If last July wasn't hot enough for you, read this

Just in case the summer of '83 stays cool, the weather forecasters have invented a new way to make us feel hot and bothered. This aggravation, adopting the jargon of the times, calls itself the ''weather-stress index.''

Veterans in the audience will remember banging their primitive wooden radios to produce gleefully gloomy prophecies, like, ''Boy, is it ever going to get hot!'' Temperature was the weatherman's only weapon of intimidation in the old days.

Then, as the scare effect of hot, hotter, hottest wore off - even when raised to such rhetorical excesses as ''torrid,'' ''tropical,'' and ''sweltering'' - the growing army of media meteorologists had to devise another scale to escalate a summer's menace. Ever since the Ice Age melted and evaporated, producing all that steam, ordinary people, we can assume, spoke of things getting ''sticky'' and ''muggy.'' Belatedly the weather witch doctors picked up on this damp idea, gave it a pseudo-scientific cast, and voila! - humidity got discovered.

As we entered the Television Age, the pioneers with pointers and pull-down charts and old-fashioned blackboards leered at us like 1890s villains as they threatened: ''Tomorrow's not going to be too hot, temperature-wise. But whew, will it feel humid!''

Sensitive folk broke into a sweat at the very sound of the word.

Still, that was a technological millennium ago. The blackboard has long been replaced by satellite photography and computer scans, leaving the double wham-my of hot-and-humid as dated as the bow-and-arrow. The meteorologists' industry evidently took this as a challenge: If we can put a man on the moon, why can't we make him really hot, Space-Age style?

And now the response is in. Despite these austere times, the government, as we understand it, has paid out the taxpayer's money to reward the meteorologist who could make the taxpayer feel clammiest. A professor at the University of Delaware's Center for Climatic Research, who shall go nameless, turned out to be the winner - in a manner of speaking. Under contract to the National Oceanic and Atmospheric Administration, the fiend perfected the notion of ''apparent temperature.'' This means that, even if the temperature and humidity aren't too cruel, other ''stressful'' factors - like the lack of a cooling breeze - can be figured in to make you squirm as if the summer were soaring permanently into the upper 90s.

''Weather-stress index'' is defined as the measurement that tells us ''how far from normal the weather will feel.'' As a summertime gift, this ranks with a broken air conditioner. And just wait until the weather-stress index hits the winter. In the arsenal of meteorological overkill, weather-stress index will make wind-chill factor seem like a bean-blower.

What quirk makes us keep saying, ''Have a nice day,'' on the one hand, while practically begging the forecasters to pronounce the hex of weather-stress?

Why do the forecasters themselves prefer gales, blizzards, tornadoes, and general mischief to the serenity of a cloudless sky?

These are not exactly the key issues of 1983. But, like our fondness for J.R. and our taste for video games about World War III (or IV), our determination to make weather threatening rather than benign says something about our contrary attitude toward life.

Call us lovers of the storm (and stress). First the bad news . . . and then the bad news. Is that really any way to live?

If we can't be merciful to ourselves, we should take pity on the post office. Snow, rain, and night are enough. It's not fair to ask our mail deliverers to promise that the weather-stress index won't keep them from their appointed rounds.