Area Forecast Discussion
Issued by NWS Blacksburg, VA-- Remove Highlighting --
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FXUS61 KRNK 290824
Area Forecast Discussion
National Weather Service Blacksburg VA
424 AM EDT Fri Jul 29 2016
A persistent stationary front extended from eastern Virginia, into
the Ohio Valley and through the mid Mississippi Valley and Central
Plains. Little change in this weather pattern is expected through
Monday. The front may move south into the Carolinas on Tuesday and
.NEAR TERM /THROUGH TONIGHT/...
As of 400AM EDT Friday...
Weak short wave from the Maryland panhandle into central Tennessee
will generate isolated showers over the forecast area this morning.
Low level winds will become northwest as the axis of this short wave
move east and the associated surface low tracks toward New York.
NAM, local WRF and HRRR bring the showers and thunderstorms that
were along the Kentucky/Tennessee border into the western part of
the county warning area this afternoon,then east by 00Z/8pm. With
the overall northwest winds, the best probability of precipitation
will remain in the western county warning area.
Starting out with widespread low clouds and some fog this morning in
the west. Bufkit forecast soundings suggest that southeast West
Virginia counties may not clear out until late morning. This will
limit available instability when the precipitation arrives in the
500MB heights today will be slightly lower than past few days.
Models should have a decent handle on the temperature trends of this
air mass. Stayed close to MAV guidance for both highs today and the
minimum temperature tonight.
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
As of 230 AM EDT Friday...
An upper level trough will remain centered over the Great lakes this
weekend. Waves rounding this trough will bring a good chance for
showers and thunderstorms to the region each afternoon and evening.
Models are keeping the stronger dynamics north of the area, but with
ample moisture and instabilities, strong to severe storms are
possible with damaging winds being the primary threat. Torrential
downpours are also possible each afternoon with pwats remaining
well above normal.
Temperatures stay elevated at night thanks to high pwats with lows
from the mid to upper 60s west to lower 70s east. This weekend
should be at or just above typical late July values of lower to mid
80s west to around 90 east.
.LONG TERM /MONDAY THROUGH THURSDAY/...
As of 245 AM EDT Friday...
Belt of westerlies will be laying across the area Monday, with front
situated across the mid-Atlantic. Afterward the upper flow takes on
a more NW to SE orientation across our area as ridge builds over the
Central Plains. The front weakens but convergence along it to remain
through midweek. In addition, the upper pattern favors potential
ridge runners, where convective clusters form over the upper midwest
and shift southeast over our area.
Overall, will keep threat of showers and storms in the forecast all
periods but looks like Monday will have the better chance for
May see slight nudge downward in temps early but overall humidity
levels should stay the same, so no appreciable dry air expected thru
.AVIATION /09Z FRIDAY THROUGH TUESDAY/...
As of 145 AM EDT Friday...
Satellite pictures and surface observations indicated an
extensive area of IFR to LIFR ceilings from the central
Appalachians into southwest Ohio and much of eastern Kentucky.
High confidence these clouds will remain over that area through
sunrise this morning. Lower confidence how far east the stratus
will spread. Have MVFR to IFR ceilings in at KBCB and KROA after
08Z/4AM. Ceilings will lift after 12Z/8AM and will be VFR for the
rest of the day.
Scattered showers and storms with MVFR ceilings and visibilities will
be possible across the mountains after 18Z/2PM.
At 06Z/2AM KLYH was reporting LIFR ceilings behind a line of
strong thunderstorms. Medium confidence than ceilings will lift
back up to MVFR early this morning.
Extended aviation discussion...
The area will remain in a relatively active period for showers and
storms through Tuesday thanks to a persistent, nearly stationary
frontal boundary across or near our region. Outside of the
precipitation and during the daylight hours, VFR conditions are
expected. Within the heavier showers and storms, and during the
overnight hours sub-VFR conditions are more likely.