Area Forecast Discussion
Issued by NWS Paducah, KY
FXUS63 KPAH 290829
Area Forecast Discussion
National Weather Service Paducah KY
329 AM CDT THU SEP 29 2016
.SHORT TERM...(Today through Saturday)
Issued at 315 AM CDT Thu Sep 29 2016
It still appears that the closed upper low sinking south through
central IN will be the main influence over the short term. It
should finally stall out somewhere over central KY later tonight,
then loop counterclockwise back nw into southern IN on Friday.
While scattered showers will be possible again today over our n/e
counties, esp in portions of sw IN, the highest pops will come on
Friday as the low retrogrades back toward the forecast area.
They should primarily impact southwest Indiana and the Pennyrile,
but areas all the way back to the Mississippi River may not be out
of reach. Considerable day time clouds and n/nw winds will help
hold afternoon temperatures in the 60s to near 70 at many
locations east of the MS RIver today and Friday.
00Z deterministic GFS still indicates CAPES of 500-1000 J/KG
over about the eastern half of the region Friday afternoon, so
will include chc of thunder too, esp in sw IN. Given the cold pool
aloft and relatively cool sfc temps, any storms that manage to
form could contain some small hail. Cold air funnel clouds cannot
be completely ruled out either, though those features rarely touch
down or cause much in the way of damage impacts.
Pops will gradually decrease later Friday night and Saturday as
the upper low finally begins to lift off to the northeast. With a
bit more sunshine expected Saturday afternoon, should see temps
climb back into the 70s over much of the region.
.LONG TERM...(Saturday night through Wednesday)
Issued at 325 AM CDT Thu Sep 29 2016
A mid/upper low will be on its way out of the northeastern fringes
of the PAH forecast area by Saturday night. The medium range models
indicated that any measurable pcpn will have ended for us by then,
but a decent amount of fair-weather cumulus should still be around
through sunset on Sunday as the low moves through the Great Lakes.
Weak flow aloft will continue through the early part of next week,
transitioning from cyclonic to anti-cyclonic as ridging builds
between a tropical system along the Atlantic seaboard and a
progressive but weakening trof centered in the northern Rockies/
Plains. The ECMWF has been a bit more inconsistent and faster with
the western system, which should affect our region by mid week. A
more GFS-like (slower) solution is favored, supported by the EC/GFS
ensemble means. This means a slight downplaying of pcpn from the
already downward-trending initialization blend, especially
Wednesday, as a surface cold front approaches. Some scattered
showers and perhaps tstms could be in southern IL/southeastern MO by
Day 7 night (Wed).
A gradual warming trend is expected through the extended period,
ending in above average temps. The somewhat cooler GFS MOS was given
a bit more weight in the numbers.
Issued at 1154 PM CDT Wed Sep 28 2016
With the loss of daytime heating, clearing occurred faster than
expected at each of the WFO PAH TAF sites. The onset of scattered
to broken ceilings will increase overnight as the upper low moves
closest to the region between 10z-14z. Adjusted ceilings upward
slightly from previous forecast issuance.