ASK TOM: What is an “embedded thunderstorm”?

Dear Tom,

What is an “embedded thunderstorm”?

– June Wheeler,  Madison, Wis.

Dear June,

Webster’s New World Dictionary defines “embed” this way: “To set or fix firmly in a surrounding mass.” The precipitation that falls with major storm systems often extends across areas as large as several Midwestern states. Meteorologists refer to these as “synoptic scale” events. This kind of precipitation distribution differs from the relatively narrow bands or isolated clusters of showers and thunderstorms that usually occur in the warm season.

When In a situation in which a large precipitation area includes scattered thunderstorms, those storms are said to be “embedded” within the larger precipitation area. A forecast of rain and embedded thunderstorms suggests an extended period of rain that might occasionally include a thunderstorm.

ASK TOM WHY: How windy was it for the May 17, 1979 Cubs game at Wrigley Field?

Dear Tom,

How windy was it for the May 17, 1979 Cubs game at Wrigley Field when the Phillies beat the Cubs 23-22?

Allen Moody
Island Lake

Dear Allen,

There have been windier days at Wrigley Field, but the wind was definitely blowing out on the afternoon of May 17, 1979. According to Chicago weather historian Frank Wachowski, south winds were blowing straight out to left field at 20 mph with gusts in excess of 30 mph during the game. There were 11 home runs hit that day, including three by Cubs’ slugger Dave Kingman and two by Mike Schmidt of the Phillies. After one inning the Phillies led 7-6 and the Cubs overcame as 12-run deficit to tie the game in the 8th, only to lose it in the 10th on Schmidt’s second homer,

ASK TOM: Advice for those who fear thunder

Dear Tom,

My 5-year-old, Jenny, is mildly afraid of thunder and lightning. Do you have any advice for her?

— Jim Sumner, Schaumburg

Dear Jenny,

You’re not alone in being frightened of thunderstorms. Many grown-ups find them to be scary. But because they are older and have witnessed many storms, they know how to stay safe. Thunderstorms have always been around, and they aren’t all bad. They lower temperatures on very hot days, and they bring needed water to our ponds and lakes and our thirsty lawns and farm plants. Thunderstorm rain cleans pollution out of the air. Lightning even makes fertilizer from nitrogen in the air, and that fertilizer falls with rain. It is important to know that most storms are not damaging, and you will be safe if you go indoors. Warnings are issued for dangerous storms.

ASK TOM WHY: Has a record high and low temperature ever been set on the same day one year apart?

Dear Tom,

Has a record high and low temperature ever been set on the same day one year apart?

Steven Pacific

Dear Steven,
It has occurred several times, but none more dramatic than the periods leading up to Christmas in 1982 and 1983. Driven by a strong El Nino, Chicago established balmy record highs of 62 degrees on December 23 and 64 degrees on Christmas Day in 1982. The next year with a persistent Siberian Express in control, record lows of minus 21 and minus 17 were logged respectively on the same dates. Other occurrences of year-apart record highs and lows- April 21 1985- 88 degrees -1986 27 degrees, May 11, 1982-89 degrees 1981-33 degrees, July 28, 1983-100 degrees, 1984-51 degrees, and October 21, 1953-87 degrees, 1952-26 degrees.

ASK TOM: Guidelines for suspending outdoor activities when lightning and t-storms threaten

Dear Tom,

What are the guidelines for suspending outdoor activities like baseball when lightning and thunderstorms threaten?

— Andrew Reinhardt


Dear Andrew,

All safety experts say outdoor activities should cease immediately when thunder is heard. Thunder is a byproduct of lightning, so if thunder is heard, lighting is present. This might not be apparent in daytime thunderstorms, when lightning flashes compete with daylight and are hard to see. The National Collegiate Athletic Association handbook of lightning safety says thunder should prompt an evacuation of the field and that the refuge of a safe shelter should be sought. Furthermore, the handbook recommends that outdoor activities not resume until 30 minutes after the last rumble of thunder.

