Washington: Today - Mostly sunny, high near 80, low in low to mid 60s. Chance of rain is 10 per cent through tonight. Saturday - Mostly sunny, high near 80.

Maryland and Virginia: Today - Mostly sunny, highs near 90, lows in 60s. There is a chance of rain late today in the north. Saturday - Mostly sunny, highs near 90.

Lower Potomac and Chesapeake Bay: Today - Fair skies with visibility of 2 to 5 miles and westerly winds at 20 knots or less.

Extended Area Outlook: For Sunday through Tuesday - Cloudy with rain likely at times and highs in 70s, lows in 50s through the period. Washington's normal temperature range for this time of year is from 76 to 53.

West Virginia: Today - Mostly sunny, highs in mid 70s to mid 80s, lows in 50s. Becoming partly cloudy with chance of rain tonight. Saturday - Chance of rain, highs in 70s to low 80s.

The National Weather Forecast for Today - Rainshowers will be spread from the upper Missouri Valley and northern two thirds of the Rockies through the Pacific Coast from central California through Washington. Showers and thunderstorms will extend from east portions of Oklahoma and Kansas through the south and central Mississippi Valley, across the Gulf of Mexico states through the Ohio Valley and the northeast from Pennsylvania through New England. Temperatures will be warm from the Appalachians through the Atlantic Coast states except New England. It will be cool from the west end of the Great Lakes through the northern two thirds of the Rockies, across the intermountain region and the Pacific Coast. Elsewhere, temperatures will be seasonably mild.

The Council of Governments' Air Quality Index for yesterday showed the high reading in the Washington area during the 2 to 3 p.m. period was 38 for the pollutant, photochemical oxidants. Index values between 25 and 49 indicate fair air quality. When the index exceeds 100 the air becomes hazardous and persons with lung, heart and eye problems should restrict their activity. The forecast for today indicates the air quality will improve.

The National Weather Service forecasts that the Potomac River stage at Little Falls will remain near 3.6 feet through today.

