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| Tornado damage in Yarmouth, Massachusetts Tuesday. Photo by Steve Heaslip/Cape Cod Times |
Temperatures are pretty close to normal, and no big storms are in the offing that I can see. Elsewhere, it's wild.
That's all due to a jet stream in the Northern Hemisphere that's weird for July. It's what we call amplified, meaning northward bulges and southward plunges ain the jet stream are more pronounced than they normally are this time of year.
Which means we get extremes in weather. Some examples:
CAPE COD TORNADO
A rare tornado struck Cape Cod Tuesday as a supercell thunderstorm rampaged through. Again, that dip. A relatively sharp dip in the jet stream to the west of New England was one of many ingredients to cause this.
It looks like it was a high end EF-1 tornado, with winds estimated at 110 mph. I'm not sure, but I think the last tornado before this on Cape Cod was in 1977, so it's pretty rare.
The tornado and supercell had something called a tornado debris signature on radar, meaning radar was detecting debris blown aloft by the tornado. That enabled meteorologists to confirm the tornado via radar.
Strong rotation in the storm was detected off of Block Island, Rhode Island, well before it reached Cape Cod. That enabled the National Weather Service to issue timely warnings. Supercells usually have strong straight line winds, too, and this one was no exception. Winds in some places were clocked as high as 90 mph.
The roof of an inn was blown off in the tornado and there was massive tree damage. Dramatic videos of the tornado and supercell are at the bottom of this post.
SOUTHERN CHILL
July is normally a time of relentless heat and humidity across the South. But that dip in the jet stream to the west of New England I told you about is bring oddly low humidity to places south of the Mason-Dixon line.
When the air is relatively dry, nighttime temperatures usually get cooler than when the air is really humid. This rare burst of dry southern air is bringing some record low temperatures, which I'm sure nobody in the South is complaining about.
Cities in Kansas, Missouri, Texas, Arkansas, Oklahoma and elsewhere reported record lows this morning. Houston, Texas might get three consecutive mornings with lows in the 60s, which to us Vermonters doesn't seem chilly, but is frigid for a Houston July. They haven't had three consecutive 60s in July for at least 25 years.
EUROPE HEAT
Western Europe is in the throes of the second record breaking heat wave of the summer.
The worst of it in many areas is expected to peak Thursday, when the United Kingdom could break its all-time record high of 101 degrees. Paris, France, which endured some of the strongest effects of the June heat wave, when it set its all time national high temperature record, might do it again.
Paris is in line to break its all-time record high temperature as readings could get to 105 or 106 degrees there.
Record heat and the risk of wildfires exists not only in France but in Spain and Portugal. Record heat looks like it will also extend northward through Scandanavia.
Meanwhile, there's a dip in the jet stream to the east of these countries, so it will be unusually cool in parts of Russia and surrounding regions.
Still, the magnitude of the heat is greater than the extent of the cold, another possible sign of climate change.
CALIFORNIA HEAT
The west coast of the United States is heating up, too. Cities like Bakersfield, Modesto and Fresno could challenge all time heat records, with readings possibly exceeding 115 degrees in some areas.
Back to the Cape Cod tornado with videos:
Here's the roof of the motel blowing off in the tornadic winds:
A view out a window of the intense winds in or near the tornado:
Notice the wind change directions in this time lapse out of Dennis Port, Massachusetts. I'm guessing this was in the outer circulation of the tornado, and I think it was in the background in this video. Hard to tell, since there was so much rain:
Finally, a very nice analysis of what meteorologists were seeing on radar, from television station WCVB:
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