Washington: Today - Partly cloudy and humid with a chance of showers or thundershowers. Highs will be in the mid 80s, lows in the low 70s. Chance of rain 60 percent today and 30 percent tonight. Winds will be southwesterly at 10 mph.Saturday - Partly cloudy, high in 80s.

Maryland and Virginia: Today - Partly cloudy and humid with a chance of afternoon showers east of the mountains. Highs will be in the 80s, lows in the 60s.

Lower Potomac and Chesapeake Bay: Today - Partly cloudy, visibility less than five miles at times. Winds will be southwesterly at 18 knots. Waves in unprotected waters will be one foot.

Atlantic Ocean Beaches from New Jersey to North Carolina: Today - Warm and humid with thundershowers likely, high in 80s. Saturday - Partly cloudy with chance of showers, high in 80s. Water temperatures; upper 60s to low 70s.

Extended Area Outlook for Sunday through Tuesday: Partly cloudy and warm through the period, with a chance of afternoon or evening thundershowers on Sunday and Monday. Highs will average in the mid to upper 80s, with lows mostly in the 60s. Normal Washington temperatures for the period will be a high of 88 and a low 69.

West Virginia: Today - Partly cloudy with a chance of showers or thunderstorms. Highs will be from the mid 70s to the low 80s, lows in the low 60s. Saturday - Partly cloudy, highs from the upper 70s to the 80s.

The National Weather Forecast for today - Showers and thundershowers will extend from the lower Mississippi Valley, the Ohio Valley, and lower Great Lakes to the Atlantic Coast. Most of the remainder of the country can expect sunny to mostly sunny skies. Temperatures throughout the nation will continue warm to hot.

Almanac Data for today: The sun rises 5:54 a.m., sets 8:33 p.m.; moon rises 2:45 p.m., sets 1:09 a.m. Tides: high 2:57 a.m. and 3:16 p.m., low 10:04 a.m. and 9:58 p.m. High and low tides at the following locations may be obtained by subtracting the hours indicated from the hours above: Annapolis (3 1/4), Bloody Point Lighthouse (4 1/2), Deale, Md. (4 1/2), Colonial Beach (5 1/4), Norfolk (1), Virginia Beach (3/4), Solomons Island (6 1/4), Point Lookout (7).

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 75 for the pollutant, photochemical oxidants. Index values between 50 and 99 indicate unhealthy air quality. When the index exceeds 100 the air is considered very unhealthy and individuals with lung, heart and eye ailments are urged to restrict their activity. The forecast for today indicates that the air quality will improve.

The National Weather Service forecasts the Potomac River Stage at Little Falls should fall to 3.8.

