061 
FXUS63 KLMK 131132
AFDLMK

Area Forecast Discussion
National Weather Service Louisville KY
632 AM EST Thu Feb 13 2025

...Updated Aviation Discussion... 

.KEY MESSAGES...

*  Widespread rainfall between 2 and 5 inches Friday night through 
   early Sunday will likely lead to widespread areal, river, and 
   isolated flash flooding. Falling temperatures on Sunday could 
   cause light snow to mix in on Sunday.

*  Rapidly falling temperatures into the teens could cause lingering 
   wet surfaces to freeze. Black ice may be possible for the Monday 
   morning commute.

*  Another system could bring additional snow showers on Tuesday and 
   Wednesday of next week.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 307 AM EST Thu Feb 13 2025

Cold air will continue to advect in behind the departing cold front 
today as strong sfc high pressure continues to build over the 
central CONUS. Pressure gradient will tighten over the region 
producing breezy 20-25 mph gusts out of the west-northwest. Low 
level moisture will remain under a temperature inversion keeping 
skies cloudy to mostly cloud for most of the day. This will keep it 
relatively chilly through out the day with temperatures in the 
low/mid 30s during the afternoon. As drier air continues to work in 
from the west, skies should start to clear later in the day and we 
might get a brief period of sunshine in the late afternoon to right 
before sunset. 

High pressure will continue to build over the region overnight, 
clearing skies and diminishing winds. This will result in a cold 
overnight with lows in the mid/upper teens with right around 20 
across out southern tier of counties close to the KY/TN border. 

For those with concerns regarding the flooding expected this 
weekend, today and tomorrow will be the last days to bring 
preparations to completion. (See below)

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
Issued at 307 AM EST Thu Feb 13 2025

Friday...

We'll enjoy a dry day on Friday as surface high pressure centers to 
our NE. We should see a good amount of sunshine at least through the 
morning and early afternoon. By mid to late afternoon, we'll see 
increasing mid and upper sky cover ahead of the next system. Surface 
winds don't really veer to a southerly component through the 
daylight hours, so likely won't be able to tap into any warm 
advective component. We will get a nice diurnal spike from morning 
lows in the teens and low 20s, but still only expecting upper 30s 
and 40s across the area.

Friday Night - Sunday Night...

A strong storm system is expected for the weekend, and will bring 
flooding impacts to our region. A Flood Watch has been issued for 
early Saturday morning through early Sunday afternoon. Widespread 
areal and river flooding along with isolated flash flooding are all 
possible. 

A trough will steadily move out of the western CONUS, and into the 
central CONUS through the weekend. Meanwhile, surface low pressure 
is expected to develop and strengthen from around the Red River 
Valley up through the central Appalachians, with a surface low track 
near or directly over our CWA. We'll see overrunning precipitation 
with isentropic lift beginning late Friday night/early Saturday 
morning, before stronger low level jetting and favorable mid and 
upper level forcing take hold through Saturday as the trough axis 
arrives. The combination of the strong low level moisture transport 
and good mid to upper level support will yield widespread rainfall, 
along with a more concentrated frontogenetical band of precipitation 
embedded within. The biggest issue is that this band could stay 
nearly stationary, or waffle slightly before finally being pulled 
through as the surface low/cold front passes Saturday night. In the 
meantime, precipitation totals are likely to add up where this band 
sets up and lingers. Models have been consistent in saying that this 
will most likely be across our southern and central CWA, and some of 
the data from earlier today have backed off from a more northern 
solution. We tend to like the southern solution in this type of 
setup as the frontal band can self-reinforce and limit northward 
progression sometimes. See this more often in pure convective 
situations with reinforcing outflow, but could happen in this 
scenario too, as suggested by the 12/12z global C-Shield solution. 
Bottom line is that there is very high confidence in flooding 
potential across central and southern KY, with less confidence in 
the extent of precipitation across southern IN and far north central 
KY. 

