000 WTPZ42 KNHC 250846 TCDEP2 TROPICAL STORM RAYMOND DISCUSSION NUMBER 22 NWS NATIONAL HURRICANE CENTER MIAMI FL EP172013 200 AM PDT FRI OCT 25 2013 THE INTENSITY OF RAYMOND IS SOMEWHAT UNCERTAIN TONIGHT. WHILE SATELLITE IMAGERY CONTINUES TO SHOW A LARGE AREA OF DEEP CONVECTION NEAR THE ESTIMATED CENTER LOCATION...A PAIR OF ASCAT PASSES BETWEEN 04Z AND 05Z INDICATE THAT RAYMOND IS WEAKER THAN WOULD BE SUGGESTED BY A BLEND OF THE LATEST SATELLITE CLASSIFICATIONS. THE HIGHER OF THE TWO ASCAT PASSES SHOWED ONLY A FEW 35-40 KT WIND BARBS EAST OF THE CENTER...AND BASED ON THESE DATA THE INTENSITY IS SET TO 45 KT FOR THIS ADVISORY. DESPITE THE WEAKER INITIAL INTENSITY... CONDITIONS STILL APPEAR FAVORABLE FOR STRENGTHENING DURING THE NEXT 2 TO 3 DAYS...AS RAYMOND WILL BE MOVING OVER SUFFICIENTLY WARM WATERS IN A LIGHT SHEAR ENVIRONMENT. THE NHC FORECAST IS A LITTLE LOWER THAN THE PREVIOUS ONE TO ACCOUNT FOR THE CURRENT INTENSITY... BUT STILL SHOWS RAYMOND REACHING HURRICANE STATUS IN A COUPLE OF DAYS. BY DAYS 4 AND 5 RAYMOND WILL MOVE OVER COOLER WATERS AND SHEAR WILL INCREASE AHEAD OF A MID/UPPER-LEVEL TROUGH DIGGING SOUTHWARD OFF THE U.S. WEST COAST...WHICH SHOULD LEAD TO WEAKENING. THROUGH THE PERIOD...THE NHC FORECAST IS CLOSE TO THE IVCN INTENSITY CONSENSUS AID. THE CENTER OF RAYMOND HAS BEEN DIFFICULT TO LOCATE IN GEOSTATIONARY IMAGERY. HOWEVER...MICROWAVE IMAGERY AND THE AFOREMENTIONED ASCAT PASSES SUGGEST THAT THE CENTER IS LOCATED A LITTLE SOUTH OF PREVIOUS ESTIMATES WITH A SOMEWHAT UNCERTAIN INITIAL MOTION OF 260/09. THE TRACK FORECAST SCENARIO HAS NOT CHANGED IN THE SHORT TERM...AND THE GUIDANCE REMAINS IN GENERALLY GOOD AGREEMENT THAT RAYMOND WILL MOVE WESTWARD TO THE SOUTH OF A MID-LEVEL RIDGE FOR THE NEXT 48 HOURS. DURING THIS TIME...THE NHC TRACK IS CLOSE TO THE MIDDLE OF THE GUIDANCE ENVELOPE AND THE TVCE CONSENSUS...BUT A LITTLE SOUTH OF THE PREVIOUS OFFICIAL FORECAST DUE TO THE ADJUSTMENT IN INITIAL POSITION AND MOTION. LATER IN THE PERIOD THE TRACK FORECAST UNCERTAINTY INCREASES...WITH LARGE RUN-TO-RUN VARIABILITY SEEN IN THE MODELS WITH THE EVOLUTION OF THE ABOVE-MENTIONED MID/UPPER-LEVEL TROUGH. THE LATEST RUNS OF THE ECMWF AND GFS MOVE THIS TROUGH EASTWARD MORE QUICKLY AND RECURVE RAYMOND AHEAD OF THE TROUGH BY DAY 5. GIVEN THE LACK OF CONSISTENCY IN THE GLOBAL MODEL SOLUTIONS...AND THE EXPECTATION THAT RAYMOND WILL BE A SHALLOWER SYSTEM BY THE END OF THE PERIOD...I HAVE ADJUSTED THE TRACK ONLY A LITTLE TO THE RIGHT AT DAYS 3 THROUGH 5 TO MAINTAIN CONTINUITY WITH THE PREVIOUS NHC FORECAST. THE NHC TRACK AT THESE TIMES IS MUCH SLOWER THAN THE CONSENSUS AND IS CLOSE TO THE GEFS ENSEMBLE MEAN ON THE LEFT SIDE OF THE GUIDANCE ENVELOPE. FORECAST POSITIONS AND MAX WINDS INIT 25/0900Z 14.2N 108.5W 45 KT 50 MPH 12H 25/1800Z 13.9N 110.0W 50 KT 60 MPH 24H 26/0600Z 13.5N 112.2W 55 KT 65 MPH 36H 26/1800Z 13.4N 114.4W 60 KT 70 MPH 48H 27/0600Z 13.4N 116.4W 65 KT 75 MPH 72H 28/0600Z 14.5N 119.0W 65 KT 75 MPH 96H 29/0600Z 16.5N 119.5W 55 KT 65 MPH 120H 30/0600Z 18.0N 119.0W 40 KT 45 MPH $$ FORECASTER BRENNAN