Area Forecast Discussion Issued by NWS Blacksburg, VA
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000
FXUS61 KRNK 091349
AFDRNK
Area Forecast Discussion
National Weather Service Blacksburg VA
949 AM EDT Fri Jun 9 2023
.SYNOPSIS...
High pressure will cover the area today through Saturday with dry
weather and generally below normal temperatures. A low pressure
system into the central United States will move to the east Sunday
and Monday, bringing the next opportunity for numerous showers and
thunderstorms. Tuesday and Wednesday will bring lingering showers in
the mountains and warmer temperatures across the region.
&&
.NEAR TERM /THROUGH TONIGHT/...
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As of 945 AM EDT Friday...
No major updates planned for the morning forecast update. Have
primarily made minor tweaks to hourly temperatures, dew points,
wind speeds/gusts, and sky cover based upon the latest
observations and expected trends into the early afternoon.
Isolated showers and storms are still possible across the far
northeastern sections of the region this afternoon, but
confidence is not high.
As of 305 AM EDT Friday...
Best chance of precipitation today northeast of Lynchburg...
Upper low over the northeast United States begins to move northeast
today and tonight with slightly higher 500 MB heights over the Mid
Atlantic region, but still persistent northwest flow through a deep
layer. Smaller short waves continue to rotate around the low,
but main trough axis moves offshore tonight. Good agreement with
the pattern in the synoptic scale models.
Guidance has some low level convergence in central and eastern
Virginia this afternoon, so will have the best probability of
precipitation in the Virginia piedmont between 20Z/4PM and 02Z/10PM.
Small spread in the models as far as today`s high temperature. No
need to vary from the NBM numbers.
Once again, the surface wind will decouple this evening, becoming
calm to light and variable. Tonight high pressure will be centered
over the southern Appalachians resulting in ideal radiational
cooling conditions. Similar to the range in temperatures this
morning, deeper valleys in the mountains will be colder than the
nearby ridges. Surface dew points mainly in the 40s will lead to
another night with below normal temperatures.-- End Changed Discussion --
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.SHORT TERM /SATURDAY THROUGH MONDAY NIGHT/...
As of 320 AM EDT Friday
Showers and thunderstorms possible Sunday and Monday...
The upper level low over New England finally starts to shift
eastward and farther away from the area by the middle of the
weekend, and upper level flow will start to become more zonal over
the region. At the surface, high pressure will remain situated over
the Mid Atlantic through Sunday morning.
A surface low over the Great Lakes with an attendant frontal
system will advance towards the area by Sunday, and the
southerly flow ahead of this front will advect warmer and
moister air to the central Appalachians, a change from the
recent stretch of dry days. Rain showers and thunderstorm
chances begin to increase by Sunday afternoon as the warm front
lifts northward into the area, and really ramp up Sunday night
into Monday.
The associated cold front will push eastward by Monday, increasing
coverage of showers and possible storms from west to east. Winds
are expected to be strong and gusty for Monday as the front
crosses, given 850 mb winds of 40 to 50 knots and the strong
pressure rises behind the front. At this time, the front looks
to be across the area by late Monday into Tuesday, although some
lingering upslope showers cannot be ruled out.
Temperatures will be trending warmer through the weekend, but Monday
will be a few degrees lower, as cooler air works its way into the
region behind the front.
Forecast confidence is moderate to high.
&&
.LONG TERM /TUESDAY THROUGH THURSDAY/...
As of 335 AM EDT Friday...
Near normal temperatures with chances of showers and storms
midweek...
The upper level trough will push eastward from the Great Lakes
during this forecast period, and the associated surface low follows
generally the same way. After the surface cold front crosses the
region late Monday into Tuesday, showers and storms should come to
an end as drier and cooler air pushes in, and Tuesday will likely be
one of the dry days of the next work week.
The upper trough and surface low look to dip southward into the
Mid Atlantic by the middle of next week, which could bring
another round of isolated to scattered showers to the western
slopes of the mountains.
Towards the second half of the week, a warm front will lift
northward from the southeastern US into the Carolinas. Warmer
and moister air with this feature will likely bring yet another
round of showers and thunderstorms from south to north. At this
time, this feature looks to reach the area by Thursday, but long
range models do show differences in timing and evolution of
this feature, which leads to lower confidence in this forecast
period.
Temperatures will be near normal through this forecast period, with
highs in the mid to upper 70s in the west, and low to mid 80s in the
east.
Forecast confidence is low to moderate.
&&
.AVIATION /14Z FRIDAY THROUGH TUESDAY/...
As of 635 PM EDT Friday...
VFR conditions are expected through the TAF period.
Upper low over the northeast United States begins to move northeast
today and tonight with slightly higher 500 MB heights over the Mid
Atlantic region, but still persistent northwest flow through a deep
layer. Smaller short waves continue to rotate around the low,
but main trough axis moves offshore tonight. Good agreement with
the pattern in the synoptic scale models.
Some fog has developed early this morning along the Greenbrier
River. Any impact on KLWB will be short-lived.
Guidance has some low level convergence in central and eastern
Virginia this afternoon, so will have the best probability of
precipitation in the Virginia piedmont between 20Z/4PM and 02Z/10PM.
The probability was too low to include in the KLYH TAF.
Once again, the surface wind will decouple this evening, becoming
calm to light and variable as high pressure will be centered
over the southern Appalachians.
Above average confidence for ceiling, visibility, and wind.
EXTENDED AVIATION OUTLOOK...
Mainly VFR conditions are expected through Saturday night.
Areas of sub-VFR are expected Sunday through Monday as a cold
front approaches and then crosses the region.
Aside from lingering showers on the western slopes of the
central Appalachians, Tuesday is expected to be dry and VFR.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...None.
NC...None.
WV...None.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS/DS
SHORT TERM...AS
LONG TERM...AS
AVIATION...AMS/RCS