Overall, the QPF forecast hasn't changes much with 2 to 5 inches 
expected across the Watch area. Heaviest rain still looks to fall in 
the Green and Cumberland basins, along with the Rolling Fork and 
Rough River basins. The Kentucky River basin will see a lot of 
upstream contributions from the eastern KY heavy rain, plus 2 to 3 
inches over the basin itself in our area. Much of that water 
eventually finds its way into the Ohio where flooding will also be 
likely later into next week. 

Also want to mention we could see a brief severe threat if the 
surface low is able to pull up any instability across our SE CWA on 
Saturday evening/night. Right now, it appears we are lacking 
instability, but perhaps a brief window could materialize if the 
track is far enough NW. Something to watch, but seems a fairly low 
probability at the moment.

Cold front passes through late Saturday night, with precipitation 
ending west to east on Sunday. Could see a brief change over to snow 
on the back side, but not expecting any issues from that at this 
time. It is worth noting that temperatures drop well into the teens 
by Sunday night, so any lingering puddles, wet roadways, etc will 
have a good chance to freeze. Black ice due to lingering wet 
roadways could be a secondary concern.

Monday - Wednesday...

Fairly high confidence in a dry Monday as high pressure briefly 
builds in. However, lower confidence for Tuesday and Wednesday as a 
weak wave or two may slide through the area. Looks like a pretty 
cold stretch with highs mostly in the 30s each day and lows in the 
teens and low 20s. Any precipitation by mid week has a chance to be 
snow, and some light accumulations could be possible.

&&

.AVIATION /12Z TAFS THROUGH 18Z FRIDAY/...
Issued at 632 AM EST Thu Feb 13 2025

Flight categories will range from IFR for LEX/RGA to MVFR for 
SDF/HNB/BWG through most of the day as drier, cooler air filters 
into the region. Low level moisture will remain trapped under an 
inversion keeping the low stratus around for bulk of the day. High 
pressure builds in from the west tightening the pressure gradient 
over the region. Winds will gust to 20-25kts  this afternoon. As the 
high pressure gets closer the skies will start to clear and we will 
start to see VFR flight categories return as winds diminish later 
tonight.

&&

.HYDROLOGY...
Issued at 632 AM EST Thu Feb 13 2025

Another strong storm system will arrive this weekend, with an 
additional 2 to 5 inches of rain in the forecast. Central and 
southern KY are currently expected to see the higher totals out of 
this wave as well. Overall, total rainfall amounts through next 
Sunday could range between 2 and 3 inches across southern Indiana 
and north central KY, and 3-5 inches in southern Kentucky. 

With already saturated soils, and area rivers and streams continuing 
to run high, these waves of rain will make areal flood and river 
flood threats increase as we move through the week. The river basins 
that stand the biggest threat of widespread minor flooding, and 
higher impacts, would be the Green, Rough, Rolling Fork, Cumberland, 
Kentucky, and Licking. The Ohio River will also see notable rises 
with added rainfall and contributions from tributaries. All of these 
streams will be subject to minor flooding, and there's about a 30-
50% chance of some spots reaching moderate flooding on the Kentucky 
River. Lower, but notable, chances for major flood in some locations 
are also on the table. A moderate risk (level 3 out of 4) of 
excessive rainfall has been outlooked for much of central and 
southern KY by the Weather Prediction Center.

Stay up to date of the latest forecasts during this active and 
impactful stretch of weather.

&&

.LMK WATCHES/WARNINGS/ADVISORIES...
KY...Flood Watch from late Friday night through Sunday afternoon 
     for KYZ023>031-033>043-045>049-053>057-061>067-070>078-
     081-082.
IN...Flood Watch from late Friday night through Sunday afternoon 
     for INZ084-089>092.

&&

$$

SHORT TERM...BTN
LONG TERM...BJS
AVIATION...BTN
HYDROLOGY...BJS