000 AXPZ20 KNHC 220946 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1005 UTC MON SEP 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0945 UTC. ...SPECIAL FEATURES... TROPICAL DEPRESSION POLO LOCATED AT 22.5N 113.8W OR ABOUT 250 MILES W OF THE SOUTHERN TIP OF BAJA CALIFORNIA PENINSULA AT 0900 UTC SEP 22. THE MINIMUM CENTRAL PRESSURE IS ESTIMATED AT 1005 MB. POLO IS MOVING W OR 270 DEG AT 07 KT...AND IS EXPECTED TO CONTINUE ON THIS TRACK TODAY BUT SLOW...THEN A TURN TO THE SW IS EXPECTED ON TUE. MAXIMUM SUSTAINED WINDS ARE CURRENTLY ARE AT 30 KT WITH GUSTS TO 40 KT. THE CENTER IS EXPOSED WITH INTERMITTENT MODERATE CONVECTION FLARING WELL TO W WITHIN 45 NM OF 23N116W. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS ALSO OBSERVED IN A BAND WELL TO THE NE ACROSS THE BAJA CALIFORNIA PENINSULA WITHIN 30 NM EITHER SIDE OF A LINE FROM 25N112W TO 24N111W. POLO IS EXPECTED TO WEAKEN TO A REMNANT LOW PRESSURE CENTER LATER TODAY SURROUNDED BY STRATOCUMULUS CLOUDS...AND GRADUALLY SPIN DOWN OVER THE NEXT FEW DAYS. SEE THE LATEST PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS MIATCPEP2/WTPZ32 KNHC AND FORECAST ADVISORY UNDER HEADERS MIATCMEP2/WTPZ22 KNHC FOR ADDITIONAL DETAILS. A 1008 MB SURFACE LOW PRESSURE IS EMBEDDED IN THE MONSOON TROUGH NEAR 11.5N96W...AND IS EXPECTED TO MOVE WESTWARD ABOUT 10 KT TO NEAR 14N99W TONIGHT...AND NEAR 13N102W ON TUE NIGHT...WITH THE POSSIBILITY OF TROPICAL CYCLONE FORMATION THROUGHOUT. THE OFFICIAL GRIDS DEPICTS WINDS INCREASING TO 20-25 KT...SEAS TO 8 FT...WITHIN 90 NM OF THE LOW ON THU NIGHT...WITH THE LOW THEN TURNING MORE NW WITH THE 20-25 KT WIND FIELD EXPANDING OUT TO ABOUT 180 NM OVER THE E SEMICIRCLE DURING THE UPCOMING WEEKEND. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS W ACROSS THE SOUTHERN CARIBBEAN BETWEEN 10-11N FROM THE NW COAST OF COLOMBIA TO ACROSS COSTA RICA TO THE PACIFIC COAST OF COSTA RICA AT 10N85W...CONTINUES W TO AN EMBEDDED SURFACE LOW PRESSURE NEAR 11.5N96W 1008 MB. SCATTEROMETER WINDS INDICATE THE MONSOON TROUGH RESUMES FROM 13N123W TO BEYOND 09N140W. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS OBSERVED FROM 01-07N TO THE E OF 80W...AND WITHIN 180 NM EITHER SIDE OF A LINE FROM 08N84W TO 13N97W TO 08N104W TO 06N115W. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS ALSO OBSERVED OVER AND WITHIN 120 NM W OF THE COAST OF GUATEMALA AND MEXICO FROM 90-100W. ...DISCUSSION... A 1017 MB HIGH PRESSURE IS QUASI-STATIONARY NEAR 27N136W WITH ITS ANTICYCLONIC ENVELOPE DOMINATING THE MARINE AREA W OF 120W AND TO THE N OF THE MONSOON TROUGH WITH GENERALLY NE-E 10-15 KT TRADES ACROSS THE TROPICS W OF 120W. A WEAK COLD FRONT IS DISSIPATING FROM 32N133W TO 29N139W. A SECONDARY NORTHWESTERLY 15 KT SURGE WILL PUSH A SECOND COLD FRONT INTO THE FAR NW WATERS LATE TUE...REACHING FROM 32N129W TO 25N140W LATE WED AS NW-N WINDS INCREASE TO 15 KT W OF THE FRONT. THE FRONT WILL DISSIPATE FROM THE EXTREME NORTHERN BAJA CALIFORNIA PENINSULA TO 26N130W LATE THU. NW WINDS WILL INCREASE TO 15-20 KT ALONG THE PACIFIC COAST OF THE BAJA PENINSULA TO THE N OF 30N LATE THU...THEN SPREAD AS FAR S AS 26N BY LATE FRI. SEAS WILL BUILD TO 6-9 FT IN MIXING NW AND SE SWELL ACROSS THE WATERS N OF 26N WITHIN 120 NM W OF THE BAJA PENINSULA ON FRI AND SAT. $$ NELSON