Shower Chances, Maybe Strong South, Tropics Turning Active

Hanging baskets looking to the clouds and waiting for rain recently
on my back deck in St. Albans, Vermont. Flower and structural
design by my husband, Jeff Modereger

It's still not nearly as wet as I'd like it to be here in Vermont as the trend in below normal rainfall has continued since it at least April.

There are chances for showers and storms off and on through next week.  But I don't see anything major at this point. It also appears  - for now, anyway - that the imaginary anti-rain force in the Champlain Valley is holding strong.

Shower and storm chances look best for the next couple of days outside the Champlain Valley, though we can hold out some hope a stray shower will hit there, too.

There's actually a chance of strong to severe storms today in far southern Vermont and points south of there through southwestern New England down into the Middle Atlantic states.  High winds are the biggest threat in this broad area of severe storm risk, though an isolated, brief tornado can't be ruled out.

Further north, there might be a rumble or two of thunder, but nothing huge. Already this morning, a narrow band of showers has dampened a good chunk of southern Vermont, but that was moving out.

By later today and this evening, there will be a good shot at some showers outside the Champlain Valley.  In the valley, there will probably be some patches of rain, but the chances are there are a little less than elsewhere in the state, at least in my opinion.

It looks like more showers and storms will form tomorrow, but again, the best coverage seems like it could be outside the Champlain Valley.  It's not that northwestern Vermont will miss out on the rain. That area will almost certainly get some.  Just not as much as points south and east.

NOAA's Storm Prediction Center has all of Vermont of most of the Northeast in a marginal risk zone for severe storms on Thursday. That means there might be isolated incidents of strong, damagiing wind gusts, but nothing widespread.

The next real chance of rain in Vermont after tomorrow will come along on Sunday.  No guarantees on how much that will amount to, but all the meteorologists will surely keep an eye on that.

TROPICAL TROUBLE

Hurricane experts have ramped up the alarm bells about this year's hurricane season potential, given the unusually warm waters in much of the Atlantic Ocean where hurricanes tend to form. Other atmospheric factors still favor a lot of storms. Even worse, the current weather pattern, it it holds, would tend to steer storms toward the United States.

Summertime clouds not quite getting their act together enough
to produce showers this past Monday over St. Albans, Vermont.

We've already had hints of a troublesome year, since we're way ahead of normal in terms of how many tropical storms have already formed. There's already been six, but thankfully, they've all tended to be pretty weak.

Stronger hurricanes tend to get going in August and September, and you should expect the tropics to start becoming more active right about now.

The tropics certainly got that memo. Probably by the time you read this, Tropical Storm Gonzalo will have formed way out in the central Atlantic.  From there it will move west toward the Caribbean Sea, but exactly where and at what strength is anybody's guess

Wannabe Gonzalo is a tiny, cute little thing spinning out there.  Tropical systems that are small in size are notoriously hard to forecast, both in terms of strength and direction.  When such a storm is tiny, just a little bit of dry air intruding or a few gusts of strong upper level winds can tear it apart and kill it.

On the other hand, a tiny storm can defy predictions and cloak itself in its own protective shield of moisture, and strengthen quickly.   Right now the National Hurricane Center is taking, in my opinion, a correct conservative approach and just maintaining Wannabe Gonzalo as a tropical storm right through the weekend.  They'll surely change and update this forecast in the coming days.

It's possible Wannabe Gonzalo could pose a United States threat next week, but that is a big question mark right now.

Another weaker tropical type system is lurking in the Gulf of Mexico.  It's unlikely to become a tropical storm, though some computer models think it will strengthen to that level.  It's headed toward Texas, and will give parts of that state a deep soaking this coming weekend.

Another batch of storms that will move off the west coast of Africa in the next few days will also have to be watched in case it turns into an eventual threat.

More Vermont 90s, And Interesting Hot Green Mountain State Trends

Burlington managed to eek out another day above 90 degrees on Monday, making it the 15th day this year already in which it has gotten to the 90 degree mark.

A so-called cold front had passed through earlier in the day, but the slightly cooler air lagged far back in Ontario, so it wasn't really until evening that we began to feel some refreshing breezes from the northwest.

Ben Frechette, a meteorologist at WPTZ-TV, loves looking at data, as I do, shared some more stats yesterday.

I've been saying all along that the average number of days that get to 90 degrees in Burlington each year is five.