Washington data at 8 p.m. (EDT) yesterday: Highest temperature since 8 a.m. yesterday, 83 degrees at 2:40 p.m. Lowest temperature since midnight, 65 degrees at 5:20 a.m. Excess of temperature since May 1, 28 degrees. Excess of temperature since Jan. 1, 128 degrees. Record high temperature for today, 93 degrees in 1950. Record low temperature for today, 37 degrees in 1911. Relative humidity: Maximum, 97 per cent at 6 a.m.; Minimum, 53 per cent at 3 p.m. 24 hour precipitation .01 inches. Excess of precipitation since May 1, .24 inches. Deficiency of precipitation since Jan. 1, 4.03 inches. Highest observed wind since 8 a.m. 12 miles per hour from the South at 12:55 p.m. Peak gust since 8 a.m., 22 miles per hour from the S.W. at 4:52 p.m. Local Temp., Humidity(TABLE) Time(COLUMN)T.(COLUMN)H. 12 midn.(COLUMN)67(COLUMN)90 1 a.m.(COLUMN)66(COLUMN)93 2 a.m.(COLUMN)66(COLUMN)93 3 a.m.(COLUMN)66(COLUMN)93 4 a.m.(COLUMN)66(COLUMN)93 5 a.m.(COLUMN)66(COLUMN)93 6 a.m.(COLUMN)65(COLUMN)97 7 a.m.(COLUMN)66(COLUMN)93 8 a.m.(COLUMN)66(COLUMN)93 9 a.m.(COLUMN)69(COLUMN)84 10 a.m.(COLUMN)72(COLUMN)76 11 a.m.(COLUMN)74(COLUMN)74 12 noon(COLUMN)74(COLUMN)76 1 p.m.(COLUMN)78(COLUMN)69 2 p.m.(COLUMN)80(COLUMN)62 3 p.m.(COLUMN)83(COLUMN)53 4 p.m.(COLUMN)81(COLUMN)65 5 p.m.(COLUMN)79(COLUMN)69 6 p.m.(COLUMN)78(COLUMN)74(END TABLE) Temperatures ending 8 a.m. (EDT) yesterday:(TABLE) City(COLUMN)H.(COLUMN)L. Albany(COLUMN)68(COLUMN)49 Albuquerque(COLUMN)80(COLUMN)54 Amarillo(COLUMN)83(COLUMN)56 Anchorage(COLUMN)53(COLUMN)35 Asheville(COLUMN)73(COLUMN)51 Atlanta(COLUMN)81(COLUMN)57 Atlantic City(COLUMN)54(COLUMN)51 Austin(COLUMN)85(COLUMN)69 Baltimore(COLUMN)63(COLUMN)59 Billings(COLUMN)61(COLUMN)35 Birmingham(COLUMN)80(COLUMN)62 Bismarck(COLUMN)76(COLUMN)43 Boise(COLUMN)52(COLUMN)35 Boston(COLUMN)61(COLUMN)50 Brownsville(COLUMN)86(COLUMN)71 Buffalo(COLUMN)66(COLUMN)46 Burlington, Vt.(COLUMN)68(COLUMN)42 Casper(COLUMN)57(COLUMN)31 Charleston, S.C.(COLUMN)84(COLUMN)69 Charl'ton, W. Va.(COLUMN)72(COLUMN)63 Charlotte, N.C.(COLUMN)81(COLUMN)61 Cheyenne(COLUMN)57(COLUMN)39 Chicago(COLUMN)72(COLUMN)60 Cincinnati(COLUMN)76(COLUMN)61 Cleveland(COLUMN)67(COLUMN)51 Columbia, S.C.(COLUMN)89(COLUMN)67 Columbus, Ohio(COLUMN)73(COLUMN)63 Dal.-Ft. Worth(COLUMN)89(COLUMN)72 Dayton(COLUMN)74(COLUMN)60 Denver(COLUMN)74(COLUMN)42 Des Moines(COLUMN)76(COLUMN)55 Detroit(COLUMN)54(COLUMN)50 Duluth(COLUMN)62(COLUMN)46 El Paso(COLUMN)86(COLUMN)57 Fairbanks(COLUMN)51(COLUMN)35 Fargo(COLUMN)73(COLUMN)52 Flagstaff(COLUMN)67(COLUMN)38 Great Falls(COLUMN)56(COLUMN)34 Hartford(COLUMN)73(COLUMN)52 Helena(COLUMN)52(COLUMN)33 Honolulu(COLUMN)85(COLUMN)74 Houston(COLUMN)82(COLUMN)69 Indianapolis(COLUMN)78(COLUMN)60 Jackson, Miss.(COLUMN)84(COLUMN)66 Jacksonville(COLUMN)84(COLUMN)62 Juneau(COLUMN)56(COLUMN)34 Kansas City(COLUMN)78(COLUMN)68 Las Vegas(COLUMN)84(COLUMN)60 Little Rock(COLUMN)79(COLUMN)68 Los Angeles(COLUMN)71(COLUMN)57 Louisville(COLUMN)80(COLUMN)67 Memphis(COLUMN)82(COLUMN)72 Miami Beach(COLUMN)76(COLUMN)74 Midland(COLUMN)90(COLUMN)59 Milwaukee(COLUMN)54(COLUMN)46 Mpls.-St. Paul(COLUMN)69(COLUMN)55 Nashville(COLUMN)78(COLUMN)67 New Orleans(COLUMN)84(COLUMN)65 New York(COLUMN)63(COLUMN)49 Norfolk(COLUMN)77(COLUMN)65 North Platte(COLUMN)78(COLUMN)83 Oklahoma City(COLUMN)81(COLUMN)67 Omaha(COLUMN)79(COLUMN)52 Orlando(COLUMN)86(COLUMN)63 Philadelphia(COLUMN)59(COLUMN)55 Phoenix(COLUMN)90(COLUMN)68 Pittsburgh(COLUMN)64(COLUMN)58 Portland, Me.(COLUMN)58(COLUMN)34 Portland, Ore.