Wild Differences In Vermont Weather Saturday; Big Changes Coming Statewide

There's that achingly tired old saying that if you don't like the weather in Vermont, wait five minutes, it'll change. 

Saturday in St. Albans, Vermont, some irises enjoy some
warm evening sun.....

On Saturday, the phrase should have been, "If you don't like the weather in Vermont, drive a short distance, it will change." 

There was indeed quite a contrast in weather across the Green Mountain State. Here where I am in the northwestern corner of the state, it was an absolutely lovely late spring Saturday. 

Skies were blue, there was a pleasant breeze, and temperatures got into the upper 60s, just a wee bit cooler than normal for this time of year. 

Drive to southern Vermont, go up in elevation far enough and you hit snow.  Atop Stratton Mountain, it snowed most of the day.  Snowflakes mixed with rain Saturday morning at elevations as low as 2,500 feet.

Many towns in southern Vermont never made it out of the 40s for highs Saturday afternoon.

The reasons behind Saturday's contrast were pretty unusual. 

very once in awhile, you'll have temperatures and weather differences in Vermont this extreme if there's a sharp warm, cold or stationary front somewhere in the state. 

This usually happens in the colder half of the year, when a weather front bisecting the state would give winter conditions to, say St. Albans, while it's 60 degrees or more in, say Bennington.

...while atop Stratton Mountain in southern Vermont, a nice
winter sunset was underway on (checks notes) May 29.
This is a screen shot from the Stratton Mountain web cam

What made Saturday's contrast in Vermont so odd was there were no weather fronts. The strong sun, near its peak intensity this time of year, made all the difference. Making Saturday quite a unique weather day in Vermont.  

In the far north of Vermont, strong, cool high pressure up in Quebec fed very dry air into those parts of the state. That meant plenty of sunshine to heat the atmosphere. 

 The air was also super dry for May. Dew points, a measure of how wet the air is, were only in the upper teens in far northwestern  Vermont.  That's exceptionally low for this time of year. 

he sun can heat dry air much more efficiently that humid air, so temperatures went up nicely in the afternoon. 

In the south, the state was locked under thick clouds.  That cool air from Canada made it into all of New England, but wet air from an upper level storm and a particularly cool pocket of air aloft kept things frigid. The thick clouds blocked the sun, so it stayed nippy.  

Clouds made all the difference in Saturday's weather
The northwestern tip of Vermont was in the sunshine,
will thick clouds socked in the south. 

The Vermont contrasts will even out today and tomorrow.  The northwest will still be a little warmer than the south today, as the day up north is starting with some sun. But that upper level low is re-orienting itself, and will send clouds and rain statewide later today and tonight. 

Everybody will be cool today, with highs in the 50s, with a few low 60s far northwest. 

The cool pool of air aloft is slowly modifying, so I don't expect any more snow. Maybe an outside chance of flakes at summit level, but that's it.  

It'll be chilly tomorrow, too, under lingering clouds and showers. 

More than an inch of beneficial rains are coming to the southeastern half of the state.  The northwest is in desperate need of rain, but those areas won't bet much.  Maybe a third of an inch or even less, especially north and west of a Burlington to Jay Peak line. 

There are signs that we are in for another type of big contrast:  The overall weather statewide might go from a March-like nip to full on summer. 

The ever famous summer feature, the Bermuda High off the East Coast looks like it really wants to strengthen and poke firmly west into the eastern United States.

If forecast holds, we could go from snow in the southern Green Mountains yesterday to oppressive heat and humidity by next weekend.  We'll keep an eye on that.