Brutal Cold To Ease Up, But Dry, Chilly Weather Continues; More Southern Tornado Drama

Bowed but unbroken? Daffodils once again sag after a brutally
cold, subfreezing night in St. Albans, Vermont but it still looks
like they have a shot at reviving when it warms up 

It looks like those Vermont daffodils have a shot of surviving after all.

Last night and this morning were certainly very cold for this time of year, but due to I think two factors, the chill didn't go quite as deep as it could have.

The core of the coldest air from Canada several thousand feet overhead was over northern New England during the day Wednesday. That's why, really amazingly for this time of year, temperatures never did get above freezing in much of the Northeast Kingdom, all day.

Although the air overhead remained incredibly chilly for late April, the coldest of the air had moved off to the northeast by late last night and this morning. That helped keep temperatures at the surface a wee bit milder than they would have.

More importantly, the wind kept going all night. It wasn't strong by any means. But to get the coldest possible temperatures on a clear night, you need light winds or no winds to get the best conditions to radiate heat to outer space.

That didn't happen last night. Temperatures did get into the upper teens in the coldest hollows, and most of us stayed in the 20s. Burlington, I think got down to 29 degrees. Montpelier was 25. Neither were record lows, and it was actually a tad warmer this morning than yesterday morning, which was the opposite of forecasts.

Many of the blooms outside our Vermont doors, because they're such early season specimens, will probably survive what we got last night.  Some things probably didn't make it, but overall, we will have spring after all.

Just not right away. Although it will turn "warmer" than yesterday - how could it possibly be any colder? -- temperatures will remain below normal into next week at least.

The good news is below normal ain't what it used to be.  Normal temperatures continue to rise fast this time of year.  Normal highs are in the mid 40s on April Fools Day and around 60 as the month ends.

Coming up over the next week, there will be a couple days here and there that get into the low and mid 50s. That's really not bad, but still a little on the cool side for late April.

HOW DRY I AM?

One thing I've noticed is, despite the rain showers and frequent unseasonable snows this month, it's a bit dry, particularly in northern Vermont. I noticed the gardens, when not frozen, are a bit dusty.

The dry conditions can raise the risk of brush fires this time of year. All that dead vegetation is dry out there. Sure, last year's leaves, weeds, twigs and such get wet whenever it rains or snows, but things dry out fast this time of year.

That's especially true in Aprils like this one in northern Vermont in which each precipitation event doesn't amount to much. It makes it easier to dry things out. It often get dry readily in Vermont anyway this time of year.   Here's why:

First of all, there's no leaves on the trees yet. That means the sun's heat can go down to the forest floor without being shaded by foliage. That allows things to dry out faster.

Also, when trees are leafed out, they add moisture to the air. There's no leaves yet.  If you make the air more humid, it makes it harder for fires to start and spread.

This time of year, pushes of air from Canada are particularly dry. These airmasses from the Great White North are cold, as we know from experience over the past couple of days.

The April sun is strong, though. That causes air pockets to warm and rise. Something has to replace that air that came up from near the surface, so really, really dry air from up above makes its way to the surface. These updrafts and downdrafts can create some erratic wind gusts, even when the overall weather pattern isn't that blustery.

Today will be a classic example. Temperatures will recover this afternoon well into the 40s.  That's still a good ten degrees cooler than normal, but it's better than yesterday, for sure. The air mass today is really dry, and will get drier as the afternoon sun mixes the air.

A great measure of how dry it is is by looking at the dewpoint temperature. Here's an example: If the actual air temperature is 45 degrees and the dew point is 25 degrees, that means it would have to cool down to 25 degrees to create fog or at least dew or frost on the grass.

The wider the spread between the actual temperature and the dew point, the drier the air is.  Today, a typical Vermont location will see afternoon temperatures of around 45 degrees with a dewpoint within a few degrees either side of zero.

That's super dry, and can easily create conditions to start brush fires. Luckily, we did have that bit of snow and rain yesterday and the day before, so that wetted things down just a little bit. Plus, although winds today might be erratic, they won't be particularly strong. That leaves us with some fire danger today, but not an extreme one.   The driest area seems to be the Champlain Valley.

So please, no outdoor burning today, or any other similarly dry days.  It can easily get out of hand and you don't want that.

It might turn a little wetter as we head into the weekend and next week, especially in southern Vermont, so that might help.

SOUTHERN TORNADO DRAMA

Screen shot of video by storm chaser Pecos Hank as a tornado rips through
the town of Madill, Oklahoma Wednesday.

More tornadoes ripped through the South again yesteraday and overnight.  Reports are that five people have died - three in Texas and two in Oklahoma.

A remarkable string of four tornadic supercell arranged themselves in a tight north to south line in southern Oklahoma during the afternoon and evening, producing some photogenic, but unfortunately destructive tornadoes.  

Click on this link to watch a very wild video by Pecos Hank as he sat pretty much in a tornado that rapidly developed in Madill, Oklahoma. You'll see it wrecking a steel wire plant there. The tornado then moves on, leaving wreckage and a beautiful, sunny late afternoon. (It was even sunny from Pecos Hank's position watching the tornado. Go figure.

An even more remarkable tornadic supercell formed near Austin, Texas and traveled nearly 450 miles to the Louisiana-Mississippi border Wednesday afternoon and evening. That is an incredibly long lasting, durable supercell, especially considering it kept dropping tornadoes along the way.

The worst one was in Unalaska, well north of Houston, where the supercell dropped a powerful tornado that led to three deaths and widespread destruction in town, according to television station KPRC in Houston.

Severe thunderstorms and possible tornadoes continued overnight and into this morning in parts of Mississippi and Alabama.

Another round of storms and possible tornadoes are in the forecast for later today, especially in the southern halves of Alabama and Georgia.