In many American cities, the most popular TV weather forecaster is not a meteorologist. Formal training in meteorology isn't really essential in the TV forecasting business.

A pretty girl or a fat man with a sense of humor can do just as well, provided these "personalities" have acquired an ability to read and pronounce basic English. That's what the National Weather Service uses in disseminating its forecasts.

The Weather Service is not always right. Neither are nongovernment meteorologists. Ouija board operators, astrologers, people who read tea leaves, and those who suffer from arthritis or rheumatism are also wrong occasionally. In a contest between Gordon Barnes' radar screen and the intermittent pain in my hip, it's a close call as to which would forecast rain with greater accuracy.

Frank Forrester of the U.S. Geological Survey is a meteorologist who does not serve the Survey in that capacity but retains his interest in the science. A few days ago, Frank came across a news item about Preston J. Shallcross, 97-year-old resident of Rock Hall, Md., whose long-range forecasts have been impressively accurate in recent years.

The secret of the nonagenarian's success is the secondary use he makes of the young goose he eats each Thanksgiving. While you and I are having turkey, Shallcross is eating a domestic goose born the previous spring. He says, "A wild one won't do because you can't tell how old it is." s

Shallcross examines the breastbone of the young goose and bases his forecasts on his findings. After Thanksgiving of 1979, he said, "This year's bone was one of the lightest I've ever seen, except toward the end, where it got very dark. It will be a mild winter until February, when there will be an abrupt change to winter weather that will extend into March." t

Forrester is mildly impressed, but asks, "Shall I confess all, and tell you that my favorite forecaster was my wife? If she complained about a sore elbow: precip. If she washed clothes: fair." HISTORY LESSON

A reader has taken exception to my recent reference to Calvin Coolidge's election to the presidency.

"I don't go back that far (I'm in my 20s)," the reader wrote, "but my recollection of history is that Coolidge was never elected president.He was elected vice president and became president when Harding died."

Your memory has done you dirt, sir.

When Harding died on the night of Aug. 2, 1923, Coolidge was visiting his father's farm in Plymouth Notch, Vt.

By the light of a kerosene lamp, Coolidge was sworn in by his father at 2:47 a.m. on Aug. 3.

He served out Harding's term and in 1924 was elected to a full term of his own.

For a while, he kept the country guessing about whether he would run for another term. In 1927, he tried to end the suspense by issuing one of his typically terse statements: "I do not choose to run for president in 1928."

But Washington's political pundits read many meanings into that simple sentence. Some said it meant that while Coolidge didn't choose to run, he would run if there seemed to be significant support for his candidacy. Others thought the hidden meaning was that he didn't want to run in 1928 but would be a candidate again in some subsequent election. One, I recall, thought Coolidge was hinting he would run for the Senate.

Eventually, the nation realized that Coolidge was not going to run, period.

His secretary of commerce, Herbert Hoover, ran and won.

Poor Calvin went to his grave wondering what you have to do to make yourself understood in Washington.

Alas, he was neither the first nor the last who tried but failed to "make one thing perfectly clear." THE PICTURE PEOPLE

I am distracted from a movie's story line when a character enters a house and fails to close the door behind him.

Normal people don't do that, so I find myself wondering, "Is the author telling me this guy is as irresponsible as a 6-year-old? Is the open door part of the plot? Is that how the bad guy will get into the house?"

When the answer turns out to be "None of the above," I am puzzled. Why show an action that distracts viewers from the basic story?

Col. Dane O. Sprankle and Joseph B. Jordan have a similar reaction to a current TV commercial for LBT oil additive. An actor is shown pouring the stuff into his engine through a funnel. Then, with the funnel still in place and the opening in the valve cover still uncapped, he slams down the car's hood and is ready to roll!

I wonder how much they paid the genius who thought up that one. THESE MODERN TIMES

I'm reminded of Dave Strong's report on gasohol: "My carburetor used to sputter. Now it hiccups."