Washington: Today - Partly cloudy and humid, highs in mid 80s, lows near 70. Chance of rain is 30 per cent today, 50 per cent tonight. Wednesday - Partly cloudy and humid, highs in mid 80s.

Maryland and Virginia: Today - Partly cloudy and humid with chance of afternoon and evening showers, highs in 80s, lows near 70. It should be slightly cooler in west. Wednesday - Partly cloudy and humid with chance of rain, highs in 80s.

Lower Potomac and Chesapeake Bay: Today - Chance of afternoon and evening showers with visibility from fair to poor. Winds should be northwesterly this morning, shifting to northeasterly this afternoon then becoming eastrerly tonight, at a speed of about 8 knots through tonight.

Extended Area Outlook: For Thursday through Saturday - Chance of ran Thursday followed by fair skies Friday and Saturday. Highs should average in mid 70s to mid 80s, lows from mid 50s to mid 60s through period. Washington's normal temperatures range for this time of year is from 82 to 63.

Atlantic Ocean Beaches from Cape May to Cape Hatteras: Today and Wednesday - Partly cloudy with chance of afternoon and evening showers, high in 80s. Water temperatures should range from low 70s in north to low 80s in south.

West Virginia: Today - Partly cloudy with chance of rain, highs in mid 70s to low 80s, lows in mid 50s to mid 60s. Wednesday - Partly cloudy with chance of rain, highs in mid 70s to low 80s.

Washington data at 8 p.m. (EDT) yesterday: Highest temperature since 8 a.m. yesterday, 87 degrees at 1:30 p.m. Lowest temperature since midnight, 74 degrees at 6:40 a.m. Excess of temperature since Sept. 1, 35 degrees. Excess fo temperature since Jan. 1, 371 degrees. Record high temperature for today, 98 degrees in 1954. Record low temperature for today, 47 degrees in 1909. Relative humidity: Maximum, 91 per cent at 5 a.m.; Minimum, 59 per cent at 1 p.m. 24 hour preciptation, trace. Deficiency of precipitation since Sept, 1, 62 inches. Deficiency of precipitation since Jan. 1, 7.03 inches. Highest observed wind since 8 a.m. 7 miles per hour from the south at 9:53 a.m. Peak, gust since 8 a.m.; 16 miles per hour from the east at 4:05 p.m.

The National Weather Forecast for Today - Scattered showers and thunderstoms are likely from the lower Mississippi Valley across the mid and south Atlantic Coast states through the Appalachians and in New England and Michigan. The rest of the nation will have mostly sunny skies. It will be mild over most of the Great Lakes region, the central high Plains and eastern Washington and seasonably hot over the desert southwest. Elsewhere, seasonal temperatures will prevail.

Almanac data for Tuesday, Sept. 6: Sun rises 6:41 a.m., sets 7:31 p.m.; moon rises 0:00 a.m., sets 2:54 p.m.

Tides: High 2:42 a.m. and 3:07 p.m., low 9:56 a.m. and 10:05 p.m. High and low tides at the following locations can be obtained by subtracting the hours indicated from the tides above: Annapolis (3 1/2); Bloody Point Lighthouse (4 1/2/; Deale, Md. (4 1/2; Colonial Beach (6); Norfolk (1 1/2); Virginia Beach (1); Solomons Island (6 1/2); Point Lookout (7).

Will remain about the same.

The National Weather Service forecasts the Potomac River stage at Little Falls should remain near 2.7 feet today.

