-- Discussion containing changed information from previous version are highlighted. --
184
FXUS61 KRNK 121706
AFDRNK

Area Forecast Discussion
National Weather Service Blacksburg VA
106 PM EDT Sun May 12 2024

.SYNOPSIS...
High pressure builds today with dry weather through Monday. The
next storm system arrives Monday night into Tuesday.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 904 AM EDT Sunday...

Key Messages:

1. Lowered Dew Points/RH Values this afternoon.

Water vapor satellite imagery reveals a complex upper level
system spinning across the northeast US with an associated upper
level trof over our region.

This will keep a deep northwest flow over our area today, which
will begin to relax late in the afternoon as upper level heights
begin to rise in the wake of the departing trof. The 12Z RNK
sounding shows an abundance of dry air in the lower levels, and
as a result, lowered dew point values into the 30s for most
areas. Wind gusts up to 30 knots in the higher elevation are
also possible.

Otherwise, little changes were made to the forecast with the
individual NBM members showing a small spread in forecast highs
today indicating high confidence with using this guidance for
temperatures today.

Tonight, high pressure works overhead with light/calm winds. May
start to cloud up late as warm advection high clouds work in
from the southwest. This will figure into the lows tonight as
clear skies at the onset of the evening with lighter winds could
drop temps faster and a few areas could see lower 40s, possibly
touching the upper 30s in the valleys of WV into the Alleghanys.

Forecast confidence is moderate to high.

&&

.SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/...
As of 230 AM EDT Sunday...

Key Messages:

1. Showers and storms possible late Monday into Tuesday and
Wednesday.
2. Warmer temperatures for the beginning of the work
week.

Ridging aloft and high pressure at the surface over the eastern US
will start the work week off with warmer temperatures. An upper
trough will advance from the central US into the Midwest by
Tuesday, pushing a cold front into the Mid Atlantic by the
middle of the work week, while the surface high shifts offshore.
South and southeasterly return flow around the high will
contribute to increasing moisture and warming temperatures ahead
of the trough, thus increasing instability in the area, which
in turn will increase shower and thunderstorm probabilities as
early as late Monday night/early Tuesday morning. The greater
chances for showers and storms will be late Tuesday, as the warm
front lifts northward and cold front approaches closer from the
west. This will continue through Wednesday, until the trough
has finally exited to the east by Thursday. Locally heavy
rainfall is possible from this system, as precipitable water
values exceed the 90th percentile relative to climatology
Tuesday into Wednesday.

Temperatures through this forecast period will be warmest on Monday,
cooler on Tuesday and Wednesday, given plenty of cloud cover and
rain.

&&

.LONG TERM /THURSDAY THROUGH SATURDAY/...
As of 245 AM EDT Sunday...

Key Messages:

1. Showers and storms possible again for the end of the work week.
2. Drier weather for Thursday.

The 500mb trough will exit the area and move offshore by Thursday,
and brief ridging will build back into the area, as a surface high
pushes in behind the cold front, resulting in drier weather for
Thursday. Another upper trough develops just east of the Rockies,
and again tracks eastward by the end of the work week. Southwesterly
flow aloft will draw moisture northward from the Gulf, increasing
chances for showers and possibly thunderstorms by Friday and into
Saturday. Uncertainty remains in the timing and evolution of this
system, and therefore in the locations and time frame of heaviest
rain for the forecast area.

Temperatures generally remain near normal through this forecast
period, with highs in the 70s in the west and upper 70s to low
80s in the east, and lows in the 50s and 60s.

&&

.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
-- Changed Discussion --
As of 105 PM EDT Sunday...

Early this afternoon, VFR conditions were reported at all TAF
sites and confidence is high that VFR conditions will persist
through the TAF period. While there is a small chance (less than
20%) that a brief period of MVFR or IFR conditions due to
localized fog will occur at KLWB early Monday morning,
confidence was too low to include it in the TAF.

Winds gusting to 15 to 25 knots during the afternoon will
subside around sunset and become light and variable tonight. As
High pressure drifts to the east of our area Monday, winds will
become south at less than 10 knots.

High level clouds will overspread the region during the pre-dawn
hours Monday and persist into Monday afternoon, but confidence
is high VFR ceilings will prevail through 18Z Monday.

 Extended Aviation Outlook...

Precipitation and sub-VFR ceilings and visibilities return to
the region as Monday night through midweek. Thursday should
return to VFR most areas with some lingering MVFR possible in
the mountains.
-- End Changed Discussion --

&&

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

&&

$$

SYNOPSIS...AMS/WP
NEAR TERM...PH/WP
SHORT TERM...AS
LONG TERM...AS
AVIATION...PH