Area Forecast Discussion
Issued by NWS Blacksburg, VA

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074
FXUS61 KRNK 151735
AFDRNK

Area Forecast Discussion
National Weather Service Blacksburg VA
135 PM EDT Sun Jun 15 2025

.SYNOPSIS...
A stalled frontal boundary will remain within the region through
this week. Several disturbances will move along the boundary,
resulting in showers and thunderstorms through the end of next
week. Slow moving storms could cause flash flooding, with
damaging wind gusts possible Sunday with the strongest storms.

&&

.NEAR TERM /THROUGH MONDAY/...
As of 240 AM EDT Sunday...

Key Messages:

1) High confidence for widespread rain in the form of showers
and thunderstorms beginning this afternoon through this
evening.

2) A few storms could be strong to severe, along with a threat
for very heavy rainfall resulting in flooding.


A backdoor cold front is progged to shift south across our
northeastern sections through the afternoon. This will put part
of central VA/S. Shenandoah Valley in a high pressure wedge,
with easterly winds developing over NE sections of the forecast
area. This wedge front will help enhance cells training along
it and to the south, and suppress activity to the NE.
Anticipating cells with moderate to heavy rainfall, with recent
RAP analysis showing PWAT values now closing in on 2.00", which
will be close to daily the maximum. Areas in the southern
Shenandoah and along and east of the Blue Ridge are
particularly sensitive from already receiving several round of
heavy rain from the past few days.

Severe storms look isolated given lack of shear, however plenty
of instability may compensate and produce a severe cell or two
with damaging winds, particularly east of the Blue Ridge. Weak
winds through most of the atmospheric layer will result in only
marginally favorable lapse rates. Bulk shear around 15-20 kts
and 0-1 km shear of only 5 knots or so will not support more
than single cell development, eventually merging into multicell
storms. Storm motion looks to be about 15 kt or less. These
factors reinforce the concern for heavy rain and training cells
possibly resulted in flash, areal, and urban and small stream
flooding.

Storm threat continues tomorrow, but coverages appears to be a
little less due to lack of forcing. However, high moisture will
remain in place and storms will be capable of very efficient
rainfall rates, which could lead to flooding.

&&

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
As of 1230 PM EDT Sunday...

Key Points:

1. Daily chances of showers and storms, with locally heavy rain
possible.
2. Temperatures trending warmer with values 5 to 10 degrees above
normal by Thursday.

A look at the 15 Jun 00Z NCEP Ensemble Mean 500mb Geopotential
Heights shows for Monday night the nose of a ridge axis across the
SE US, with an addition region of high pressure over the SW US. A
weak trough axis will be over the Mississippi Valley. A closed low
will centered over northeast Canada and another will be over the
Gulf of Alaska. A shortwave trough will be over the Pacific
Northwest. For Tuesday/Tuesday night, the trough over the Mississippi
Valley lifts northeast into the Ohio Valley, and the trough over the
Pacific Northwest heads into the Central/Northern Plains. The SE US
ridge remains in place, as so does the Gulf of Alaska and northeast
Canada closed lows. For Wednesday/Wednesday night, the Lower Ohio
Valley trough washes out within southwest flow across the mid-
Atlantic region. The Plains trough progresses into the mid to upper
Mississippi Valley, and the ridge axis remains over the SE US.

At the surface, on Monday night, high pressure will be over the SE
US and also over New England. Between the two a frontal boundary is
expected to extend from roughly the mid-Mississippi Valley, east
into the mid-Atlantic region. By Tuesday/Tuesday night, the front is
expected to make slow progress northward. High pressure remains over
the SE US, and low pressure begins to develop over the Central
Plains. By Wednesday/Wednesday night, high pressure remains over the
SE US with a baroclinic zone situated from the Central Plains to mid-
Atlantic region.

A look at the 15 Jun 00Z NAEFS Ensemble Situational Awareness data
shows 850mb temperatures Monday night into early Tuesday are
expected to be within the +16C to +17C range. By late Tuesday into
Tuesday night, values inch up a bit to around +17C to +18C. On
Wednesday, increase to around +19C to 20C over the region. These
values correspond to the 90 to 97.5 percentile of the 30-year CFSR
climatology.

The NAEFS Mean Integrated Water Vapor Transport is offering the
period of Tuesday afternoon through early Wednesday morning as a
window of opportunity for generous moisture flux across the area.
Values during this period for most of the region increase into the
90 to 97.5 percentile of the 30-year CFSR climatology. The
southeastern sections of the area have the best flux, reaching the
97.5 to 99 percentile during late Tuesday afternoon and evening.

The above weather patterns offer the following forecast. With high
pressure stationary to our southeast, the region will continue to be
within a pattern with southwest flow providing warm/hot and humid
conditions. Daily chances of showers/storms are expected. Chances
will be highest, with the greatest concentration of potentially
heavy rain, on Tuesday/Tuesday night with a w-e oriented frontal
boundary situated over or just north of the region as a focus for
development, especially given the well above normal water vapor flux
across the region noted above.

