Warm March Vermont Day; Snowcover Will Be Influence

Visible satellite photo of New England and eastern New York from Sunday.
You can click on the image to make it bigger and easier to see. Areas
with bare ground, including most of southern New England, southern
New Hampshire and the deeper valleys of southwestern and southeastern
Vermont will absorb sun, helping high temperatures reach well
into the 60s.  Snow covered areas will be cooler. 

We know today will be a very springlike mild day here in Vermont.

Most of us will get into the 50s, a few of us will touch at least 60 degrees.  That's fairly impressive, given that normal high temperatures this time of year are in the mid 30s to around 40.

The interesting thing for us weather geeks to watch today will be how snow cover influences temperatures.  Snow is a natural refrigerator.

The sun's heat gets bounced back to space to an extent where there's a decent snow cover.  Those places wouldn't get as warm as those that have no snow cover because the snow doesn't absorb the sun's heat very well.

The darker surface of the ground in snow-free areas absorbs heat more efficiently, so temperatures would be warmer there.

Most of Vermont was still snow-covered as of this morning.  But parts of the state have bare ground, mostly in the low elevations of southwestern Vermont and the floor of the Connecticut River valley from about White River Junction south.

There, today's sun will help temperatures skyrocket.  I wouldn't be at all surprised to see some highs in mid to upper 60s pop up today in places like Bennington and Brattleboro.  Some areas of snow-free southern New England could easily reach 70 degrees today.

In most of the rest of Vermont, highs will probably hold in the 50s, due to the chilling effects of the snow cover.

One computer model's forecast highs for today.  The areas shaded in
yellow and orange, depicting expected high temperatures at
or above 60 degrees, mirrors the snow free areas in
the satellite photos above. Blue areas in Vermont show
forecast highs in the 50s over snow-covered ground. 

A bit of a wildcard is the central and northern Champlain Valley.  In the valley, many open areas have lost almost all of their snow, especially from about Milton south.

However, wooded areas still have some snow cover, with some bare spots.  It's a mixed bag. The areas of bare ground will help heat the atmosphere, but the snowy woods would temper the warmth some. Still, it could easily hit 60 degrees around Burlington.

Further north in the Champlain Valley where I live in St. Albans, there's still quite a bit of snow on the ground, though there are large snow-free areas on open fields. The woods still have a fair amount of snow on the ground, especially away from Lake Champlain.  My guess is we'll make it to the upper 50s here.  

Right near Lake Champlain, wind blowing off the ice and very cold open water in the middle of the lake means people on the shores of the lake will see cooler temperatures than the rest of the region.

Today's warmth, though quite unusual for early March, won't set records, at least in Burlington.  On this date in 2016, the temperature reached 70 degrees in Burlington.  It won't get that warm today in the Queen City.

That balmiess on March 9, 2016 was briefly the earliest in the season on record for a 70 degree reading.  However, the very next year, the temperature reached 72 degrees on February 25, for a new early season record.

It'll remain on the mild side through Tuesday. But the expected clouds and light rain will make the sun's effects less of a factor. Temperatures will trend down toward near seasonal levels by the end of the week.

Entertaining Weather Videos On A Slow Weather Day

Clear skies in the Northeast Friday allowed a great view of where snow
was on the ground, where it wasn't, what was frozen, what not.
Click on the image to make it bigger and easier to see details.

Things have temporarily gotten slow in the weather department, but don't worry, things will be pretty active around here by the middle and end of the week.

While we have some quiet weather moments, some goofy weather videos to share. And a photo.

The photo on the right is a satellite shot taken amid unusually clear skies in the eastern United States on Friday.  Click on it to make it bigger and easier to see the details of the current state of the winter.

The snow cover in New England ends just over the Massachusetts border from Vermont and New Hampshire. The Great Lakes are remarkably ice-free for late February. Even the Finger Lakes in New York aren't frozen.

You can also see that a large section of Lake Champlain is also free of ice. It almost certainly will not completely freeze over this year.  We have a few warm days coming. Even if it turns cold in March, the increasing sun angle would help erode new ice that forms at night.

Down in eastern North Carolina and southeastern Virginia, you can also see an area of snow on the ground from a small storm the day before.  By the end of the day yesterday, that snow in the Southeast was mostly gone.

The clouds off the New England and Mid-Atlantic coasts are caused by cold air blowing over the relatively warm waters of the Atlantic.  There were even a few ocean-effect snow flurries from these clouds Friday morning on Cape Cod.

Now some videos:

This one has been billed as a "carbon neutral way to prevent ice dams:"



Next up, stupidity of the day.  We see this all the time. People drive right into floodwaters, not knowing how deep it is, not caring how dangerous it is.  A lot of it is stupidity.

