558
FXUS63 KLMK 031123
AFDLMK

Area Forecast Discussion
National Weather Service Louisville KY
623 AM EST Tue Nov 3 2026

.KEY MESSAGES...

* Widespread rainfall tonight into Wednesday will benefit the
  ongoing drought. Amounts of 1 to 1.75 inches will be most common,
  though a few locations (10% chance) may see totals surpass 2.5
  inches. The risk of flooding is low.

* The risk for severe weather is low, though brief and localized
  gusty winds exceeding 40 mph may (20-30% chance) accompany
  showers tonight into tomorrow.

&&

.DISCUSSION...
Issued at 328 AM EST Tue Nov 3 2026

*** Warm and pleasant today ***

Early Tuesday morning, the area is situated between high pressure
over the Mid-atlantic and a large, upper-level low pressure system
across the Great Plains. Between these two features, a tight surface
pressure gradient will favor 10-20 mph winds out of the south-
southeast, with a few gusts approaching 30 mph at times late morning
through the afternoon mainly near and west of the I-65 corridor.
Coupled with morning sunshine, this will warm temperatures into the
mid to upper 70s area-wide this afternoon, with a few spots
potentially topping 80. The National Blend of Models (NBM) gives the
highest chances (30-50%) for 80+ degree highs today south of a
roughly Tell City to Berea line. Meanwhile, clouds will increase
from west to east during the afternoon as an increasingly moist
airmass overspreads the region ahead of the aforementioned Great
Plains low.

*** Breezy with beneficial rain tonight into tomorrow ***

A 55-65 kt 850mb LLJ will overspread the local area tonight,
strengthening moisture advection and sparking scattered showers
after around 10pm EDT. With HREF mean bringing PWAT values into the
1.6-1.75 inch range (95-99th percentile of climatology), a
seasonably deep (10-12 kft) warm cloud layer, and cloud-bearing
layer winds nearly parallel to the eastward-moving front, the set up
will be favorable for some training heavy showers and, hence, swaths
of hefty rainfall totals late tonight into tomorrow morning. LPMM
places these highest amounts (2-3+ inches) roughly along the I-65
corridor, which is where NBM`s probability for more than 2 inches of
rainfall is also maximized at 20-40% (highest south of E-town). This
should be a beneficial rain for most if not all of the area given
ongoing drought conditions, but we can`t completely rule out an
instance or two of nuisance flooding given (1) most of this rain
will fall in a 4-6 hour period, (2) River Forecast Center (RFC) 6-
hour Flash Flood Guidance (FFG) is around 3 inches, and (3) the
antecedent dry conditions may have led to some crusting over of the
ground which would increase initial runoff; in addition, urban areas
may be more prone to problems if any storm drains are clogged with
leaf debris.

While kinematics appear impressive overnight tonight into tomorrow
morning, with the GFS depicting 45-60 kt (highest west) of 0-6km
bulk shear, two things will be working to limit the potential for
severe weather: (1) instability will be limited with the
HRRR/NAMNest only depicting 200-500 J/kg (elevated) MUCAPE, and (2)
forcing will be weakening along the cold front as the low occludes
over the Upper Midwest. Still, just enough of this instability may
poke into the hail growth zone (HGZ) to spark a lightning strike or
two in the stronger cells; but even without robust convective
updrafts or lightning, the intense environmental synoptic-scale flow
could be transferred to the surface to produce localized strong wind
gusts exceeding 40 mph. Since this should be both isolated in nature
and tied to showers, a Wind Advisory will not be needed, though a
few convective Special Weather Statements (SPSs) may be.

With the cool front`s eastward progression slowing down, the rain
and locally/sporadically gusty winds will linger into the afternoon
tomorrow, perhaps not winding down until after sunset across parts
of the Bluegrass. Conditions will turn slightly cooler behind the
front, though low level moisture will linger amidst continued
cyclonic flow and we may see some drizzle tomorrow evening into
tomorrow night.

*** Turning seasonably cool this weekend ***

The next system will have considerably less moisture to work with,
and will only bring the area 10-20% chances (highest north) for
measurable rainfall during the day on Friday. However, temperatures
are currently forecast to turn a bit cooler in its wake. Though
confidence remains low on how much we cool down and how long it
lasts with the northern stream jet largely remaining north over the
Great Lakes, at the very least we can expect some chilly overnight
lows given the drier airmass. NBM probabilities for cooler than 36
degree overnight lows are running at 50-70% across the area (except
lower chances in urban cores) both Sunday and Monday nights,
suggesting we may see frost.

&&

.AVIATION /12Z TAFS THROUGH 18Z WEDNESDAY/...
Issued at 623 AM EST Tue Nov 3 2026

Southerly surface winds will increase sharply - to 10-15 kt with
gusts to around 20 kt - after around 15z, reducing ongoing marginal
LLWS significantly. After around 04z, a stronger low level jet will
develop, resulting in another round of LLWS, numerous showers
(possibly with a rumble of thunder as well), and lowering ceilings.
Confidence was not high enough in thunder at any point during the
forecast period to add a prob30, but it could (10-20% chance) occur
anytime after around 04z.

&&

.LMK WATCHES/WARNINGS/ADVISORIES...
KY...None.
IN...None.

&&

$$

DISCUSSION...JRB
AVIATION...JRB