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000
FXUS61 KRNK 052339
AFDRNK

Area Forecast Discussion
National Weather Service Blacksburg VA
639 PM EST Fri Mar 5 2021

.SYNOPSIS...
High pressure will stay centered to our west but expanded into
our area through into this weekend. This will result in a
prolonged period of dry weather associated with cool
temperatures this weekend and warming temperatures next week.
There is a storm system over Texas that will move across the
Gulf Coast states through Saturday, but this system is expected
to remain well south of the region.

&&

.NEAR TERM /THROUGH SATURDAY/...
As of 630 PM EST Friday...

Tranquil weather tonight and Saturday.

Tonight, high pressure remains situated from the Canadian
Prairies to the southern Ohio Valley, ridging into our region.
An upper level trough tracking across the Gulf states will drive
convection over the southeastern states into Saturday. The
northern fringe of precipitation is not expected to move north
of the NC/SC border. With a persistent west-northwest wind,
cold air will continue to filter into the region. Overnight lows
will once again dip into the 20s across the area.

The upper level trough will be over the East Coast states
Saturday with a reinforcing shot of cold air. High temperatures
Saturday will warm into the upper 30s to mid 40s across the
mountains and low to mid 50s east of the Blue Ridge. Another
pressure gradient forms over the mountains to have another
breezy day.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY NIGHT/...
As of 130 PM EST Friday...

     Cold and Dry through the Period...

A deep upper level trough will linger over the northeastern U.S.
into Monday. A southern stream system will be shunted well to
our south moving from southern TX to southern FL through the
period. Thus, this system will have no impact on the Mid-
Atlantic or Appalachian region. A secondary surge of colder air
will spread across the region Saturday into Sunday as 850mb
temperatures within the base of the trough drop to around -10C
or so by Sunday morning. Low temperatures Sunday and Monday will
average about 10 degrees below normal with lows from the mid
teens to the mid 20s across the region. With near 100% sunshine
through this period, high temperatures will be chilly and below
normal but not too bad with 40s west to the 50s east. Only the
higher elevations above 3500 feet will see high temperatures
remain below 40 degrees.

By Monday the northeastern U.S. trough will lift out of the area
as the flow across the U.S. becomes increasingly zonal and a
short wave ridge drifts from the Midwest into the eastern TN/OH
Valley. 850mb temperatures will finally rise above 0C by Monday
afternoon reaching the +5C range or so by that time. Thus after
another very cold morning Monday with lows in the teens and 20s,
high temperatures will rebound to the 50s across much of the
area with 40s in the mountains.

Precipitation probabilities will remain at or near 0% through
the period with no upslope snow showers expected given the dry
northerly flow across the mountains for the weekend. Winds will
be a bit gusty on Sunday with the secondary surge of colder air,
but will subside Monday as the center of the Canadian high
pressure drifts over the region.

/Confidence Levels in Forecast Parameters/
High Confidence in Max/Min Temperatures through the period,
High Confidence in Zero Pops through the period,
Medium to High Confidence in Wind Direction and Speed through
the period.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
As of 205 AM EST Friday...

Confidence is high for an impressive warming trend.

A strong upper level ridge will build overhead on Tuesday, and
surface high pressure should drift offshore. As a result, the
Appalachian Mountains will experience a warm southwest flow
throughout this forecast period. Heights at 500 mb could exceed
580 dam by Thursday, and 850 mb temperatures may climb above +10
C. The warmer MEX guidance remains the preferred choice for
temperatures as the blended ensemble guidance is lagging with
this pattern change. Late in the week, the ECMWF tries to bring
scattered showers into the Mid Atlantic ahead of a low pressure
system in the northern Plains, but the GFS and the Canadian
models show nothing. Rainfall probabilities have been kept on
the low side due to concerns that the upper level ridge will cap
any development of showers and that

&&

.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
As of 635 PM EST Friday...

Terminals will be VFR through the period. Winds gusts will
subside some this evening, but remain 10 to 20 knots at the
highest elevations overnight.

A disturbance will move east across the southeastern states tonight
into Saturday. This system will bring high clouds into North
Carolina and southern Virginia, but with no precipitation.

As mixing begins Saturday morning, there will be enough pressure
gradient to bring back gusty conditions to the area. Once
again, gusts should not exceed 25 kts.

Above average confidence for ceiling, visibility and wind.

Extended Aviation Discussion...

Widespread VFR anticipated through the weekend and into early next
week.

A front approaching the Mid Atlantic region around Wednesday
will bring the next chance of precipitation and MVFR conditions.

&&

.FIRE WEATHER...
As of 635 PM EST Friday...

Poor humidity recovery expected tonight. The foothills of
Virginia and North Carolina may not exceed 60 percent.

A disturbance tracking across the southeastern states will
throw a blanket of clouds across the area tonight into Saturday
morning. These clouds will break in the afternoon. However, cold
air will continue to filter into the area with breezy
conditions developing by afternoon. Wind gusts should not
exceed 25 mph. Winds will subside in the evening as high
pressure builds into the region. Precipitation from this system
should not move north of the NC/SC border.

In spite of the recent wet pattern, fuel moisture is beginning
to trend lower, especially in western NC where precipitation
events have been somewhat muted compared to the rest of the
state. Wind gusts regionwide will be under 25 mph Saturday
which may pose control problems if burning grass. Leaf litter
and other surface fuels in direct contact with the ground will
likely contain higher moisture content due to the wet antecedent
conditions. The KBDI is well under 200.

&&

.RNK WATCHES/WARNINGS/ADVISORIES...
VA...None.
NC...None.
WV...None.

&&

$$
SYNOPSIS...RCS
NEAR TERM...RCS
SHORT TERM...RAB
LONG TERM...RAB
AVIATION...AMS/RCS
FIRE WEATHER...RCS/AMS