Prince George's County Executive Lawrence J. Hogan is expected to announce a budget surplus as great as $8.3 million today but predict a severe fiscal crisis next year as a result of voter-approved taxing limitations.

The surplus will offset only a relatively small portion of massive cost increases that could cause cuts in services up to $28 million and layoffs of county government workers, according to sources familiar with new budget projections.

The spending squeeze, resulting from the tax-limiting TRIM county charter amendment approved by the voters last fall, will be far worse than this year, the first year TRIM had an effect, according to the sources.

The taxing limitations persuaded county officials to accept a number of controversial economy measures such as school closings, classroom teacher reductions and reduced park services in the current fiscal year, which ends next June 30.

Prince George's is the only Washington area jurisdiction where voters have approved property tax curbs modeled on California's Proposition 13.

Hogan's announcement of the projected surplus is likely to produce criticism from County Council members and legislative leaders who maintained throughout last spring's tense budget negotiations that Hogan was underestimating the amount of funds the county would have available to spend this year.

County officials are preparing to defend the surplus as the result of austerity measures put into effect after this year's budget was adopted rather than a miscalculation of revenues. They maintain that the austerity must be tighter still in the face of the revenue restrictions forced by the TRIM amendment.

TRIM limits property tax collections -- the largest single source of county funds -- to the amount collected last year. That means that the county budget cannot grow as costs increase unless other revenue sources are found.

Next year, according to the new revenue estimates, the county's funds will increase by a maximum of $9.5 million -- or 2 percent -- while the county will have as much as $37.5 million in additional bills, not including the cost of an estimated inflation rate of more than 10 percent.

The funding gap has already caused Hogan's staff to begin setting new manpower levels in county departments far below the number of employes budgeted for this year.

County department heads have already been told to submit budget plans for next year that reduce spending by as much as 15 percent from this year.

Hogan has scheduled a meeting today with the county's legislative delegation to Annapolis and the County Council to explain the new budget projections. He will also deliver a "wish list" of state funding requests to the legislators that officials say they need to keep the county operating in 1981.

Hogan ordered early budget estimates and scheduled the meeting in an effort to improve his relations with the all-Democratic state delegation, which last year feuded with the Republican executive over important funding issues while its members complained that Hogan never made his legislative priorities clear.

County officials say they think an early start is made especially urgent because of the problems they foresee from the TRIM amendment.

This year's combined county school and government budget totals $458 million. Among substantial cost increases projected for next year are:

$10 million for cost-of-living raises promised school employees.

An additional $7.5 million for salary step increases for county employees.