ASK TOM: Chicago area’s April 1961 snowstorm

Dear Tom,

Your column about the April 2-3, 1975 snowstorm reminded me about an April 16, 1961 snowstorm when my fiance and I were stranded at my parent’s Chicago Heights home after our engagement party. Details?

— Bonnie Zarch, Skokie

Dear Bonnie,

The Chicago area recorded its largest latest-in-the-season snowstorm when 6.8 inches fell April 15-17, 1961. The bulk of the snow came down on April 16, when the city’s official site at Midway Airport measured 5.4 inches. The heavy, wet snow, piled into 5-to-10-foot-high drifts by winds gusting to 50 mph, shut down many area roads. The snow was heaviest south and east of Chicago with 5-to-9-inch totals common between Chicago and Indianapolis. But temperatures quickly rebounded into the 60s, melting the snow within a day or two.

ASK TOM: Why are people who predict and report the weather called meteorologists?

Dear Tom,

Why are people who predict and report the weather called meteorologists? Meteors are rarely mentioned.

— Jack, Orland Park

Dear Jack,

It’s been a while since we’ve addressed this question. The derivation of many English words can be traced back to ancient languages and cultures.

The word meteorology dates back to ancient Greece — around 340 B.C., when Aristotle wrote “Meteorologica,” which covered that era’s knowledge of weather and climate along with related disciplines of geology, astronomy and oceanography. He was interested in observed atmospheric phenomena such as clouds, rain, snow, thunder, wind and rainbows. Ancient Greeks referred to any particles suspended or falling through the air as meteors; the terms meteorology and meteorologists came from his work.

ASK TOM: The late-season snowstorm of April 2-3, 1975

Dear Tom,
I remember an April snowstorm in either 1974 or 75 that clogged expressways, stranding many on their way home from work. Do I remember correctly?
— William Meyer

Dear William,
You’re thinking of the late-season snowstorm that blasted the Chicago area on April 2-3, 1975, with the official snowfall total of 9.8 inches at Midway Airport. Snowfall was even heavier to the north and west where 11 inches of snow closed O’Hare International Airport and more than a foot piled up in some north and northwest suburbs.

The storm came as quite a shock to Chicagoans as it followed more than a week of mild spring weather that included highs of 74 on March 21 and 62 on March 31. The snow, which began as a mixture of rain and sleet, was heavy and wet; at least eight people died of heart attacks while shoveling.

ASK TOM WHY: How did the storm that wrecked the Edmund Fitzgerald affect Chicago?

Dear Tom,

I was driving yesterday when I heard the Gordon Lightfoot song the “Wreck of the Edmund Fitzgerald”. How did that storm affect Chicago?

Art Azen

Dear Art,
The Edmund Fitzgerald sank in a legendary late autumn storm on Lake Superior about 17 miles northwest of Whitefish Point, Mich., on Nov. 10, 1975. As cold air swept across the lake in the storm’s wake, west winds reached 80-90 mph, speeds equivalent to a Category 1 hurricane. The high winds generated 25-30 foot waves that proved too much for ship, which took its crew of 29 to a watery grave. Chicago was in the warm sector of the storm and received some rain and thunderstorms. Gusty south winds to 46 mph boosted the mercury into upper 60s and lower 70s but in the wake of the storm temperatures crashed into the lower 30s bringing the city its first measurable snowfall of the season.

ASK TOM: Describing the sound of tornadoes

Dear Tom,

“It sounded like a freight train” is a typical description of the sound produced by a tornado, but how did pre-industrial people describe it?

— Rich McConnell

Dear Rich,

Historical accounts in pioneer and Colonial times liken the sound of tornadoes to the hum of billions of bees, the roar of hundreds of waterfalls or the continuous boom of cannons.
Sound recordings with modern video cameras and similar equipment indicate the sound of a tornado would be more accurately described as a strange hissing or whistling similar to the sound generated by an open car window when the vehicle is traveling as a very high speed. Some tornado survivors say they could actually feel vibrations against their faces, causing a tingling or stinging sensation.