Gasoline supplies may be tighter this weekend in the Washington area than on any previous weekend during the current shortage, according to the American Automobile Association.

Prices continue to soar, with several area stations charging 99.9 cents a gallon for premium gasoline yesterday. "It's looking bad for this weekend," said the AAA's local spokesman Glenn Lashley. "We're putting out a special appeal this weekend for motorists not to top off their tanks. This is going to be the tightest weekend we've had."

Motorists planning weekend trips outside the Washington area will find stations open around the clock on most interstate highways, but many such stations are limiting individual sales to between $3 to $8.

There is sufficient gasoline available in Ocean City and most other resort areas, according to reports.

Eighty percent of the Washington area's estimated 1,500 service stations will be open Saturday, but only 5 percent will be open Sunday, according to an AAA telephone poll of dealers.

The Sunday figure represents a sharp drop from previous weekends, and it may go even lower if dealers who are now planning to remain open Sunday have heavy business on Friday and Saturday, according to the AAA and local dealer associations.

On Saturday, most stations plan to close by noon or early afternoon. Virtually all should be closed by nightfall.

The AAA and local dealer associations declined to release lists of stations planning to stay open over the weekend, saying that listing them publicly could cause a run on them, thus forcing them to close.

"If something were published, we'd be flooded [with customers]," said Roy Page, a Northern Virginia Exxon dealer and local representative of the Virginia Gasoline Retailers Association.

Page said dealers usually will disclose their daily opening time - usually 7 or 8 a.m. - but not their proposed closing time. Instead, dealers tend to close immediately after pumping the daily proportion of their monthly fuel allocation in order to stretch supplies through the month.

Unleaded gasoline is in shorter supply than regular and premium this weekend. Of the 66 stations that the AAA checked in order to compile its weekly statistics, dealers at 8 percent said they were out of unleaded gasoline. No dealer said he was out of regular or premium.

Generally, more stations will be open in the Virginia suburbs this weekend than in the District of Columbia or the Maryland suburbs. The AAA and local officials don't know why.

Washington area gasoline prices increased an average of 1.35 cents a gallon in one week. OnWednesday the average prices here were:

FULL SERVICE(TABLE) *3*FULL SERVICE (COLUMN)(COLUMN)Price increase (COLUMN)(COLUMN)during past (COLUMN)Price(COLUMN)Week Regular(COLUMN)85.6 cents(COLUMN)1.3 cents Premium(COLUMN)92.4 cents(COLUMN)1.3 cents Unleaded(COLUMN)89.9 cents(COLUMN)2.2 cents (COLUMN)SELF-SERVE(COLUMN) Regular(COLUMN)82.6 cents(COLUMN).7 cents Premium(COLUMN)89.8 cents(COLUMN)1.2 cents Unleaded(COLUMN)87.7 cents(COLUMN)1.4 cents(END TABLE)

The high on Wednesday was 99.9 cents a gallon for full-service premium, and the low was 77.9 cents for self-serve regular in the AAA survey.

One Northwest Washington Gulf dealer whose price was 99.9 cents a gallon for premium yesterday said that the price will soon go over $1 a gallon at his station. Because his pump dials cannot register prices over $1, the dealer said he will set the dials to register half price and then charge double the amount shown on the dials.

He said his Gulf supplier would give him brochures to hand out to customers to explain the procedure. CAPTION: Map, Gas Limits, By Dave Cook - The Washington Post