Washington: Today - Partly cloudy, high in the mid 80s, low near 70. The chance of rain is 10 per cent today and 20 per cent tonight. Wednesday - partly cloudy, high in the mid 80s.

Maryland and Virginia: Today - Partly cloudy, chance of an afternoon or evening thundershower, highs from the mid 70s to near 90, lows from the mid 50s to the low 70s. Wednesday - Partly cloudy, highs from the mid 70s to near 90.

Lower Potomac and Chesapeake Bay: Today - Partly cloudy with visibility of from 2 to 5 miles. WInd will be from the west at near 8 knots today, then variable at near 8 knots tonight. Waves in unprotected waters will be less than 2 feet.

Atlantic Ocean Beaches from Cape May through Delaware: Today and Wednesday - Partly cloudy, highs in the 80s. Water temperatures will be from the low to mid 70s.

Atlantic Ocean Beaches from Maryland to Cape Hatteras: Today and Wednesday - Partly cloudy, chance of thundershowers, highs from the low 80s to near 90. Water temperature will be from the mid 70s to near 80.

Extended Area Forecast for Thursday through Saturday: Warm and humid through the period with a chance of thundershowers on each day. Highs will be from the mid 80s to the low 90s, lows from the 60s to the low 70s. Normal Washington temperatures for the period are a high of 88 and a low of 69.

The National Weather Forecast for Today - Skies will be mostly cloudy over the eastern Great Lakes and the southeastern Atlantic and Gulf coasts. There is a chance of thunderstorms over the southeastern Atlantic coast, Florida and the Gulf coast, with a slight chance for them as far west as Texas and eastern South Dakota. There is a chance of thunderstorms as far as Texas and South Dakota, in addition to Florida. The remainder of the nation should have sunny skies. It will be hot again over the west and southeast into Texas. Pleasant temperatures will hold over the Dakotas and east through the Great Lakes to New England.

Almanac Data for today - Sun rises 6:10 a.m., sets 8:18 p.m.; moon rises 10:08 p.M., sets 9:40 a.m. Tides: High 11:05 a.m. and 11:37 p.m., low 5:27 a.m. and 5:50 p.m. High and low tides at the following locations can be obtained by substracting 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), Pollen count: 5 english plaintain (note: more than 7 or higher is considered undesirable.)

