Upslope Event 1of 3 with Blizzard Conditions

December 10, 2025 7:31am

A BALMY morning relatively speaking if you are across the high ground and west. South winds blasting over the area along with some cloud cover.

Its colder in the panhandle of Florida this morning vs some of the high Alleghenies. Clear skies, calm winds there, that leads to a good night of radiational cooling east of the mountains and a bit further south. Let’s look locally at the east side vs west side of the Alleghenies. Cumberland 20s, Garrett County Airport near 40, Morgantown in the 40s. Thats calm, separating from the air mass aloft to the east. Meanwhile the disturbed air, associated with our incoming weather is in play over the high ground.

Cold east this morning, mild over and west of the Alleghenies

Now throw in some good snow-cover with those clear skies in the south east side of the Alleghenies and its even colder this morning. Teens vs mid 40s on the west side of the Alleghenies.

Not a unforseen or rare thing to watch that play out.

Courtesy of high pressure south and the low pressure of the clipper system coming across the southern. Great Lakes area.

Low pressure northwest-counter clockwise flow= southerly winds. In this case gusty southerly winds.

Its too warm to snow? Theres a pretty good lapse rate and more low level dry air in place. Meaning its colder as you go up, dry air has further room for evaporarational cooling. It can initially snow to the surface/graupel/snow pellets at 40°. Courtesy of dry air. That dry air is also a reason this morning at 40°, limited if any snow melt has occured. As the dry air moistens up at the surface and aloft, it helps lower the surface temps and as precip falls its also cooling the lower levels,,especially with any heavier rates. So initially the snow today above 2000-2500 will be a wet snow. 32-34° surface. Any lulls in action, temp may flux up a degree and with saturation the surface can even briefly melt back what has fallen.

K2G4 Garrett County Airport (2933′)vertical profile. Dry low levels this morning . Up a few thousand feet, temps below freezing.

as the low levels saturate they cool, as well as the surface gets down to near freezing as precip commences..

Above 3200-3500′ temps should come back down to and below freezing and no issues of tetering the freezing mark as it snows today. As we go evening in to the overnight and the winds shifting west, northwest colder air comes in. Snow ratios increases. A 10 to 1 today goes 20+ to 1 tonight. A lighter snow in terms of density and is mire readily blown about on strong winds gusting 40-50+mph. Thus conditions look doable of 1/4 or less visibility, 35+mph winds, with snowing and blowing occurring for 3 or more hours. We have had numerous like events in years past that have not been issued per the letter of criteria and now they are. So, to stress, its not the Blizzard of 93 coming. However poor conditions with whiteouts are expected.

Now let’s look at the 3 upslope event per the Euro

event 1 today and tonight in to Thursday

my thoughts for the current event remain unchanged. Lean low to mid range and a good performance can reach the top end

now off the Euro for event 1

Event 2 Friday-Friday night- more of a diver and weaker vs 1 and 3

Event 3 Saturday night-Sunday

3 systems by the time we get to Monday that may tally 10,12-20″ across the high ground. Being windblown, you will not have those amounts on the ground. Total snowfall accumulation for multi day and multi events is not the same as snow depth. Due to a variety of factors.

Frigid air late weekend, early next week looks to rapidly modify by midweek and lots of mixed signals as we head towards Christmas.