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Hurricane Lee Forecast Discussion Number 38
2017-09-27 16:49:45| National Hurricane Center (Atlantic)
Issued at 1100 AM AST Wed Sep 27 2017 000 WTNT44 KNHC 271449 TCDAT4 Hurricane Lee Discussion Number 38 NWS National Hurricane Center Miami FL AL142017 1100 AM AST Wed Sep 27 2017 After an eyewall replacement overnight, satellite images indicate that a larger clear eye has formed, with the coldest cloud-top temperatures seen to date observed with the cyclone. While subjective Dvorak estimates have been fluctuating between 90-102 kt, the latest objective estimate is 102 kt, and a 1050 UTC AMSU estimate from CIMSS is 104 kt. A blend of these data gives an initial wind speed of 100 kt, making Lee the 5th major hurricane of the 2017 Atlantic season. A gradual decrease in water temperatures should start a weakening trend within 12-24 hours, with a faster weakening forecast on Thursday and Friday as Lee enters a high-shear environment. Guidance is in good agreement on this scenario, and the latest forecast is very close to the previous one. Lee has turned northwestward, or 315/6. The hurricane should turn to the north on Thursday and northeast by Friday while it moves around the subtropical ridge. Lee is expected to move quite quickly to the northeast on Friday and Saturday as it accelerates in mid-latitude flow. No significant changes were made to the previous track, and the new forecast lies between the ECMWF and the HFIP corrected-consensus model. Around day 3, the cyclone should be close to a cold front, but most of the models still show it separate from that feature. By day 4, all of the guidance have the system decaying into a trough, and that is the solution provided below. An ASCAT pass from this morning indicated that Lee has grown in size, so the initial and forecast wind radii have been modified to reflect that change. FORECAST POSITIONS AND MAX WINDS INIT 27/1500Z 30.6N 56.8W 100 KT 115 MPH 12H 28/0000Z 31.4N 57.3W 95 KT 110 MPH 24H 28/1200Z 33.0N 57.2W 90 KT 105 MPH 36H 29/0000Z 35.5N 55.5W 80 KT 90 MPH 48H 29/1200Z 39.0N 51.5W 70 KT 80 MPH 72H 30/1200Z 46.5N 34.5W 55 KT 65 MPH 96H 01/1200Z...DISSIPATED $$ Forecaster Blake
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