Boston — It looks like people in New Jersey and Florida, who have been in the grip of prolonged drought, will be able to water their lawns this summer.
Because of plentiful rains, there is good news on the water front. While no one is advocating the wet stuff be squandered, it appears that unless the weather is excessively hot and dry this summer, there will be plenty to go around in most areas of the United States.
That means that for states like New Jersey it's going to be all right to break out the hose and wash the family car or water the lawn again, environmental officials say.
Moreover, moisture in the ground, essential to agriculture, seems to be normal for this time of year, except in areas of New York State, the Carolinas, and the Southwest. Some areas of the Midwest are reporting unusually wet conditions.
Says Carroll Saboe of the US Geological Survey in Reston, Va., only half-seriously: ''It is ill-timed to be looking at the question of drought.''
Indeed, with few exceptions, stream flows across the US are at normal or above normal levels for this time of year -- some of them for the first time in nearly two years. The only reports of below-normal conditions as of June 1 were in northern Wyoming and northwestern Montana and from one station each in Arkansas and Louisiana, Mr. Saboe says.
The National Weather Service predicts warmer than normal temperatures across most of the US this summer, according to Donald Gilman of its Climate Analysis Center. Only the Pacific Northwest seems likely to be cooler than normal.
Rainfall from June through August, Dr. Gilman says, may be ''deficient'' in parts of the Southwest and from Virginia to northern Florida. But he predicts the Northwest, most of Texas, and the area from the Dakotas east to the St. Lawrence Valley may be in for a wetter than usual summer.
Unless summer rains are unusually heavy, however, they generally do not ''recharge'' water supplies, since most of the moisture is lost through evaporation and transpiration.
Some of the areas that are in the best shape at the moment are the same ones that were experiencing serious droughts only a year ago, especially Florida and the 13,000 square-mile area of New York, New Jersey, Pennsylvania, and Delaware drained by the Delaware River.
Eric Livingston, an environmental specialist with the Florida Bureau of Water Resources Management, says limits on consumption have been lifted in most sections of that state. They had been in effect for most of the past six months.
The water table across the state is still low, Mr. Livingston says, but is ''coming back up; it's not as bad as a year ago.'' No major sinkholes -- the result of an excessively low table -- have been reported in central Florida since April.
Lake Okeechobee, the main water supply for south Florida, is still five feet below its normal stage, Livingston says, but the state is just entering its rainy season, which typically lasts until October.
Spokesmen for the Delaware River Basin Commission in Trenton, N. J., report area reservoirs are so full -- 90 percent of capacity or better -- that all water usage restrictions were called off in late April. At the lowest point of the drought in the four-state region, February 1981, reservoir storage was a dangerous 25 percent of capacity.
''It's excellent,'' says water resources engineer John Rattie. ''There is no deficit whatsoever. Not that (the rainfall) was all that heavy, but it was the way in which it fell; we were able to store it.''
But Basin Commission geologist Page Fielding says that the water supply is still being overtaxed in heavily developed areas of southeastern Pennsylvania, where underground limestone formations prevent sufficient storage of rainfall. Restrictions there are still in force, he says.
In New England, which has been buffeted by record heavy rains this month, water supply conditions are gradually improving. Connecticut has had so much rain that some lives were lost and local flood emergencies had to be declared.
In Massachusetts, the previous record for rainfall in June was broken before mid-month, but 24 cities and towns continue to face official ''emergency shortages.''
The state has recently observed ''Water Conservation Week,'' but the huge Quabbin Reservoir, supplier of water to 43 communities, including Boston, is at 97 percent of capacity. Environmental Affairs Secretary John A. Bewick says recent rains ''may finally have washed away the dry spell, but we need better water management to prevent future shortages -- and conservation is the wisest place to begin.''
However, at least one area -- the Midwest -- may have received too much moisture. Soaking rains, followed by subnormal temperatures, have combined to delay planting.