Washington: Today - Mostly sunny and warm, high near 90, low 65 to 70. The chance of rain is 10 percent today increasing to 50 percent tonight. Winds will become southwesterly at 10 to 15 mph. Tuesday - Variable cloudiness, chance of showers or thunderstorms, high in the 80s.

Maryland and Virginia: Today - Mostly sunny and warm, high near 90, low in the 60s. Tuesday - Variable cloudiness, chance of showers or thundershowers, high in the 80s.

Lower Potomac and Chesapeake Bay - Fair, with Increasing cloudiness and a chance of late evening showers or thundershowers. Visibility will be 5 miles or more diminishing to less than 1 mile in rain. Waves will average near 1 foot. Winds will be southerly increasing to 12 to 18 knots.

Extended Area Forecast for Wednesday through Friday - Sunny and pleasant early in the period becoming warmer and more humid Friday. Highs will average from the mid 70s to the 80s, lows will be in the 60s. Normal Washington temperatures are a high of 85 and a low of 65.

Atlantic Ocean Beaches from New Jersey to North Carolina: Today - Sunny, high in the 80s. Tuesday - Partly cloudy and cooler, with a chance of showers, high near 80. Water temperatures will range from the low to mid 60s in the north to near 70 in North Carolina.

The National Weather Forecast for today - Showers and thundershowers will extend from the Great Lakes and the Appalachians across the Tennessee Valley and the Gulf States from Louisiana through Florida. Showers will also continue in the Pacific Northwest. Temperatures will be mild or cool from the northern half of the Pacific Coast through the northern two-thirds of the Mississippi Valley and much of the lower Ohio Valley. Temperatures will be seasonably warm across the remainder of the nation.

The Council of Governments' Air Quailty Index for yesterday showed the high reading in the Washington area during the 1 p.m. period was 38 for the pollutant, photochemical oxidants. Index values between 25 and 49 indicate fair 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 remain about the same.

The National Weather Service forecasts the Potomac River Stage at Little Falls should remain near 3.6 feet today.