Temperatures are expected to trend warmer each day with Thursday
averaging around 5 to 10 degrees above normal.

Confidence in the above weather scenario is moderate to high.

&&

.LONG TERM /THURSDAY THROUGH SATURDAY/...
As of 1230 PM EDT Sunday...

Key Points:

1. Robust showers/storms expected Thursday/Thursday night.
2. Slightly cooler and drier for Friday.
3. Return of heat/humidity for the weekend, perhaps with higher
heat index values as compared to mid-week.
4. Isolated/Scattered mainly late afternoon mountain showers/storms
for the weekend.

A look a the 15 Jun 00Z NCEP Ensemble Mean 500mb Geopotential
Heights shows a shortwave trough over our region Thursday evening. A
closed low will be situated between the Gulf of Alaska and the
Pacific Northwest. A high pressure ridge will be over the SE US and
SW US. For Friday/Friday night, the shortwave ridge will shift east
to over the Canadian Maritimes by Friday evening. Ridging is expected
across the central, SW, and SE US. A close low moves to over the
Pacific Northwest. For Saturday/Saturday night, the low over the
Pacific Northwest amplifies in a open trough with its axis as far
south as Baja California. Ridging continues across much of the
central and southeast US. For Sunday, the ridge across the eastern
US is expected to increase in geopotential height. The trough in the
west grows wider and shifts slightly to the east.

At the surface, for Thursday/Thursday night, a cold front will
approach then cross the region Thursday night. High pressure will
build into the region behind the front Friday/Friday night. For
Saturday/Saturday night, the high will remain over the region while
low pressure develops within the lee of the Rockies. For Sunday, the
high remains over the region, and a low pressure center/trough
expands over the central and northern Plains States.

A look at the 15 Jun 00Z NAEFS Ensemble Situational Awareness data
shows 850mb temperatures on Thursday around +17C to +19C, nw-se,
with the high end of this range within the 90 to 97.5 percentile of
the 30-year CFSR climatology. On Friday, values are cooler, within
the +16C to +17C range. For Saturday, values increase again to +18C
to +19C, e-w, with the top end of the range within the 90 to 97.5 30-
year percentile. For Sunday, values trend even higher, reaching
around +20C to +21C, e-w.  This equates to the Piedmont region with
the 90 to 97.5 percentile and the mountains within the 97.5 to 99
percentile.

The NAEFS Mean Integrated Water Vapor Transport is offering the
period of Thursday morning through Thursday evening as a window of
opportunity for generous moisture flux across the area. Values
during this period for most of the region increase into the 90 to
97.5 percentile of the 30-year CFSR climatology.

The above weather patterns offers the following forecast. We will
continue within a warm/hot and humid weather pattern with daily
chance of showers/storms trough at least Thursday/Thursday night.
Storms on Thursday/Thursday night may be robust with the passage of
the cold front.

Behind the cold front, high pressure will provide drier, less humid,
and slightly cooler conditions for Friday. However, the cooler
weather will be short lived as the center of the highs shifts
southeast. This will start the process over again of offering the
region a southwest warm air/moisture advection pattern. The expected
trend in the 850mb temperatures suggest temperatures warmer/hotter
than what would have occurred mid-week. We may see a few locations
across the far eastern sections of the forecast area have heat index
values approach the 100F mark on Sunday. With a warmer dome of high
pressure centered over/near the area, shower/storm development will
be reduced compared to mid-week. The best chances will be
late afternoon isolated to scattered coverage over the mountains.

Confidence in the above weather scenario is moderate.

&&

.AVIATION /17Z SUNDAY THROUGH THURSDAY/...
As of 130 PM EDT Sunday...

Mixed VFR/MVFR conditions across the region this afternoon. This
should continue outside of any thunderstorms that develop.
Storms this afternoon and evening will contain very heavy
rainfall and some gusty winds. IFR likely for brief periods
within some storms.

Storm intensity gradually decreases this evening and lingering
rain may continue through at least midnight, giving way to low
clouds and some fog. Sub-vfr seems likely overnight.

Clouds linger after daybreak and some MVFR clouds may continue
through at least noon on Monday.

Winds remain light through the period.

EXTENDED AVIATION OUTLOOK...

Stormy pattern remains in place through midweek, with afternoon
and evening storm chances each day bringing sub-VFR conditions
when over any terminal. Low clouds and fog possible overnight
each night.

&&

.RNK WATCHES/WARNINGS/ADVISORIES...
VA...Flood Watch until 11 PM EDT this evening for VAZ011-013-014-
     017>020-022>024-032>035-043>047-058-059.
NC...Flood Watch until 11 PM EDT this evening for NCZ004>006.
WV...Flood Watch until 11 PM EDT this evening for WVZ042>044-507-
     508.

&&

$$

SYNOPSIS...BMG
NEAR TERM...BMG/SH
SHORT TERM...DS
LONG TERM...DS
AVIATION...BMG