Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Jackson Kentucky
400 am EDT Monday may 4 2015
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 development...as 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 decoupling of winds. 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 06z tafs through 06z Monday night)
issued at 139 am EDT Monday may 4 2015
Expect VFR conditions through the period. Included mention of
some daytime cumulus development and slight decoupling of winds...but
taf sites should still remain generally below 10 kts. Clouds will
lift and winds will die out once more by tomorrow evening.