There's still a lot of flooding going in in England due to two immense storms over the past couple weeks.  Here, we see rescuers in elaborate safety gear with boats heading out to retrieve residents from obviously deep floodwater in one neighborhood.

You and I wouldn't drive down that flooded street, right? The turbulent water and the rescue crews would seem like dead giveaways not to proceed.  Not everybody thinks like that. Watch the rescuers shake their heads in disbelief:



In Michigan, volcanoes have been erupting last week.  Don't worry, no lava in Detroit, no pyroclastic flows in Ann Arbor. Instead, ice has piled up on the windy shores of Lake Michigan.  More waves pounding in get under the ice and water pressure creates these "ice volcanoes."  They're pretty cool:



Also, in Michigan, another icy phenomenon.  A curving current in a small river created a rotating ice disk, much like that larger, more famous one that formed in Maine last year.  Here's the mesmerizing Michigan ice disk:

Snow Cover Extent Is Getting Weird In The Northern Hemisphere

The extent of snow and ice cover in the Northern Hemisphere during the
autumn has trended upward in the past 50 or so years, but.....
  

It's been a weird early winter for snow cover in Vermont and the rest of the North Country.

Where I live in St. Albans, tucked in the northwestern corner of Vermont, we have continuously had snow on the ground since November 13.

Which is really weird. The second half of November and early December usually have a thin snow cover off and on. Some days have no snow on the ground at all.

More often than not, you start to see a more consistent snow cover from mid-December on. Right now, the snow cover in my yard is the thinnest since November 16. And a warm, rainy storm forecast to hit Friday and Saturday will likely get rid of pretty much any snow that remains. Except for maybe a few drifts and snow banks.

This year's trend in northwestern Vermont is pretty much mirroring what is going on in North America as a whole, and has similarities to winter snow cover extent in the entire Northern Hemisphere.

North American snow cover extent this November was very likely the most widespread since at least 1966.  For the entire Northern Hemisphere, the snow extent in November was the third highest on record. These records go back 53 years.

But snow extent is really variable. Right now, in the grand scheme of things, latest maps from the Rutgers University Climate Lab show overall northern hemispheric snow extent to have settled into the near-normal category as of mid-December.

What's interesting from the Rutgers data is winter snow cover extent is all over the place during the winter. Some years, it's much greater than average, and in other years, it's much less.  There's no clear trend.

In the summertime, though, when snow and ice cover retreats to areas close to the North Pole, the extent of the snow and ice is consistently well below normal. 

........Spring snow and ice extent in the Northern Hemisphere has defintiely
fallen over the past five decades.  

Autumn snow and ice cover in the Northern Hemisphere has trended upward somewhat over the past 50 years and I've seen climate change deniers seize on that as helping "prove" their point that global warming is a hoax.

After all, if the world is warming, wouldn't there be less snow and ice extent?

Turns out, snow and ice extent isn't always the greatest measure of how the climate is changing.  Way back in 2014, the Washington Post Capital Weather Gang noticed the trend toward increased autumn snow cover in the Northern Hemisphere. They explained why this increased snow cover doesn't explain climate change:

"It simply needs to be near or below freezing for snow to fall. Temperatures that average 1-2 degres F above normal over the globe can still support snow in many places. Furthermore, slightly warmer than normal temperatures increase atmospheric moisture content, elevating potential snow amounts where they occur."

In other words, a storm that might have once been capable of producing three inches of snow in a given spot might now dump six inches of powder. It takes longer for six inches of snow to melt than it does for three inches, and that might be contributing to the increased snow cover in the North during the autumn.

It's possible, then, that climate change might, just might have something to do with the more widespread northern snow cover in the fall.

Interestingly, spring snow cover in the Northern Hemisphere is showing a noticeable decline over the past 50 years. That's important in terms of climate change.

The sun angle is higher in the spring than in the winter and fall. Snow cover tends to reflect much of the sun's heat back up to space. Bare ground absorbs heat, helping make overall temperatures higher.

Less extensive spring snow cover means more heat can be absorbed by the ground, thereby helping to heat air temperatures, creating a "positive feedback" for climate change.

Sunshine in the fall and winter does get reflected back to space on snow covered ground, too, and heat from sunshine gets absorbed by dark earth, but the effect is less pronounced because the low sun angle doesn't provide as much heat from the sun as you'd get in the spring.

Back here in Vermont, we know that snow cover locally can go up and down pretty quickly in the winter, with or without influences from climate change. Local, regional and national short term weather patterns dictate how much snow is in my back yard, and yours.

My yard in St. Albans, Vermont had more than a foot of snow cover on November 18 and a patchy inch or two now.

Who knows, within a couple weeks, I might be back up to a foot of snow on the ground, or more.  Winters here in Vermont always hold plenty of surprises.