Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Louisville Kentucky
300 PM EDT Thursday Sep 3 2015
Short term (now through Friday night)...
issued at 250 PM EDT Thursday Sep 3 2015
Stagnant late Summer pattern continues across the Ohio Valley, with
just enough of a breakdown in the ridging that we have seen a couple
of renegade cells over the Bluegrass region. Isolated thunderstorms
could pop just about anywhere through sunset, probably with a bit
more coverage than the last two days but still less than 20%.
Look for patchy fog to develop in the river valleys again overnight,
with persistent hazy conditions for much of Friday morning across a
broader area. Lows will still come in just either side of 70 for
tonight and Friday night, with highs just either side of 90 on
Friday afternoon. If anything, Friday T-storm coverage may be a bit
more focused in the east given subtle height rises, but still 20% or
Long term (saturday through thursday)...
issued at 254 PM EDT Thursday Sep 3 2015
Warmer than normal conditions will continue through the weekend and
into early next week as a persistent ridge remains in place across
the eastern Continental U.S.. high temperatures will top out in the upper 80s
to lower 90s each day. Some storms will be possible, mainly in the
afternoon across southeast central Kentucky. In this region there
will be a bit better moisture available. However, do not think
coverage will be more than isolated.
The ridge will begin to break down by middle week as a trough pushes
into the northern Continental U.S.. a front will approach and move through the
region by the end of the forecast period. The 12z European model (ecmwf) has slowed
the movement of this front through the area, closer to what the GFS
has been advertising. Thus Wednesday into Wednesday night looks to
be the most likely time frame for the front to move through. There
will be a better chance for storms across the region as this front
moves through, so will carry higher probability of precipitation towards the end of the
forecast period. Temperatures will also cool off by the second half
of the week with highs potentially in the lower to middle 80s.
Aviation (18z taf update)...
issued at 1230 PM EDT Thursday Sep 3 2015
Stagnant pattern continues, giving US a largely persistence
forecast. Main challenge will be the impact of morning haze/fog,
which will provide several hours of MVFR visibility. As with the
past two days, will keep the restriction in until late morning at
sdf, while bwg/Lex should go VFR by mid-morning.
Otherwise look for light northwest winds and scattered diurnal cumulus.
Afternoon pop-up storms will be too isolated to be worthy of
inclusion in the tafs.