The Council of Governments' Air Quality Index for yesterday showed the high reading in the Washington area during the 2 p.m. to 3 p.m. period was 49 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 be near 2.8 feet. Local Temp., Humidity(TABLE) Time(COLUMN)T.(COLUMN)H. 12 mid.(COLUMN)78(COLUMN)77 1 a.m.(COLUMN)77(COLUMN)77 2 a.m.(COLUMN)76(COLUMN)79 3 a.m.(COLUMN)77(COLUMN)79 4 a.m.(COLUMN)76(COLUMN)82 5 a.m.(COLUMN)75(COLUMN)85 6 a.m.(COLUMN)75(COLUMN)82 7 a.m.(COLUMN)75(COLUMN)82 8 a.m.(COLUMN)77(COLUMN)79 9 a.m.(COLUMN)79(COLUMN)74 10 a.m.(COLUMN)80(COLUMN)72 11 a.m.(COLUMN)83(COLUMN)67 12 noon(COLUMN)84(COLUMN)68 1 p.m.(COLUMN)86(COLUMN)66 2 p.m.(COLUMN)87(COLUMN)64 3 p.m.(COLUMN)84(COLUMN)70 4 p.m.(COLUMN)(COLUMN) 5 p.m.(COLUMN)75(COLUMN)79 6 p.m.(COLUMN)76(COLUMN)79 7 p.m.(COLUMN)76(COLUMN)79 8 p.m.(COLUMN)76(COLUMN)82(END TABLE) Temperatures ending 8 a.m. (EDT) Yesterday(TABLE) City(COLUMN)H.(COLUMN)L. Albany(COLUMN)88(COLUMN)71 ALbuquerque(COLUMN)99(COLUMN)69 Amarillo(COLUMN)96(COLUMN)64 Anchorage(COLUMN)65(COLUMN)56 Asheville(COLUMN)88(COLUMN)63 Atlanta(COLUMN)89(COLUMN)70 Atlantic City(COLUMN)81(COLUMN)74 Austin(COLUMN)101(COLUMN)75 Baltimore(COLUMN)91(COLUMN)71 Billings(COLUMN)85(COLUMN)58 Birmingham(COLUMN)88(COLUMN)71 Bismarck(COLUMN)79(COLUMN)48 Boise(COLUMN)93(COLUMN)62 Boston(COLUMN)88(COLUMN)70 Brownsville(COLUMN)97(COLUMN)79 Buffalo(COLUMN)88(COLUMN)66 Burlington(COLUMN)81(COLUMN)71 Casper(COLUMN)83(COLUMN)49 Charleston, S.C.(COLUMN)91(COLUMN)76 Charleston, W.Va.(COLUMN)89(COLUMN)70 Charlotte(COLUMN)95(COLUMN)70 Cheyenne(COLUMN)75(COLUMN)50 Chicago(COLUMN)86(COLUMN)57 Cincinnati(COLUMN)90(COLUMN)65 Cleveland(COLUMN)87(COLUMN)63 Columbia, S.C.(COLUMN)90(COLUMN)68 Columbus(COLUMN)89(COLUMN)61 Dal.-Ft. Worth(COLUMN)24(COLUMN)40 Dayton(COLUMN)88(COLUMN)61 Denver(COLUMN)81(COLUMN)56 Des Moines(COLUMN)83(COLUMN)56 Detroit(COLUMN)90(COLUMN)62 Duluth(COLUMN)69(COLUMN)52 El Paso(COLUMN)99(COLUMN)72 Fairbanks(COLUMN)84(COLUMN)60 Fargo(COLUMN)76(COLUMN)52 Flagstaff(COLUMN)91(COLUMN)51 Great Falls(COLUMN)88(COLUMN)57 Hartford(COLUMN)90(COLUMN)66 Helena(COLUMN)88(COLUMN)52 Honolulu(COLUMN)88(COLUMN)77 Houston(COLUMN)98(COLUMN)80 Indianapolis(COLUMN)86(COLUMN)58 Jackson, Miss.(COLUMN)93(COLUMN)74 Jacksonville(COLUMN)90(COLUMN)74 Kansas City(COLUMN)88(COLUMN)58 Las Vegas(COLUMN)115(COLUMN)82 Little Rock(COLUMN)81(COLUMN)76 Los Angeles(COLUMN)88(COLUMN)70 Lousiville(COLUMN)88(COLUMN)70 Memphis(COLUMN)91(COLUMN)75 Miami Beach(COLUMN)88(COLUMN)82 Midland-Odessa(COLUMN)103(COLUMN)70 Milwaukee(COLUMN)81(COLUMN)59 Mpls.-St. Paul(COLUMN)75(COLUMN)51 Nashville(COLUMN)92(COLUMN)67 New Orleasn(COLUMN)96(COLUMN)77 New York(COLUMN)88(COLUMN)73 Norfolk(COLUMN)90(COLUMN)76 North Platte(COLUMN)79(COLUMN)50 Oklahoma City(COLUMN)93(COLUMN)68 Omaha(COLUMN)80(COLUMN)58 Orlando(COLUMN)91(COLUMN)73 Philadelphia(COLUMN)90(COLUMN)71 Phoenix(COLUMN)110(COLUMN)86 Pittsburgh(COLUMN)85(COLUMN)62 Portland, Maine(COLUMN)81(COLUMN)57 Portland, Ore.(COLUMN)92(COLUMN)63 Providence(COLUMN)84(COLUMN)69 Raleigh(COLUMN)95(COLUMN)70 Rapid City(COLUMN)83(COLUMN)54 Reno(COLUMN)98(COLUMN)54 Richmond(COLUMN)94(COLUMN)74 St. Louis(COLUMN)92(COLUMN)63 St. Prbg.