40/70 Benchmark

Our snowfall def has not decreased any since 2007, I can tell you that.

Looks to back up what Will was saying...the more marginal areas, like Virginia, lower plains and lower terrain of PNW have decreased, while parts of NE have actually increased.

The percentages look a bit more optimistic for snowfall in the mid Atlantic than the text map. Strange that it implies that the mid ATL does better than SNE, too. Not sure I would hedge that way.

Nice, yea...just as I had thought. Last March was a nice catalyst for regression lol

Thanksgiving turkies drowning everywhere in the 1950s.....

Just as it does in typical warm air advection.

I could def. see the freezing of ponds being delayed as a result of global warming...that makes sense. I was just speaking strictly in terms of seasonal snowfall locally when I disputed the impact of global warming.

2008 also featured the two-pronged heavy event around that same date.

Given that the vast majority of warming, at least locally, is being observed with respect to nighttime lows, I would venture to guess that any decrease in snow cover days is more at the bookends of the season...in December and March. I would actually strongly favor December given seasonal lag and increased propensity for blocking patterns during the spring. In short, I would guess December is seeing the lion's share of a decease in snowcover days (sorry rev) over the course of the past 30+ years.

No. Looks like it is a park?

That was my original contention in the post that John replied to. What are you referring to then?

I would characterize 2010-2011, 2013-2014, and 2014-2015 as pretty good retention winters over the course of the past decade....even 2017-2018 in March. I think achieving a snowpack of near 3' in eastern Mass twice in a decade is at least average frequency, and probably above.

There is also a theory that since the polar region is warming fastest by far, that we may be more prone to high latitude blocking, but that is more nebulous. I know that Will had an interesting counter to that theory a few years back, but I can't remember what it was. The rest of the support for snowfall not decreasing much around here anytime soon is really isn't debatable.

Well, given that we are in the fall, its the earlier season...ie 2008-2009, 1975-1976.

Exactly. Great post.

When our mean snowfall begins to decline, let me know.

Well, I agree with all of that. I did not mean to imply that global warming means a greater percentage of the precipitation is snowfall. Absolutely there is more precipitation, ie more rain and snowfall. I also agree RE extremes, and said is much a few posts ago in this very thread. As far as the question of whether or not snowfall suffers during our lives...no one knows for sure, but what I will say is that the vast majority of the warming, at least in this region, has manifested in night time lows more than daytime highs....which I think tends to minimize the mitigating impact on snowfall. IE we are now radiating to 16, as opposed to maybe 14-15 degrees 50 years ago. I would venture to say that this would have less of an impact on snowfall than if the positive anomalies were being observed more with respect to daytime highs. This past January was wonderful illustration of this in that the month finished with positive departures, despite going weeks on end not breaking 40....the positive departures were achieved while we slept.

False in terms of snowfall, which is what I am referring to. Warmer? More Velocity saturation issues? Sure, however, snowfall has not and is not suffering and I have explained why I believe that to be the case. As far as whether snowfall begins to decline in our lifetime is anyone's guess, but I do not believe so.

Agreed.

Ida, though not as intense a hurricane, reminded me a lot of Camille in both track and extreme inland flooding far away from landfall. Sometimes these TC setups over the ECONUS can lead to much greater loss of life than the initial impact at landfall. Yea, Camille was def. a solid analog.

2008 is def. high on my list, along with 1975.

Just remember that mother nature is very skilled at keeping the ledger balanced...ie engineering a counter to negate all of these changes as best she can. IE With all of this increased baro from global warming, why don't we get a blizzard of '78 every season?! Velocity saturation. Why isn't all of the baro gone due to global warming!? Thermal gradient tightening. In the end, it means a change in distribution via less middling events and more big dogs.

Long after we are gone....I would argue that the additional warmth has actually increased baroclinicity thus far, as the warmth along with John's expanding Hadley Cell has pressed north. Catch 22 bc with the increased gradient comes more velocity saturation, so it's a give and take....but when you can neutralize said propensity for velocity saturation....BOOM. All we are left with is augmented baro and matches being lit. Higher stakes today.

Well, I mean, I'll take a CJ over January 2012.