Washington: Today - Partly cloudy with a chance of showers or thunderstorms. Highs will be in the mid 80s, lows in the mid to upper 60s. Chance of rain is 30 percent today and 50 percent tonight. Winds will be northeasterly at 10 mph. Sunday - Partly cloudy, high 84 to 88.

Maryland and Virginia: Today - Mostly sunny, high in 80s, low in 60s. There will be a chance of thundershowers tonight and Sunday. Sunday - Partly cloudy, high near 90.

Lower Potomac and Chesapeake Bay: Today - Fair, visibility more than five miles. Winds will be northerly at 16 knots. Waves in unprotected waters will be 2 feet.

Atlantic Ocean Beaches from New Jersey to North Carolina: Today - Sunday highs from 70s to 80s. Sunday - Cloudy with showers and thunderstorms likely, high near 80. Water temperatures will range from the upper 60s in the north, to mid 70s in the south.

Extended Area Outlook for Monday through Wednesday: There will be warm and humid weather through the period. Skies will be mostly sunny with the exception of possible afternoon or evening thunderstorms. Highs will average in the 80s in the mountains and at the shore; but near 90 elsewhere. Lows will range from the mid 60s to the low 70s. Normal Washington temperatures for the period will be a high of 88 and a low 68.

The National Weather Forecast for today - Showers and thunderstorms will be scattered along the Gulf Coast from Texas across northern Florida and will be more general across central and southern Florida. Showers will be scattered across the Pacific northwest but will turn to thundershowers in Montana. There will be a good chance for thundershowers in the upper Mississippi Valley and upper Great Lakes but will be more scattered across the middle Mississippi Valley, the Ohio Valley, the Atlantic Coast states from North Carolina into the lower Great Lakes. Mild temperatures will continue across the northern and central plateau regions and the north Atlantic Coast states. It will be warm to hot across the rest of the nation with some very hot readings in western Missouri and the lower Ohio Valley.

