Issued at
000 WTNT45 KNHC 202037 TCDAT5 Hurricane Erin Discussion Number 38 NWS National Hurricane Center Miami FL AL052025 Erin continues to look impressive on satellite imagery, with a fairly symmetric cloud pattern and numerous convective banding features. Upper-level outflow remains well-defined over most parts of the circulation. An AMSR microwave image from just before 18Z showed a concentric eyewall structure with an outer ring of convection at a radius of 70-80 n mi from the center and an inner eyewall at a radius of about 20 n mi. The current intensity estimate is held at 95 kt based on a blend of subjective Dvorak classifications from TAB and SAB and objective intensity estimates from UW-CIMSS. The hurricane is moving northward with a forward speed of around 12 kt. The steering scenario and track forecast reasoning have not changed from the previous advisory. Erin should move around the western and northwestern periphery of a mid-level subtropical anticyclone over the next day or so, moving between Bermuda and the U.S. east coast. After that, the system should accelerate northeastward and east-northeastward while embedded within the mid-latitude westerlies over the north Atlantic. The official forecast is close to the previous NHC prediction and is in good agreement with the NOAA corrected consensus, HCCA, guidance. Although Erin is over warm waters with ample mid- to low-level moisture, The concentric convective ring structure of the system will likely prevent significant strengthening and the official intensity forecast now only shows a slight-short term increase in intensity, similar to the DSHIPS and LGEM guidance. Beginning in about 36 hours, the SHIPS model diagnoses a large increase in vertical wind shear so a weakening trend is anticipated from that time onward. The predicted structure of the cyclone in the global models indicates that extratropical transition should be underway in 3-4 days, while Erin passes over much cooler waters. Erin is an usually large hurricane. For hurricanes north of 30N latitude, its tropical-storm-force wind radii are in the 75th percentile of the Atlantic basin record. KEY MESSAGES: 1. Erin is expected to produce life-threatening surf and rip currents along the beaches of the Bahamas, much of the east coast of the U.S., Bermuda, and Atlantic Canada during the next several days. Beachgoers in those areas should follow advice from lifeguards, local authorities, and beach warning flags. 2. Storm surge flooding and tropical storm conditions are expected in the North Carolina Outer Banks beginning later today and lasting through Thursday. The storm surge will be accompanied by large waves, leading to significant beach erosion and overwash, making some roads impassible. 3. Tropical storm conditions are expected on Thursday along the Virginia coast. Wind gusts to tropical storm force are likely along portions of the remainder of the U.S. Mid-Atlantic and southern New England coasts Thursday through early Friday. 4. Tropical storm conditions are possible on Bermuda on Thursday and Friday. FORECAST POSITIONS AND MAX WINDS INIT 20/2100Z 31.2N 73.6W 95 KT 110 MPH 12H 21/0600Z 33.2N 72.9W 100 KT 115 MPH 24H 21/1800Z 35.5N 70.6W 100 KT 115 MPH 36H 22/0600Z 37.5N 67.3W 95 KT 110 MPH 48H 22/1800Z 39.2N 63.0W 85 KT 100 MPH 60H 23/0600Z 41.0N 57.6W 75 KT 85 MPH 72H 23/1800Z 43.1N 50.8W 55 KT 65 MPH 96H 24/1800Z 49.0N 34.5W 55 KT 65 MPH...POST-TROP/EXTRATROP 120H 25/1800Z 54.0N 23.0W 45 KT 50 MPH...POST-TROP/EXTRATROP $$ Forecaster Pasch