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Area Forecast Discussion
National Weather Service Blacksburg VA
350 PM EDT Thu Oct 27 2016

A weak cold front will move through the region this evening. High
pressure will build across the region for Friday into Saturday.
Another weak cold front will move through the area Sunday. This
will be followed by high pressure until the end of next week along
with unseasonably warm temperatures.


As of 330 pm EDT Thursday...

The weak cold front continues to move through the region. The
short range and longer synoptic scale models have all done a good
job on indicating that the bulk of the lift/PVA and associated
shower activity was going to be this morning into the early
afternoon. That has indeed been the case, with showers and
isolated thunderstorms moving into the Alleghanys this morning,
then just scattered light rain showers traversing the eastern
portions of the area this afternoon. SPC still feels that there is
potential for thunder across the Piedmont, so have included an
isolated thunder threat east of the front for the next few hours.
However, latest SPC analysis shows little to no remaining
instability. So, the thunder threat could be removed very soon as
I have serious doubts that it will materialize, although a few
showers may linger across the southeast part of the Piedmont for
the next several hours.

Overnight, upslope clouds and a few sprinkles will be the main
story across the western areas, with clearing across the east.
There may be a period of low end gusty winds west of the Blue
Ridge through the evening, but the stronger 850mb winds are
lifting north of the area overnight. Given that the post-frontal
air mass is mainly continental Pacific, 850mb temps actually begin
to rise, not fall behind the front Friday. Clouds overnight and
turbulent mixing along with little to no cold advection should
yield temperatures well above freezing once again.

Clouds will decrease in the western mountains by mid-morning
Friday leaving most of the CWA clear by early afternoon if not
sooner. With greater insolation and slightly warming temperatures
at 850mb Friday, expect afternoon maximum temperatures to be on
par with readings experienced today, likely warmer across the
Piedmont. Bottom line is that temperatures will continue to remain
well above normal for the foreseeable future.


As of 230 PM EDT Thursday...

Surface high pressure will track south across the region Friday
night and Saturday. This high pressure system along with heights
increasing aloft will keep the region dry Saturday with high
temperatures warming 10F-15F above normal. Flow aloft becomes zonal
Sunday resulting in similar high temperatures as Saturday. Normal
high temperatures for late October range from the lower 60s across
the mountains to mid to upper 60s across the foothills and piedmont.


As of 300 PM EDT Thursday...

An upper level ridge centered over Texas will track east along the
Gulf states through most of next week. This ridge will keep the
region dry with any northern stream disturbances tracking east from
the Great Lakes to New England.  Boundaries from a few northern
stream systems may dip far enough south to increase clouds and have
a slight chance for rain for area north of I64 Sunday afternoon and
evening and again next Thursday afternoon and night.

Cool air will wedge south across the region Monday with temperatures
warming to near normal. This wedge will begin to erode Tuesday with
temperatures moderating 10F to 15F warmer 


As of 125 PM EDT Thursday...

Some showers and cloud cover is in place over the region associated
with an upper level disturbance. A weak cold front is also expected
to cross the area during the TAF period. Winds are expected to be
relatively light with the exception of some gusts at BLF. For the
short term, conditions will remain VFR with some low to mid level
cigs. Areas east of the mountains can expect to remain VFR through
the forecast. Those locations at elevation can expect at the minimum
MVFR conditions overnight. BLF should see a lower cloud deck
moving overhead this evening which will cause vis restrictions. This
will persist until after sunrise until enough heating takes place to
burn the deck off. Some guidance suggests that visibility at LWB
could become IFR late tonight, however, enough uncertainty exists as
to just as far the temp will drop this evening that it was left as a
tempo group. Any chances for fog will diminish shortly after sunrise.
Afterward, high pressure will dominate the region and VFR conditions
will prevail. 

Extended aviation discussion...

VFR conditions should persist through the next several days as high
pressure becomes the dominant feature for the region. Some
possibilities for MVFR and perhaps a shower exist for Sunday ahead
of another weak front, but models seem to be in disagreement with
placement and this feature may very well miss the region to the





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