Washington: Today - Cloudy and cooler with a chance of showers and thundershowers, high in the 80s, low in the 70s. The chance of rain is 50 percent through tonight. Winds will be from the north at 5 to 12 mph. Wednesday - Cloudy, with a chance of showers or thundershowers, high near 90.

Maryland and Virginia: Today - Cloudy and cooler with a chance of showers and thundershowers, high in the low 80s, low in the 60s to near 70. Wednesday - Cloudy with a chance of showers and thunderstorms, high in the 80s.

Extended Area Forecast for Thursday through Saturday - Partly cloudy, warm and humid through the period, with a chance of afternoon or evening showers and thundershowers Friday and Saturday. Highs will range from the upper 80s to mid 90s, lows from the mid 60s to mid 70s. Normal Washington temperatures are a high of 88 and a low of 69.

West Virginia: Today - Cloudy with a chance of thundershowers, highs from the mid 70s to low 80s, low in the 60s. Wednesday - Chance of showers and thundershowers, high in the upper 70s and 80s.

Lower Potomac and Chesapeake Bay - Mostly cloudy with a chance of showers and thunderstorms. Visibility will be 5 miles or more diminishing to less than 1 mile in rain. Winds will be southeasterly at 12 knots shifting to the south at 10 knots or less by evening. Waves will average near 2 feet.

Atlantic Ocean Beaches from New Jersey to North Carolina: Today and Wednesday - Mostly cloudy and cooler with a chance of showers and thunderstorms, highs from the upper 70s to low 80s. Water temperatures will range from the upper 60s in New Jersey to the upper 70s in North Carolina.

The National Weather Forecast for today - Showers will be scattered through the southern Rockies and portions of the southern Intermountain Region. Showers and occasional thunderstorms will reach from central Texas across the Gulf Coastal states, the Tennessee Valley, the Ohio Valley, the southern two thirds of the Appalachians and the Atlantic Coast from Florida to New England. Temperatures will be hot from Oregon over the northern Rockies, across the Plains from South Dakota through Kansas and into the Mississippi Valley from central Minnesota across Iowa. Seasonably mild temperatures will reach from inland portions of New England and the northern Atlantic Coastal states through the northern Appalachians. Temperatures elsewhere over the nation will remain generally warm.

The Council of Governments' Air Quality Index for yesterday showed the high reading in the Washington area during the 3 p.m. period was 65 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 remain near 3.2 feet today.

