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Area forecast discussion 
National Weather Service Louisville Kentucky
250 am EDT Wed Jul 30 2014

Short term (now through thursday)...
issued at 245 am EDT Wed Jul 30 2014

Early this morning, dewpts were hovering in the mid to upper 50s so
think that the record low temps (lower 50s) will be safe July 30th.
With dewpt depressions becoming very low this morning, think that
some locations will experience a light patchy fog especially in
valleys and typical fog prone areas. Any fog that forms will
quickly burn off after sunrise.

The rest of the day will feature mostly clear to partly cloudy skies
and slightly warmer temps than yesterday. Expect high temps to
reach the upper 70s and lower 80s this afternoon. Also this
afternoon a shortwave will drop south in the broad upper trough over
the region possibly sparking a shower or isld rumble of thunder over
southeast Indiana to the Bluegrass region of Kentucky. This setup looks
very similar to tues but with precip extent possibly more south into
our region. Therefore did expand the 20% pops south a bit.

Tonight and thurs expect mostly clear to partly cloudy skies as
upper level troughing and sfc ridging continues. Low temps tonight
look to reach the mid 50s to low 60s with highs in the lower 80s for

Long term (thursday night through tuesday)...
issued at 300 am EDT Wed Jul 30 2014

A stagnant upper air pattern will feature continued ridging across
the interior Pacific northwest and troughing across the Great Lakes
and the lower Ohio Valley. Only towards Monday will the eastern
troughing relax, with slowly building heights commencing east of the
Mississippi River.

Expect dry weather Thursday with generally light winds and
temperatures ranging from the mid 80s to the lower 60s at night,
which will stay a few degrees below seasonal averages.

The GFS and NAM show a sharpening of the general troughiness over
the lower Ohio Valley as a weak shortwave descends south across the
upper Midwest on Friday. Despite the lack of Gulf moisture, isolated
to scattered afternoon and evening showers are possible Friday and
Saturday, as the position of the axis of the 500mb trough is
forecast to remain to our west through late Saturday. Our best
coverage, while still just scattered, will occur Saturday afternoon
and evening. Temperatures Friday and Saturday will not change much
from the previous day.

Drier air will arrive Sunday as the 500mb trough axis moves east and
surface high pressure builds east across Illinois and Indiana.
Mostly sunny skies with slightly lower dewpoints and warmer
afternoon highs are anticipated Sunday through Tuesday. Highs by
Tuesday will slowly rise towards the mid to upper 80s.


Aviation (06z taf update)...
issued at 100 am EDT Wed Jul 30 2014

High pressure building from the plains to the mid-Atlantic will
provide US with mostly clear/partly cloudy VFR skies and light
west/northwest breezes. Just enough low level moisture may combine
with subsidence over the area to create some light MVFR br at bwg
and Lex around sunrise.


Lmk watches/warnings/advisories...


Short term........ams
long term.........Jsd

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