That's true if you look at the data starting in the 1880s and going through until now.  However, many climatologists look at the average going back the past 30 years or so.  If you do that, the average number of 90 days in Burlington is eight.

Frechette shared the chart you see in this post.  (Click on it to make it bigger and easier to see).

The chart shows the yearly number of 90 degree days in Burlington dating back to 1883. The darker line you see in the chart is the 30 year rolling average for the entire data set.

As you can, there is a definite trend toward increasing numbers. Such a long term trend suggests to me that climate change is playing a role, but it's probably not the only thing going on.

There are probably some cycles thrown in amid the general climate change warming. You can clearly see a spike in the number of 90 degree days in the 1940s.

Part of that might be because there was less forest in Vermont back then than there is now.  If you have more forests, you tend to have cooler temperatures in the summer because of all the transpiration and water evaporation from the trees.

But there was about the same or even even less forest cover in the decades before the 1940s, and no corresponding higher number of 90 degree days.  For whatever reason, though, the 1940s were generally warmer and drier than previous decades.

Vermont had as little as 20 percent forest cover in the late 1800s due to farmers clearing the land. By the 1980s, forest cover had reached about 75 percent.  It has stayed relatively steady since.

Moreover, rainfall has increased in Vermont during the past few decades, at a rate of about 1.5 inches per decade since 1960 or so.

Scientists think climate change is largely behind the increased rainfall. Remember, all that water from the trees and those rain storms might make it feel more humid in the summer, but the moisture also works to keep the temperatures from spiking.

That's because in wet times, more of the sun's energy goes toward evaporating water than heating the air. Plus, excess moisture can at times create extra clouds, blocking the sun, though that's not always the case.

You'd think the increasing forests and the heavier rainfall would work against an increasing trend of summertime 90 degree weather. But you see the rising trend in Frechette's chart.

One big caveat:  The immediate Burlington area has seen more suburbanization and sprawl over the past four decades than most other parts of Vermont.  The National Weather Service in South Burlington makes sure to calibrate things to ensure accurate temperature readings.

Still, I don't see as much of a warming trend in areas of Vermont that haven't changed as much as the Champlain Valley has. This part of the Champlain Valley has probably lost of bit of forest cover since 1970 or so.

I admit I have not deeply analyzed data from places like Montpelier or St Johnsbury, but I suspect the rising temperature trend lines in those communities might be a bit more tempered.

Maybe Frechette can look at that, although the dude is already incredibly busy with his weather duties at WPTZ.

Not 100 Degrees, Here's Why (But Still Plenty Hot!)

It's still hot, so I'll try again to cool you off with a winter
photo of my St. Albans, Vermont driveway. 

Burlington, Vermont fell well short of the speculated 100 degree reading many of us were contemplating on Sunday.

Things have to line up just perfectly to reach the triple digits during Burlington heat waves and they assuredly did NOT line up correctly on Sunday.

It's only gotten to 100 degrees four times in the past 150 years or so in Burlington, so it's a pretty high bar to cross.

If the atmosphere is hot enough for 100 degrees, you're not actually going to get there in  Vermont unless you have full sunshine.  We didn't have that on Sunday

The writing almost seemed on the wall by early to mid morning Sunday.   A dying complex of shower and storms up in Quebec sent some clouds across the northern half of Vermont that didn't clear out unti mid-mid morning.

That delayed the days warming and put us behind schedule to reach that magic triple digit figure.

We had a few hours of full sunshine that brought temperatures up above 90 by shortly after noon.  However, a powerful line of thunderstorms in southern Ontario had blossomed and blew a veil of high, thin clouds our way, starting in the early afternoon.

The clouds dimmed the sun, preventing it from fully heating us.  Burlington "only" reached 95 degrees. It wasn't even quite the hottest day this summer, but it was pretty damn hot by anyone's standard

Burlington fell short of the record high for the date, which was 98 degrees. However, St. Johnsbury broke their record high, reaching 95 degrees besting the town's old record for the date of 93.  Montpelier tied its record high of 91, and Springfield in Vermont's southeast tied its record high of 92.

RAIN MOSTLY MISSES, AGAIN

It was interesting to see the Champlain Valley's 2020 anti-rain force field in action yesterday. That powerful line of storms in Ontario basically went "poof" on its way here.  In the tragic remnants of that line of storms, a new batch of storms formed in northwestern New York, prompting severe thunderstorm warnings in the Adirondacks.

