Northern Virginia is expected to gain more influence and support for its transportation programs and other needs because of the uncertain role powerful Sen. Edward E. Willey will play in state government in the coming months, area officials said yesterday.

Willey, 76, the Richmond Democrat who has maintained a vise-like grip on state spending as chairman of the Senate Finance Committee and who is the chairman of a gubernatorial task force studying highway financing, suffered a severe stroke Monday. He remained in serious but stable condition yesterday at a Virginia Beach hospital.

While area officials expressed concern over Willey's condition, they said his absence from the special legislative session on transportation in September and next year's regular session could mean increased funding for Northern Virginia and other suburban areas.

"I think it will make it easier for us to obtain the funding we need" for many state programs, including roads, social issues and higher education, said state Sen. Clive L. DuVal 2nd (D-Fairfax), chairman of the Northern Virginia caucus.

Officials said Willey was partly paralyzed and unable to speak yesterday. His recovery is expected to take several months.

DuVal, who said Willey had been less hostile to the Washington suburbs in recent years, said Willey's absence would alter the debate in Richmond over a broad range of issues.

"There's been inactivity on the state level" on road financing, said Fairfax County Board Chairman John F. Herrity, a Republican. "And to some extent, Ed Willey represents that attitude. "You need a much more creative approach."

Virginia contributed about $21 million a year -- a small fraction of the total cost -- to support funding for Metrorail, an amount that has been largely unchanged since 1982.

Even that sum was approved only after Willey suffered a heart attack in 1982, sidelining him for the legislative session that year.

"You might say he hasn't been a good friend of Metro in the past," said Metro Board member Joseph Alexander, a Democratic member of the Fairfax Board of Supervisors. Alexander said Willey's absence "will give us an opportunity to do more for transit in general."

DuVal also said Northern Virginia's educational institutions, particularly George Mason University and the Northern Virginia Community College system, also could expect more favorable treatment as political power shifts from old-line Richmond and rural conservatives to ranking senators from Northern Virginia and Tidewater, another rapidly developing suburban area of the state.

DuVal and other officials also predicted they would encounter less opposition on social issues, such as mental health financing and Aid to Families with Dependent Children.

A year ago, area lawmakers stepped up efforts to woo Willey's favor. They spent a day whisking Willey around the region in an unpublicized, red-carpet visit, flying him in on a small private jet and toasting him at a luncheon attended by the area's leading politicians, business executives and developers.

Local officials have been concerned that Willey's opposition to floating bonds and dramatic new spending for highways could stifle the area's growth.

Not all Northern Virginia officials agreed that Willey's illness would translate into fewer obstacles for the region in the state legislature.

"Willey's been a good friend to all of us up here," said Sen. Richard L. Saslaw (D-Fairfax). "We've lost an ally for the time being."

Saslaw cited Willey's support for a massive reallocation of the state's highway funding formula in 1985 that funneled millions of new dollars into urban areas, including Richmond, at the expense of rural areas. "He was there when we needed him," Saslaw said.

Willey, a retired pharmacist, has been in declining health for years and was hospitalized during the 1986 session because of influenza. He previously received a pacemaker and underwent surgery on his veins. In recent months, Willey has relied on one or two persons to assist him while walking and usually is driven the distance of 125 yards from the State Capitol to the legislative building in Richmond.