506
FXUS61 KRLX 072326
AFDRLX

AREA FORECAST DISCUSSION
National Weather Service Charleston WV
726 PM EDT Sat Sep 7 2024

.SYNOPSIS...
High pressure brings another extended dry stretch, starting out
cool this weekend, then warming up during the week. A system
may bring the next hopeful chance for rain by next weekend.

&&

.NEAR TERM /THROUGH SUNDAY/...
As of 725 PM Saturday...

Other than dew points running higher, closer to central
guidance, the forecast is on track, with inherited lows already
at the bottom of the guidance envelop for tonight. Stratus
formation may interfere with frost formation in the northeast
mountains, where the frost advisory remains in effect.

As of 1240 PM Saturday...

Parcel trajectories off the Upper Great Lakes will keep a low level
moisture feed in the form of a stratocumulus field going through the
remainder of the afternoon and into the early evening with eastward
shifting high pressure cutting it off by late tonight. With a dry
airmass and in and clearing skies overnight, should see very
effective radiational cooling with much of the lowlands dipping down
into the lower to mid 40s, with some patches of 30s possible across
southeast Ohio. In the mountains, widespread 30s are likely with
some patches down into the lower 30s possible. Largely think the
lowland dew points will remain too high to support frost formation,
except for perhaps some extremely patchy coverage in Perry County.
In the mountains, particularly in mountain valleys with limited exit
drainage, cold air drainage should support patchy/areas of frost
heading into daybreak, although this may be limited by patchy fog.
Confidence is marginally high enough to go with a frost advisory for
Pocahontas and portions of Randolph and Webster County with this
potential.

Valley fog (perhaps even a bit outside the valleys across the north
where between a quarter and 1 inch of rain fell last night)
will be possible overnight, dissipating through 10 AM Sunday.

Sunday looks like another great day if you enjoy the transition
seasons, morning lows in the 30s to 40s warming up to afternoon
highs in the upper 60s to lower 70s with mostly clear skies. The
only potential weather related concern will be rapidly drying
afternoon dew points as we mix into a substantially dry (-40C at
H800) airmass during the afternoon. Currently have relative humidity
values forecast in the lower 20s to lower 30s, but could see some
teens, especially across the Middle Ohio Valley. Light winds will
minimize concerns for rapid fire spread, but any recent rainfall in
these areas will quickly be shifted back into the atmosphere via
evapotranspiration out of the vegetation.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
As of 145 PM Saturday...

With high pressure retaining residency overhead Sunday night,
another decent signal for patchy frost in the mountain valleys
will be present before dawn Monday morning. We then branch out
into another comfortably dry day, with afternoon highs closer to
normal for this time of year.

Temperatures are progged to warm back up into the upper 80s for
Tuesday as the surface high stretches eastward and upper level
ridging establishes itself over the Ohio Valley. Dry weather is
still retained under these circumstances. Afternoon RH values
dip back down into the 20s/30s starting Tuesday, which may begin
to impose fire weather concerns heading into midweek and beyond
as little to no rain is projected for our forecast area.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
As of 145 PM Saturday...

A repetitive forecast of hot and dry weather remains dominant
through the first two thirds of the period. Surface high
pressure slides off the New England coast by midweek, yielding
pressure height rises and resulting climbing temperatures. Dew
points remain fairly low during this time, which will impose
low humidity during the peak heating hours. While the wind
component looks benign next week, still think fire weather
concerns could become present as leaf litter grows more
bountiful.

A southern stream, and possibly tropical, disturbance takes a
northward pursuit into the Tennessee Valley late in the work
week, bringing the next hopeful opportunity for rain.

&&

.AVIATION /22Z SATURDAY THROUGH THURSDAY/...
As of 725 PM Saturday...

High pressure building into the area tonight brings VFR
conditions through Sunday, save for its clear, calm conditions
allowing dense valley fog to form overnight tonight. The fog is
most likely at EKN as is typical, but also likely to form at
CKB, PKB and CRW. The fog will form 08-09Z as the high builds in
and takes out the pressure gradient, but is also typical
overnight timing for fog formation. The fog will burn off and
the stratus lift 12-1330Z. There may be enough stratus
formation in the EKN-CKB area overnight to interfere with dense
fog persisting through the early morning hours there.

An afternoon cumulus field is not likely Sunday.

Light northwest surface flow this evening will become calm
overnight, and then light northwest again on Sunday, backing to
west across the north late. Flow aloft will be light northwest
through the period,

Winds northwesterly 5-10KTs with occasional gusts into the teens
this afternoon becoming light overnight.

FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 00Z MONDAY...

FORECAST CONFIDENCE: Medium.

ALTERNATE SCENARIOS: Fog formation could vary overnight tonight.

EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH:   TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW:    TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.

UTC 1HRLY       21   22   23   00   01   02   03   04   05   06   07   08
EDT 1HRLY       17   18   19   20   21   22   23   00   01   02   03   04
CRW CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    M
HTS CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H
BKW CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H
EKN CONSISTENCY  H    H    M    H    H    H    H    H    H    H    M    M
PKB CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    M
CKB CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H

AFTER 00Z MONDAY...
IFR/VLIFR river valley fog possible in the morning Monday
through Wednesday.

&&

.CLIMATE...
As of 1240 PM Saturday...

A dry airmass settling in to the region will allow for very
effective radiational cooling tonight and Sunday night. Daily
low temperature records may fall. Below is a table of forecast
and record low values for Sunday and Monday.

Forecast / Record Low Temperatures
------------------------------------------------
-                  Sun, 9/8    |   Mon, 9/9
------------------------------------------------
- Charleston  | 44 /  45 (1951) | 45 / 43 (1986)
- Huntington  | 42 /  44 (1956) | 45 / 42 (1986)
- Clarksburg  | 39 /  39 (1944) | 42 / 39 (1986)
- Parkersburg | 40 /  42 (1986) | 44 / 44 (1949)
- Beckley     | 39 /  36 (1951) | 43 / 33 (1956)
- Elkins      | 36 /  36 (1932) | 40 / 37 (1986)
------------------------------------------------

&&

.RLX WATCHES/WARNINGS/ADVISORIES...
WV...Frost Advisory from 2 AM to 9 AM EDT Sunday for WVZ522>524-526.
OH...None.
KY...None.
VA...None.

&&

$$

SYNOPSIS...MEK/TRM/JP
NEAR TERM...TRM/JP
SHORT TERM...MEK
LONG TERM...MEK
AVIATION...TRM

CLIMATE...JP