(COLUMN)56(COLUMN)42 Providence(COLUMN)62(COLUMN)50 Raleigh(COLUMN)82(COLUMN)61 Rapid City(COLUMN)74(COLUMN)37 Reno(COLUMN)65(COLUMN)37 Richmond(COLUMN)75(COLUMN)64 St. Louis(COLUMN)84(COLUMN)66 St. Prbg.-Tampa(COLUMN)85(COLUMN)69 Salt Lake City(COLUMN)59(COLUMN)41 San Antonio(COLUMN)84(COLUMN)71 San Diego(COLUMN)67(COLUMN)60 San Francisco(COLUMN)60(COLUMN)50 San Juan, P.R.(COLUMN)86(COLUMN)72 St. Ste. Marie(COLUMN)65(COLUMN)44 Seattle(COLUMN)55(COLUMN)43 Shreveport(COLUMN)84(COLUMN)65 Sioux Falls(COLUMN)71(COLUMN)46 Spokane(COLUMN)51(COLUMN)34 Syracuse(COLUMN)70(COLUMN)53 Topeka(COLUMN)71(COLUMN)66 Tucson(COLUMN)82(COLUMN)59 Tulsa(COLUMN)83(COLUMN)71 Washington(COLUMN)67(COLUMN)65 Wichita(COLUMN)84(COLUMN)62(END TABLE) Temperatures Abroad Yesterday(TABLE) City(COLUMN)Weather(COLUMN)Time(COLUMN)Temp. Aberdeen(COLUMN)rain(COLUMN)1 p.m.(COLUMN)46 Amsterdam(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)50 Ankara(COLUMN)pt. cldy.(COLUMN)3 p.m.(COLUMN)57 Athens(COLUMN)clear(COLUMN)2 p.m.(COLUMN)81 Auckland(COLUMN)clear(COLUMN)midnight(COLUMN)48 Berlin(COLUMN)pt. cldy.(COLUMN)1 p.m.(COLUMN)77 Birmingham(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)50 Brussels(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)48 Cairo(COLUMN)clear(COLUMN)2 p.m.(COLUMN)81 Casablanca(COLUMN)clear(COLUMN)noon(COLUMN)63 Copenhagen(COLUMN)clear(COLUMN)1 p.m.(COLUMN)68 Dublin(COLUMN)pt. cldy.(COLUMN)1 p.m.(COLUMN)52 Geneva(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)48 Hong Kong(COLUMN)clear(COLUMN)8 p.m.(COLUMN)82 Lisbon(COLUMN)clear(COLUMN)noon(COLUMN)64 London(COLUMN)rain(COLUMN)1 p.m.(COLUMN)48 Madrid(COLUMN)pt. cldy.(COLUMN)1 p.m.(COLUMN)59 Malta(COLUMN)clear(COLUMN)1 p.m.(COLUMN)72 Manila(COLUMN)pt. cldy.(COLUMN)8 p.m.(COLUMN)84 Moscow(COLUMN)clear(COLUMN)3 p.m.(COLUMN)64 New Delhi(COLUMN)clear(COLUMN)5 p.m.(COLUMN)90 Nice(COLUMN)pt. cldy.(COLUMN)1 p.m.(COLUMN)63 Oslo(COLUMN)clear(COLUMN)1 p.m.(COLUMN)72 Paris(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)48 Peking(COLUMN)cloudy(COLUMN)8 p.m.(COLUMN)66 Rome(COLUMN)clear(COLUMN)1 p.m.(COLUMN)66 Saigon(COLUMN)clear(COLUMN)8 p.m.(COLUMN)84 Sofia(COLUMN)cloudy(COLUMN)2 p.m.(COLUMN)73 Stockholm(COLUMN)clear(COLUMN)1 p.m.(COLUMN)68 Sydney(COLUMN)cloudy(COLUMN)10 p.m.(COLUMN)66 Tel Aviv(COLUMN)clear(COLUMN)2 p.m.(COLUMN)73 Tokyo(COLUMN)cloudy(COLUMN)9 p.m.(COLUMN)57 Tunis(COLUMN)clear(COLUMN)1 p.m.(COLUMN)66 Vienna(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)73 Warsaw(COLUMN)clear(COLUMN)1 p.m.(COLUMN)79(END TABLE) Temperatures (Western Hemisphere)(TABLE) City(COLUMN)Weather(COLUMN)High(COLUMN)Low Acapulco(COLUMN)haze(COLUMN)88(COLUMN)73 Barbados(COLUMN)pt. cldy.(COLUMN)85(COLUMN)75 Bermuda(COLUMN)cloudy(COLUMN)77(COLUMN)67 Bogota(COLUMN)pt. cldy.(COLUMN)62(COLUMN)48 Calgary(COLUMN)cloudy(COLUMN)57(COLUMN)37 Cullacan(COLUMN)clear(COLUMN)91(COLUMN)62 Edmonton(COLUMN)rain(COLUMN)63(COLUMN)45 Havana(COLUMN)cloudy(COLUMN)86(COLUMN)72 Kingston(COLUMN)cloudy(COLUMN)86(COLUMN)77 Montego Bay(COLUMN)cloudy(COLUMN)86(COLUMN)73 Mexico City(COLUMN)haze(COLUMN)81(COLUMN)53 Monterrey(COLUMN)cloudy(COLUMN)82(COLUMN)68 Montreal(COLUMN)clear(COLUMN)61(COLUMN)41 Ottawa(COLUMN)clear(COLUMN)63(COLUMN)41 Regina(COLUMN)rain(COLUMN)73(COLUMN)45 St. Kitts(COLUMN)pt. cldy.(COLUMN)86(COLUMN)78 St. Thomas(COLUMN)cloudy(COLUMN)86(COLUMN)74 Toronto(COLUMN)cloudy(COLUMN)54(COLUMN)46 Vancouver(COLUMN)cloudy(COLUMN)55(COLUMN)43 Veracruz(COLUMN)haze(COLUMN)90(COLUMN)70 Winnipeg(COLUMN)rain(COLUMN)70(COLUMN)57(END TABLE)