Lower Potomac and Chesapeake Bay: Today - Partly cloudy, visibility less than five miles at times. Winds will be southwesterly at 18 feet today. Local Temps., Humidity(TABLE) Time(COLUMN)T.(COLUMN)H. 12 midnight(COLUMN)68(COLUMN)70 1 a.m.(COLUMN)67(COLUMN)70 2 a.m.(COLUMN)66(COLUMN)73 3 a.m.(COLUMN)65(COLUMN)73 4 a.m.(COLUMN)64(COLUMN)81 5 a.m.(COLUMN)63(COLUMN)84 6 a.m.(COLUMN)63(COLUMN)84 7 a.m.(COLUMN)63(COLUMN)87 8 a.m.(COLUMN)67(COLUMN)76 9 a.m.(COLUMN)71(COLUMN)64 10 a.m.(COLUMN)74(COLUMN)58 11 a.m.(COLUMN)76(COLUMN)58 12 noon(COLUMN)80(COLUMN)51 1 p.m.(COLUMN)81(COLUMN)49 2 p.m.(COLUMN)83(COLUMN)48 3 p.m.(COLUMN)84(COLUMN)46 4 p.m.(COLUMN)84(COLUMN)48 5 p.m.(COLUMN)83(COLUMN)51 6 p.m.(COLUMN)83(COLUMN)53 7 p.m.(COLUMN)81(COLUMN)58(END TABLE) Temperatures ending 8 a.m. (EDT) yesterday:(TABLE) City(COLUMN)H.(COLUMN)L. Albany(COLUMN) 82(COLUMN)49 Albuquerque(COLUMN) 98(COLUMN)70 Amarillo(COLUMN) 97(COLUMN)70 Anchorage(COLUMN) 60(COLUMN)55 Asheville(COLUMN) 79(COLUMN)61 Atlanta(COLUMN) 80(COLUMN)68 Atlantic City(COLUMN) 73(COLUMN)60 Austin(COLUMN) 99(COLUMN)77 Baltimore(COLUMN) 82(COLUMN)55 Billings(COLUMN) 74(COLUMN)53 Birmingham(COLUMN) 92(COLUMN)75 Bismarck(COLUMN) 76(COLUMN)50 Boise(COLUMN) 89(COLUMN)56 Boston(COLUMN) 82(COLUMN)66 Brownsville(COLUMN) 97(COLUMN)77 Buffalo(COLUMN) 72(COLUMN)56 Burlington(COLUMN) 81(COLUMN)53 Casper(COLUMN) 85(COLUMN)50 Charleston, S.C.(COLUMN) 83(COLUMN)72 Charleston, W.Va.(COLUMN) 79(COLUMN)58 Charlotte(COLUMN) 82(COLUMN)65 Cheyenne(COLUMN) 89(COLUMN)55 Chicago(COLUMN) 77(COLUMN)67 Cincinnati(COLUMN) 78(COLUMN)66 Cleveland(COLUMN) 80(COLUMN)59 Columbia, S.C.(COLUMN) 87(COLUMN)62 Columbus(COLUMN) 78(COLUMN)63 Dal.-Ft. Worth(COLUMN)100(COLUMN)79 Dayton(COLUMN) 79(COLUMN)63 Denver(COLUMN) 95(COLUMN)61 Des Moines(COLUMN) 83(COLUMN)69 Detroit(COLUMN) 77(COLUMN)62 Duluth(COLUMN) 68(COLUMN)58 El Paso(COLUMN) 99(COLUMN)74 Fairbanks(COLUMN) 67(COLUMN)59 Fargo(COLUMN) 84(COLUMN)53 Flagstaff(COLUMN) 65(COLUMN)50 Great Falls(COLUMN) 75(COLUMN)53 Hartford(COLUMN) 82(COLUMN)54 Helena(COLUMN) 76(COLUMN)49 Honolulu(COLUMN) 86(COLUMN)74 Houston(COLUMN) 92(COLUMN)79 Indianapolis(COLUMN) 81(COLUMN)59 Jackson, Miss.(COLUMN) 94(COLUMN)77 Jacksonville(COLUMN) 87(COLUMN)70 Juneau(COLUMN) 56(COLUMN)49 Kansas City(COLUMN) 94(COLUMN)77 Las Vegas(COLUMN)105(COLUMN)75 Little Rock(COLUMN) 96(COLUMN)77 Los Angeles(COLUMN) 85(COLUMN)66 Louisville(COLUMN) 82(COLUMN)70 Memphis(COLUMN) 92(COLUMN)79 Miami Beach(COLUMN) 86(COLUMN)75 Midland-Odessa(COLUMN) 96(COLUMN)70 Milwaukee(COLUMN) 74(COLUMN)57 Mpls.-St. Paul(COLUMN) 78(COLUMN)63 Nashville(COLUMN) 87(COLUMN)72 New Orleans(COLUMN) 90(COLUMN)74 New York(COLUMN) 84(COLUMN)65 Norfolk(COLUMN) 76(COLUMN)54 North Platte(COLUMN) 96(COLUMN)61 Oklahoma City(COLUMN)101(COLUMN)77 Omaha(COLUMN) 94(COLUMN)67 Orlando(COLUMN) 90(COLUMN)74 Philadelphia(COLUMN) 82(COLUMN)60 Phoenix(COLUMN)109(COLUMN)88 Pittsburgh(COLUMN) 78(COLUMN)56 Portland, Maine(COLUMN) 84(COLUMN)52 Portland, Ore.(COLUMN) 84(COLUMN)60 Providence(COLUMN) 81(COLUMN)62 Raleigh(COLUMN) 83(COLUMN)56 Rapid City(COLUMN) 80(COLUMN)53 Reno(COLUMN) 88(COLUMN)59 Richmond(COLUMN) 83(COLUMN)54 St. Louis(COLUMN) 78(COLUMN)76 St. Prbg.