Through midnight Thursday, parking on certain streets will be restricted to those holding official police parking permits. The affected areas are east curb of 15th Street NW between Constitution and Pennsylvania avenues; C and D streets NW, between 17th and 18th streets; east curb of Jackson Place NW, between Pennsylvania Avenue and H Street. Vehicles without an official permit may be ticketed and towed.

Metrobus route changes: With 16th Street NW blocked off in front of the Soviet Embassy, four routes will detour between L and M streets. Northbound buses will use 15th Street NW, and southbound buses will be rerouted to 17th Street NW. The routes affected include S-1, S-2, S-4 and G-4. RALLIES TODAY

In Lafayette Park, these rallies are planned: Paul Wong/Christian Group; the Islamic Revolutionary Movement, protesting the Soviet military presence in Afghanistan; Crimean Tatar Association, asking the Soviets to grant them rights; Baltic groups, candlelight vigil protesting Soviet repression in their homeland; Union of Oromos, protesting Soviet intervention in Ethiopia; the International Society for Krisha Consciousness, and Cure AIDS Now, asking more money to cure acquired immune deficiency syndrome.

The Student Struggle for Soviet Jewry will hold a rally near the Soviet Embassy. Halim Saylik Crimea Tatar Association will picket on the White House sidewalk.