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Area forecast discussion 
National Weather Service Jackson Kentucky
112 PM EDT Monday may 4 2015

issued at 110 PM EDT Monday may 4 2015

Forecast was still in good shape. Blended middle day observation into the

Update issued at 927 am EDT Monday may 4 2015

Have reduced sky cover a bit for today. It is a clear start...and
forecast soundings look fairly dry. Other changes made were of
little significance.

Update issued at 701 am EDT Monday may 4 2015

Forecast seems to be in good shape so far this morning under a
high pressure regime. Biggest concern over the next few hours will
be the temperature Ridge Valley splits subside and
temperatures quickly climb to 70 by noon. Went ahead and removed
mention of fog in the grids as well as the zone what
is left out there should be burning off over the next hour or so.
Daytime mixing should lead to a slight uptick in winds /though
still light/ and the potential for some isolated daytime
cumulus...with otherwise very quiet conditions. That being
other major updates are needed at this time.


Short term...(today through tuesday)
issued at 301 am EDT Monday may 4 2015

Strong high pressure/ridging will stay in control through the extent
of the short term. Plan view model output is finally trying to steer
away from any afternoon convective would make sense
given the strong lack of moisture across the region. Latest forecast
soundings are still pointing at just enough moisture to allow for
some isl/scattered afternoon cumulus development over the next couple of days...
with the addition of some slight mixing down of winds /still
generally 10 kts or less/. Did note...however...that over the
highest terrain...the latest nam12 run has actually moistened up a
bit for Tuesday afternoon...though think this may still be a bit
overdone...and near surface dry layer should eliminate any precipitation
threat. Otherwise... light srly flow and good sun coverage will
continue to boost temperatures. Expect generally low 80s both
today and tomorrow for highs...while optimal radiational cooling
overnight will continue to promote large Ridge Valley splits in
temperature. This could mean some sizable diurnal temperature
ranges for valleys between morning lows and daytime highs.

Long term...(tuesday night through sunday)
issued at 400 am EDT Monday may 4 2015

The models remain in good agreement that an upper level ridge
will generally remain in control across the southeastern Continental U.S.
Through the first part of the weekend...before shifting east and
weakening a bit for the latter half of the weekend. There are a
few differences between the GFS and European model (ecmwf) from Wednesday through
Friday regarding a weak upper level tropical low that attempts to
move in from the Carolina coast. The GFS is the most aggressive in
bringing this feature inland...which would allow for a bit more of
a weakness in the ridge...perhaps enough to allow for some
isolated convection across our southeastern terrain counties. The
European model (ecmwf) keeps the low offshore...which would likely keep a lid on
convection besides perhaps a stray shower or storm. For now...will
maintain continuity from the previous forecast and keep the rain
mention out until Sunday. Temperatures will average well above
normal through the period...with highs in the low to middle 80s. The
lows will slowly moderate through the period...starting out in the
upper 40s in the cooler sheltered valleys Wednesday morning...and
then low to middle 50s by the end of the week.


Aviation...(for the 12z tafs through 12z Tuesday morning)
issued at 702 am EDT Monday may 4 2015

Expect VFR conditions through the period. Included mention of
some daytime cumulus development and slight mixing down of winds...but
taf sites should still remain generally below 10 kts. Clouds will
lift and winds will die down once more by this evening. While
areas of valley fog are possible by late not expect
taf sites to be affected.


Jkl watches/warnings/advisories...


short term...jmw
long term...geogerian

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