The atmosphere must be pulling no punches, for where the computer models tend to disagree once you get more than five days into the future, they all agreed. A hot pattern was building.
Over on his blog on the Weatherbelle site Joe D’leo went so far as to look ahead to this coming Friday and say we might call it “Fryday”. This coming Friday is June 21, and he was writing on June 13, and that involves enough time to make such a forecast very risky. However certainty was surprisingly high among the weather guru’s. I’m not sure why.
The upper air winds were changing. Stealing from Joe’s site, the forecast was for an upper air “trof”, bringing us refreshing air from Canada….
….to be replaced be replaced by a ridge of great magnitude.
If one looks, it becomes apparent that the high pressure in the second map is no longer a wave in the west-to-east flow of upper air winds, but rather its isobars describe a complete circle. The high pressure has become an entity separate from the west-to-east flow, in some ways like a low pressure when it is occluded and becomes a “cut off low.” But, rather than call it a “cut off high” it is often called a “heat dome.”
I keep running into the subject of heat domes, as I meander through my thoughts. For example, I know that a tremendous heat dome developed during the murderously hot summer of 1936, during the Dust Bowl. But I knew nothing about the dynamics. To learn more, I thought I would conduct a quick web-search.
Yikes! Did I ever open a can of worms! I ran headlong into the balderdash of the Global Warming fruitcakes, making such a confusion I knew that a “quick web-search” would be impossible. I’d have to carefully screen the data to remove dross from the gold. And that would take time.
I didn’t happen to have the time. Hopefully I’ll find time soon, for there is much about “heat domes” that seems fascinating, and I’d like to better understand.
For one thing, they perpetuate themselves when it seems to me they should be self destructive. Hot air should rise, creating low pressure at the surface, and thunderstorms above, but this doesn’t happen. The high pressure up at 500 mb presses down, suppressing updrafts and clouds, and making the summer sun beat down on the surface and overheat it, and over-dry it, which makes for even less clouds. However what I don’t get is how this translates upwards and refuels the upper air high.
The weather doesn’t care if I get it or not. It knows I will get it when I get hit by it. And today we got hit by day one.
Yesterday was a sort of transitional day, with the dewpoints low, around 56, at sunrise, yet rising to 65 by sunset. In layman’s terms, you could feel the air shift from refreshing to muggy. However temperatures didn’t spike, for the onrushing warmth created a very dry warm front, with only a few high clouds and dots of low cumulus, but noticeable because, ahead of this basically invisible front, winds were southeast and therefore off the cooler Atlantic. This brought air more moist than Canada’s, but held temperatures in the seventies. Then, around sunset, the power of the sea-breezes faded, and the invisible front pressed north, and winds became southwest. To a layman this means, in the evening twilight, you can smell a change in the weather, for the night feels warm and the air more like Carolina’s than Canada’s.
This morning made it obvious we were in for the real deal. The first sunbeams felt hot, and both dewpoints and temperatures soared, above seventy and ninety respectively by eleven in the morning.
But then some scattered cumulus arose, which doesn’t happen if you are truly under a “heat dome”. And each time one of these little clouds crossed the sun a blessed coolness was felt. I could measure it, for my sons gave me a birthday present of a modern “weather station”, and it measures every quirk of temperature. One little cumulus lowered the temperature from 91.1 to 87.7. Of course, as soon as that cloud passed temperatures rebounded to over 90, but it showed we were not “under the dome”, but rather towards its periphery. Around the dome is a “ring of fire” made of showers and thunderstorms, and usually that is where we lie.
The fact of the matter is that, while we may have a “hot spell” in our hills, we almost never have a “heat wave”. To be an official heat wave you have to have three straight days with temperatures over ninety.
I’ll believe it when I see it. But we have made it through day one.
Sunrise's Swansong 
Its a long way from New Ipswich to Fredericsburg. But, the same atmosphere makes the connection above and the same earth connects them below. Our arm of the Atlantic, Mexico’s Gulf runs a bit warmer than its Mother body, but it still sends an arm streaming up that way to make another connection. Canada’s airs even get shared, though rather less and even less so in the Summer season. While the drying “Heat Dome” settles in for those Northern reaches with the “horrors” ninty degree F days, I recall its laying a blanket in other days and summers over Fredericksburg temperatures of ten degrees and more higher.
Both of us have shared somewhat our respective climes at least a little. Travel offers a lot of insight into other possibilities of perception. My excursion into Alaska once hardly counts for representing anything of New Ipswich. But a couple of rides into West Central Wisconsin a couple of days on the south shore of Lake Superior comes closer. On that occasion I arrived in Lacrosse to find that Fredericksburg is not unique in offering 100+ weather in July. But, it was revealing to move a couple of days later to have Canada show us its stuff by dropping its twenty degree cooler air on us.
Thus refreshed my wife and enjoyed a ride to the southern shores of Lake Superior to enjoy its citizens and climate. Of citizenship there were Black Flies whose attentions were as welcome as the Horse Flies experienced at poolside once upon a time in Arkansas. It was a National Forest setting on the Lake where we were setting up camp for our overnight rest and I assured my wife that darkness would see the end of that torment. I had not counted on the night crew of mosquitoes.
My bravado of prediction was based on experience. I had once assured some folks living in a forest environment that their mosquito problem would disappear in about an hour. It proved accurate. I was visiting these folks as a part of my job duties. I knew my local mosquitoes and recognized that the afflicting species, an only day active woodland variety, would pack up at sunset. And they obligingly did.
I was theoretically aware that differing environments offered their own particular faces and required experience to appreciate. But, this was a realization in real time in which the experience that is required to drive the knowledge home in a way that theory never can did its job.
We broke camp the next morning to actually see the lake shore and found on a July day that our new day was closer to a South Central Texas winter day than the expected heat of summer. Very windy blasts carried sixty degree air across the lake against our face and the rest of us most uncomfortably in our summer attire.
So much of perception is bogged down in what is relative. My son in law some years back was in Pennsylvania doing his Civil War reenactment hobby. While some among the Yankee cohort was reporting near heat prostration under the mid to high 80’s, the Confederate Texas contingent was enjoying the moderation of what temperatures they would have back home.
So, our aged New Hampshireite Is going to see some warm days concurrenbtly and I’ll be seeing a – – – I’m not sure. Our geographical spot sits on what seems to me a cusp between. Between dry and wet, though mostly dry. Between cold and warm, sometimes hot.- as hot as 115 or so and as cold as single digits. Nothing like Death Valley or New Ipswich, but sometimes reminiscent of either.
At my first opportunity to explore a college library in the mid 1950’s I stumbled onto little book reviewing weather patterns as recorded when the book was written sometime before 1940. In it were a few maps showing patterns of weather experienced across large areas of the United States over time. On reflection what I saw was as though looking at a trampoline from below. There was a sequential pattern of large scale isographic lines showing drought-wetness, cool-warmth etc, as though some giant was dancing and jumping thereupon. In the some sixty years since there has been real change in the insight those pages offered with their limitations of data then available. The trampoline still shows the continuing mesmerizing dance.
Caleb, you aren’t the only one who wanders word space with a measured dose of loose, seeming carelessness. And bless the typos,; they keep us humble and forgiving of orthographic sin.