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Area forecast discussion 
National Weather Service Jackson Kentucky
754 am EDT Wednesday Apr 16 2014

issued at 754 am EDT Wednesday Apr 16 2014

Made only minor changes to update for observed conditions blending
into the daytime forecast.


Short term...(today through thursday)
issued at 340 am EDT Wednesday Apr 16 2014

Cold temperatures and dry air are the concerns during the period. A
ridge of surface high pressure overhead this morning will be situated
just to our east by late Thursday...providing mainly clear skies.

Temperatures are presently below freezing area-wide. Even with
sunshine...temperatures aloft will only support recovery into the 50s
today...perhaps just touching 60 in the warmest locations. Since
there is still a lack of significant greenery and resultant
evapotranspiration...we should see exceptionally low dew points for
middle April as drier air aloft mixes down during the day. This should
lead to afternoon relative humidity below 25 percent. Fortunately for
fire weather concerns...winds will not be much of an issue.

Weak warm air advection should occur tonight and Thursday. This will
help to keep ridges and open terrain milder tonight. However...clear
skies...light winds...and dry air should allow valleys to decouple
and see temperatures fall well below freezing again. With temperatures off
the surface significantly warmer on Thursday...surface readings
should show a strong rebound during the day...with highs close to
normal. The air will still be dry with relative humidity dropping below 25 percent
again for most of the area...but winds will still be light.

Long term...(thursday night through tuesday)
issued at 340 am EDT Wednesday Apr 16 2014

Decent agreement amongst the models this morning. The period will
start with a middle level trough pushing east across the Central
Plains. It looks like this feature will keep one vorticity maximum to our
north with another one to our south as it crosses the area on
Friday. This will keep the forcing weak over Kentucky and provide
little support for showers as it crosses the area. In fact the two
waves appear to be diverging away from the area. However...given the
presence of a weak surface trough...could not rule out an isolated
shower popping up during the afternoon or evening as it crosses into
eastern Kentucky. High pressure will then build down from the Great
Lakes for the upcoming weekend...providing a dry and pleasant
weekend. The next chance of rain will then hold off until late
Sunday night or Monday as another middle level trough pushes east
across the Ohio River valley. This looks to be our next best chance
for widespread rainfall. Rain chances will continue through Monday
night and into Tuesday morning before the trough departs to our
east. Dry weather...thanks to another area of high pressure will
then return for the middle of next week.

Dew points may hold quite a bit lower than models suggest into the
weekend...setting the stage for several more nights of lows into the
30s in the valleys and the possibility of more frost.
However...temperatures should stay above freezing from Thursday
night Onward. Large diurnal temperature swings can be expected
through the weekend with a somewhat dry air mass overhead this
weekend. We will stay mild into next week with highs around 70 and
milder overnight lows with clouds and precipitation keeping lows
closer to 50.


Aviation...(for the 12z tafs through 12z Thursday morning)
issued at 754 am EDT Wednesday Apr 16 2014

VFR and light winds are expected through the period.


Jkl watches/warnings/advisories...
freeze warning until 10 am EDT this morning for kyz044-050>052-

Freeze warning from midnight tonight to 9 am EDT Thursday for

Frost advisory from 3 am to 9 am EDT Thursday for kyz044-050-051.



short term...hal
long term...kas