ALERT For Heavy, Wet Snow Accumulations At Highest Elevations Tuesday Into Tuesday Night With A Chance For Heavy Snow And Mixed Precipitation Into Middle Elevations

A southern tracking storm system will spread significant precipitation across the mountain area on Tuesday. Rain and mixed precipitation is currently expected to rule the low-middle elevations, below 3000 feet, with increasing amounts of heavy, wet snow at elevations above 3000 ft.

Update_1:30 PM on Tuesday_31 March 2020

*Very heavy snow has fallen and accumulated at the summit level of the High Knob Massif, covering roadways despite recent above freezing conditions. Travel is being discouraged along Route 619 and adjoining roads toward the summit level.

Although not as classic as some well documented past events, the bright banding signature did take its position along the High Knob Massif with heaviest snowfall along and southeast of the edge of this zone.

Snow that falls next will be associated with the comma-head of the upper level low, with dropping snow levels this evening as temps fall (but generally remaining at upper elevations with respect to sticking).

The Potential Exists For A Crippling Fall Of Heavy, Wet Snow At High Elevations In The High Knob Massif (Fast & Furious Fall)

Temperatures in upper elevation basins fell sharply through Midnight, with dewpoints in the 20s at the summit level where mass convergence is expected.

Some routes currently expected to be impacted include State Routes 619, and Routes 237, 238, 704, among some others, due to rates of snowfall greater than melting on above freezing surfaces.

The most favorable location for heavy snow will be the upslope zones along the High Knob Massif where air flow trajectories and the forecast thermal profile is favorable for formation of a *TIM Circulation (with a rain-snow line setting up on the northwestern flank of the massif in a Doppler radar indicated bright-banding zone).

*The major difference is this is now mid-spring. If a setting like this had developed during the winter I would have been predicting a massive fall of snow. Up to 6″ or more could still occur if a TIM Circulation develops at the upper elevations, such that this is a situation worth watching.

Otherwise, highest peaks on the Blue Ridge southwest to the Great Smokies will be favored, mainly at elevations above 4000 feet.

Snow levels will drop Tuesday afternoon into Tuesday night and the early hours of Wednesday morning, but sticking is expected to mainly be restricted to elevations above 3000 feet [(+/-) 500 vertical feet of error potential].

Longer-Term Persistence

The longer-term pattern is wanting to trend right back into the same type of regime that has made this year so wet, with more heavy to potentially excessive rainfall if this indeed becomes the observed pattern.