000 WTPZ45 KNHC 060249 TCDEP5 TROPICAL STORM ERICK DISCUSSION NUMBER 7 NWS NATIONAL HURRICANE CENTER MIAMI FL EP052013 800 PM PDT FRI JUL 05 2013 ALTHOUGH THE HINT OF AN EYE OBSERVED EARLIER IN CONVENTIONAL IMAGERY IS NOT DISCERNIBLE AT THIS TIME...LATEST MICROWAVE DATA SHOW A WELL DEFINED RING OF CONVECTION WHICH NORMALLY LEADS THE FORMATION OF AN EYE. A BLEND OF OBJECTIVE AND SUBJECTIVE DVORAK ESTIMATES INDICATE THAT ERICK IS NOT A HURRICANE YET AND THE INITIAL INTENSITY REMAINS AT 60 KNOTS. HOWEVER...GIVEN THE STRUCTURE OBSERVED ON IR AND MICROWAVE IMAGERY...ERIC COULD BECOME A HURRICANE AT ANY TIME SOON. THE INTENSITY GUIDANCE ONLY SUGGESTS A MODEST STRENGTHENING DURING THE NEXT 24 HOURS AND SO DOES THE OFFICIAL FORECAST. BEYOND 36 HOURS...A PORTION OF THE CIRCULATION WILL BEGIN TO APPROACH COOLER WATERS AND A GRADUAL WEAKENING SHOULD BEGIN. ERICK IS MOVING TOWARD THE NORTHWEST OR 315 DEGREES AT 9 KNOTS AND THIS BASED ON MICROWAVE FIXES. SOME OF THE TRACK MODELS...PRIMARILY THE GFS...HAVE SHIFTED A LITTLE BIT TO THE RIGHT IN THE LAST RUN. IN FACT...THE GFS MADE A BIG CHANGE IN THE 1800 UTC RUN AND NOW HAS ERICK MOVING INLAND OVER SOUTHWESTERN MEXICO IN ABOUT 24 HOURS. THE OFFICIAL FORECAST WAS ADJUSTED SLIGHTLY EASTWARD DURING THE NEXT 24 TO 36 HOURS BUT NOT AS FAR EAST AS INDICATED BY THE GFS...AND IN BETTER AGREEMENT WITH THE ECMWF AND THE FLORIDA STATE SUPERENSEMBLE. THIS MEANS THAT THE CORE OF THE CYCLONE IS NOW FORECAST TO MOVE A LITTLE BIT CLOSER TO THE COAST OF MEXICO. BEYOND 36 HOURS...ERICK WILL BE SOUTH OF A STRONG MID-LEVEL RIDGE CENTERED OVER THE SOUTHWEST UNITED STATES AND THIS PATTERN WOULD FORCE THE CYCLONE TOWARD THE WEST UNTIL DISSIPATION. SINCE THE 34-KNOT WIND RADII WAS EXPANDED IN THE NORTHEAST QUADRANT BASED ON A SHIP REPORT...THE GOVERNMENT OF MEXICO EXTENDED THE TROPICAL STORM WARNING TO CABO CORRIENTES. FORECAST POSITIONS AND MAX WINDS INIT 06/0300Z 16.7N 103.5W 60 KT 70 MPH 12H 06/1200Z 17.5N 104.3W 70 KT 80 MPH 24H 07/0000Z 18.9N 105.5W 70 KT 80 MPH 36H 07/1200Z 20.2N 107.0W 65 KT 75 MPH 48H 08/0000Z 21.4N 108.9W 55 KT 65 MPH 72H 09/0000Z 23.0N 113.0W 30 KT 35 MPH 96H 10/0000Z 23.0N 117.5W 25 KT 30 MPH...POST-TROP/REMNT LOW 120H 11/0000Z 23.0N 122.5W 20 KT 25 MPH...POST-TROP/REMNT LOW $$ FORECASTER AVILA