Botched Vermont Forecast: "Rain Storm" Turn Into Snowy Mess

 Boy, forecasters got this storm wrong. That "rain" out there in Vermont this morning is looking awfully white. 

Route 100 near Warren, Vermont
overnight. Photo via Facebook by
Enrique Melendez. 

Instead of a mostly rain event, heavy wet snow clogged highways throughout Vermont along with widespread power outages. The commute to work that was supposed to be easy was a mess for many people.  

Now that we woke up unpleasantly surprised, the storm is mostly over. 

The National Weather Service in South Burlington, when it became apparent that this was a snowy surprise, last night issued a winter weather advisory for northern Vermont away from Lake Champlain. 

In hindsight, it probably should have been a winter storm warning. As of 7 a.m. this morning 34,000 homes and businesses across Vermont had no electricity. This is yet another big hit for the state's electric utilities, who have suffered widespread storm damage with increasing frequency in recent years.

Many roads and highways were closed by fallen trees and power lines and stuck cars. 

 I have no clue whether climate change helped intensify last night's storm, but other storms that have causes widespread power failures in Vermont in the past decade were probably turbo-charged at least a bit by climate change. 

Snowfall totals from overnight are pretty impressive. Especially considering it was a heavy, wet snow that doesn't pile up as readily as powdery stuff. 

We don't have a complete list of totals yet, but I see reports of 9.5 inches in Calais, Duxbury and East Warren; 9.0 inches in Cabot and Standard; 8.0 inches in Waterbury Center and 7.5 inches in Worcester.

Even parts of the Champlain Valley, which were forecast to receive absolutely no snow, got at least a little.  There's a good inch of new snow on the ground here in St. Albans. However, most of the snow in the valley was mixed with a drenching rain. Places around Burlington and right near the lake got little or no snow, while the eastern Champlain Valley near the foothills of the Green Mountains got buried. 

The only bright spot to this episode is that Vermont ski areas got an unexpected but welcome dump of snow. 

WHAT WENT WRONG?

This was one of the most spectacularly wrongly forecast storm in Vermont I can remember in recent memory. And wrong with consequences. The expectation of  harmless, moderate cold rain, mixed with a little snow at mid and high elevations, turned into a dangerous winter storm. (At least in terms of power outages, tree damage and horrible road conditions).

The storm was an example of when temperatures are marginal, anything can happen. Forecasters believed temperatures would be just above freezing through most o the storm. The computer models, and meteorologists who examined them, suggested that a few inches of snow would fall on mountain summits. 

Also, areas at and above 1,500 feet would see one to three inches of snow before a likely changeover to rain.  Temperatures were expected to be around 34 degrees or even a tad higher through a thick layer of the atmosphere, from valleys to mountains and even above that. 

However, temperatures stayed just a couple degrees cooler than forecast.  Usually, if a meteorologist predicts an overnight low of 40 degrees and it turns out to be 38 instead, it's still regarded as an accurate forecast. 

But when a storm is ongoing, and the forecast is off by two degrees while readings are close to freezing, you can have real problems, as we did last night. 

Being a Monday morning quarterback, I can now see one clue ahead of the storm that might have let us know it was going to be a snowstorm, not a rain storm. 

In last evening's update, I noted predicted precipitation amounts would be a little higher than previously thought. It turns out that was a trend I'm sure many meteorologists wish they'd latched onto.    

t turns out precipitation rates and amounts were much heavier than forecast. When temperatures are marginal, as they were last night, heavier precipitation can cool the air a little, ensuring it lands on the ground as wet snow instead of rain

A for-example. Burlington was expected to receive the lighter amounts of rain compared to other parts of the state, maybe a third of an inch or so. Instead, rain, mixed with snow at times came down really hard at times, amounting to a storm total of 1.28 inches. A little more than half of that fell in just a two-hour period, which is an impressive precipitation rate for this time of year. 

 Elsewhere in Vermont, rain and melted snow was only a little more than forecast, but it might have been enough to help keep things mostly snow instead of mostly rain. 

Temperatures still remained near 32 or 33 degrees throughout the storm, which created a wet snow that was so destructive to trees and power lines.  And it made the snow that much more difficult to clear away. 

This whole episode is proof that although weather forecasting has gotten better in recent years and decades, we can sometimes really be taken by surprise. 

GOING FORWARD

Since weather forecasts around here are usually quite good, we're writing last night off as a bad moment. What happens next seems to be a little more straight forward.

The heavy precipitation has left Vermont, and we have scattered areas of light rain, snow and drizzle left behind. 

Temperatures in the 35 to 42 degree range late this morning and afternoon will help melt remaining slush on roads. However, temperatures will dip below freezing this evening and overnight. Remaining water on roads and driveways and such will freeze, making for some patchy slick spots tomorrow morning. 

Light snow showers will add to all that. Accumulations will be light, if they happen at all. But those snow showers might add to the overall annoyance. 

The next chance of any real snow or rain will come along Friday or Saturday, but it's too soon to tell whether that will be another nasty storm or just another nothing burger. 

a can't say whether