TWO 19th century burgundies, a rare 20th century claret and a bottle of Hungarian Tokaji from the "birth year" of the Washington Monument will be uncorked here Thursday at a preview tasting of wines to be offered at this year's Heublein Premiere National Auction of Rare Wines in Los Angeles next month.

The four-hour tasting--which begins at noon at the Sheraton Washington Hotel--is one of three preview tastings (in addition to Miami and Los Angeles). The Washington tasting will feature more than 141 wines from Europe and America, including such notables as 1897 Inglenook cabernet sauvignon; 1899 Chateau Haut-Brion; 1919 La Tache, 1924 Chateau Margaux, 1928 Chateau d'Yquem, 1959 Chateau Petrus and a vertical array of B.V. Private Reserve cabernet sauvignon dating from the 1964 California vintage.

While purchase of the 153-page 1983 Heublein catalogue entitles one to admission at the tasting ($40 at the door), the price of this bacchanalian marathon also may include standing in long lines or elbowing some of the 500 competing tasters, if Heublein's two previous Washington tastings are any indication.

At least one guest who will not have to negotiate his way around the bottle-laden tables tomorrow is John Augustin Washington, a descendant of the first First Family, who will be permitted the first sip of the Hungarian Tokaji from 1855, the year that the obeliskan monument to his famous forebearer was dedicated.

All the profits from this year's sales of more than 17,000 bottles--the world's single largest annual wine auctions--will go this year to the Mount Vernon Associaton to aid in the preservation of George Washington's historic estate. Collector copies of the illustrated catalogue, which also serve as admission to the May 26 auction in Los Angeles, can be obtained (for $35) from Heublein Inc., Box 505, Farmington, Conn. 06032.