-Tampa(COLUMN) 90(COLUMN)76 Salt Lake City(COLUMN) 95(COLUMN)59 San Antonio(COLUMN) 99(COLUMN)76 San Diego(COLUMN) 77(COLUMN)67 San Francisco(COLUMN) 61(COLUMN)52 San Juan(COLUMN) 88(COLUMN)76 St. Ste. Marie(COLUMN) 78(COLUMN)58 Seattle(COLUMN) 79(COLUMN)60 Shreveport(COLUMN) 99(COLUMN)74 Sioux Falls(COLUMN) 87(COLUMN)55 Spokane(COLUMN) 76(COLUMN)53 Syracuse(COLUMN) 82(COLUMN)53 Topeka(COLUMN) 92(COLUMN)72 Tucson(COLUMN) 98(COLUMN)79 Tulsa(COLUMN)102(COLUMN)80 Washington(COLUMN) 81(COLUMN)62 Wichita(COLUMN)105(COLUMN)81(END TABLE) Temperatures Abroad Yesterday(TABLE) City(COLUMN)Weather(COLUMN)Time(COLUMN)Temp. Aberdeen(COLUMN)cloudy(COLUMN) 1 p.m.(COLUMN)55 Amsterdam(COLUMN)clear(COLUMN) 1 p.m.(COLUMN)66 Ankara(COLUMN)clear(COLUMN) 3 p.m.(COLUMN)82 Athens(COLUMN)clear(COLUMN) 2 p.m.(COLUMN)99 Auckland(COLUMN)clear(COLUMN)12 a.m.(COLUMN)52 Berlin(COLUMN)clear(COLUMN) 1 p.m.(COLUMN)64 Birmingham(COLUMN)pt. cldy(COLUMN) 1 p.m.(COLUMN)70 Bonn(COLUMN)haze(COLUMN) 1 p.m.(COLUMN)68 Brussels(COLUMN)pt. cldy(COLUMN) 1 p.m.(COLUMN)68 Cairo(COLUMN)clear(COLUMN) 2 p.m.(COLUMN)79 Casablanca(COLUMN)clear(COLUMN)12 p.m.(COLUMN)72 Copenhagen(COLUMN)cloudy(COLUMN) 1 p.m.(COLUMN)57 Dublin(COLUMN)clear(COLUMN) 1 p.m.(COLUMN)68 Geneva(COLUMN)clear(COLUMN) 1 p.m.(COLUMN)75 Hong Kong(COLUMN)pt. cldy(COLUMN) 8 p.m.(COLUMN)84 London(COLUMN)haze(COLUMN) 1 p.m.(COLUMN)68 Madrid(COLUMN)clear(COLUMN) 1 p.m.(COLUMN)88 Malta(COLUMN)clear(COLUMN) 1 p.m.(COLUMN)93 Manila(COLUMN)clear(COLUMN) 8 p.m.(COLUMN)84 Moscow(COLUMN)cloudy(COLUMN) 3 p.m.(COLUMN)64 New Delhi(COLUMN)clear(COLUMN) 5 p.m.(COLUMN)93 Nice(COLUMN)clear(COLUMN) 1 p.m.(COLUMN)77 Oslo(COLUMN)cloudy(COLUMN) 1 p.m.(COLUMN)63 Paris(COLUMN)pt. cldy(COLUMN) 1 p.m.(COLUMN)75 Peking(COLUMN)cloudy(COLUMN) 8 p.m.(COLUMN)70 Rome(COLUMN)clear(COLUMN) 1 p.m.(COLUMN)88 Saigon(COLUMN)pt. cldy(COLUMN) 8 p.m.(COLUMN)84 Sofia(COLUMN)clear(COLUMN) 2 p.m.(COLUMN)86 Stockholm(COLUMN)cloudy(COLUMN) 1 p.m.(COLUMN)72 Sydney(COLUMN)clear(COLUMN)10 p.m.(COLUMN)46 Tokyo(COLUMN)cloudy(COLUMN) 9 p.m.(COLUMN)81 Tunis(COLUMN)clear(COLUMN) 1 p.m.(COLUMN)99 Vienna(COLUMN)pt. cldy(COLUMN) 1 p.m.(COLUMN)77 Warsaw(COLUMN)pt. cldy(COLUMN) 1 p.m.(COLUMN)68(END TABLE) Temperatures (Western Hemisphere)(TABLE) City(COLUMN)Weather(COLUMN)High(COLUMN)Low Acapulco(COLUMN)fair(COLUMN) 88(COLUMN)75 Barbados(COLUMN)pt. cldy(COLUMN) 82(COLUMN)77 Bermuda(COLUMN)storm(COLUMN) 85(COLUMN)73 Calgary(COLUMN)pt. cldy(COLUMN) 77(COLUMN)57 Culiacan(COLUMN)pt. cldy(COLUMN) 95(COLUMN)82 Edmonton(COLUMN)cloudy(COLUMN) 79(COLUMN)50 Montego Bay(COLUMN)fair(COLUMN) 88(COLUMN)72 Mexico City(COLUMN)fair(COLUMN) 75(COLUMN)54 Monterrey(COLUMN)fair(COLUMN)102(COLUMN)75 Montreal(COLUMN)pt. cldy(COLUMN) 82(COLUMN)57 Nassau(COLUMN)pt. cldy(COLUMN) 90(COLUMN)73 Ottawa(COLUMN)pt. cldy(COLUMN) 82(COLUMN)55 Regina(COLUMN)clear(COLUMN) 72(COLUMN)52 St. Kitts(COLUMN)fair(COLUMN) 89(COLUMN)75 St. Thomas(COLUMN)fair(COLUMN) 89(COLUMN)81 Toronto(COLUMN)clear(COLUMN) 82(COLUMN)55 Vancouver(COLUMN)clear(COLUMN) 73(COLUMN)55 Veracruz(COLUMN)pt. cldy(COLUMN)88(COLUMN)73 Winnipeg(COLUMN)cloudy(COLUMN) 82(COLUMN)54(END TABLE)