Area Forecast Discussion
Issued by NWS Paducah, KY
FXUS63 KPAH 261956
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PADUCAH KY
256 PM CDT Sat Jul 26 2014
.SHORT TERM...(Tonight through Monday night)
Issued at 255 PM CDT SAT JUL 26 2014
All evidence points to the cap (see ILX and DVN 18Z RAOBS)
holding strong across the area late this afternoon and tonight.
The lone exception may be along the I-64 corridor, where a
complex of thunderstorms may push rapidly eastward generally in
the 01Z-05Z timeframe this evening.
The HRRR is still unable to generate a larger-scale bowing system,
as seen on some of the shorter range models this morning. The 12Z NAM
and GFS soundings show some weakness at times in the mid-level
flow across our north, so the overall organization of any storms
that develop may not be as significant as previously thought.
Individual storm cells may have enough 0-3KM SRH to support
rotating updrafts and would not be surprised to see some
supercells initially, where storms can develop this evening.
Damaging winds and large hail will be possible, and a few
tornadoes can not be ruled out with any individual cells this
evening. However, figure the cap will suppress any activity that
tries to dip south of I-64, or possibly even into our northern-
The mid-upper 70 dewpoints have descended upon the region as expected,
and heat indices have reached triple digits over much of the area.
Already issued a Special Weather Statement for the heat. It should
subside by 7 PM, and would be surprised to see values above 105,
so will not be issuing a Heat Advisory at this time.
Overnight, the models struggle to generate much, if any,
convection over our region, so will keep PoPs at 30% or less.
The cold front will move through the region Sunday, and the low
to mid 70 dewpoints and temperatures well into the 90s are
expected ahead of it over the southeast 2/3 of the area in the
afternoon. This could lead to heat indices near today`s levels,
and a righteous airmass for strong to severe thunderstorms to feed
on. Winds ahead of the front will be nearly due west, and quite
strong, pushing Lake Wind Advisory levels, especially east of the
Mississippi River. The veered winds result in only weak
convergence along the boundary, so thunderstorm coverage is
expected to be widely scattered to scattered, with better coverage
later in the day along the Tennessee border. Certainly cannot rule
out a few severe storms mainly over west Kentucky and southwest
Indiana. The consensus of guidance is that most if not all of
the convective activity will shift south of the area by early
Will have a dry forecast for the entire area overnight Sunday
through Monday Night. A deep trough over the Great Lakes and
northeast will keep the area in strong northwest flow aloft
through the period. North winds will bring much cooler and drier
air into the region through the period, as well.
.LONG TERM...(Tuesday through Saturday)
Issued at 255 PM CDT SAT JUL 26 2014
Above medium confidence in the extended.
High pressure aloft will be firmly in place over west with a
persistent upper level trough over the east. This will place in a
much drier northerly flow in the fronts wake. This will also result
in unseasonable low RH reading for most of the upcoming week. By the
end of the week the upper level trough deepens and even suggest a
cut off upper low forming the lower Tennessee Valley Friday into the
weekend. This will allow for at least daytime storm chances mainly
in the afternoon with max heating...but could not rule out some
activity into the evening hours.
Temperatures will much cooler than normal through the extended with
lower to middle 80s for the region.
Issued at 1235 PM CDT SAT JUL 26 2014
The main concern to aviation for this forecast cycle is the
potential for a complex of severe storms with damaging winds
pushing rapidly east southeast through KEVV and possibly KOWB this
evening and possibly overnight. At this time, forecast confidence
is quite low in this evolution, and there is a real possibility
that the storms will stay north and east of the terminals. Will
not insert TS in the TAFs at this time, as there should be ample
time to add it into the forecast when it becomes more obvious its
going to happen.