Almanac Data for today The sun rises 5:42 a.m., sets 8:34 p.m.; moon rises 11:54 a.m. Tides: high 1:02 a.m. and 1:14 p.m., low 7:55 a.m. and 8:18 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). Local Temps., Humidity(TABLE) Time(COLUMN)T.(COLUMN)H. 12 midnight(COLUMN)71(COLUMN)61 1 a.m.(COLUMN)70(COLUMN)66 2 a.m.(COLUMN)69(COLUMN)68 3 a.m.(COLUMN)68(COLUMN)70 4 a.m.(COLUMN)67(COLUMN)70 5 a.m.(COLUMN)65(COLUMN)75 6 a.m.(COLUMN)64(COLUMN)78 7 a.m.(COLUMN)65(COLUMN)75 8 a.m.(COLUMN)69(COLUMN)63 9 a.m.(COLUMN)73(COLUMN)55 10 a.m.(COLUMN)76(COLUMN)75 11 a.m.(COLUMN)78(COLUMN)52 12 noon(COLUMN)81(COLUMN)49 1 p.m..(COLUMN)83(COLUMN)48 2 p.m.(COLUMN)83(COLUMN)49 3 p.m.(COLUMN)85(COLUMN)48 4 p.m.(COLUMN)85(COLUMN)50 5 p.m.(COLUMN)85(COLUMN)50 6 p.m.(COLUMN)84(COLUMN)51 7 p.m.(COLUMN)83(COLUMN)51(END TABLE) Temperatures ending 8 a.m. (EDT) yesterday:(TABLE) City(COLUMN)H.(COLUMN)L. Albany(COLUMN)71(COLUMN)45 Albuquerque(COLUMN)95(COLUMN)58 Amarillo(COLUMN)91(COLUMN)66 Anchorage(COLUMN)65(COLUMN)45 Asheville(COLUMN)78(COLUMN)61 Atlanta(COLUMN)84(COLUMN)68 Atlantic City(COLUMN)74(COLUMN)59 Austin(COLUMN)90(COLUMN)71 Baltimore(COLUMN)82(COLUMN)59 Billings(COLUMN)65(COLUMN)45 Birmingham(COLUMN)85(COLUMN)66 Bismarck(COLUMN)73(COLUMN)49 Boise(COLUMN)59(COLUMN)41 Boston(COLUMN)74(COLUMN)58 Brownsville(COLUMN)92(COLUMN)78 Buffalo(COLUMN)72(COLUMN)59 Burlington, Vt.(COLUMN)68(COLUMN)52 Casper(COLUMN)78(COLUMN)47 Charleston, S.C.(COLUMN)82(COLUMN)74 Charleston, W.V.(COLUMN)81(COLUMN)60 Charlotte(COLUMN)81(COLUMN)66 Cheyenne(COLUMN)85(COLUMN)48 Chicago(COLUMN)84(COLUMN)64 Cincinnati(COLUMN)80(COLUMN)60 Cleveland(COLUMN)84(COLUMN)60 Columbia, S.C.(COLUMN)82(COLUMN)67 Columbus(COLUMN)78(COLUMN)59 Dal-Ft. Worth(COLUMN)92(COLUMN)71 Dayton(COLUMN)81(COLUMN)59 Denver(COLUMN)91(COLUMN)52 Des Moines(COLUMN)89(COLUMN)69 Detroit(COLUMN) 83(COLUMN)45 Duluth(COLUMN) 86(COLUMN)62 El Paso(COLUMN)101(COLUMN)77 Fairbanks(COLUMN) 73(COLUMN)53 Fargo(COLUMN) 87(COLUMN)55 Flagstaff(COLUMN) 75(COLUMN)53 Great Falls(COLUMN) 69(COLUMN)44 Hartford(COLUMN) 77(COLUMN)52 Helena(COLUMN) 66(COLUMN)49 Honolulu(COLUMN) 86(COLUMN)75 Houston(COLUMN) 86(COLUMN)76 Indianapolis(COLUMN) 82(COLUMN)60 Jackson(COLUMN) 88(COLUMN)68 Jacksonville(COLUMN) 92(COLUMN)74 Juneau(COLUMN)68(COLUMN)44 Kansas City(COLUMN) 85(COLUMN)68 Las Vegas(COLUMN)101(COLUMN)71 Little Rock(COLUMN) 83(COLUMN)65 Los Angeles(COLUMN) 76(COLUMN)62 Louisville(COLUMN) 84(COLUMN)60 Memphis(COLUMN) 84(COLUMN)63 Miami Beach(COLUMN) 86(COLUMN)81 Midland(COLUMN) 92(COLUMN)69 Milwaukee(COLUMN) 83(COLUMN)63 Mpls.-St. Paul(COLUMN) 93(COLUMN)72 Nashville(COLUMN) 83(COLUMN)60 New Orleans(COLUMN) 89(COLUMN)73 New York(COLUMN) 80(COLUMN)61 Norfolk(COLUMN) 78(COLUMN)57 North Platte(COLUMN) 90(COLUMN)58 Oklahoma City(COLUMN) 84(COLUMN)70 Omaha(COLUMN) 90(COLUMN)66 Orlando(COLUMN) 96(COLUMN)76 Philadelphia(COLUMN) 81(COLUMN)60 Phoenix(COLUMN)111(COLUMN)75 Pittsburgh(COLUMN) 79(COLUMN)58 Portland, Me.(COLUMN) 68(COLUMN)44 Portland, Or.