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Tropical Storm Jerry Forecast Discussion Number 18
2019-09-21 22:51:02| National Hurricane Center (Atlantic)
Issued at 500 PM AST Sat Sep 21 2019 000 WTNT45 KNHC 212050 TCDAT5 Tropical Storm Jerry Discussion Number 18 NWS National Hurricane Center Miami FL AL102019 500 PM AST Sat Sep 21 2019 Jerry has become quite disorganized this afternoon. The low-level center is exposed to the northwest of a small area of persistent deep convection. The NOAA G-IV aircraft, which is flying a research mission in and around the tropical storm, measured a minimum pressure of 1004 mb with 17 kt of wind, implying that the minimum pressure of Jerry has increased since this morning. However, ASCAT data from a couple hours after an Air Force Reserve hurricane hunter plane completed its mission into Jerry showed that the maximum winds were still 50-55 kt. The max winds are therefore conservatively held at 55 kt for this advisory. Only minor adjustments were made to the NHC intensity forecast, and users should not focus on the 5 kt difference between a tropical storm and hurricane, especially at 72 h and beyond. Based on Jerry's disheveled appearance, significant strengthening does not seem imminent. That said, the HWRF and HMON forecast that the cyclone will quickly restrengthen tonight or tomorrow and become a hurricane again. If the shear decreases during the next 24 hours, that is possible, however SHIPS diagnostics suggest that will not happen. The NHC forecast instead follows the statistical guidance, and keeps Jerry in a more-or-less steady state through day 5. The cyclone is still forecast to be near hurricane strength when it moves near Bermuda next week, and there is still a distinct possibility that Jerry will re-gain hurricane strength at some point during the next 5 days. All of the models still show Jerry turning northward later today or on Sunday toward a break in the subtropical ridge, and then turning northeastward ahead of an approaching mid-latitude trough. This track will bring Jerry close to Bermuda by late Tuesday or early Wednesday. The model spread has increased a little since the last advisory, but confidence in this scenario is still high. The NHC track forecast has been adjusted only slightly to the west and remains near the multi-model consensus through day 5. Key Messages: 1. Jerry is forecast to be near hurricane strength when it moves near Bermuda late Tuesday or early Wednesday. It is too soon to determine what impacts the system may have on the island but interests there should monitor the progress of Jerry. FORECAST POSITIONS AND MAX WINDS INIT 21/2100Z 23.0N 65.8W 55 KT 65 MPH 12H 22/0600Z 24.3N 66.9W 55 KT 65 MPH 24H 22/1800Z 25.8N 67.6W 60 KT 70 MPH 36H 23/0600Z 27.0N 67.8W 60 KT 70 MPH 48H 23/1800Z 28.5N 67.8W 60 KT 70 MPH 72H 24/1800Z 31.5N 66.5W 60 KT 70 MPH 96H 25/1800Z 35.5N 61.5W 60 KT 70 MPH 120H 26/1800Z 40.0N 56.0W 60 KT 70 MPH $$ Forecaster Zelinsky
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