIA IS EXPECTED TO FLATTEN DURING THE NEXT FEW DAYS TO MAINTAIN FAVORABLE CONDITIONS FOR DEEP CONVECTION ACROSS THIS AREA E OF 115W. $$ STRIPLING