That line fell apart on the way to the Champlain Valley so we only got light showers. More storms then redeveloped east of the Champlain Valley.

A small local downpour did go over my house early this morning.  I guess the anti-rain force field was taking a pre-dawn nap. Between light showers last evening and a 4 a.m. - ish  downpour, I collected a respectable 0.7 inches of rain in St. Albans.  Burlington could only muster 0.07 inches.

STILL A HOT SUMMER

We've got one more hot one to go today.  A cold front has gone through, but you wouldn't know it.  It's still hot and muggy.  There's a slight chance Burlington could reach 90 degrees again today, but it most likely will be well into the 80s instead.

Somewhat cooler, but still warmish weather will continue the rest of the week.

So far this summer in Burlington, it's gotten to at least 95 degrees six times.  The record for the most such days is nine, in 1944 followed by eight in 2018.

Burlington has had 14 days in which it got to 90 or better so far this year, The most in a single year is 26.

Sunday was the 24th consecutive day in which the temperature failed to drop below 60 degrees in Burlington. The record is 30 such days in 1988.  I don't think we'll break that record because I suspect we might have a couple days this week in which it'll go into the upper 50s at night.

For what they're worth, the long range forecasts don't really promise us any strong Canadian cold fronts anytime soon. The 8 to 14 day outlook calls for continued generally warmer than average weather for us into the first days of August.

Will Vermont See A Rare 100 Degree Day Today?

Will it get to 100 degrees today in Burlington, Vermont?

As we said yesterday, today is going to be terribly hot across Vermont and surrounding areas.  Pretty much everybody will be in the 90s, and the whole state is under a heat advisory, except the extreme northeast corner of the state.

The speculation has started on this one: Will Burlington, Vermont reach a rare 100 degrees today?

It's only been 100 degrees in Burlington four times since they started keeping track of this stuff in the late 1800s.

Those times were:

100 degrees, July 3, 1911
101 degrees, August 11,1944
100 degrees June 19, 1995
100 degrees July 14, 1995.

Will today join this list?

The National Weather Service in South Burlington decided to pull the trigger and predict a high of 100 degrees today.  However, meteorologists at the NWS office note that some factors might prevent us from getting that hot.

It might "only" get to between 97 and 99 degrees.

Following are the factors that would encourage a reading of 100 degrees and factors that argue against it.

FOR 100 DEGREES

Computer forecast models that show a good layer of the atmosphere can support such temperatures down here near the ground.

Southwest winds that can compress the air coming down the slopes of the Adirondacks, thereby heating the air more than it would otherwise.

The air will mix well in the lower several thousand feet of the atmosphere. That would bring the humidity down a bit.  If the humidity is lower, then it can get hotter.

There should be a lot of sun this afternoon, which obviously encourages heating.

It's been dry.  Wet ground adds humidity to the air, and as noted, actual temperatures have a harder time reaching their maximum temperature with higher humidity.  All four cases in which it was 100 degrees in Burlington came during dry periods, like the one we're in.

AGAINST 100 DEGREES

Forecast models this morning indicate the airmass will be marginally cooler than forecasts issued yesterday, but by all means remain hot.

A dying mass of showers and thunderstorms in southern Quebec early this morning was keeping clouds across northern Vermont.   If clearing is delayed later this morning, it could prevent temperatures today from maxing out at their highest potential.

Will the southwest winds pick up just enough influence from Lake Champlain to cool things to just below 100 degrees?

It's also simply damn hard for temperatures to get to 100 degrees. Everything has to come together perfectly.  A few rogue fair weather cumulus clouds in the afternoon could easily kill chances of it getting to 100 degrees.

BEYOND TODAY

There are encouraging signs that it might stay as warm for the next week or so as initially thought.  There's going to be an ahhhhh factor here and there over the coming days.

Tonight will humid and stuffy as hell ahead of an oncoming cold front. To make sleeping more difficult, this cold front is likely to bring some scattered showers and storms overnight, especially north and west.

Storms ahead of this cold front will likely be severe this afternoon and evening across southern Ontario and western New York, but will weaken as they move into Vermont.

The actual cooler air lags well behind the cold front, so Monday will still be very warm and kind of humid, with temperatures in the 80s to possibly near 90.

Then we get into the better weather.  Dew points, a measure of how comfortably or uncomfortably humid it is out there, are expected to drop into the low 50s Tuesday.

