Simply put, it the snow doesn't have the time or opportunity to melt on the way to the surface. It is generally going to be a shallow (and relatively dry) warm layer when it snows at 40.
Right on 0.50” total precip.
0.19” fell as rain
0.31” and 1.7” snow equals a nice 5.5:1 ratio when it was snowing.
The HRRR/NAM Kuchera ratios weren’t far off.
HRRR was too dry from a distance, but it nailed the front end rain and the temps.
Feels like I have to go measure every half hour to make sure that I am able to report the max new snow depth.
Both the HRRR and NAM take us to 40 this afternoon.
Best case might be a 3/25/13 situation. 4” paste bomb on .5-.6” precip in the western DC beltway. Never dropped below 32.8. Started during the late overnight hours which helped.