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| #983109 (Received by flhurricane at: 4:54 PM 19.Sep.2019) TCDAT5 Hurricane Jerry Discussion Number 10 NWS National Hurricane Center Miami FL AL102019 500 PM AST Thu Sep 19 2019 Jerry is a compact hurricane on satellite imagery with the central dense overcast becoming more symmetric during the past few hours. Before the Air Force plane departed, the crew recorded 700-mb flight-level winds of 97 kt and SFMR winds of about 70 kt, suggesting maximum winds of about 75 kt. Since that time, an eye feature has been noted on the last-light visible images, indicating that the earlier intensification has probably continued. Thus, the initial wind speed is set to 80 kt, and the next aircraft is scheduled to investigate Jerry around 0000 UTC to obtain a better estimate. The hurricane still has some time to strengthen before northwesterly shear increases by tomorrow morning. The shear increase will also probably allow some environmental dry air to be entrained into the central core and help weaken the cyclone. Thus weakening is anticipated by late tomorrow continuing into Saturday. Some re-strengthening is possible early next week as Jerry could find a lower shear region due to a mid-latitude trough interaction. The new NHC wind speed prediction has not changed too much, but is a little higher at longer range to reflect the above possibility. The initial motion is still west-northwestward, or 295/15 kt. A large subtropical ridge to the northeast of Jerry should continue to steer the hurricane at about the same direction and speed during the next day or two. The models have generally trended a bit to the north on this cycle at short range, and the official forecast follows suit. Thereafter, Jerry is forecast to move around the then-weakening ridge, turning to the northwest on Saturday, north-northwest on Sunday, and then northward and north- northeastward by Monday/Tuesday. The guidance has moved to the northeast at longer range on this cycle, possibly due to a stronger mid-latitude trough helping to weaken the ridge. The NHC forecast is adjusted to the northeast on this advisory, although is still on the western side of the guidance envelope. Key Messages: 1. Although the core of Jerry is expected to move north of the northern Leeward Islands, life-threatening flash floods are possible, along with tropical-storm-force winds in some areas. FORECAST POSITIONS AND MAX WINDS INIT 19/2100Z 17.5N 55.8W 80 KT 90 MPH 12H 20/0600Z 18.4N 57.9W 85 KT 100 MPH 24H 20/1800Z 19.5N 60.8W 75 KT 85 MPH 36H 21/0600Z 20.7N 63.6W 70 KT 80 MPH 48H 21/1800Z 21.9N 65.8W 65 KT 75 MPH 72H 22/1800Z 24.9N 68.7W 65 KT 75 MPH 96H 23/1800Z 28.0N 68.5W 65 KT 75 MPH 120H 24/1800Z 33.0N 65.0W 70 KT 80 MPH $$ Forecaster Blake |