000 WTPZ45 KNHC 050256 TCDEP5 TROPICAL STORM ERICK DISCUSSION NUMBER 3 NWS NATIONAL HURRICANE CENTER MIAMI FL EP052013 800 PM PDT THU JUL 04 2013 THE CLOUD PATTERN OF ERICK IS DOMINATED BY A MASS OF COLD-TOPPED DEEP CONVECTION TO THE WEST OF THE CENTER. CONVECTIVE BANDING FEATURES HAVE ALSO INCREASED AND GAINED SLIGHTLY MORE CURVATURE DURING THE LAST FEW HOURS. A PAIR OF RECENT MICROWAVE IMAGES WITHIN INDICATED THAT THE CENTER IS BETTER DEFINED BUT EXPOSED NORTHEAST OF THE NEAREST DEEP CONVECTION. A BLEND OF A SUBJECTIVE DVORAK INTENSITY ESTIMATE FROM TAFB OF T2.5/35 KT...MICROWAVE-ADJUSTED OBJECTIVE DVORAK INTENSITY ESTIMATES FROM UW-CIMSS OF 3.0...AND AN AMSU INTENSITY ESTIMATE IS THE BASIS FOR INCREASING THE INITIAL INTENSITY ESTIMATE TO 40 KT ON THIS ADVISORY. IT DIFFICULT TO ASSESS THE INITIAL MOTION...BUT RECENT FIXES SUGGEST A MOTION ESTIMATE OF 310/10. ERICK IS EXPECTED TO MOVE AROUND THE SOUTHWESTERN PERIPHERY OF A MID-LEVEL RIDGE OVER THE NORTHWESTERN CARIBBEAN SEA AND TOWARD A WEAKNESS OVER CENTRAL MEXICO DURING THE NEXT 48 HOURS OR SO. THE HEADING OF THE CYCLONE SHOULD BEND WEST- NORTHWESTWARD IN 2-3 DAYS IN RESPONSE TO THE HEAT RIDGE OVER THE SOUTHWESTERN UNITED STATES SLIDING EASTWARD. ALTHOUGH THE MODEL GUIDANCE IS IN GOOD AGREEMENT REGARDING THE MAIN SYNOPTIC FEATURES...THERE IS STILL SOME QUESTION ABOUT EXACTLY WHEN THE CHANGE IN TRACK WILL OCCUR. THIS DETAIL TO THE FORECAST HAS IMPLICATIONS ON HOW FAR OFFSHORE ERICK WILL TRACK FROM THE COAST OF SOUTHWESTERN MEXICO. THE NHC TRACK FORECAST IS ADJUSTED SLIGHTLY TO THE RIGHT AND IS BASED PRIMARILY ON THE ECMWF AND THE MULTI-MODEL CONSENSUS. MODERATE EAST-NORTHEASTERLY SHEAR PREVAILS OVER THE STORM... ACCORDING TO THE LATEST SHIPS AND UW-CIMSS ANALYSES. THE SHEAR SHOULD LIMIT THE AMOUNT OF INTENSIFICATION THAT CAN OCCUR DURING THE NEXT 2-3 DAYS...DESPITE FAVORABLE OCEANIC CONDITIONS. WHILE THE UPPER-LEVEL EASTERLIES MAY WEAKEN AFTER THAT TIME...ERICK WILL HAVE LIKELY ALREADY REACHED COOLER WATERS AND A MORE STABLE ENVIRONMENT. THEREFORE...STEADY TO RAPID WEAKENING IS EXPECTED LATE IN THE PERIOD...WITH REMNANT LOW STATUS FOREAST BY DAY 5...IF NOT SOONER. THE INTENSITY FORECAST IS HIGHER THAN THE PREVIOUS ONE IN THE SHORT TERM AS A CONSEQUENCE OF THE LATEST TREND AND IS CLOSE TO THE INTENSITY CONSENSUS AIDS...IVCN AND ICON. GIVEN THE FORECAST TRACK AND WIND RADII...THE GOVERNMENT OF MEXICO HAS ISSUED A TROPICAL STORM WARNING FOR A PORTION OF THE SOUTWESTERN COAST OF MEXICO. FORECAST POSITIONS AND MAX WINDS INIT 05/0300Z 14.9N 100.0W 40 KT 45 MPH 12H 05/1200Z 15.8N 101.0W 45 KT 50 MPH 24H 06/0000Z 16.6N 102.5W 50 KT 60 MPH 36H 06/1200Z 17.4N 103.9W 55 KT 65 MPH 48H 07/0000Z 18.3N 105.6W 55 KT 65 MPH 72H 08/0000Z 19.9N 108.7W 45 KT 50 MPH 96H 09/0000Z 21.2N 112.5W 35 KT 40 MPH 120H 10/0000Z 22.0N 117.0W 30 KT 35 MPH...POST-TROP/REMNT LOW $$ FORECASTER KIMBERLAIN/AVILA