Bluefield, West Virginia 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

827
FXUS61 KRNK 090155
AFDRNK

Area Forecast Discussion
National Weather Service Blacksburg VA
955 PM EDT Tue Oct 8 2024

.SYNOPSIS...
Cooler and drier air settles in as high pressure builds in for
much of the coming week. This will result in perhaps an entire
week without rain, with temperatures near or a little below normal.

&&

.NEAR TERM /THROUGH WEDNESDAY/...
As of 950 PM EDT Tuesday...

Again, no major changes are expected for the latest forecast
update. Skies continue to be clear with calm or light and
variable wind. No river valley fog has developed, yet. However,
we are expecting development closer to daybreak, especially
along sections of the New and Greenbrier Rivers.

As of 645 PM EDT Tuesday...

No major changes are planned for the early evening forecast
update. Skies are clear, and winds are calm or light and
variable. Have made minor adjustments to the hourly temperatures
and dew point values to better reflect the latest conditions and
expected trends through the late evening.

As of 200 PM EDT Tuesday...

Key Message:

- Repeat of conditions from Monday: Cooler and drier weather with a
chance of isolated fog near rivers and lakes early Wednesday morning.

Clear skies and autumn appropriate temperatures will continue today
and into Wednesday evening. Tonight`s lows will be similar to Monday
night with low-40s west of the New River Valley and mid to upper-40s
to its east. Lower temperatures can be expected at higher
elevations. Wednesday`s highs will only be a few degrees warmer than
Tuesday with highs in the lower-70s towards the Piedmont and in the
mid to upper-60s towards the New River Valley. Winds will be
relatively calm over night, providing another chance of isolated
fog near rivers and bodies of water. Northwesterly winds will
pick up by Wednesday afternoon and be around 5-10 kts with
higher gusts towards the mountains.

&&

.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY NIGHT/...
As of 1200 PM EDT Tuesday...

Key Messages:

1. Dry through the period.
2. Trending colder.
3. Frost possible in the mountains Thursday night into Friday
morning.

A look at the 8 Oct 00Z NCEP Ensemble Mean 500 mb Geopotential
heights shows a closed upper low centered over Quebec/New England
Wednesday night. While model averaging does show a clear distinct low
center, its associated trough axis is washed out showing more of
oval or rounded height contours. There may be a hint of a trailing
trough axis extending southwestward into the eastern Great Lakes
region. The upper low is expected to head eastward and be near
Newfoundland and Labrador by Friday night. Across our region, flow
is expected to be either zonal or we will see a weak shortwave ridge
over our area. To our south, a trough axis may be along the coast of
SC/GA. At the surface Wednesday night into Thursday, low pressure
will be situated over the Canadian Maritimes with its associated
cold front extending south into the western Atlantic. High pressure
will extend from eastern Ontario south into the Lower Ohio Valley.
As we progress into Friday night, the high center to our northwest
will gradually head southeast and become centered over our region.

Output from the 8 Oct 00Z Ensemble Situational Awareness Table shows
850mb temperatures averaging +8C to +10C over the region on
Thursday. For Friday, values increase to closer to +10C to +12C.
Precipitable Water values Wednesday night into Thursday are expected
to average around or a little less than 0.5 inch. For Thursday night
into Friday, values drop to the 0.25 to the 0.35 range, placing most
of the region within the 2.5 to 10 percentile of the 30-year CFSR
climatology. Only a small increase is expected in values Friday
night.

The above weather pattern offers a rain-free forecast. Additionally,
with low Precipitable Water values, especially those expected
Thursday night into Friday, this may be a good opportunity to
undercut model guidance on dew point values, and thus allows the
potential for lower than guidance low temperatures. Clear skies and
relatively light winds should help maximize net radiational cooling.
Additionally, some of the higher elevated valleys Wednesday night
may see some patchy frost. A greater abundance of frost is more
probable for many areas along and west of the crest of the Blue
Ridge late Thursday night into Friday morning.

Confidence in the above weather scenario is moderate to high. The
biggest question mark is how much to undercut guidance and what
areas will have the best chance at frost, or possibly freezing
conditions in a few spots.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
As of 1200 PM EDT Tuesday...

Key Messages:

1. Trending milder through Monday.
2. Small chances of showers over mainly Southeast West Virginia
Sunday night into Monday.
3. Dry and slightly cooler for Tuesday.

A look at the 8 Oct 00Z NCEP Ensemble Mean 500 mb Geopotential
heights shows zonal flow over our area on Saturday with a shortwave
trough over the Dakotas. By Sunday, the trough over the Dakotas is
expected to have moved east and deepened notably over the Great
Lakes south into Mid-Mississippi Valley.  On Monday, the trough is
expected to deepen and amplify,and be situated near the spine of
the Appalachians. On Tuesday, the trough is expected to continue
amplifying, and be centered closer to the US East Coast. At the
surface, low pressure will head eastward trough southeast Canada and
an associated cold may resolve as a backdoor front for our region
Saturday night into Sunday, or at least approach our area from the
northeast. Sunday night through Monday night, low pressure will head
east through the Great Lakes region and arrive over the Canadian
Maritimes. An associated cold front is expected to cross our area on
Monday. By Tuesday, the cold front will be well to our east with
high pressure building into the region from the west.

Output from the 8 Oct 00Z Ensemble Situational Awareness Table shows
850mb temperatures area expected to range from +12C to +13C on
Saturday then +12C to +14C on Sunday. To top end of this range, over
western North Carolina, corresponds to values within the 90 to 97.5
percentile of the 30-year CFSR climatology. On Monday, temperatures
are cooler, falling through the day, reaching +2C to +5C by sunset.
By Tuesday afternoon, values are expected to average +1C to +3C
across the region, placing most of the area within the 2.5 to 10
percentile of the 30-year CFSR climatology. For Precipitable Water
on Saturday and Sunday, values are expected to average around 0.75
inch. For Monday into Tuesday, values again drop to readings at or
under 0.50 inch.

The above weather pattern offers a warming trend as the center of
surface high pressure shifts east, and a low pressure and its
associated cold front heads through the Great Lakes region. Both of
these transitions will allow prevailing winds to become southwest.
This pattern will advect both higher dew points and warmer
temperatures into the area. While a cold front is expected to cross
our area on Monday, moisture levels are not expected to have
recovered a lot. Currently we are thinking any shower activity will
be confined to western and northern parts of the area with not very
high probabilities of precipitation. Post cold front, a rebuilding
high pressure will quickly revert our forecast to a dry one.

Temperatures through the period will trend milder through Monday
before dropping off slightly on Tuesday.

Confidence in the above weather scenario is moderate.

&&

.AVIATION /02Z WEDNESDAY THROUGH SUNDAY/...
As of 715 PM EDT Tuesday...

VFR conditions are expected to prevail for most locations during
the valid TAF forecast concluding at 00Z Thursday/8PM EDT
Wednesday. The one exception will be some late night river
valley fog across the mountains. Have offered KLWB experiencing
some of this fog around daybreak Wednesday. Any sub-VFR
conditions should improve to VFR by a couple of hours after
sunrise.

Confidence in the above aviation forecast scenario is high.

Extended Aviation Discussion...

Canadian high pressure will dominate the region most of this
week. Outside of patchy late night/early morning fog with
increasing probability later on in the week, VFR conditions are
likely to prevail.

&&

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

&&

$$

SYNOPSIS...AMS
NEAR TERM...CG/DS
SHORT TERM...DS
LONG TERM...DS
AVIATION...CG/DS