Area Forecast Discussion
Issued by NWS Jackson, KY
FXUS63 KJKL 230802
AREA FORECAST DISCUSSION
National Weather Service Jackson KY
302 AM EST Mon Jan 23 2017
.SHORT TERM...(Today through Tuesday)
Issued at 301 AM EST MON JAN 23 2017
The general model consensus is calling for an unusually deep area
of low pressure to continue moving eastward across the Tennessee
valley tonight, and eventually across the Carolinas and then
offshore Monday night into early Tuesday morning. As the low
rotates across the TN valley tonight and during the day Monday,
we can expect to see numerous light to moderate rain showers
moving across the area. The rain will taper off very slowly today
and tonight, and should be exiting eastern Kentucky by late
Tuesday morning. Rainfall amounts across far southeastern Kentucky
could still lead to significant rises on creeks and streams, and
perhaps isolated instances of minor flooding through late Monday
Temperatures will be significantly cooler than what we saw over
the weekend, but will still be above normal for the time of year
today and tomorrow. Highs today and Tuesday are expected to max
out in the lower 50s both days. Tonights lows should only fall to
around 40, with ongoing precipitation and extensive cloud cover
acting to moderate things a bit in that regard.
.LONG TERM...(Tuesday through Sunday)
Issued at 329 PM EST SUN JAN 22 2017
The period will feature the completion of a large scale pattern
change, putting an end to our long stretch of above normal
temperatures, and marking the beginning of a run of below normal
The intense storm system currently in the deep south will have
progressed to the Mid Atlantic coast by Tuesday morning, and its
last influence in the form of cloudiness and perhaps a few showers
will be pulling out of the JKL forecast area during the day.
Ridging at all levels will pass over Tuesday night, with warm air
advection beginning before dawn. This will likely lead to
ridge/valley differences for lows. An intense low pressure system
heading northeast toward the Great Lakes will bring a tightening
pressure gradient locally, which could bring rising temperatures
by dawn on Wednesday, even in many valleys. One more mild day will
occur on Wednesday, ahead of the system`s cold front. That cold
front will arrive late Wednesday or Wednesday evening. Only modest
moisture return is expected before the front arrives, and little
or no precipitation is expected with fropa.
Our regime after fropa will feature persistent low level west to
northwest cyclonic upslope flow and cold air advection- a recipe
for clouds and when it`s cold enough, flurries and snow showers.
There will be multiple impulses moving through the flow aloft.
Trying to time these at long range is problematic. Have used an
extended period of very light precip potential, with some minor
peaks when a model blend shows the best agreement for embedded
upper level waves passing through the large scale trough. One
peak is on Thursday, and another on Sunday. On Thursday, temps
will still could be warm enough for rain or rain mixed with snow.
However, any precip in the remainder of the period should be snow.
.AVIATION...(For the 06Z TAFS through 06Z Monday night)
ISSUED AT 1243 AM EST MON JAN 23 2017
The airports across eastern Kentucky will experience widespread
light to moderate rain showers through 22 or 23Z today, before the
rain finally being to taper off. MVFR to LIFR conditions will be
possible through the end of the TAF period at all TAF sites. The
worse conditions are expected to occur between 11 and 18Z today,
with low CIGS being the primary issue. Northeast winds will back
to northwesterly through the night and into Monday with speeds
increasing to 10-12 knots, while also becoming gusty at times.