Washington, baked by a continuing heat spell broken intermittently by fleeting thunderstorms, coped with the elements again yesterday with resignation, chagrin, humor and resourcefulness.

Yesterday's temperatures, rising to 94 degrees shortly before noon, extended the stretch of broiling June and July weather - an uncomfortable period in which thermometers already have reached or broken 90 degrees on 11 of the past 12 days. Yesterday also brought the summer's worst air pollution so far - a peak of 140 on the area's air quality index, recorded in Alexandria at 3 p.m.

Weather forecasters say they do not expect relief from the heat wave before end of the weekend. Hot and humid weather was predicted for today, with highs near or above 100 degrees. The area's air pollution alert, which started Tuesday, was extended through today. Harold Hess, a National Weather Service forecaster, said the only apparent hope for a break in the weather is a cool Canadian air mass, now situated over the Dakotas and Montana, which might reach the Washington area by Sunday.

A brief burst of midafternoon thunderstorms yesterday left more thar disruptions, they said, included Springfield, and Fallstilities officials. The communities hit by electric power disruptions, they said, uncluded Springfield, and Falls Church in Virginia, Potomac in Maryland and the Congress Heights area of Southeast Washington.

Heavy winds and lightning also were reported to have caused scattered boating accidents and fires. Four sailboats capsized at Ft. Washington marina, on an inlet of the Potomac River in Prince George's county, authorities said. Lightning set fire to two Fairfax County homes, causing several thousand dollars in damages, officials reported. In the Brunswick area of Frederick County, winds blew, the roof of a bowling alley. No injuries were reported.

Though the scattered rainfall brought temporary relief. Washingtons were left to contend with the heat during most of the day. They took off their shoes, spread umbrellas to provide shade, Crowded city swimming pools, mopped their foreheads, hurried to get inside air-conditioned buildings, turned on fans, slowed their pace, sweated grumbled and joked.

It was so hot that Steve Point, a carpenter helping renovate a Washington Circle NW townhouse, had taken off his green T-shirt and wrapped it around his neck to soak up the sweat. He vowed he would come to work in shorts today. "If I could work in a bathing suit, I would," he added.

It was so hote that Fred K. Lambert asked passengers how many pounds they wanted to lose - by sweating off fat - as they boarded his bus. Lambert a driver on a D-4 Meirobut line, wiped his forehead with a green washcloth. He complained about the air-conditioning, which he said worked unadequately. He also complained about some passenger. They open the windows up and won't let the bus get cool," he said.

Yet Lambert's most effective means of coping seemed to be good humor. He told passengers they would lose more weight if they moved to the back of the bus - its hottest spot.

It was so hot Anne McKnight, a social worker who is off on Thursdays, took six children, including two of her own, to a city swimming pool. Her Mount Pleasant home has no airconditioning, she said.

It was so hot that - because of a quirk in the ice cream business - Swensen's an ice cream parlor on Wisconsin Avenue in Georgetown, was doing usually little business. The heat and smog kept people off the streets. Paul d'Eustachio one of the shop's managers said. So, few passer by stopped in for ice cream. "We do most of our business when it's a beautiful, 70-degree clear lay," he added.

Jeannie Combs, a secretery at the National Cancer Institute whose airconditioning was shut of balance of suburban Maryland's water breaking. Set up a fan beneath the desk where she was typing. John Swift, a United Parcel Service deliveryman, hurried to get his package inside air-conditioned buildings for temporary relief from the heat.

In Orange, Va., three staff members of radio station WMJA set about the proverbial stunt for frying eggs on the hood of a car. The station interrupted its regular broadcasts for occasional "egg updates".

According to weather forecaster Hess. Washington's blistering heat stem from a simple and temporarily insoluable problem: a stagnant blanket of hot, sticky air sat down over Washington a few says ago and has refused to budge. The intermittent thundershowers, which brought bail to London County - yesterday are part of the same troubling weather phenomenon, He added.

The hot air near the ground rises, carrying with it the humidity that has tsocked Washington for days. As the hot, soggy air climbs through ecoler air above, its moisture turns to raindrops, loosing the storms that have briefly swept the area at afternoon and evening .

Despite the severity of some of the thunderstorms, Washington's rainfall has remained skimpy, amounting to less than 1/4 of an inch yesterday. Frank Forrester, information officier for the U.S. Geologicial Survey, said that yesterday's rainstorms were too localizied and isolated to have a significant effect on the Potomac River, not all usually low levels.

Washington's weather difficulties have combined, as they usually do with automobile exhausts to produce air pollution. The pollution has largely been blamed on what are known as photochemical oxidations. These results when hydrocarbons and nitrogen oxides - products of auto exhaust - are acted on by sunlight.

According to Dennis R. Bates health and environmental protection director for the Metropolitan Washington Council of Governments, the area's air quality index broke the 100 mark at the Alexandria's summer record of 140. The other two were reading of 125 in Suitland and 105 in Fairfax County, Bates said. At this level, Washington's air is officially termed "very unhealthy."

Use of electric power boosted by reliance on air conditionings, set two records in the Washington area this week. Both the Potomac Electric Power Co. and the Virginia Electric Power Compay reported that they had record electric consumption on Wednesday.

Washington's temperature did not set a record yesterday. The 94 degree high fell 4 degrees short of a 96 degree mark recorded on July 7th 1925. Today, there may be hope, of an uncomfortable sort. The previous record was 96. set in 1890. The National Weather Service has forecast that today's high temperatures may climb to 102 degrees.