Area Forecast Discussion
Issued by NWS Louisville, KY
FXUS63 KLMK 221719
Area Forecast Discussion
National Weather Service Louisville KY
1219 PM EST Sun Jan 22 2017
...Updated Aviation Discussion...
Issued at 1020 AM EST Sun Jan 22 2017
Precip underperforming across the Tennessee Valley at the moment, so
have updated based on latest current trends along with HRRR and WRF
runs for today. Have not gone beyond 00Z for now, but may need to
lower evening POPs as well in later issuances.
.Short Term (Now through Monday)...
Issued at 256 AM EST Sun Jan 22 2017
An early morning analysis showed a compact stacked upper and surface
low over northern Texas with a warm front situated along the deep
south and Gulf Coast states. Locally, dry conditions prevailed with
mid/high clouds spilling north from convection across northern
MS/AL. Readings were mainly in the upper 40s to lower 50s.
For today, the stacked low pressure system over Texas will move
across MS/AL/GA where the bulk of showers and storms are expected to
be confined. Some showers will pinwheel north of the closed low back
into TN and central Kentucky but the latest guidance has really
backed off on the areal coverage and amounts with these bands, and
also delays precipitation moving in our area until at least the
As a result, trimmed back precipitation chances considerably this
morning, going dry along/north of the KY parkways and just 20-30
chances south to the TN. By afternoon, scattered showers will be
possible across the entire area but it appears the bulk of it will
be confined to south central KY and portions of the Bluegrass. Highs
will reach the low/mid 60s.
Better rain chances come tonight as the surface low deepens and
approaches the southern Appalachians. A deformation band of rain is
forecast to setup northwest of the low center, or across central TN
to central KY (along/east of I-65). North to northwest winds will
become gusty as the pressure gradient tightens with some gusts to 30
mph possible tonight into Monday morning. Plan on lows in the mid
40s to around 50 degrees.
On Monday, the storm system will move off the North Carolina coast
and any morning showers should begin to exit out of the area by
afternoon. The exception is the I-75 corridor and locations east
where showers may hang around into the evening hours. It`ll remain
mostly cloudy to overcast and noticeably cooler with highs around 50
Total rainfall for the event continues to decrease and will likely
stay under 3/4 of an inch for most places, the exception being the
Lake Cumberland region which might get around 1 inch.
.Long Term (Monday Night through Saturday)...
Issued at 259 AM EST Sun Jan 22 2017
The main weather highlight in the long term is a return to
normal to slightly below normal temperatures later in the work week.
After brief ridging and dry weather on Tuesday, a fast moving low
pressure system will track from the central Plains to the Upper
Midwest Wednesday. A cold front will sweep across the lower Ohio
Valley, and is expected to cross our region mainly dry as there is
lack of moisture convergence along the front. It`ll be very breezy
during the day with southwest winds sustained 15 to 25 mph with some
gusts 30 to 35 mph likely. Cold air advection kicks Wednesday night
through the remainder of the work week.
The big story will be the colder temperatures. Highs Thursday
through Saturday will range from the middle 30s to lower 40s, and
mornings low are forecast to be in the 20s. The latest blended data
set shows mainly dry conditions during this period, with just slight
chances of a rain/snow mix confined to the southern Indiana and
.Aviation...(18Z TAF Issuance)
Issued at 1219 PM EST Sun Jan 22 2017
Spiral band of showers will move northward across central KY this
afternoon impacting mainly KSDF and KLEX between 22/18-21Z producing
light rain and MVFR/VFR ceilings. Ceilings look to settle into the
MVFR range this evening with mainly scattered sprinkles and drizzle.
Short term high resolution models do not show much activity across
the region this evening...most likely due to large convective
complex moving across the southern US. The high res WRF runs do
show another E-W band of showers possibly affecting KSDF and KLEX
between 23/00-03Z with a more widespread band of showers affecting
KSDF and most likely KLEX later on tonight as a strong area of low
pressure passes southeast of the region. Ceilings look to lower to
near IFR levels late tonight and surface winds will increase due to
the increasing pressure gradient across the region. Winds this
afternoon will start of out of the SE at KBWG and KLEX and then
shift to the northeast and northwest overnight. Winds are expected
to become gusty late tonight with sustained winds of 10-15KT with
gusts up to 25KT at times...most likely toward 23/12Z.