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Area forecast discussion
National Weather Service Jackson Kentucky
700 am EST sun Nov 17 2019

issued at 652 am EST sun Nov 17 2019

A quiet and cool morning across eastern Kentucky as the sun begins
it's rise. Forecast is in good shape given the lack of ongoing
weather. Did do some updates to the temperatures over the last
couple of hours to better capture the trends and current
observations. This also resulted in some small updates to the
morning lows. Expect temperatures to have reached their lowest
point during this 11z hour, and should begin improving heading
into 12z. All updates have been published and sent to ndfd/web.


Short term...(today through monday)
issued at 348 am EST sun Nov 17 2019

While high pressure will remain in control throughout the day, upper
level heights will begin to fall ahead of an approaching trough that
will move into the Mississippi Valley by late this afternoon.
Surface winds will remain light, but will change to a more S and
then SW direction during the afternoon ahead of this approaching
system. This will help boost temps a bit, with highs in the 50s
across the County Warning Area. Moisture will also begin advecting into the state,
resulting in increasing clouds from west to east late in the day.
These clouds will keep some insulation across the state throughout
the overnight, which along with deepening southerly flow, will allow
low temps to remain at or even just above freezing in most locations.

An upper level low will develop in the apex of the above-mentioned
trough, which is expected to traverse Kentucky throughout the day
Monday. This will couple with a surface cold front, which will make
its way into eastern Kentucky during the afternoon hours. This
surface front will be quite weak, however, with the latest wpc
analysis showing it dying across the County Warning Area. However, there is likely
enough forcing with the upper level low to result in some lift and
possible precipitation. Though not much, both the European model (ecmwf) and GFS are
showing some spotty isolated pops across the County Warning Area as the system moves
through during the afternoon. Confidence is low as to where and when
pops will occur across the cwa, however, it's also high enough to
want to include some pops. Even some of the cams are supporting some
spotty development. Otherwise, expect mostly cloudy skies to
continue, and winds to become more westerly throughout the day.
Highs will be a bit cooler compared to today considering the clouds
and cold air advection aloft during the afternoon, generally in the upper 40s to
around 50.

Long term...(monday night through saturday)
issued at 332 am EST sun Nov 17 2019

A vort Max will be exiting the area at the very start of the
period. However, model soundings support low level moisture
sticking around through Monday night, supporting some potential
for drizzle or light rain through the night. Still some
uncertainty on the depth of this moisture, but enough there to
support a slight chance of rain. The main shortwave axis will
pivot across and through the area on Tuesday, and while most
models lack moisture, the 00z European model (ecmwf) supports rain chances
lingering well into the day on Tuesday. Given this is the outlier
solution presently, will hold off on bringing rain chances into
Tuesday afternoon.

Heights will build quickly into Wednesday with temperatures
rebounding quickly for the middle of the week. We should see highs
back into the low 60s for Wednesday, and possibly into the mid 60s
by Thursday. A surface low will strengthen as it crosses into the
Great Lakes by late Thursday, with a trailing cold front crossing
east Kentucky. Models show a bit better agreement on the timing of
this front this morning, so have bumped pops up a bit more into
the high likely and categorical range. Still some question as to
how much cold air moves in behind the front as models suggest the
front stalling and shearing out with time over the area. Thus, the
cold air may not make it completely into the area. Thus,
confidence is low on the temperatures forecast from Friday Onward.
Models are starting to show some support for a developing southern
stream system over the weekend to impact the area with an extended
period of wet weather from Saturday into Sunday. As cold air wraps
into the area with the system exiting on Sunday, a few snowflakes
may be possible, but should not result in any impacts.


Aviation...(for the 12z tafs through 12z Monday morning)
issued at 701 am EST sun Nov 17 2019

Surface high pressure will continue to provide VFR conditions
across the area through the period. However, a system approaching
from the west will bring broken to overcast high clouds from west to east
throughout the afternoon and overnight. Winds will be light and
variable through the period at generally 5kt or less.


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