756
FXUS61 KRNK 211844
AFDRNK

Area Forecast Discussion
National Weather Service Blacksburg VA
244 PM EDT Tue May 21 2024

.SYNOPSIS...
High pressure passing overhead to the east will provide dry
weather for most locations through tonight. Increasing moisture
pooling ahead of an approaching cold front will bring widely
scattered showers and thunderstorms for Wednesday and Thursday.
This activity will increase in coverage through the weekend as
the low pressure system tracks toward the eastern United States.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 215 PM EDT Tuesday...

Key messages:

   - Confidence moderate for isolated thunderstorms this afternoon
   - Confidence high for above normal temperatures today and tonight

Satellite imagery depicts scattered fair weather clouds across
the region this afternoon, with more pronounced development
along the higher ridges west of the Blue Ridge. Still, abundant
sunshine has allowed temperatures to warm into the upper 70s and
low 80s for the region as we approach maximum heating.

Rapid update weather models still hinting at the development of
a few showers and isolated thunderstorms developing across the
mountains after 4 pm. This activity is expected to remain
progressive, resulting in relatively brief periods of rainfall,
with mainly a tenth of an inch or less in accumulation where it
does manage to develop.

For tonight, any showers and storms will fade quickly with the
loss of daytime heating as sunset approaches. With light winds
and mostly clear skies overtop moist soils from recent rainfall,
patchy fog will redevelop after midnight, particularly in the
river valleys. Overnight lows will bottom out in the mid 50s to
around 60 degrees.

For Wednesday, winds will shift more from the south as high
pressure moves away and a cold front approaches from the west.
Will start the day with fog burning off quickly and otherwise
abundant sunshine. By mid afternoon, expect another round of
widely scattered showers and thunderstorms to develop, mainly
for the mountains. Afternoon highs will be a few degrees warmer
than todays, reaching into the upper 70s to the mid 80s
areawide.

&&

.SHORT TERM /WEDNESDAY THROUGH FRIDAY NIGHT/...
As of 130 PM EDT Tuesday...

Key Messages:

1. Daily chances of showers and storms through the period.
2. Locally heavy rain possible Thursday and Friday.
3. Temperatures near to just above normal.

A cold front approaches the Mid Atlantic from the west by late
Wednesday into Thursday, and will bring unsettled weather to the
area through the end of the work week. This front stalls over
the eastern US, resulting in near daily chances of showers and
thunderstorms, highest chances along and west of the Blue Ridge
on Thursday and Friday as mid level shortwaves track across the
area. Precipitable water values will increase as the front
continues to move closer to the area, with forecast values near
or exceeding the 90th percentile relative to climatology. With
these above normal PWATs, there is potential for locally heavy
rainfall. There is a marginal risk for flooding by the end of
the week with the multiple rounds of rain expected, especially
over areas with saturated ground from recent rainfall.

Widespread cloud cover and rain Thursday will limit potential
for severe thunderstorms, but instability is forecast to be
higher on Friday, so there are higher probabilities for
thunderstorms by Friday. However, it is too far out to
determine mesoscale details at this time, so confidence at this
time is lower on convective development by the end of the work
week.

Temperatures will be above normal, but clouds and rain will
moderate daytime temperatures through the period. Overnight lows
will be mild.

&&

.LONG TERM /SATURDAY THROUGH MONDAY/...
As of 130 PM EDT Tuesday...

Key Messages:

1. Continued chances for rain and possible storms.
2. Slightly cooler temperatures over the weekend, cooling to
below normal by midweek.

Through the Memorial Day weekend, a frontal boundary will
meander and stall over the eastern US, and an upper shortwave
tracks eastward from the central US, which will continue the
chances of unsettled weather through the period. While the
weekend doesn`t look to be a total washout, there are daily
chances of showers and thunderstorms each afternoon and evening.
However, differing model solutions on the progression, or lack
thereof, of the front, brings uncertainty and thus lower
confidence in the details on timing of the precipitation.

A 500mb trough moves towards the region during the first half
of the work week, and looks to deepen as the surface low moves
over the Great Lakes. As the upper flow transitions to more
northwesterly behind this system, temperatures will cool to near
to below normal by the middle of next week.

&&

.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
As of 220 PM EDT Tuesday...

Expect VFR conditions to remain predominant through the
remainder of Tuesday. May see localized and brief periods of
MVFR/IFR visibilities in rainshafts where any showers &
thunderstorms develop this afternoon and evening. Coverage will
remain isolated to widely scattered, confined mainly to the
mountains. Any convection will dissipate by 22/01Z.

Expect another round of patchy IFR to MVFR fog to develop
across the entire region overnight given mostly clear skies,
light winds and moist soil conditions. With another day of
strong heating expected for Wednesday, fog will dissipate
quickly after 22/12Z.

With high pressure shifting toward the coast, winds will shift
increasingly from the south, allowing moist air to gradually
return to the region. Another round of widely scattered showers
and a few thunderstorms will begin to develop across the
mountains by 22/18Z.

Average confidence for ceiling, wind, and visibility.


EXTENDED AVIATION OUTLOOK...

VFR conditions will continue into Wednesday with the wind turning
to the southwest. The chance of showers and thunderstorms will
gradually increase in the mountains by Wednesday afternoon and
become more widespread by Thursday as a front arrives.

This front will stall by Friday across the Mid Atlantic and
linger through Saturday. Waves of low pressure riding along this
boundary will spark more showers and thunderstorms and increase
the likelihood of low ceilings during this time.

&&

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

&&

$$

SYNOPSIS...NF
NEAR TERM...NF
SHORT TERM...AS
LONG TERM...AS
AVIATION...NF