Showing posts with label Erie. Show all posts
Showing posts with label Erie. Show all posts

Wednesday, December 27, 2017

Severe Cold And Big Lake Effect Snows Will Probably Prompt Climate Arguments, Again

The six to 10 day forecast into the beginning of January
keeps the eastern United States quite cold. 
We're now in the heart of a long, long Arctic cold wave in much of the eastern two thirds of the nation that will close out 2017 and begin the first several days of 2018.

Wind chill advisories and warnings this morning extended from Montana to Maine and south as far as Kansas.

Locally, here in Vermont, winter chill advisories are up in the "warmer" valleys like the Champlain, and wind chill warnings are up elsewhere. It's too bad it's so cold: Ski conditions for the holiday week in the mountains are actually quite good. Better than most years.

Now that we've got the long, long, cold wave established and we're still getting those lake effect snows, activists who concentrate on climate change are going to be making noise again.

I'll give you the bottom line first, then the explanation:

For those of you who say all this cold and lake effect, deep snows are "proof" that the climate isn't warming, you're wrong.

For those of you way all this persistent cold and record breaking snows are signs of climate change, you're not wrong, exactly, but I think you could be overdoing it.

First of all, I have to give the usual statement before I dive into this whole thing: Individual weather events in small parts of the world are very rarely a clear signal of climate change, though they can be influenced by the phenomenon.

Also, to state the obvious, winter cold waves like this one have always happened with or without climate change. Arctic blasts in the winter are perfectly normal. As are lake effect snowstorms near the Great Lakes.

This is, of course, a very strong cold wave. International Falls, Minnesota had a record low of 36 below this morning, and the town of Cotton, Minnesota made if to 41 below.

As cold waves go, this one is covering a pretty big area, too. It goes most of the way across southern Canada, and covers, or will cover all but the southwestern 25 percent of the United States.

But in the grand scheme of things, even that vast cold area isn't all that big when you take the entire Earth into consideration.

So if it's cold where you are, you are not experiencing the whole world. You're freezing your ass off. That's not global warming. It's just bad luck where you are, if you hate cold weather.

Even though this cold wave will last up to two weeks in some places, that's not climate. It's weather. People always tell us to think of it this way, and it make sense: Climate is nature's personality, weather is her mood. In other words, good natured people are occasionally angry. Weather sometimes very briefly goes against decades long trends. No big deal.

Now, could this weather set up be a perverse symptom of climate change? Well, possibly, but there's a lot of more mundane things at work here, too.

Let's look at that epic, record shattering lake effect snowstorm in Erie, Pennsylvania, the one that dumped 60 inches of snow on the city in two days. Lake effect snows, as I've said, are normal. Cold air sweeps across the relatively warm waters of the lakes, easily picks up moisture and deposits that moisture on the shore as snow.

Lake effect storms usually arrange themselves in narrow bands. In the middle of these snow bands, it's a zero visibility blizzard. Five miles on either side of these bands, the sun might be shining. Often, but not always, these snow bands move north or south, east or west a little bit, depending on the prevailing wind, so no one place stays in the heavy snow.  
Erie, Pennsylvania was buried under 60 inches of snow
in two days. Photo by Greg Wohlford, Erie Times Union

Sometimes the snow bands do stay in one position. And if the wind comes from a direction that is most efficient at picking up moisture from the lake, the result is incredible amounts of snow.

That's what happened in Erie. The band of snow stayed positioned over the city, and the direction of the wind was perfect for manufacturing LOTS of snow.

So that's the main reason why Erie got clobbered. However, there is a legitimate climate change angle to all this. If the overall air temperature in the Great Lakes are warmer, despite the occasional cold snap, the lakes will be warmer, too. Warmer lakes mean more moisture can get into the air, making the lake effect snowstorms that much more intense.

Also, lake effect doesn't work if the lakes are frozen over. The cold winds can't pick up moisture from the lake water if that water is sealed off from the atmosphere by ice. As Climate Central points out, if it's an overall warmer winter, the lakes don't freeze as quickly, and you have more opportunities for lake effect snows on the occasions it does turn cold.

Now what about this extended cold spell? Is climate change influencing it? Well, it's possible, but certainly not definite. Cold waves lasting this long have always occured on occasion, so this isn't some weird unprecedented climate change disaster.

However, there is some scientific evidence that a relative lack of sea ice in the Arctic, as we are experiencing now, can help weather patterns in the mid-latitudes where we live get "stuck" so a particular kind of weather would last longer than it otherwise would.

It's been a very warm winter once again in the Arctic, so ice cover up there is below normal. That means it's within the realm of possibility that this cold wave here is lasting longer than it otherwise would.

I have no idea if that's actually the case right now, and I doubt any scientist yet knows, either. But it's definitely something for people smarter than me to study, to really understand if melting Arctic ice is messing with weather patterns much further south.

Meanwhile, stay nice and bundled up. You're going to be cold for awhile!



Tuesday, December 26, 2017

Into The Deep Freeze, For A Very Long Time

Increasing winds begin to blow powdery snow off of
pine trees Christmas afternoon after a morning storm left
six inches of new snow in West Rutland, Vermont 
We had a very nice Christmas morning snowfall here in Vermont, and a brief, but violent stormy burst around Boston with an hour long bout of gale force winds, super heavy snow, thunder and lightning.

All that Christmas fun is gone now, but we're in to the very, very deep freeze and it's going to last awhile from the Plains to the Northeast. And the Great Lakes effect snows are epic. More on that in a minute.

Here in Vermont, the temperature is going down, down, down. The cold wave will begin in earnest tonight, and last until, I'd say around January 5 or so. That's a long time.

The cold through January 5 will wax and wane over time, but it will be much colder than normal throughout. The first especially rough patch begins tomorrow and goes into Saturday. We're talking highs in the single numbers at best and lows in the teens below zero through the period.

The cold might relax just a tad over the weekend, then get super, super nasty again after that.

At this point, it doesn't look like we will be getting much snow through the period. Just a snow shower or interval of snow from time to time as reinforcing shots of Arctic air arrive from time to time.

An aptly-named business near Erie, Pennsylvania after lake
effect snows dumped an incredible 53 inches of snow on the
city over two days. 
The European weather computer models are still suggesting a nor'easter this weekend, but at this point, it looks like that storm will probably be too far south and east to give Vermont much of anything. It still bears watching, though, as it's possible it could still come close enough.

The most likely people to be affected by this potential storm are in far eastern New England.

After a warm early autumn, the Great Lakes are relatively warm and the contrast between that water and the frigid Arctic air is creating some epic lake effect snows.

Erie, Pennsylvania is really in the news today because of their epic lake effect storm. They had a least 53 inches of snow since yesterday. That sets a new record for the most intense snowstorm in Pennsylvania history. The previous record for that big a storm in Erie was in the 1890s, but it took 13 days, not two, to get up to 53 inches.

Erie has had 92 inches of snow so far in December (!!!!) Their annual average snowfall is 99 inches, so definitely, yikes!  They had as much snow in 36 hours as they normally do during the entire months of December and January.

Further north, in the famous snow belts in the Tug Hill Plateau near Watertown, New York, a lake effect storm total of up to six feet of new powder or more is expected by Wednesday night.

See? It could be worse here in Vermont. How would you like to shovel six feet of snow while it's 20 below?

We'll survive this.