Issued at 500 AM EDT Wed Aug 20 2025
000 WTNT45 KNHC 200852 TCDAT5 Hurricane Erin Discussion Number 36 NWS National Hurricane Center Miami FL AL052025 500 AM EDT Wed Aug 20 2025 The last center fix of an earlier Air Force Reserve Hurricane Hunter mission found that Erin's central pressure had dropped by a few millibars to 954 mb. Although satellite intensity estimates have increased slightly over the past 6 hours, there is no firm evidence to indicate that the pressure drop has translated into stronger maximum winds, which are being held at 85 kt. A recent AMSR2 microwave pass revealed that the hurricane has an small inner eyewall extending about 15 n mi from the center with a pronounced outer ring of convection extending 70-90 n mi from the center. Another reconnaissance mission is scheduled to investigate Erin in a few hours and should be able to help ascertain if the winds have increased. Erin is moving north-northwestward, or 345/11 kt, but it is likely to turn northward very soon. The track guidance is in very good agreement during Erin's expected recurvature over the western Atlantic between the east coast of the U.S. and Bermuda, and no significant changes were made to the first 24-36 hours of the forecast. After 36 hours, there has been a notable increase in forward speed among the models when Erin becomes embedded in the mid-latitude westerlies, and the NHC forecast has been adjusted accordingly. These changes are most evident at days 4 and 5, with the new day 5 position about 600 n mi northeast of the previous day 5 forecast point. Warm waters, relatively light shear, and upper-level divergence could support some intensification over the next 36 hours or so. However, it is unclear if Erin's broad structure will support much increase of the maximum winds, despite the global models showing the central pressure falling further into the 940s mb. The NHC intensity forecast is closest to the HCCA consensus aid, showing some slight strengthening through Thursday. A substantial increase in shear is likely to induce weakening by 48 hours, and Erin is expected to become post-tropical by day 4. It should be noted that the 34- and 50-kt wind speed probabilities in the text and graphical products are likely underestimating the risk of those winds occurring. This is because the forecast wind field of Erin is considerably larger than average compared to the wind field used to derive the wind speed probability product. 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 or tonight. The storm surge will be accompanied by large waves, leading to significant beach erosion and overwash, making some roads impassible. Tropical storm conditions are possible on Thursday along the southeastern coast of Virginia. 3. Tropical storm conditions are possible on Bermuda on Thursday and Friday. 4. Interests elsewhere along the U.S. Mid-Atlantic and southern New England coasts, and Atlantic Canada, should also monitor the progress of Erin as strong winds are possible Thursday through Saturday. FORECAST POSITIONS AND MAX WINDS INIT 20/0900Z 28.9N 73.3W 85 KT 100 MPH 12H 20/1800Z 30.6N 73.5W 90 KT 105 MPH 24H 21/0600Z 33.0N 72.8W 95 KT 110 MPH 36H 21/1800Z 35.4N 70.6W 95 KT 110 MPH 48H 22/0600Z 37.4N 67.3W 90 KT 105 MPH 60H 22/1800Z 39.3N 63.1W 85 KT 100 MPH 72H 23/0600Z 41.0N 57.7W 75 KT 85 MPH 96H 24/0600Z 45.8N 43.9W 65 KT 75 MPH...POST-TROP/EXTRATROP 120H 25/0600Z 51.1N 30.8W 55 KT 65 MPH...POST-TROP/EXTRATROP $$ Forecaster Berg