Almanac Data for today: The sun rises 6:03 a.m., sets 8:26 p.m.; moon rises 12:02 a.m., sets 12:18 p.m. Tides: high 1:12 p.m., low 7:39 p.m. and 7:59 p.m. High and low tides at the following locations may be obtained by subtracting the hours indicated from te 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). Local Temps., Humidity(TABLE) Time(COLUMN)T(COLUMN)H 12 mid.(COLUMN)88(COLUMN)66 1 a.m.(COLUMN)86(COLUMN)61 2 a.m.(COLUMN)84(COLUMN)61 3 a.m.(COLUMN)81(COLUMN)67 4 a.m.(COLUMN)80(COLUMN)69 5 a.m.(COLUMN)80(COLUMN)69 6 a.m.(COLUMN)79(COLUMN)72 7 a.m.(COLUMN)80(COLUMN)69 8 a.m.(COLUMN)82(COLUMN)67 9 a.m.(COLUMN)84(COLUMN)65 10 a.m.(COLUMN)86(COLUMN)63 11 a.m.(COLUMN)88(COLUMN)59 12 noon(COLUMN)87(COLUMN)61 1 p.m.(COLUMN)90(COLUMN)54 2 p.m.(COLUMN)88(COLUMN)56 3 p.m.(COLUMN)89(COLUMN)56 4 p.m.(COLUMN)89(COLUMN)54 5p.m.(COLUMN)89(COLUMN)54 6 p.m.(COLUMN)89(COLUMN)56 7 p.m.(COLUMN)88(COLUMN)58(END TABLE) Temperatures ending 8 a.m. (EDT) yesterday:(TABLE) City(COLUMN)H(COLUMN)L Albany(COLUMN)95(COLUMN)64 Albuquerque(COLUMN)86(COLUMN)64 Amarillo(COLUMN)84(COLUMN)64 Anchorage(COLUMN)68(COLUMN)57 Asheville(COLUMN)89(COLUMN)65 Atlanta(COLUMN)94(COLUMN)69 Atlantic City(COLUMN)88(COLUMN)72 Austin(COLUMN)94(COLUMN)72 Baltimore(COLUMN)100(COLUMN)75 Billings(COLUMN)91(COLUMN)64 Birmingham(COLUMN)93(COLUMN)73 Bismarck(COLUMN)84(COLUMN)59 Boise(COLUMN)104(COLUMN)60 Boston(COLUMN)99(COLUMN)71 Brownsville(COLUMN)97(COLUMN)74 Buffalo(COLUMN)83(COLUMN)57 Burlington, Vt.(COLUMN)91(COLUMN)58 Casper(COLUMN)85(COLUMN)55 Charleston, S.C.(COLUMN)91(COLUMN)79 Charleston, W. Va.(COLUMN)92(COLUMN)69 Charlotte(COLUMN)95(COLUMN)72 Cheyenne(COLUMN)81(COLUMN)54 Chicago(COLUMN)77(COLUMN)60 Cincinnati(COLUMN)93(COLUMN)73 Cleveland(COLUMN)89(COLUMN)61 Columbia, S.C.(COLUMN)94(COLUMN)73 Columbus(COLUMN)94(COLUMN)69 Dal.-Ft. Worth(COLUMN)86(COLUMN)72 Dayton(COLUMN)90(COLUMN)67 Denver(COLUMN)87(COLUMN)59 Des Moines(COLUMN)79(COLUMN)60 Detroit(COLUMN)80(COLUMN)59 Duluth(COLUMN)76(COLUMN)61 El Paso(COLUMN)86(COLUMN)70 Evansville(COLUMN)83(COLUMN)62 Fairbanks(COLUMN)73(COLUMN)50 Fargo(COLUMN)83(COLUMN)59 Flagstaff(COLUMN)87(COLUMN)54 Great Falls(COLUMN)94(COLUMN)61 Hartford(COLUMN)99(COLUMN)68 Helena(COLUMN)93(COLUMN)55 Honolulu(COLUMN)86(COLUMN)72 Houston(COLUMN)84(COLUMN)74 Indianapolis(COLUMN)88(COLUMN)70 Jackson(COLUMN)93(COLUMN)73 Jacksonville(COLUMN)90(COLUMN)72 Juneau(COLUMN)56(COLUMN)50 Kansas City(COLUMN)77(COLUMN)61 Las Vegas(COLUMN)110(COLUMN)83 Little Rock(COLUMN)93(COLUMN)69 Los Angeles(COLUMN)83(COLUMN)60 Louisville(COLUMN)95(COLUMN)71 Memphis(COLUMN)94(COLUMN)75 Miami Beach(COLUMN)85(COLUMN)81 Midland(COLUMN)87(COLUMN)66 Mllwaukee(COLUMN)71(COLUMN)57 Mpls.-St. Paul(COLUMN)78(COLUMN)57 Nashville(COLUMN)96(COLUMN)73 New Orleans(COLUMN)87(COLUMN)74 New York(COLUMN)80(COLUMN)00 Norfolk(COLUMN)96(COLUMN)77 North Platte(COLUMN)81(COLUMN)58 Oklahoma City(COLUMN)86(COLUMN)68 Omaha(COLUMN)78(COLUMN)61 Orlando(COLUMN)88(COLUMN)75 Philadelphia(COLUMN)99(COLUMN)77 Phoenix(COLUMN)103(COLUMN)89 Pittsburgh(COLUMN)93(COLUMN)69 Portland, Me.(COLUMN)96(COLUMN)64 Portland, Ore.