Text Products for AFD Issued by RNK

Area Forecast Discussion
Issued by NWS Blacksburg, VA
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000
FXUS61 KRNK 130536
AFDRNK

Area Forecast Discussion
National Weather Service Blacksburg VA
136 AM EDT Sat Apr 13 2024

.SYNOPSIS...
High pressure over the Lower Mississippi Valley will move east
across the Gulf Coast region as low pressure tracks through New
England. A cold front approaches the area from the Ohio Valley on
Sunday night and Monday with a low chance of showers. Temperatures
warm for the beginning of next week.

&&

.NEAR TERM /THROUGH TODAY/...
As of 120 AM EDT Saturday...

Per coordination with WFO GSP extended the wind advisory for
current county configuration through 6PM. MOS still running hot
for winds today. May see lull early this morning, but once the
sun comes up mixing will bring winds back to the surface with
healthy gusts anticipated through the afternoon.

Key message:

 -  Wind Advisory Remains in Effect

Upper trough remains over the forecast area. Until it exits the
region, the pressure gradient will result in windy conditions
with gusts up to 50 mph across the mountains and just lee of the
Blue Ridge.

Cloud cover lingers over the mountains this morning with a few
showers. The showers are expected to wane between now and
daybreak with clouds lingering until mid morning before
completely clearing. In general, expecting a mostly sunny day
but associated with a gusty winds. The winds are expected to
diminish at sunset...a much quieter night Saturday night.

Temperatures today will favor the seasonal norm with highs in
the 50s to near 60 mountains and 60s to near 70 for the
foothills and piedmont. Tonight will be clear but cool... lows
in the upper 30s mountains to lower 40s piedmont. Some of the
mountain valleys may dip into the lower 30s resulting in patchy
frost, but nothing anticipated elsewhere.


&&

.SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/...
As of 220 PM EDT Wednesday...

Key message:

  - Warming temperatures next week

Short wave comes through the northwest upper flow late in the day
Sunday, then back to upper ridging on Monday. 850 mb temperatures
warm back into the +12 to +14 range for Sunday and Monday.

Surface cold front drops down from the north but 850 boundary
remains north of the region. Wind speeds back to the west and
southwest ahead of the next short wave. Another period of gusty
northwest wind Sunday night before wind speeds drop of on
Monday.

Clouds and moisture increase ahead of the approaching front on
Sunday night and Monday.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
As of 115 PM EDT Friday...

Key Points:

1. Above normal temperature through the period.
2. Increasing probabilities of precipitation each day with the best
chances on Friday.

A look at the 12 April 00Z NCEP Ensemble Mean 500 mb Geopotential
heights shows the following scenario Tuesday through Friday. A
shortwave ridge is positioned over the area on Tuesday. On
Wednesday, a shortwave trough is expected to head northeast through
the Great Lakes region while the ridge over our region flattens.
Another, but more potent shortwave trough will be over the Northern
High Plains. On Thursday, this second shortwave trough reaches the
Upper Mississippi Valley. For Friday, this feature reaches the
Ontario/Quebec border with the base of the trough skirting the Upper
Ohio Valley and the US Northeast. Looking at the surface, low
pressure is expected to over the Upper Mississippi Valley on Tuesday
with an associated warm front extending eastward to near WV/MD/PA.
On Wednesday, the low shifts to the western Great Lakes region with
an associated cold front extending southwest into MO/NE/KS. There
are weak indication within the averaging process that a weak trough
may also be extending southeast into WV/VA/DE on Wednesday, likely
from the first upper shortwave trough noted above. On Thursday, the
low moves into Quebec/Ontario with the cold front extending
southwest into the Lower Ohio Valley. By Friday, the low is
approaching the Canadian Maritimes and the cold front moves over our
region.

Output from the 12 Apr 00Z Ensemble Situational Awareness Table
shows 850mb temperatures through the period around +12C to +13C
degrees across the region Tuesday through Thursday. These values
reach the 90 percentile of the CFSR 30 year climatology for this
time of year. For Friday, values decrease the +8C to +12C range.
Precipitable Water values Tuesday through Thursday are expected to
range from 0.75 to 1.00 inches, or values on the high side of
normal. Numbers decrease just slightly on Friday.

The above weather scenario should allow for above normal temperatures
across the region with progressively greater chances of
precipitation through Friday. Tuesday, some patchy light will be
possible across northern and western sections thanks to the position
of the warm front. Wednesday, coverage will be minimal, but not zero
across the mountains thanks to the glancing blow by the first
shortwave trough. The second system will progressively approach and
cross the area. Look for better probabilities across the mountains
on Wednesday. On Thursday, the best coverage will remain across the
mountains, but the entire region will see isolated to scattered
shower, and potentially isolated thunderstorm, coverage on Friday.
Isolated thunderstorms will also be possible on Thursday.

Confidence in the above scenario is moderate.

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
As of 130 AM EDT Saturday

Winds remain strong especially in the mountains. Winds are
expected to persist through the day Saturday before diminishing
at sunset.

Expect MVFR cloud bases in the mountains into Saturday morning,
with VFR east. By Saturday afternoon evening the western
upslope areas will clear out and return to VFR.

Forecast confidence is average.

OUTLOOK...

Sunday, VFR conditions are expected for all locations.

Monday, a weak system may bring a return of some showers and
patchy sub-VFR conditions to Southeast West Virginia. Elsewhere,
VFR conditions are expected.

Mainly VFR through Tuesday and Wednesday with a few
showers/storms possible north of KLWB.

Confidence in the above extended aviation scenario is good.

&&

.RNK WATCHES/WARNINGS/ADVISORIES...
VA...Wind Advisory until 6 PM EDT this evening for VAZ009-012>020-
     022>024-032>035.
NC...Wind Advisory until 6 PM EDT this evening for NCZ001>003-018-
     019.
WV...Wind Advisory until 6 PM EDT this evening for WVZ508.

&&

$$

SYNOPSIS...AMS/WP
NEAR TERM...PM
SHORT TERM...AMS
LONG TERM...DS
AVIATION...PM
National Weather Service Regional Headquarters
