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FXUS61 KRNK 201315

Area Forecast Discussion
National Weather Service Blacksburg VA
915 AM EDT Sun Oct 20 2019

Remnants of Nestor track across the Carolinas this morning and
offshore by this evening. High pressure builds in for Sunday 
night, before sliding east Monday. A cold front will cross the 
Mid Atlantic during Monday night and Tuesday to bring the next 
opportunity for rain.


As of 910 AM EDT Sunday...

Radar still shows some heavier showers lingering east of the
Blue Ridge across VA with lighter rain/drizzle extending back 
further west and south. However, the precipitation will be 
gradually tapering off into early this afternoon as the remnants
of Nestor pull away from the region. This will allow for some 
partial clearing especially across the foothills/piedmont of NC.
Where the clouds linger most they will hold temps back a good 
it and make for a chilly day. 

Previous discussion...

Remnants of Nestor centered along the SC/GA border this morning
will track northeast to off the NC/VA coast this afternoon. 
Not expecting any excessive rainfall as bands of heavier rain 
moving at decent clip...and most will have beneficial rains. 

Temperature forecast tricky today especially in the piedmont where 
models have a slower exit to the lower cloud cover. Went a little 
cooler along/east of a Lynchburg to Danville to Reidsville line than 
ECM/GFS mos, but not as cool as NAM. Expect the sun to return to the 
foothills of VA/NC into the mountains this afternoon, with clearing 
east of Danville/Lynchburg after 5pm.

Will go with highs from the mid 60s to around 70 in the 
mountains/ around 60 east of Lynchburg-Greensboro line.

Tonight, airmass not changing much and with a moist ground/lack of 
wind today, will potentially see a foggy night for most, with model 
4cast soundings suggesting this after midnight, and/or low stratus.

Lows will be close to normal in the piedmont and above normal in the 
west, with readings in the upper 40s to lower 50s.

Forecast confidence is high on rainfall threat this morning, then 
sliding to average for sky cover and clearing later this afternoon 
and fog/low clouds tonight.


As of 300 AM EDT Sunday...

Looking to Monday, high pressure situated along the Appalachian 
chain will drift east while our next cold front approaches from the 
west off of a deep low pressure system over the Upper Midwest. 
Windflow ahead of the front will come from the southeast, drawing 
Atlantic moisture upslope into the mountains. As such, we can expect 
an increasing chance of showers beginning Monday afternoon, 
initially confined to the Blue Ridge Parkway area in northern North 
Carolina, but becoming more widespread on Monday night. Moisture 
flow into our area will increase significantly on Monday night as 
low level winds increase in speed, with precipitable water values 
lifting into the 1.3 to 1.6 inch range, which is well above average 
for late October. Have therefore increased rain chances for Monday 
night into the 80%-90% range for the entire forecast area. Also, 
given the heightened levels of low level wind shear and helicity, 
will be keeping an eye out for a storm or two becoming strong, 
capable of producing gusty winds, though the threat of this appears 
to be low.

The cold front will begin passing across our area shortly before 
dawn Tuesday, and rapidly progress eastward, reaching the Tidewater 
during the afternoon. Frontal passage will usher in a westerly 
windshift that will allow for clearing skies and drier conditions 
for the remainder of the day. High pressure will then gradually 
slide east from the lower Mississippi River Valley on Tuesday 
evening to settle across the mid-Atlantic by Wednesday night, 
allowing for rather seasonable temperatures under mostly clear skies.


As of 315 AM EDT Sunday...

High pressure will continue to drift east on Thursday, maintaining 
the trend of dry and tranquil conditions and near seasonable 
temperatures for one more day. Another active front will approach on 
Friday with increasing chances for rainfall persisting into 
Saturday. Details on timing and amounts are unclear at this time 
range with wide model variations.


As of 720 AM EDT Sunday...

Expect the rain to move out toward late morning west of the Blue
Ridge and by early afternoon in the east. Ceilings are going to
stay sub-VFR for most of the day in the mountains and along/east
of LYH/DAN with scattering of clouds expected at ROA/BCB by 20z,
then LWB thereafter and in the east around 22z.

Tonight's forecast becomes problematic and models are hinting at
fog and/or low stratus forming across most of the taf sites.
Will trend toward lower vsbys after 06z, as model soundings are
really shallow on the moisture, so stratus may be more when fog
lifts Monday morning. Still confidence is high that sub-VFR
happens, but could drop further into LIFR range at some sites by
12z Mon.

Northeast winds will be gusty this morning at LYH/DAN before
subsiding by early afternoon. 

Forecast confidence for the early part of the forecast is high
on sub-VFR but lower on variation between MVFR to LIFR due to
rain/drizzle as models hang onto moisture longer.

.Extended Aviation Discussion...

Any fog and/or low clouds should lift after 14z Monday. Another
cold front will bring the next chance of rain and MVFR 
conditions for Monday night into Tuesday. Dry weather and VFR 
conditions are expected by Wednesday. Some moisture may return 
by late Thursday into Friday.





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