(COLUMN)89(COLUMN)55 Providence(COLUMN)97(COLUMN)73 Raleigh(COLUMN)95(COLUMN)76 Rapid City(COLUMN)86(COLUMN)61 Reno(COLUMN)98(COLUMN)53 Richmond(COLUMN)100(COLUMN)75 St. Louis(COLUMN)79(COLUMN)66 St. Prbg.-Tampa(COLUMN)91(COLUMN)77 Salt Lake City(COLUMN)98(COLUMN)61 San Antonio(COLUMN)98(COLUMN)74 San Diego(COLUMN)78(COLUMN)69 San Francisco(COLUMN)60(COLUMN)52 San Juan(COLUMN)92(COLUMN)79 St. Ste. Marie(COLUMN)70(COLUMN)47 Seattle(COLUMN)84(COLUMN)54 Shreveport(COLUMN)97(COLUMN)70 Sioux Falls(COLUMN)79(COLUMN)62 Spokane(COLUMN)96(COLUMN)62 Syracuse(COLUMN)93(COLUMN)59 Topeka(COLUMN)78(COLUMN)52 Tucson(COLUMN)93(COLUMN)78 Tulsa(COLUMN)88(COLUMN)68 Washington(COLUMN)104(COLUMN)79 Wichita(COLUMN)83(COLUMN)62(END TABLE) Temperatures Abroad Yesterday(TABLE) City(COLUMN)Weather(COLUMN)Time(COLUMN)Temp Aberdeen(COLUMN)pt. cldy.(COLUMN)1 p.m.(COLUMN)64 Amsterdam(COLUMN)pt. cldy.(COLUMN)1 p.m.(COLUMN)70 Ankara(COLUMN)clear(COLUMN)3 p.m.(COLUMN)73 Athens(COLUMN)clear(COLUMN)2 p.m.(COLUMN)81 Auckland(COLUMN)rain(COLUMN)midnight(COLUMN)57 Berlin(COLUMN)pt. cldy.(COLUMN)1 p.m.(COLUMN)75 Birmingham(COLUMN)pt. cldy.(COLUMN)1 p.m.(COLUMN)64 Bonn(COLUMN)pt. cldy.(COLUMN)1 p.m.(COLUMN)77 Brussels(COLUMN)pt. cldy.(COLUMN)1 p.m.(COLUMN)73 Cairo(COLUMN)clear(COLUMN)2 p.m.(COLUMN)90 Casablanca(COLUMN)clear(COLUMN)noon(COLUMN)81 Copenhagen(COLUMN)pt. cldy.(COLUMN)1 p.m.(COLUMN)68 Dublin(COLUMN)pt. cldy.(COLUMN)1 p.m.(COLUMN)63 Geneva(COLUMN)clear(COLUMN)1 p.m.(COLUMN)75 Hong Kong(COLUMN)pt. cldy.(COLUMN)8 p.m.(COLUMN)84 Jerusalem(COLUMN)clear(COLUMN)2 p.m. Lisbon(COLUMN)clear(COLUMN)noon(COLUMN)88 London(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)64 Madrid(COLUMN)clear(COLUMN)1 p.m.(COLUMN)91 Malta(COLUMN)clear(COLUMN)1 p.m.(COLUMN)82 Manila(COLUMN)cloudy(COLUMN)8 p.m.(COLUMN)79 Moscow(COLUMN)rain(COLUMN)3 p.m.(COLUMN)59 New Delhi(COLUMN)cloudy(COLUMN)5 p.m.(COLUMN)86 Nice(COLUMN)clear(COLUMN)1 p.m.(COLUMN)75 Oslo(COLUMN)drizzle(COLUMN)1 p.m.(COLUMN)61 Paris(COLUMN)clear(COLUMN)1 p.m.(COLUMN)73 Peking(COLUMN)cloudy(COLUMN)8 p.m.(COLUMN)77 Rome(COLUMN)smoke(COLUMN)1 p.m.(COLUMN)63 Sofia(COLUMN)pt. cldy.(COLUMN)2 p.m.(COLUMN)66 Stockholm(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)68 Sydney(COLUMN)clear(COLUMN)10 p.m.(COLUMN)50 Tokyo(COLUMN)clear(COLUMN)9 p.m.(COLUMN)84 Tunis(COLUMN)clear(COLUMN)1 p.m.(COLUMN)82 Vienna(COLUMN)pt. cldy.(COLUMN)1 p.m.(COLUMN)70 Warsaw(COLUMN)clear(COLUMN)1 p.m.(COLUMN)54(END TABLE) Temperatures (Western Hemisphere)(TABLE) City(COLUMN)Weather(COLUMN)High(COLUMN)Low Acapulco(COLUMN)pt. cldy.(COLUMN)88(COLUMN)73 Barbados(COLUMN)pt. cldy.(COLUMN)86(COLUMN)79 Bermuda(COLUMN)fair(COLUMN)87(COLUMN)79 Bogota(COLUMN)cloudy(COLUMN)65(COLUMN)63 Calgary(COLUMN)clear(COLUMN)84(COLUMN)52 Edmonton(COLUMN)pt. cldy.(COLUMN)84(COLUMN)54 Havana(COLUMN)cloudy(COLUMN)90(COLUMN)75 Kingston(COLUMN)fair(COLUMN)92(COLUMN)83 Montego Bay(COLUMN)fair(COLUMN)86(COLUMN)73 Mexico City(COLUMN)cloudy(COLUMN)72(COLUMN)57 Monterrey(COLUMN)pt. cldy.(COLUMN)95(COLUMN)72 Montreal(COLUMN)clear(COLUMN)82(COLUMN)52 Ottawa(COLUMN)clear(COLUMN)84(COLUMN)55 Regina(COLUMN)clear(COLUMN)90(COLUMN)55 Toronto(COLUMN)pt. cldy.(COLUMN)82(COLUMN)54 Vancouver(COLUMN)clear(COLUMN)82(COLUMN)57 Winnipeg(COLUMN)cloudy(COLUMN)75(COLUMN)59(END TABLE)