Saturday, March 23, 2019

Huge, Wet Vermont Snowstorm To Bring Arduous Cleanup, Increases Flood Threat

Here we go again. Digging out from another foot of wet, heavy snow
in St. Albans, Vermont. Seems that's all I ever do with my life in
the past couple years - just constantly dig out from giant,
 wet cemet snowstorms 
UPDATE 9 a.m. SATURDAY:

Some really spectacular snow totals have come in to the National Weather Service in Burlington as of 9 a.m.:

26 inches new was reported in Morgan, 25 inches in Lyndonville, 24 inches Danville and Walden.

There's lots of reports of 12-20 inches of new snow.

The high water content of this snow really makes this in many parts of Vermont one of the most significant late season snows on record.

PREVIOUS DISCUSSION:

The big snowstorm in Vermont will mercifully end today, but the heavy, wet snow will be backbreaking to clean up especially areas away from the deepest valleys.

Many of us, including me here in St. Albans, Vermont, got at least a foot of snow.

As of 5:30 a.m. it was an even foot deep at my house, on a hill away from Lake Champlain in St. Albans. And it was still snowing.

Which means the never-ending winter, when a snow cover was established in early to mid November, will go on for weeks more, as it will take a long time for this to melt.

As of early morning, no new summaries had come out yet of storm totals in Vermont since last evening. I'm sure there will be some pretty amazing numbers in the mountains. As of last evening, there had already been 18 inches of new snow in East Kirby, Cabot and Walden, Vermont.

More than a foot had fallen by 7 p.m. last evening in many towns at elevations of above 1,000 feet in northern Vermont. In many of those towns, it kept snowing all night. More than 2,000 people remained without power early this morning, mostly in northwestern Vermont where the snow really hit overnight.

Roadways, needless to say, are very bad in areas where it's still snowing. The western slopes of the Green Mountains and eastern parts of Franklin, Chittenden and Addison counties are particularly bad.

Very little of the snow will melt this afternoon, as it will stay cold even as the sun comes out. A brief thaw tomorrow won't get rid of much, and then it will be wintry cold again Monday, Tuesday and into Wednesday before it finally warms up.

Which brings us to something I alluded to as the storm began.  A flood threat. Warmer air will finally, at least temporarily reach us late in the week.  If the warmth lasts and increases, and then it rains, it will be real trouble.

This storm had a LOT of what would have been rain with it. Most places in Vermont got more than the equivalent of an inch of rain. Some places got the equivalent of two inches. As I mentioned on Thursday, there was already four to eight inches of rain locked in the snow pack at mid and higher elevations in and around Vermont, and up to ten inches of "rain" on the peaks.

This storm added one to as much as three inches of "rain" to the snow pack that will eventually have to melt. In the warmer valleys where rain fell during the first half of the storm, the downpours soaked the ground even more and created some runoff.

The bright side is after today there will be very little precipitation in Vermont through this coming Friday, but then, not much of the snow will have melted by then, especially in mid and high elevations.

If April turns out to be warm, stormy and wet, there is definitely the risk of at least some flooding. A worst case scenario is a storm in early to mid April that brings a surge of very warm, moist air and one to three inches of rain would cause serious flooding.

I don't see anything like that in the cards now, which is good. And, if we get an orderly melt, with lots of dry days, warm afternoons and chilly nights - perfect for surgaring - things won't be that bad at all.

Lake Champlain's level is already a little above normal - right around 97 feet above sea level as of yesterday.  Minor flood stage is 100 feet.

I'm almost sure the lake will reach minor flood stage. Just over 100 feet will cause minor beach erosion and flood the lowest lying shoreline places, like Perkins Pier in Burlington. However, a minor spring flood on Lake Champlain is actually a good thing. It's a natural cycle that keeps the ecosystem healthy.

If Lake Champlain flooding reaches 101 feet you start to get some real shoreline damage. I see that as possible this year but at this point rather unlikely.

We are also NOT in the same situation as 2011, when Lake Champlain eventually rose to a record crest of around 103 feet above sea level, causing millions of dollars in flood damage. Unless there is incredible, record rainfall between now and mid-May, we won't get close to that level of disaster.

I just don't see that happening.

In the meantime, for those of us who got clobbered by this storm, happy digging!


No comments:

Post a Comment