Almanac Data for today: The sun rises 5:46 a.m., sets 7:37 p.m.; moon rises 2:02 a.m. sets 5:22 p.m. Tides: high 6:05 and 6:32 p.m., low 11:50 a.m. and 11:59 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 68 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 3.4 feet today. Local Temps., Humidity(TABLE) Time(COLUMN)T.(COLUMN)H. 12 m'night(COLUMN)74(COLUMN)82 1 a.m.(COLUMN)74(COLUMN)82 2 a.m.(COLUMN)73(COLUMN)85 3 a.m.(COLUMN)73(COLUMN)82 4 a.m.(COLUMN)72(COLUMN)85 5 a.m.(COLUMN)71(COLUMN)87 6 a.m.(COLUMN)71(COLUMN)87 7 a.m.(COLUMN)74(COLUMN)79 8 a.m.(COLUMN)77(COLUMN)71 9 a.m.(COLUMN)80(COLUMN)65 10 a.m.(COLUMN)82(COLUMN)61 11 a.m.(COLUMN)84(COLUMN)59 12 noon(COLUMN)86(COLUMN)57 1 p.m.(COLUMN)88(COLUMN)48 2 p.m.(COLUMN)90(COLUMN)46 3 p.m.(COLUMN)91(COLUMN)43 4 p.m.(COLUMN)91(COLUMN)44 5 p.m.(COLUMN)91(COLUMN)41 6 p.m.(COLUMN)90(COLUMN)42 7 p.m.(COLUMN)88(COLUMN)45(END TABLE) Temperatures ending 8 a.m. (EDT) yesterday:(TABLE) City(COLUMN)H.(COLUMN)L. Albany(COLUMN)85(COLUMN)56 Albuquerque(COLUMN)79(COLUMN)60 Amarillo(COLUMN)90(COLUMN)65 Anchorage(COLUMN)64(COLUMN)52 Asheville(COLUMN)92(COLUMN)62 Atlanta(COLUMN)96(COLUMN)71 Atlantic City(COLUMN)85(COLUMN)64 Austin(COLUMN)96(COLUMN)72 Baltimore(COLUMN)92(COLUMN)68 Billings(COLUMN)91(COLUMN)62 Birmingham(COLUMN)99(COLUMN)70 Bismarck(COLUMN)79(COLUMN)65 Boise(COLUMN)85(COLUMN)60 Boston(COLUMN)86(COLUMN)66 Brownsville(COLUMN)94(COLUMN)74 Buffalo(COLUMN)80(COLUMN)61 Burlington(COLUMN)80(COLUMN)55 Casper(COLUMN)86(COLUMN)63 Charleston, S.C.(COLUMN)95(COLUMN)80 Charleston, W.Va.(COLUMN)89(COLUMN)65 Charlotte(COLUMN)92(COLUMN)69 Cheyenne(COLUMN)79(COLUMN)57 Chicago(COLUMN)88(COLUMN)74 Cincinnati(COLUMN)91(COLUMN)72 Cleveland(COLUMN)86(COLUMN)67 Columbia, S.C.(COLUMN)97(COLUMN)72 Columbus(COLUMN)89(COLUMN)64 Dal.-Ft. Worth(COLUMN)98(COLUMN)75 Dayton(COLUMN)94(COLUMN)68 Denver(COLUMN)84(COLUMN)61 Des Moines(COLUMN)88(COLUMN)76 Detroit(COLUMN)91(COLUMN)68 Duluth(COLUMN)87(COLUMN)59 El Paso(COLUMN)80(COLUMN)65 Fairbanks(COLUMN)64(COLUMN)53 Fargo(COLUMN)87(COLUMN)68 Flagstaff(COLUMN)77(COLUMN)42 Great Falls(COLUMN)88(COLUMN)59 Hartford(COLUMN)92(COLUMN)63 Helena(COLUMN)92(COLUMN)60 Honolulu(COLUMN)85(COLUMN)74 Houston(COLUMN)90(COLUMN)75 Indianapolis(COLUMN)95(COLUMN)73 Jackson, Miss.(COLUMN)98(COLUMN)77 Jacksonville(COLUMN)97(COLUMN)73 Juneau(COLUMN)68(COLUMN)48 Kansas City(COLUMN)95(COLUMN)72 Las Vegas(COLUMN)99(COLUMN)70 Little Rock(COLUMN)95(COLUMN)77 Los Angeles(COLUMN)76(COLUMN)62 Louisville(COLUMN)96(COLUMN)72 Memphis(COLUMN)96(COLUMN)79 Miami Beach(COLUMN)87(COLUMN)80 Midland-Odessa(COLUMN)93(COLUMN)68 Milwaukee(COLUMN)83(COLUMN)69 Mpls.-St. Paul(COLUMN)89(COLUMN)70 Nashville(COLUMN)98(COLUMN)72 New Orleans(COLUMN)91(COLUMN)75 New York(COLUMN)89(COLUMN)70 Norfolk(COLUMN)88(COLUMN)70 North Platte(COLUMN)96(COLUMN)62 Oklahoma City(COLUMN)94(COLUMN)75 Omaha(COLUMN)82(COLUMN)75 Orlando(COLUMN)95(COLUMN)77 Philadelphia(COLUMN)91(COLUMN)69 Phoenix(COLUMN)104(COLUMN)76 Pittsburgh(COLUMN)87(COLUMN)66 Portland, Maine(COLUMN)83(COLUMN)59 Portland, Ore.(COLUMN)70(COLUMN)61 Providence(COLUMN)87(COLUMN)69 Raleigh(COLUMN)92(COLUMN)67 Rapid City(COLUMN)93(COLUMN)65 Reno(COLUMN)81(COLUMN)44 Richmond(COLUMN)92(COLUMN)69 St. Louis(COLUMN)95(COLUMN)74 St. Prbg.