Vinton, Virginia Weather Forecast Discussion

314
FXUS61 KRNK 211803
AFDRNK
Area Forecast Discussion
National Weather Service Blacksburg VA
203 PM EDT Sun Sep 21 2025
.SYNOPSIS...
High pressure will linger over the northeast U.S. into the
southern Appalachians tonight. Low pressure over the northern
plains and upper Midwest will track the Great Lakes and lower
Missouri Valley by Tuesday. This system edges closer through the
rest of next week increasing our chances for needed rainfall.
&&
.NEAR TERM /THROUGH MONDAY/...
As of 120 PM EDT Sunday...
Key Message:
1) Looking mainly dry into Monday morning.
2) A few showers/storms in the mountains Monday ahead of an
upper disturbance.
Low clouds and fog have transitioned into a scattered to broken
deck of cumulus this afternoon over most of the area.
Just enough low level moisture convergence across far SW VA to
spark a few showers this afternoon which may stretch into
southeast WV. Coverage overall should be isolated.
Pattern with the weak high wedge will likely bring a repeat
tonight of low clouds, patchy fog but not expecting any showers,
though a few could edge into our WV and far SW Va counties as
an upper disturbance moves into the central Appalachians.
Upper trough edges closer with southwest flow aloft and pieces
of shortwave energy shifting from the TN Valley into the
Virginias/Carolinas. Appears best moisture convergence will
stay west of us, but enough could reach the mountains to force
showers/storms to develop Monday mainly after midday. Best
lift/dynamics/shear stay west into KY so not expecting any
severe storms or flooding.
Lows tonight expected to be similar to last night with mid to
around 60 for most.
Monday, same as today, with clouds giving way to mix of
sun/clouds with highs in the mid 70s to around 80 west to lower
80s east.
&&
.SHORT TERM /MONDAY NIGHT THROUGH THURSDAY/...
As of 145 PM EDT SUNDAY...
Key Message:
1) Warm, moist, and rainy this week thanks to approaching cutoff low.
Wedging into the mountains will decline this week and residual high
surface pressure will remain. A cutoff low is still on track to make
its way from the Rockies into the Great Plains and then east.
Current model guidance puts the center of the cutoff low near the
border of Kansas and Missouri. Unfortunately, there is still a lot
of spread in the models of the exact next steps of this low. Best
assessment suggests the cutoff low will move slowly eastward with
the downstream wind portion of the low entering the Mid-Atlantic
around the latter half of the work week. A separate upper level low
over the Great Lakes may get absorbed by the cutoff low and there
very well could be several low pressure cores rotating around the
main system. Before the cutoff low arrives at our doorstep, it will
guide several perturbations into the Mid-Atlantic and provide
several rounds of showers and thunderstorms this week. Precipitation
chances are projected to be the highest for the whole area on
Wednesday and Thursday afternoons. A warm and humid trend will
assist in destabilizing the atmosphere. Air temperatures will still
be on the warmer side with highs reaching into the upper 70s to
upper 80s, but conditions will be noticeably more humid. Dew points
will be in the 60s for most of the region with parts of areas east
of the Blue Ridge reaching as high as 70F. For areas in the Piedmont
and southside VA, the heat index could be as high as 90F. PWATs
continue to trend upward and may reach as high as 1.25-1.75",
meaning your average thunderstorm will likely produce heavy rain.
How much rain can be expected will be dependent on how fast or slow
the cutoff low moves through the eastern United States. At this
moment, however, the Weather Prediction Center has a Marginal (Level
1 out of 4) Risk of excessive rainfall for the entire area on
Thursday due to this threat. Wind shear looks to increase as the
cutoff low moves closer, but it is still too early to know if this
atmospheric characteristic will co-exist with other favorable storm
parameters. The Storm Prediction Center has kept predictability low
for later this week to reflect the large uncertainties.
&&
.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
As of 145 PM EDT SUNDAY...
Key Message:
1) Model disagreement plagues forecast confidence.
Model agreement quickly erodes by this Saturday and there is a wide
variety of what the cutoff low will do in the extended forecast
period. The cutoff low will probably still be present somewhere in
the east coast by this weekend and likely provide another round of
showers and thunderstorms, but it is unclear whether the system will
stall or get dissolved back into the main westerly flow. The massive
uncertainty in this part of the forecast also means there is
uncertainty on when the cold front arrives into the area to possibly
bring a change in air and dew point temperatures. There is also
another issue. Global models are starting to pick up on a possible
tropical disturbance in the Atlantic (separate from Tropical Storm
Gabrielle which is not expected to make landfall). While the
National Hurricane Center only gives it a 40% likelihood of
developing into a tropical storm in the next seven days, the
evolution of the cutoff low may play a significant role in its path.
Again, there is still a lot of uncertainty and heavily assumes the
Atlantic disturbance will even become a tropical storm.
&&
.AVIATION /17Z SUNDAY THROUGH THURSDAY/...
As of 126 PM EDT Sunday...
Expect mainly VFR through this evening, but appears low clouds
and/or fog will again impact most taf sites with IFR or lower
cigs by 08-11z, then gradually improve to VFR in the 13-16z time
frame. Any showers look to be west of LWB/BLF through 18z Mon
but cannot rule out a rogue shower this evening out toward BLF.
EXTENDED AVIATION FORECAST...
Mainly VFR this week though could see some sub-VFR cigs/vsbys
with showers in the afternoon and fog at night mainly in the
mountains. Shower/storm chances increase by Thursday with sub-
VFR more likely areawide.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...None.
NC...None.
WV...None.
&&
$$
SYNOPSIS...VFJ/WP
NEAR TERM...WP
SHORT TERM...CG
LONG TERM...CG
AVIATION...VFJ/WP

NWS RNK Office Area Forecast Discussion