WTNT44 KNHC 150841

Remnants Of Isaac Discussion Number 31
NWS National Hurricane Center Miami FL AL092018
500 AM EDT Sat Sep 15 2018

A NOAA Hurricane Hunter aircraft investigated Isaac over the past few hours and was unable to identify a well-defined center. The plane found multiple small and poorly-defined circulations embedded within a larger area of weak and variable winds, well to the south of the previous estimated center location. The plane also found that the minimum pressure has risen to around 1006 mb. All of this data confirmed what two late-arriving ASCAT overpasses from earlier this evening indicated, that Isaac has opened up into a southwest to northeast oriented trough. Since Isaac does not have a well-defined center, it no longer meets the NHC definition of a tropical cyclone and this is the last advisory.

The strongest SFMR winds found by the plane were around 30 kt, mainly to the north of the deep convection, so the intensity has been set at that value. Although some of the regional hurricane models suggest that small short-lived circulations like the ones found by the plane could temporarily spin up within the larger envelope of the tropical wave over the next several days, none of the dynamical models currently show any significant redevelopment of Isaac. The wave will likely continue westward across the Caribbean Sea over the next few days, producing gusty winds and occasional heavy rains over portions of Hispaniola and Jamaica.

This is the last public advisory issued by the National Hurricane Center on Isaac. Additional information can be found in High Seas Forecasts issued by the National Weather Service, under AWIPS header NFDHSFAT1, WMO header FZNT01 KWBC, and available online at https://ocean.weather.gov/shtml/NFDHSFAT1.shtml.


INIT 15/0900Z 14.8N 70.8W 30 KT 35 MPH 12H 15/1800Z...DISSIPATED

$$ Forecaster Zelinsky