It’s the last Tuesday in July — just about the hottest day of the year over much of the northern hemisphere. But there is record-breaking cold weather in the central US, compliments of our old friend the polar vortex, normally dormant now but active this summer.
A tornado, a spinoff of the cold outbreak, struck a densely populated suburb of Boston yesterday, and lightning killed one and injured more than a dozen others on a California beach Sunday.
The tropical Pacific has been active for some time, and now the Atlantic appears ready to spawn its second named storm. There’s even news about the weather and hockey.
Let’s go around the world.
Cold Records Set In Central US
The persistent pattern of high pressure over the west coast and low pressure in the midwest that gave the eastern US such a brutal winter of 2013-14 has made its presence felt once again. Cold air plunging south brought record temperatures from Minneapolis to Memphis last night, and the cold air will push deep into Dixie tonight.
Residents who normally swelter under summer heat waves are now praising the polar vortex instead of cursing it. Refreshingly cool and dry air now covers most of the eastern US.
If the pattern holds through winter, the commentary will be different.
Tornado Touches Down In Suburban Boston Town
A rare Massachusetts tornado ploughed through a section of the Boston suburb of Revere, just seven miles from the center of The Hub. Miraculously, no one was badly injured by the 120 mile per hour winds, but homes, businesses, and vehicles were damaged or destroyed.
The storm formed on the turbulent edge of the cold air mass in the center of the country. Thunder and lightning -even hail — are common occurrences in eastern Massachusetts, but the conditions are not favorable for tornadoes. This one was rated EF2, and seemingly came out of nowhere, though there were thunderstorms in the area. Once in a while, atmospheric conditions unite to form something unexpected — and on the small scale of a tornado, they can do it quickly.
Not Exactly A Drought Breaker: California Gets A Thunderstorm; Lighting Kills One, Injures Many.
Los Angeles Airport recorded fourteen hundredths of an inch of rain on Sunday, the most ever for the date. It was only the twentieth July day on which it has rained in seventy years.
The thunderstorm produced a deadly lightning strike on Venice Beach, which recorded this year’s sixteenth death by lightning in the US. The average number for the last eight years is 33, and yearly totals have been steadily falling – possibly because of people’s awareness of the dangers of lightning, but there could be meteorological reasons.
When rain does occur at this time of year in southern California, it is from the monsoon that sprinkles Arizona with an average of about two and a half inches of rain for July. Occasionally a thunderstorm complex will make its way to the southern California coast.
The rain did nothing to alleviate California’s persistent drought, and climatologically the southern part of the state doesn’t begin to receive appreciable rain until well into the fall.
Tropical Activity Ramps Up Towards Yearly Peak
The Pacific Ocean has been active for some time, with a total of twenty named storms so far this year. And now it looks like the Atlantic, which has had only one, is ready to produce more tropical storms and hurricanes as the calendar turns the page to the peak months of August and September.
Western Pacific Ocean: After three powerful typhoons, the western Pacific is taking a breather. A disturbance southeast of Guam will become a typhoon, but spin harmlessly northward into icy waters.
Eastern Pacific Ocean: The string of storms incubating in the warm waters south and west of Mexico continues with what is now tropical Storm Hernan. Hernan was the third hurricane and ninth named storm of an active eastern Pacific season.
Atlantic Ocean: Following Hurricane Arthur’s early-July journey up the east coast, the Atlantic has been unusually quiet. Dry air and hostile wind shear has kept the lid on tropical cyclone formation. But the pattern has changed, and Bertha is in sight.
The dry air from the Sahara has retreated, and the Inter-Tropical Convergence Zone (ITCZ), where northeast and southeast trade winds converge, is now much more in evidence. One disturbance is in the center of the Atlantic Ocean and another is coming off the coast of Africa. We are entering the Cape Verde season, named for the islands off the African coast where tropical systems begin to spin.
The system in the center of the ocean, still 2,000 miles from the United States, appears to be ready to strengthen. The National Hurricane Center rates this system, ingloriously called Disturbance One, an 80% chance of becoming a tropical storm within five days. All forecast models bring it over the northern Caribbean islands and towards the US east coast. All interested in these areas should monitor this storm.
National Hockey League Warns Global Warming Threatens Sport
The National Hockey League, in its annual report, urges action on greenhouse gas emissions, lest there be no place left to skate. The league, and particularly the Toronto Maple Leafs, have put their actions where their articulations are: Green initiatives like cutting waste and donating unused food. It’s not the same as shutting down inefficient, carbon-belching, coal-fired power plants — but every little bit helps.
Weather Watchers Couldn’t Be Busier
The weather is fascinating all around the world. What’s it like where you are?
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