Hurricane Nate is doing three things:
- Getting more tropical moisture northward to get better rainfall coverage into the area this evening
- Tracking more toward Louisiana & Mississippi to Alabama, so we will get direct rainfall impact from the remnants tomorrow with a PRE- type situation in our southeastern areas of the Tri-State tonight with +2″ rainfall possible.
- With the PRE & the actual remnants of Nate, some areas in our southeastern counties of western Kentucky may see +5.5″ of total rainfall between tonight & tomorrow with much lesser amounts elsewhere.
There is not much in the way of really cold air aloft or deeper CAPE for good lightning discharge or more widespread severe weather threat, but wind fields aloft & shear/helicity values will increase over the next few hours over the area. Although the convection will be relatively shallow, there will still be some CAPE & the wind/shear parameters support the potential of an isolated brief tornado or two &/or severe gust over the area.
Two zones of convection will tend to develop with ropey squall line just ahead of surface cold front & clusters of multi-cells (perhaps a couple relatively low-topped supercells) farther ahead of the front. These will all tend to move to the northeast quite rapidly.
Even if there does not end up being watch issuance, be aware of the showers & some t’storms in the area this evening & the potential of isolated severe weather amidst already gusty south to southwest winds.
If there was more cold air aloft & more CAPE overall & deeper layering of CAPE through the troposphere, then a more substantial severe weather episode to event would occur given the wind fields/shear.
The showers & t’storms may then train over our southeastern counties into the night, even as areas farther north dry out. This will behave like a Predecessor Rainfall Event ahead of a land-falling hurricane. This may lead to locally-heavy rainfall of +2″ over southeastern counties in western Kentucky.
This, with the rainfall tomorrow may lead to +5.5″ rain amounts the southeast. This will result in localized flash flooding, even despite dry soils, given rate at which the rain may fall.