-Tampa(COLUMN)90(COLUMN)79 Salt Lake City(COLUMN)90(COLUMN)64 San Antonio(COLUMN)94(COLUMN)70 San Diego(COLUMN)73(COLUMN)64 San Francisco(COLUMN)67(COLUMN)55 San Juan(COLUMN)89(COLUMN)76 St. Ste. Marie(COLUMN)79(COLUMN)50 Seattle(COLUMN)67(COLUMN)59 Shreveport(COLUMN)98(COLUMN)72 Sioux Falls(COLUMN)91(COLUMN)72 Spokane(COLUMN)78(COLUMN)57 Syracuse(COLUMN)84(COLUMN)55 Topeka(COLUMN)92(COLUMN)71 Tucson(COLUMN)96(COLUMN)70 Tulsa(COLUMN)95(COLUMN)76 Washington(COLUMN)92(COLUMN)71 Wichita(COLUMN)98(COLUMN)72(END TABLE) Temperatures Abroad Yesterday(TABLE) City(COLUMN)Weather(COLUMN)Time(COLUMN)Temp. Aberdeen(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)57 Amsterdam(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)61 Ankara(COLUMN)pt. cldy.(COLUMN)3 p.m.(COLUMN)61 Athens(COLUMN)clear(COLUMN)2 p.m.(COLUMN)79 Auckland(COLUMN)clear(COLUMN)12 p.m.(COLUMN)43 Berlin(COLUMN)pt. cldy.(COLUMN)1 p.m.(COLUMN)75 Birmingham(COLUMN)pt. cldy.(COLUMN)1 p.m.(COLUMN)61 Bonn(COLUMN)rain(COLUMN)1 p.m.(COLUMN)59 Brussels(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)63 Cairo(COLUMN)clear(COLUMN)2 p.m.(COLUMN)84 Casablanca(COLUMN)cloudy(COLUMN)12 p.m.(COLUMN)73 Copenhagen(COLUMN)pt. cldy.(COLUMN)1 p.m.(COLUMN)66 Dublin(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)57 Geneva(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)72 Hong Kong(COLUMN)clear(COLUMN)8 p.m.(COLUMN)84 Jerusalem(COLUMN)clear(COLUMN)2 p.m.(COLUMN)73 Lisbon(COLUMN)clear(COLUMN)12 p.m.(COLUMN)72 London(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)72 Madrid(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)59 Malta(COLUMN)clear(COLUMN)1 p.m.(COLUMN)77 Manila(COLUMN)pt. cldy.(COLUMN)8 p.m.(COLUMN)79 Moscow(COLUMN)pt. cldy.(COLUMN)3 p.m.(COLUMN)73 New Delhi(COLUMN)clear(COLUMN)5 p.m.(COLUMN)91 Nice(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)68 Oslo(COLUMN)rain(COLUMN)1 p.m.(COLUMN)66 Paris(COLUMN)pt. cldy.(COLUMN)1 p.m.(COLUMN)73 Peking(COLUMN)storm(COLUMN)8 p.m.(COLUMN)73 Rome(COLUMN)clear(COLUMN)1 p.m.(COLUMN)77 Saigon(COLUMN)cloudy(COLUMN)8 p.m.(COLUMN)82 Sofia(COLUMN)cloudy(COLUMN)2 p.m.(COLUMN)59 Stockholm(COLUMN)pt. cldy.(COLUMN)1 p.m.(COLUMN)68 Sydney(COLUMN)rain(COLUMN)10 p.m.(COLUMN)55 Tokyo(COLUMN)clear(COLUMN)9 p.m.(COLUMN)75 Tunis(COLUMN)pt. cldy.(COLUMN)1 p.m.(COLUMN)84(END TABLE) Temperatures (Western Hemisphere)(TABLE) City(COLUMN)Weather(COLUMN)High(COLUMN)Low Acapulco(COLUMN)cloudy(COLUMN)91(COLUMN)73 Barbados(COLUMN)pt. cldy(COLUMN)84(COLUMN)77 Bermuda(COLUMN)pt. cldy(COLUMN)82(COLUMN)77 Bogota(COLUMN)cloudy(COLUMN)64(COLUMN)41 Calgary(COLUMN)clear(COLUMN)81(COLUMN)50 Edmonton(COLUMN)cloudy(COLUMN)86(COLUMN)61 Havana(COLUMN)pt. cldy(COLUMN)91(COLUMN)75 Kingston(COLUMN)fair(COLUMN)90(COLUMN)79 Montego Bay(COLUMN)fair(COLUMN)91(COLUMN)72 Mexico City(COLUMN)cloudy(COLUMN)73(COLUMN)55 Monterrey(COLUMN)clear(COLUMN)82(COLUMN)50 Nassau(COLUMN)pt. cldy(COLUMN)88(COLUMN)72 Ottawa(COLUMN)clear(COLUMN)82(COLUMN)52 Regina(COLUMN)pt. cldy(COLUMN)86(COLUMN)64 St. Kitts(COLUMN)pt. cldy(COLUMN)90(COLUMN)78 St. Thomas(COLUMN)pt. cldy(COLUMN)88(COLUMN)79 Toronto(COLUMN)clear(COLUMN)88(COLUMN)61 Vancouver(COLUMN)cloudy(COLUMN)68(COLUMN)59 Veracruz(COLUMN)pt. cldy(COLUMN)86(COLUMN)73 Winnipeg(COLUMN)cloudy(COLUMN)88(COLUMN)64(END TABLE)