The Council of Governments' Air Quality Index for yesterday showed the high reading in the Washington area during the 1 p.m. period was 100 for the pollutant, photochemical oxidants. Index values between 100 and 249 indicate very unhealthy air quality. When the index exceeds 100 the air is considered very unhealthy and individuals with lung, heart and eye aliments are urged to restrict their activity. The forecast for today indicates that the air quality Local Temp., Humidity(TABLE) Time.(COLUMN)T.(COLUMN)H 12 mid(COLUMN)77(COLUMN)79 1 a.m.(COLUMN)77(COLUMN)79 2 a.m.(COLUMN)76(COLUMN)85 3 a.m.(COLUMN)76(COLUMN)85 4 a.m.(COLUMN)75(COLUMN)87 5 a.m.(COLUMN)75(COLUMN)91 6 a.m.(COLUMN)75(COLUMN)88 7 a.m.(COLUMN)75(COLUMN)88 8 a.m.(COLUMN)77(COLUMN)82 9 a.m.(COLUMN)78(COLUMN)79 10 a.m.(COLUMN)78(COLUMN)79 11 a.m.(COLUMN)81(COLUMN)69 12 noon(COLUMN)84(COLUMN)63 1 p.m.(COLUMN)86(COLUMN)59 2 p.m.(COLUMN)86(COLUMN)59 3 p.m.(COLUMN)84(COLUMN)63 4 p.m.(COLUMN)85(COLUMN)61 5 p.m.(COLUMN)81(COLUMN)72 6 p.m.(COLUMN)84(COLUMN)65(END TABLE) Temperature ending 8 a.m. (EDT) yesterday.(TABLE) City.(COLUMN)H.(COLUMN)L Alabany(COLUMN) 78(COLUMN)59 Albuquerque(COLUMN) 87(COLUMN)61 Amarillo(COLUMN) 86(COLUMN)66 Anchorage(COLUMN) 65(COLUMN)52 Asheville(COLUMN) 83(COLUMN)64 Atlanta(COLUMN) 81(COLUMN)69 Atlantic City(COLUMN) 79(COLUMN)71 Austin(COLUMN) 99(COLUMN)74 Baltimore(COLUMN) 86$71 Billings(COLUMN) 86(COLUMN)58 Birmingham(COLUMN) 84(COLUMN)72 Bismack(COLUMN) 78(COLUMN)57 Boise(COLUMN) 93(COLUMN)56 Boston(COLUMN) 72(COLUMN)61 Brownsville(COLUMN) 96(COLUMN)73 Buffalo(COLUMN) 78(COLUMN)65 Burlington, Vt.(COLUMN) 75(COLUMN)59 Casper(COLUMN) 87(COLUMN)54 Charleston, S.C.(COLUMN) 80(COLUMN)74 Charleston, W. Va.(COLUMN) 87(COLUMN)66 Charlotte, N.C.(COLUMN) 92(COLUMN)71 Cheyenne(COLUMN) 79(COLUMN)52 Chicago(COLUMN) 86(COLUMN)69 Cincinnati(COLUMN) 86(COLUMN)71 Cleveland(COLUMN) 80(COLUMN)64 Columbia, S.C.(COLUMN) 85(COLUMN)70 Columbus, Ohio(COLUMN) 83(COLUMN)65 Dal,-Ft. Worth(COLUMN) 97(COLUMN)72 Dayton(COLUMN) 86(COLUMN)69 Denver(COLUMN) 82(COLUMN)57 Des Moines(COLUMN) 78(COLUMN)61 Detroit(COLUMN) 82(COLUMN)66 Duluth(COLUMN) 67(COLUMN)54 El Paso(COLUMN) 94(COLUMN)66 Fairbanks(COLUMN) 63(COLUMN)36 Fargo(COLUMN) 64(COLUMN)47 Flagstaff(COLUMN) 86(COLUMN)49 Great Falls(COLUMN) 88(COLUMN)59 Hartford(COLUMN) 80(COLUMN)62 Helena(COLUMN) 87(COLUMN)54 Honolulu(COLUMN) 88(COLUMN)76 Houston(COLUMN) 94(COLUMN)74 Indianapolis(COLUMN) 85(COLUMN)72 Jackson, Miss.(COLUMN) 88(COLUMN)73 Jacksonsville(COLUMN) 91(COLUMN)71 Juneau(COLUMN)67(COLUMN)52 Kansas City(COLUMN)76(COLUMN)69 Las Vegas(COLUMN)106(COLUMN)77 Little Rock(COLUMN)93(COLUMN)73 Los Angeles(COLUMN)87(COLUMN)65 Louisville(COLUMN)89(COLUMN)73 Memphis(COLUMN)96(COLUMN)76 Miami Beach(COLUMN)85(COLUMN)78 Midland(COLUMN)96(COLUMN)75 Milwaukee(COLUMN)33(COLUMN)59 Mpls.-St. Paul(COLUMN)75(COLUMN)54 Nashville(COLUMN)92(COLUMN)68 New Orleans(COLUMN)88(COLUMN)74 New York(COLUMN)83(COLUMN)69 Norfolk(COLUMN)89(COLUMN)72 North Platte(COLUMN)85(COLUMN)48 Oklahoma City(COLUMN)97(COLUMN)40 Omaha(COLUMN)77(COLUMN)59 Orlando(COLUMN)90(COLUMN)71 Philadelphia(COLUMN)83(COLUMN)69 Phoenix(COLUMN)109(COLUMN)88 Pittsburgh(COLUMN)79(COLUMN)61 Portland, Me.(COLUMN)71(COLUMN)51 Portland, Ore.