-Tampa(COLUMN)88(COLUMN)79 Salt Lake City(COLUMN)90(COLUMN)57 San Antonio(COLUMN)98(COLUMN)77 San Diego(COLUMN)82(COLUMN)71 San Francisco(COLUMN)81(COLUMN)60 San Juan(COLUMN)85(COLUMN)75 St. Ste. Marie(COLUMN)79(COLUMN)50 Seattle(COLUMN)85(COLUMN)62 Shreveport(COLUMN)95(COLUMN)69 Sioux Falls(COLUMN)80(COLUMN)53 Spokane(COLUMN)90(COLUMN)61 Syracuse(COLUMN)88(COLUMN)68 Topeka(COLUMN)91(COLUMN)53 Tucson(COLUMN)101(COLUMN)75 Tulsa(COLUMN)95(COLUMN)67 Washington(COLUMN)90(COLUMN)74 Wichita(COLUMN)90(COLUMN)63(END TABLE) Temperatures Abroad Yesterday(TABLE) City(COLUMN)Weather(COLUMN)Time(COLUMN)Temp. Aberdeen(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)73 Amsterdam(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)63 Ankara(COLUMN)clear(COLUMN)3 p.m.(COLUMN)86 Athens(COLUMN)pt. cldy(COLUMN)2 p.m.(COLUMN)86 Auckland(COLUMN)clear(COLUMN)midnight(COLUMN)43 Berlin(COLUMN)pt. cldy(COLUMN)1 p.m.(COLUMN)72 Birmingham(COLUMN)clear(COLUMN)1 p.m.(COLUMN)70 Brussels(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)61 Cairo(COLUMN)clear(COLUMN)2 p.m.(COLUMN)99 Casablance(COLUMN)clear(COLUMN)noon(COLUMN)79 Copenhagen clear(COLUMN)1 p.m.(COLUMN)70 Dublin(COLUMN)pt. cldy(COLUMN)1 p.m.(COLUMN)72 Geneva(COLUMN)clear(COLUMN)1 p.m.(COLUMN)66 Hong Kong(COLUMN)cloudy(COLUMN)8 p.m.(COLUMN)86 Lisbon(COLUMN)clear(COLUMN)noon(COLUMN)86 London(COLUMN)pt. cldy(COLUMN)1 p.m.(COLUMN)75 Madrid(COLUMN)clear(COLUMN)1 p.m.(COLUMN)79 Malta(COLUMN)clear(COLUMN)1 p.m.(COLUMN)79 Manila(COLUMN)cloudy(COLUMN)8 p.m.(COLUMN)77 Moscow(COLUMN)cloudy(COLUMN)3 p.m.(COLUMN)81 New Delhi(COLUMN)cloudy(COLUMN)5 p.m.(COLUMN)90 Nice(COLUMN)clear(COLUMN)1 p.m.(COLUMN)73 Oslo(COLUMN)pt. cldy(COLUMN)1 p.m.(COLUMN)73 Paris(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)63 Peking(COLUMN)cloudy(COLUMN)8 p.m.(COLUMN)84 Rome(COLUMN)clear(COLUMN)1 p.m.(COLUMN)75 Saigon(COLUMN)cloudy(COLUMN)8 p.m. Sofia(COLUMN)pt. cldy(COLUMN)2 p.m.(COLUMN)72 Stockholm clear(COLUMN)1 p.m.(COLUMN)73 Sydney(COLUMN)clear(COLUMN)10 p.m.(COLUMN)52 Tel Aviv(COLUMN)clear(COLUMN)2 p.m.(COLUMN)95 Tokyo(COLUMN)pt. cldy(COLUMN)9 p.m.(COLUMN)81 Tunis(COLUMN)clear(COLUMN)1 p.m.(COLUMN)84 Vienna(COLUMN)rain(COLUMN)1 p.m.(COLUMN)57 Warsaw(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)85(END TABLE) Temperatures (Western Hemisphere)(TABLE) City(COLUMN)Weather(COLUMN)High(COLUMN)Low Acapuko(COLUMN)fair(COLUMN)91(COLUMN)91 Bermuda(COLUMN)pt. cldy(COLUMN)86(COLUMN)79 Bogota(COLUMN)pt. cldy(COLUMN)64(COLUMN)53 Calgaray(COLUMN)clear(COLUMN)81(COLUMN)50 Culiacan(COLUMN)fair(COLUMN)95(COLUMN)75 Edmonton(COLUMN)clear(COLUMN)72(COLUMN)48 Havana(COLUMN)pt. cldy(COLUMN)89(COLUMN)75 Kingston(COLUMN)pt. cldy(COLUMN)92(COLUMN)77 Montego Bay(COLUMN)pt. cldy(COLUMN)89(COLUMN)75 Mexico City(COLUMN)pt. cldy(COLUMN)74(COLUMN)53 Monterrey(COLUMN)sunny(COLUMN)104(COLUMN)74 Montreal(COLUMN)pt. cldy(COLUMN)77(COLUMN)66 Nassau(COLUMN)pt. cldy(COLUMN)89(COLUMN)77 Ottawa(COLUMN)cloudy(COLUMN)81(COLUMN)63 Regina(COLUMN)fog(COLUMN)77(COLUMN)48 St. Thomas(COLUMN)pt. cldy(COLUMN)91(COLUMN)73 Toronto(COLUMN)pt. cldy(COLUMN)91(COLUMN)73 Vancouver(COLUMN)clear(COLUMN)77(COLUMN)59 Veracruz(COLUMN)pt. cldy(COLUMN)90(COLUMN)75(END TABLE)