MN Transplant

I'm confused. The 1960s were excellent for snowfall. Remember that these are calendar years, not winter. 1960 33.0 1961 34.1 1962 28.7 1963 11.6 1964 27.9 1965 16.6 1966 44.3 1967 34.2 1968 8.2 1969 15.9 2013 4.4 2014 30.5 2015 18.3 2016 22.2 2017 5.3 2018 7.3 2019 15.9 2020 0.2 2021 5.4 2022 13.2

About that Calendar Year Single digit snowfall years 1884-1918 4 1919-1953 7 1954-1988 9 1989-2022 16

I'll take the challenge. My choices would make a stats professor cringe, but they crudely get the point across. Using daily data from DCA (downloaded from the Utah St. site), I calculated calendar year snowfall totals. I know the monthly and winter totals are available at LWX's site, but the use of daily snowfall lets us look a little more in depth. We actually have 139 years of data, which divides nicely into 4 quartiles of 35, 35, 35, 34. Across the board, the stats have fallen off. Calendar Year Average Median Years w/4" days Years with 6" days 1884-1918 22.8 23.4 29 14 1919-1953 16.3 14.9 27 16 1954-1988 18.5 14.7 25 14 1989-2022 13.3 10.5 17 12 And if you take a 5-yr running mean, and apply a basic trendline to that, woof. The trend is less steep if you remove the pre-airport location data (~1950), but it is still there.

NAM’d

5.4. Less than 3 degrees away from the coldest temp in the dozen years at my location.

DCA official 55/12. 43 degrees. Very impressive.

12/23/2022 joins the list. 55/15 so far.

55 is the climo high for DCA. We are going to be 40+ high to low for certain.

This is what winter looks like in my home area

I tried to take the top off the CoCoRaHS rain gauge and it was frozen solid. Ground is starting to get crunchy. Not yet on paved surfaces. 23.5. Max gust 37

Fully agree, and it is a very common occurrence around here. That said, there was so much rain that the ground is still “leaking”. I think at least the sidewalks will get real dicey once we get to 4-5pm.

It is the timing that is more rare. If this was happening in late January, it would be compelling, but not a massive story. Also, I posted stats last night that showed that the daily drop in DC will probably be top-5 in the last 30-40 years. We will also be setting low max records on Christmas Eve. That is very noteworthy.

31.8. Now we stay below freezing for a while.

Flurries and the breeze picked up

Mulch is whitening. That’s a win, right?

The cold air at the surface always lags due to the Apps

They probably do. The mesoscale models aren’t putting out massive short-term temp drops, though. Partially because we are going to step down to the low 40s before the front, and partially because the low level cold always takes it’s sweet time crossing the Apps. In the end, I think the daily number will look most impressive.

Fairfax County failed to pick up my leaves on time this year. I’m thinking that they are going to have a rough go of it if they try next week. Trying to find a good name for this soon-to-be-frozen pile. Leafburg? Rock Leafster? 1.94”, 52.9

NAM Nest joins the HRRR in keeping us below 20 on Christmas Eve. Still, a bit different from my home territory.

Front timing is still 9-10am along 95 tomorrow. HRRR a touch faster than the NAM. HRRR still more aggressive on the cold, but the NAM 3km is now <10 for most of us tomorrow night.

Heaviest rainfall rates of the day so far. Up to 1.42" total, 52 degrees.

More fun climo stats. There have been 68 days in DCA's climate record with a 40+ spread between high and low temps. Most of those are in the distant past. There have only been 5 cases in the past 40 years: 3/23/1994 - 83/39 1/19/1996 - 62/20 (the Potomac flood final push) 12/22/1998 - 67/24 4/8/2000 - 78/38 1/13/2018 - 62/21 We might be able to add to this list tomorrow if we can hold the 50s until midnight.

I think Christmas Eve has a solid chance of being the coldest December day since 12/22-24/1989 (17/5, 22/7, 23/10). Really just needs to surpass 12/20/2004 (24/11).

It looks like the HRRR is running 4-5 degrees colder than the other models, so 10 is a better forecast. Still, a pretty good situation to get DCA low since we aren’t counting on radiational cooling. My lowest December temp since getting my station in 2011 is 13. Should have no trouble beating that.