000 WTPZ45 KNHC 102040 TCDEP5 TROPICAL STORM ODILE DISCUSSION NUMBER 3 NWS NATIONAL HURRICANE CENTER MIAMI FL EP152014 200 PM PDT WED SEP 10 2014 Odile is currently showing the effects of about 15 kt of northeasterly vertical wind shear, with the low-level center partly exposed on the northeastern edge of the main area of convection. Satellite intensity estimates remain 45 kt from TAFB and 30 kt from SAB. Based on these data, the initial intensity remains a possibly conservative 35 kt. The initial motion is 320/5. The various large-scale models suggest that Odile will be caught in an area of weak steering currents for the next 2-3 days, with a slow and erratic motion expected during this time. After that, a mid-level ridge north of the cyclone should strengthen some and steer the cyclone toward the northwest at a faster forward speed. There are two notable changes to the guidance since the last advisory. First, most of the guidance suggests a westward or southwestward motion during the first 36 hours or so. Second, the overall guidance envelope has shifted to the left. This includes the latest ECMWF model, which forecasts a track farther from the coast of Mexico than its previous run. The new forecast track is shifted to the left in response to these changes, although it lies to the right of the center of the guidance envelope. It should be noted that the GFDL and HWRF models are still to the right of the new forecast, showing a track close to mainland Mexico. Odile is expected to remain in an area of moderate shear for the next 24 hours or so, after which the large-scale models suggest the shear should diminish. This should allow at least steady strengthening until the cyclone reaches colder water near the end of the forecast period. An alternative forecast scenario, supported by the SHIPS and GFS models, is that Odile undergoes rapid intensification after 24-36 hours when the shear diminishes. The new intensity forecast shows an increased intensity after 36 hours in best general agreement with the intensity consensus. However, it is well below the SHIPS model, which forecasts Odile to be a major hurricane by 72 hours. A tropical storm watch could be needed for a portion of the coast of southwestern Mexico tonight. Regardless, locally heavy rains are possible across that area later this week. FORECAST POSITIONS AND MAX WINDS INIT 10/2100Z 15.3N 103.2W 35 KT 40 MPH 12H 11/0600Z 15.5N 103.4W 45 KT 50 MPH 24H 11/1800Z 15.7N 103.7W 55 KT 65 MPH 36H 12/0600Z 15.8N 103.9W 65 KT 75 MPH 48H 12/1800Z 16.2N 104.3W 75 KT 85 MPH 72H 13/1800Z 17.5N 105.5W 85 KT 100 MPH 96H 14/1800Z 20.5N 108.5W 90 KT 105 MPH 120H 15/1800Z 24.0N 112.0W 90 KT 105 MPH $$ Forecaster Beven