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| #1060718 (Received by flhurricane at: 10:54 AM 08.Sep.2021) TCDAT2 Hurricane Larry Discussion Number 32 NWS National Hurricane Center Miami FL AL122021 1100 AM AST Wed Sep 08 2021 Larry`s eye has been only faintly apparent on recent satellite imagery, but the hurricane is still maintaining a fair amount of deep convection near/around the center. An Air Force Reserve Unit Hurricane Hunter aircraft investigated Larry a little while ago and observations found that the central pressure has risen only slightly since yesterday, with peak flight level winds of 118 kt in the northeastern quadrant. However, the highest SFMR-observed surface winds were only 75 kt, indicating that the strong winds aloft are not very effectively being transported to the surface. Given this, along with the slightly-degraded appearance of the system, the current intensity is reduced to 95 kt, which is just a bit above the latest subjective and objective Dvorak estimates. The hurricane is moving northwestward at a slightly faster clip, or 320/11 kt. Over the next 36 to 48 hours, Larry is expected to move around the western periphery of a subtropical high pressure area and pass to the east of Bermuda. Thereafter, the cyclone should accelerate northeastward ahead of a deep-layer trough moving through the northeastern United States and become embedded within the mid-latitude southwesterly flow. This will take Larry near or over southeastern Newfoundland in 60-66 hours and then over the far North Atlantic. The official forecast track has not changed significantly from those in the previous few advisories, and remains close to the dynamical model consensus, TVCA. Larry should remain in an environment of low vertical shear and warm surface waters for the next 36-48 hours. However, the oceanic heat content beneath the hurricane should be gradually decreasing during the next few days. Only slow weakening is forecast, similar to the latest NOAA corrected consensus, HCCA, prediction. In about 72 hours, the global models indicate that Larry will become embedded within a frontal zone, so the NHC forecast shows it as an extratropical cyclone by that time. In 5 days or less, the system is expected to merge with another large cyclone at high latitudes. Key Messages: 1. Large swells generated by Larry will continue to affect the Leeward Islands, portions of the Greater Antilles, the Bahamas and Bermuda. Significant swells will begin to reach the east coast of the United States and Atlantic Canada later today and continue affecting these shores through the end of the week. These swells will likely cause life-threatening surf and rip current conditions, and beachgoers and other interests along these coasts are urged to follow the guidance of lifeguards and local officials this week. 2. The center of Larry is forecast to pass east of Bermuda on Thursday, but given Larry`s large size, tropical storm conditions are expected there there Thursday, along with a risk of coastal flooding. A Tropical Storm Warning is in effect for Bermuda, and interests there should closely monitor the latest forecast updates. 3. Larry is forecast to move near or over portions of southeastern Newfoundland late Friday and Friday night as it undergoes transition to a hurricane-force post-tropical cyclone. There is an increasing risk of impacts from high winds, rainfall, and storm surge in portions of Newfoundland, and interests there should monitor updates to the forecast. FORECAST POSITIONS AND MAX WINDS INIT 08/1500Z 27.7N 58.3W 95 KT 110 MPH 12H 09/0000Z 29.1N 59.6W 95 KT 110 MPH 24H 09/1200Z 31.6N 61.3W 95 KT 110 MPH 36H 10/0000Z 34.7N 61.9W 90 KT 105 MPH 48H 10/1200Z 39.1N 60.4W 85 KT 100 MPH 60H 11/0000Z 44.4N 55.6W 80 KT 90 MPH 72H 11/1200Z 50.5N 49.0W 65 KT 75 MPH...POST-TROP/EXTRATROP 96H 12/1200Z 61.0N 37.0W 60 KT 70 MPH...POST-TROP/EXTRATROP 120H 13/1200Z...MERGED $$ Forecaster Pasch |