TimB

May 9th has some of the hardest May records to break from both a cold and snow perspective. Record snowfall of 3.1” is much more than any other day in May, the record low max of 40 has been reached twice on the 9th and never on any other day in May, and 3 of the 4 times the May record daily mean temp of 35.5 has been reached have occurred on the 9th (including last year). But yes, we did get oh so close to that perfect setup to get a rare measurable snowfall in May for the 7th time on record.

CPC’s 8-14 day outlook seems to give us a shot at getting back toward normal for the month.

I could make a case for either one being logical and am genuinely curious where the meteorological community stands on that one.

Relative to 1991-2020. -1.9 relative to the 1981-2010 normals that were in place at the time. Regardless, we had a very warm back half of the month which is of course no guarantee this time.

Remember last year? We sure made a run for it and ended up less than two degrees below average despite the 2nd coldest first two weeks of May on record. And through one week of May we’re running 4.5 degrees ahead of last year. Today is warmer than last May 8th and tomorrow will be warmer than last May 9th, so I think below average is still more likely than above average when it’s all said and done, but never say never. Edit: of course that was a -1.9 anomaly against the normals that were in place at the time. Would have been a -3.0 anomaly against the new normals, since May is one of the months that warmed the most. This cold snap will be remembered maybe not for being brutally cold, but for its longevity. Even in that brutally cold first half of May last year, we never strung together three consecutive days where we didn’t get to 60. Today is day 4 of that streak. But we had some record cold last year and we’ll fall way short of that this year (though Wednesday’s record low of 33 is fairly soft and I wouldn’t rule out getting close to that).

Some runs of some models have us soaring into the 60s in the warm sector tomorrow night just before midnight (I’d bet on that based on climo). Otherwise I got nothing.

Probably accurate. Pittsburgh hit freezing on the 19th, 21st, and 22nd that year (only that late or later in 1963 and 1956, which I didn’t experience).

18z HRRR paints a nice localized but very impressive accumulation west of Chicago... Edit: and across northern Indiana into Ohio.

But it’s been 85 and sunny on several days already in a few places in this subforum. In my mind, cutoff low -> 80 and sunny -> cutoff low -> 80 and sunny -> cutoff low is not one but several pattern changes. There’s post after post about how dry it’s been in many locations this spring. That certainly doesn’t indicate a pattern of constant cutoff lows.

Guess what’s made it into the point & click for parts of Allegheny County.

Probably still perusing the data, particularly hour 300 and beyond of the GFS, and pounding his fists.

Don’t even, I’m dta1984’s sock puppet account.

Exactly. I’m actually going to go out on a limb and say half of those places I mentioned will probably hit 90 in May. Didn’t MSP hit 100 degrees in May during a “cold” spring a couple years back?

Summer always comes. I’m going to go out on a limb and say that IND, DTW, ORD, PIT, CLE, BUF, MSN, MKE, and DSM (am I missing anyone that posts in here?) will all exceed their long term averages for 90 degree days this summer. We’ll see.

To the extent that the GFS (or really anything beyond D10) can be trusted, the last couple runs continue to double down on the extent of the cold after the warmup. Then again, there were quite a few GFS runs that I remember painting a very warm, humid picture for the first half of May, 10-14 days out.

I would say a significant portion of people who post on weather forums, probably a majority, would classify ourselves as “odd ducks.” So the guy likes predicting what the weather will be like on holidays, months in advance, presumably for entertainment purposes, and then seeing if his forecasts based (I would assume) mostly on guesswork verify. A living, breathing, Farmer’s Almanac.

Oh God, the NAM is on board too.

Don’t get covid.

Well, I guess one run of one (somewhat inferior) model showing 5-9” of 10:1 snow along the US-18 corridor technically makes this event more likely than zero models showing it...

Shades of 1947.

Indeed, 73 people in this country got to see their normal temperatures go down.

Let the GFS finish.

Annual +0.6, September +2.0. I’m mostly talking about September, which for many of us is the month that’s been the most f***ed by AGW. UHI? Maybe some effect, but Pittsburgh’s airport is 20 miles away from the city (upwind, usually, at that), and at a higher elevation by several hundred feet.

10/150 = 7% 3/12 = 25%

The PTSD is strong with this one. Good thing it’s May and not January so there’s nothing to be bummed out about.