Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

fxus63 kjkl 162047 

Area forecast discussion
National Weather Service Jackson Kentucky
447 PM EDT Mon Sep 16 2019

Short term...(this evening through Tuesday night)
issued at 447 PM EDT Monday Sep 16 2019

The latest surface map features a weak cold front draped across
the Ohio Valley, with high pressure centered near the Great Lakes,
as well as near the middle Mississippi Valley. Aloft, a Stout Ridge
axis is aligned along the Mississippi Valley, with troughing out
west, as well as in the east. The weak surface cold front, as well
as a subtle short wave trough nudging southeastward on the front
side of the ridge, have allowed for a few showers to pop up
across portions of eastern Kentucky. No thunder has been noted as
of yet across our area; however, there have been a few pulses
noted just upstream, closer to the better instability.

A stray shower or storm will continue to threaten eastern Kentucky
through early this evening, as the surface front pushes closer to
the area. The threat will diminish as we lose heating tonight.
The cool air advection behind this boundary looks weak later
tonight. Models are playing up low clouds and or fog behind the
boundary; however, given our ongoing dry conditions in place, feel
these might a bit overdone. Consequently, lows will be a little
trickier, as guidance suggests milder readings. Have undercut the
numbers somewhat, generally low to mid 60s.

Clouds will mix out during the day on Tuesday, with highs at least
a few degrees cooler than today, generally upper 80s to around 90.
Tuesday night will feature mostly clear skies, patchy valley fog,
and lows in the low to mid 60s, with a few upper 50s possible in
the northeastern valleys.

Long term...(wednesday through monday)
issued at 447 PM EDT Monday Sep 16 2019

Upper level ridging and dry weather will be the main story
through the weekend, as capping should be enough to prevent
convection each day. Stuck fairly close to the blended guidance
for the highs/lows, besides the normal terrain adjustments, which
allowed for slightly cooler valley temperatures in the east. Highs
will average in the mid to upper 80s, still around 10 degrees
above normal for this time of year.

By early next week, the models differ on bringing a more robust
short wave trough and surface front across the Ohio Valley. The
GFS is much more robust with these features, while the European model (ecmwf)
weakens these significantly as they approach eastern Kentucky.
Given the ongoing dryness in place, will side closer to the European model (ecmwf).
As such, have only allowed for slight chance pops by next Monday.


Aviation...(for the 18z tafs through 18z Tuesday afternoon)
issued at 229 PM EDT Monday Sep 16 2019

An approaching weak cold front will allow for the potential of some
isolated convection across the area through early this evening.
Given the limited areal coverage, will continue to leave out this
mention at any taf sites. Model guidance suggests some fog/low
clouds building in between 06 and 12z. For now, included some MVFR
fog at ksym, ksme, and kloz generally between 09 and 13z. Given
the ongoing dry conditions, do not feel confident going with any
worse conditions for now. Any fog will burn off by 13z, with some
diurnally driven cumulus popping up once again by early Tuesday
afternoon. Winds will average around 5 kts or less, generally
veering to the north to northeast through the period.


Jkl watches/warnings/advisories...

National Weather Service Glossary of Abbreviations