That's the lowest they've been in weeks and definitely in the comfortable zone.

It'll probably turn vaguely humid midweek but nothing extraordinary.  The core of the nation's heat will be centered further west for awhile, temperatures will probably stay pretty close to normal for the next week or so after today's heat.

Sunday's Squirt Of Hot Air Will Be Nasty

The middle of the nation is still broiling under a relentless heat wave, and a squirt of that very hot air looks like it will make it to Vermont on Sunday.    

The color shading on this map has most of New England outside of
Maine in the 95-100 degree range Sunday afternoon. Click on
the image to make it bigger and easier to see.  If you look
closely, this particular map has a foreast high of 99 degrees
in Burlington, Vermont. We shall see. 

The good news is the hot air will be flushed out by a cold front by Monday, though it won't exactly be "cold" behind said weather front. 

Temperatures here will remain above normal, but  not torrid, like the kind of weather expected in parts of the Plains and South, and below the Mason-Dixon Line along the East Coast.  

A warm front passed through yesterday, with disappointingly light showers in the morning.  We had a gorgeous evening, though, but the warm to hot air is now being established.  Today will be definitely on the warm side, with highs well into the 80s, with a few spot 90 degree readings in the warmer valleys.

Tonight, especially in the Champlain Valley where a south wind will prevent radiational cooling, it will be on the stuffy side.  I imagine the "low" temperature in Burlington tomorrow morning will be around 75 degrees or so.

All the ingredients are coming together for a very hot Sunday. Temperatures through a thick layer of the atmosphere will be at near record high values. 

For the Champlain Valley, the wind will be coming out of the southwest.  It'll come down the slope of the Adirondacks in that scenario.  Air flowing down the slopes of a mountain gets compressed, which heats it.  

As usual, the air column over us does get cooler with height.  But at around 8,000 feet overhead, says the National Weather Service there will be another layer of warm air which would prevent any cooling thunderstorms to develop on Sunday. 

If you want to cool off, here's a photo of cars stuck on the hill near
my St. Albans, Vermont house during a March, 2017 blizzard

Taken together, all this means an we should endure an expected high in the mid to upper 90s in the Champlain Valley on Sunday and highs of 88 to 95 in pretty much the rest of Vermont. 

One or two models or forecasts I've seen predict a high of 100 degrees in Burlington Sunday. I suppose that's possible, but I see it as pretty unlikely. 

To nobody's surprise, a big chunk of Vermont and surrounding areas is under a heat advisory on Sunday, so take it easy!  Do your outdoor work very early in the morning, and retreat to air conditioning if possible by afternoon.  Have your nice drinks of water or other refreshing non-alcoholic beverage handy, too.

I'm saying non-alcoholic, not because I'm on some sort of temperance movement. It's just that alcohol can exascerbate the effects of heat. 

The only saving grace regarding the heat tomorrow is that the air will mix in the lowest several thousand feet of the atmosphere. That will tend to lower the humidity just a bit for a time in the afternoon. And most of us will have a steady breeze, instead of having to endure still, hot air 

The record high in Burlington Sunday is 98 degrees set in 2013.  That's a pretty high record, so it will be tough to beat. Montpelier's record high for the date on Sunday is 92 degrees, so that one is in jeopardy. St. Johnsbury's record high is 95 degrees, so we'll see about that. 

That cold front is coming through later Sunday night or early Monday.  The timing is such that we probably won't see any severe thunderstorms with it.  Any rain that does fall Sunday night or early Monday will unfortunately be only scattered a brief.

A few spots might get a decent dousing from some embedded downpours, but this won't be any kind of widespread rain. 

Behind the cold front, it will be dry and only a little warmer than average for the first half of the week. Other weather disturbances give us a risk of some showers later in the week but temperatures will still remain mostly in the low 80s for highs.  So that's not terrible. 

The Monthly Global Assessment: Surprise! Hot Again

As we do every month, we check in with NOAA's Centers For Environmental Information to get the regular update as they check the world's temperature.

As always, the Globe is running a fever.

June, 2020 was the worlds third hottest on record.

I suppose if you're looking for a bright side, at least June wasn't #1 or #2  on the heat scale like most months in the past year.

Overall, the places with the warmest temperatures, relative to average were most of the United States, southern Brazil, northern and eastern Europe, northern Russia, southern China and the North Pacific Ocean.