(COLUMN)74(COLUMN)60 Providence(COLUMN)79(COLUMN)58 Raleigh(COLUMN)91(COLUMN)68 Rapid City(COLUMN)85(COLUMN)64 Reno(COLUMN)95(COLUMN)48 Richmond(COLUMN)88(COLUMN)70 St. Louis(COLUMN)90(COLUMN)70 St. Prbg-Tampa(COLUMN)89(COLUMN)74 Salt Lake City(COLUMN)91(COLUMN)60 San Antonio(COLUMN)98(COLUMN)73 San Diego(COLUMN)76(COLUMN)66 San Francisco(COLUMN)77(COLUMN)57 San Juan, P. R.(COLUMN)89(COLUMN)75 St. Ste. Marie(COLUMN)59(COLUMN)53 Seattle(COLUMN)75(COLUMN)55 Shreveport(COLUMN)95(COLUMN)71 Sioux Falls(COLUMN)78(COLUMN)53 Spokane(COLUMN)70(COLUMN)60 Syracuse(COLUMN)77(COLUMN)61 Topeka(COLUMN)76(COLUMN)68 Tucson(COLUMN)99(COLUMN)78 Tulsa(COLUMN)93(COLUMN)69 Washington(COLUMN)85(COLUMN)74 Wichita(COLUMN)79(COLUMN)69(END TABLE)(TABLE) City(COLUMN)Weather(COLUMN)Time(COLUMN)Temp. Aberdeen(COLUMN)pt. cldy(COLUMN)1 p.m.(COLUMN)63 Amsterdam(COLUMN)drizzle(COLUMN)1 p.m.(COLUMN)61 Ankara(COLUMN)clear(COLUMN)3 p.m.(COLUMN)82 Athens(COLUMN)rain(COLUMN)2 p.m.(COLUMN)82 Auckland(COLUMN)clear(COLUMN)midnight(COLUMN)48 Berlin(COLUMN)pt. cldy(COLUMN)1 p.m.(COLUMN)70 Birmingham(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)61 Brussels(COLUMN)pt. cldy(COLUMN)1 p.m.(COLUMN)66 Cairo(COLUMN)clear(COLUMN)2 p.m.(COLUMN)90 Casablanca(COLUMN)clear(COLUMN)noon(COLUMN)75 Copenhagen(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)63 Dublin(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)59 Geneva(COLUMN)clear(COLUMN)1 p.m.(COLUMN)68 Hong Kong(COLUMN)rain(COLUMN)8 p.m.(COLUMN)79 Lisbon(COLUMN)clear(COLUMN)noon(COLUMN)79 London(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)66 Madrid(COLUMN)clear(COLUMN)1 p.m.(COLUMN)86 Malta(COLUMN)clear(COLUMN)1 p.m.(COLUMN)82 Manila(COLUMN)cloudy(COLUMN)8 p.m.(COLUMN)81 Moscow(COLUMN)clear(COLUMN)3 p.m.(COLUMN)82 New Delhi(COLUMN)cloudy(COLUMN)5 p.m.(COLUMN)84 Nice(COLUMN)pt. cldy(COLUMN)1 p.m.(COLUMN)77 Oslo(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)59 Paris(COLUMN)pt. cldy(COLUMN)1 p. m.(COLUMN)70 Peking(COLUMN)pt. cldy(COLUMN)8 p.m.(COLUMN)72 Rome(COLUMN)clear(COLUMN)1 p.m.(COLUMN)81 Saigon(COLUMN)clear(COLUMN)8 p.m.(COLUMN)81 Sofia(COLUMN)pt. cldy(COLUMN)2 p.m.(COLUMN)73 Stockholm(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)61 Sydney(COLUMN)cloudy(COLUMN)10 p.m.(COLUMN)55 Tel Aviv(COLUMN)clear(COLUMN)2 p.m.(COLUMN)86 Tokyo(COLUMN)clear(COLUMN)9 p.m.(COLUMN)77 Tunis(COLUMN)pt. cldy(COLUMN)1 p.m.(COLUMN)81 Vienna(COLUMN)haze(COLUMN)1 p.m.(COLUMN)72 Warsaw(COLUMN)clear(COLUMN)1 p.m.(COLUMN)66(END TABLE)(TABLE) City(COLUMN)Weather(COLUMN)High(COLUMN)Low Acapulco(COLUMN)fair(COLUMN)92(COLUMN)79 Barbados(COLUMN)cloudy(COLUMN)87(COLUMN)73 Bermuda(COLUMN)pt. cldy(COLUMN)85(COLUMN)77 Bogota(COLUMN)fair(COLUMN)65(COLUMN)48 Calgary(COLUMN)pt. cldy(COLUMN)59(COLUMN)46 Edmonton(COLUMN)pt. cldy(COLUMN)55$(COLUMN)46 Havana(COLUMN)fair(COLUMN)87(COLUMN)- Kingston(COLUMN)pt. cldy(COLUMN)87(COLUMN)79 Montego Bay(COLUMN)clear(COLUMN)87(COLUMN)77 Mexico City(COLUMN)pt. cldy(COLUMN)75(COLUMN)55 Monterrey(COLUMN)clear(COLUMN)94(COLUMN)70 Montreal(COLUMN)cloudy(COLUMN)72(COLUMN)61 Nassau(COLUMN)rain(COLUMN)87(COLUMN)75 Ottawa(COLUMN)rain(COLUMN)73(COLUMN)57 Regina(COLUMN)pt. cldy(COLUMN)70(COLUMN)54 St. Kitts(COLUMN)cloudy(COLUMN)91(COLUMN)75 St. Thomas(COLUMN)90(COLUMN)78 Toronto(COLUMN)pt. cldy(COLUMN)73(COLUMN)61 Vancouver(COLUMN)clear(COLUMN)68(COLUMN)52 Veracruz(COLUMN)pt. cldy(COLUMN)87(COLUMN)73 Winnipeg(COLUMN)rain(COLUMN)61(COLUMN)46(END TABLE)