wxmeddler

Fresh (ie. still fluffy) snow is way more effective at longwave radiation emission than hardpack snow.

Even if Feb is normal, we would still be way below normal for DJF.

The dew points would indicate most of the area above the fall line could get to zero by morning if you have good snow cover.

Hi. I actually do meteorological instrumentation as my profession. Temperature measurement is are actually very reliable and is the easiest of the weather parameters to measure. The mercury thermometers made 100-200 years ago were very accurate (to within 1°F). As far as calibration, traditional ice water and a boiling water stove provide an accurate 2 point calibration that is still used today. Now is is true that modern thermometers are more precise. We can reliably measure temperatures to 0.01°F in laboratory settings and 0.1°F in natural settings. But for climatology that is all you need.

Really obvious where the heavier snow fell:

Heavily rimed snow / graupel in Silver Spring.

This is unfolding about how I thought it would. Maybe slightly more NW (30 -ish miles) than expected but that may change as we pivot and it comes east.

0z Euro pretty much aligns with my thoughts perfectly. 18z AIFS nailed my thinking though.

I'm just sitting here leaning on the Euro/EPS general 1-3. I think if a band sets up anywhere it will be Loudoun / N. MoCo / S. Fredrick / Carroll / N. Balt / York. Somewhere should get 6.

Yeah, it took a hot minute for it to saturate down.

Amazing

The H5 over upper midwest has been sheared out into a big + tilt trough, not what we're looking for.

More positively tilted and a bit of a wave disconnect in over the northern GL's at 90 hrs.

18z Euro Ensemble has some members with a tucked in surface low close to the coast at h120. Waiting on graphics.

1-3... "hmm" or "hey" Otherwise this is solid. 10+ for FOLKS seems like a decent threshold.