Even in a warming world, there are always places that trend cooler in a particular month. This time, those places were western and southeastern Russia, India, Greenland and parts of the North Atlantic Ocean.

It was good that Greenland was cool at the time of year when the sun angle is highest in the northern hemisphere. It probably cut down on the amount of melting Greenland has been seeing in recent years.

Of course, other parts of the Arctic were much warmer than average.

As of July 15, Arctic sea ice extent was the lowest on record for this time of year, beating the record low last set in 2011, according to the National Snow and Ice Data Center.

The sea ice is particularly pathetic north of Siberia, which has had months of far above normal temperatures this year.

IN VERMONT

Locally, as we know, it's been a hot summer so far in Vermont. We have another squirt of very hot weather coming up, but luckily, this one won't last super long.

You'll notice the humidity building today as showers taper off. (The showers, as I expected, were more lame than many forecasts).  Northwest Vermont in particular seems to have an anti-rain force field this summer.

Saturday will be humid and relatively  hot, with 90 readings likely in the warmer valleys.

I'm sure there will be some heat advisories Sunday as the humidity builds more and temperatures go well into the 90s.  Burlington at this point is expected to get up to 97 degrees Sunday, which would make it the hottest day of the year if it comes to pass.

Luckily,  cold front will come to the rescue late Sunday night and Monday. After the front passes, it won't exactly be cold, but temperatures next week look as if they'll be near, or just a little warmer than average.

If the cold front is later than expected, we might squeeze one more 90 degree afternoon Monday, but after that, I'm guessing no more 90-degree weather for the rest of next week.

Nationwide Heat Is Certainly Persistent

And the heat goes on.  Most of the nation, including Vermont
can expect above normal temperatures through the
end of July. 

It's been a hot month for pretty much all but the northwestern corner of the continental United States as no real cold fronts or pockets of cooler air have interrupted the long, drawn out heat in the troubled summer of 2020.

The length of time the heat has settled over us, and the broad area it has covered is the impressive part. There haven't been many all time record hot tempertures, but the torrid weather has just dragged on.

Washington DC's longest stretch of consecutive days at 90 degrees or hotter is 21, set in 1980 and 1988.  As of today, they're up to 20 consecutive days this year.  The forecast high in DC today is 90 degrees. Tomorrow, it's forecast to reach 94 degrees.

Miami, Florida, just endured 20 days with a daily heat index reaching at least 103 degrees.  There have been 23 days this year with a high temperature of at least 94 degrees in Miami, the most for any entire year on record. And it's only mid-July, so there's more coming.

Buffalo, New York,  endured 90 degree temperatures daily from July 3 through 10, peaking at 98 degrees. Those eight days were the longest streak of 90 degree weather on record.

An exception to the lack of all time record highs rule this summer is Texas.  San Antonio, Texas on Monday had its hottest July day on record when it reached 107 degrees. Amarillo, Texas set a record for the month of July and suffered its second hottest day in that city's history with a reading of 110 degrees. Del Rio, Texas tied its July record of 112 the same day.

In Death Valley, California, the low and high temperature there Sunday were 100 degrees and 128 degrees. Yes, it's always torrid in Death Valley during the summer, but that 128 degrees is the hottest any place in the world has seen for at least two years.

The Pacific Northwest is the one "air conditioned" spot in the U.S. this summer. For instance, all but three of the first 15 days of July in Spokane, Washington were a little cooler than average.

Here in Vermont, the warmth has been persistent, too. Especially at night.  Burlington is having one of the longest periods on record in which the temperature has stayed at 60 degrees or above.  So far, we're up to 20 consecutive days.  The longest such stretch was 30 days in July and August, 1988.

Only one day so far this month has failed to reach 80 degrees. It was "only" 79 degrees on Tuesday.

Those looking for a break in the warmth, heat and humdity are out of luck. We in Vermont enjoyed a taste of slightly lower humidity the past couple of days, but that's coming back, starting tomorrow.

A warm front will at least hopefully bring a round of showers tomorrow morning. By Saturday and Sunday, we will probably be closing in on 90 degrees again, with increasing humidity.

It will cool down slightly again next week, but it will be far from chilly, with daily highs still likely to exceed 80 degrees, with no big pushes of cool, dry air from Canada expected. The overall pattern features generally warmer than normal weather here in the Northeast through the end of the month.