(COLUMN) 63(COLUMN)56 Providence(COLUMN) 74(COLUMN)54 Raleigh(COLUMN) 84(COLUMN)59 Rapid City(COLUMN) 73(COLUMN)53 Reno(COLUMN) 75(COLUMN)37 Richmond(COLUMN) 83(COLUMN)54 St. Louis(COLUMN) 83(COLUMN)64 St. Prbg.-Tampa(COLUMN) 93(COLUMN)76 Salt Lake City(COLUMN) 75(COLUMN)44 San Antonio(COLUMN) 89(COLUMN)75 San Diego(COLUMN) 68(COLUMN)63 San Francisco(COLUMN) 62(COLUMN)55 San Juan(COLUMN) 89(COLUMN)75 St. Ste. Marie(COLUMN) 69(COLUMN)54 Seattle(COLUMN) 66(COLUMN)54 Shreveport(COLUMN) 87(COLUMN)66 Spokane(COLUMN) 65(COLUMN)44 Syracuse(COLUMN) 72(COLUMN)50 Topeka(COLUMN) 87(COLUMN)70 Tucson(COLUMN)105(COLUMN)73 Tulsa(COLUMN) 86(COLUMN)70 Washington(COLUMN) 84(COLUMN)64 Wichita(COLUMN) 90(COLUMN)69(END TABLE) Tempertures Abroad Yesterday(TABLE) City(COLUMN)Weather(COLUMN)Time(COLUMN)Temp. Aberdeen(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)59 Amsterdam(COLUMN)pt. cldy.(COLUMN)1 p.m.(COLUMN)57 Ankara(COLUMN)clear(COLUMN)3 p.m.(COLUMN)82 Athens(COLUMN)clear(COLUMN)2 p.m.(COLUMN)82 Auckland(COLUMN)clear(COLUMN)midnight(COLUMN)52 Berlin(COLUMN)rain(COLUMN)1 p.m.(COLUMN)55 Birmingham(COLUMN)clear(COLUMN)1 p.m.(COLUMN)66 Bonn(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)57 Brussels(COLUMN)clear(COLUMN)1 p.m.(COLUMN)59 Casablanca(COLUMN)cloudy(COLUMN)noon(COLUMN)68 Copenhagen(COLUMN)pt. cldy.(COLUMN)1 p.m.(COLUMN)61 Dublin(COLUMN)pt. cldy(COLUMN)1 p.m.(COLUMN)61 Geneva(COLUMN)clear(COLUMN)1 p.m.(COLUMN)66 Hong Kong(COLUMN)clear(COLUMN)8 p.m.(COLUMN)82 Jerusalem(COLUMN)clear(COLUMN)2 p.m.(COLUMN)95 Lisbon(COLUMN)cloudy(COLUMN)noon(COLUMN)66 London(COLUMN)clear(COLUMN)1 p.m.(COLUMN)68 Madrid(COLUMN)clear(COLUMN)1 p.m.(COLUMN)75 Malta(COLUMN)clear(COLUMN)1 p.m.(COLUMN)84 Manila(COLUMN)cloudy(COLUMN)8 p.m.(COLUMN)81 Moscow(COLUMN)cloudy(COLUMN)3 p.m.(COLUMN)63 New Delhi(COLUMN)clear(COLUMN)5 p.m.(COLUMN)91 Nice(COLUMN)clear(COLUMN)1 p.m.(COLUMN)73 Oslo(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)64 Paris(COLUMN)pt. cldy.(COLUMN)1 p.m.(COLUMN)61 Rome(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)81 Saigon(COLUMN)pt. cldy.(COLUMN)8 p.m.(COLUMN)84 Sofla(COLUMN)cloudy(COLUMN)2 p.m.(COLUMN)81 Stockholm(COLUMN)rain(COLUMN)1 p.m.(COLUMN)54 Sydney(COLUMN)cloudy(COLUMN)10 p.m.(COLUMN)50 Tokyo(COLUMN)cloudy(COLUMN)9 p.m.(COLUMN)75 Tunis(COLUMN)pt. cldy.(COLUMN)1 p.m.(COLUMN)75 Vienna(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)68 Warsaw(COLUMN)cloudy(COLUMN)10 p.m.(COLUMN)57(END TABLE) Temperatures (Western Hemisphere)(TABLE) City(COLUMN)Weather(COLUMN)High(COLUMN)Low Acapulco(COLUMN)fair(COLUMN)86(COLUMN)77 Barbados(COLUMN)rain(COLUMN)86(COLUMN)79 Bermuda(COLUMN)rain(COLUMN)79(COLUMN)74 Bogota(COLUMN)cloudy(COLUMN)59(COLUMN)41 Calgary(COLUMN)clear(COLUMN)57(COLUMN)37 Culiacan(COLUMN)fair(COLUMN)95(COLUMN)77 Edmonton(COLUMN)clear(COLUMN)63(COLUMN)37 Havana(COLUMN)pt. cldy.(COLUMN)91(COLUMN)77 Kingston(COLUMN)clear(COLUMN)89(COLUMN)79 Montego Bay(COLUMN)clear(COLUMN)84(COLUMN)75 Mexico City(COLUMN)fair(COLUMN)75(COLUMN)57 Monterrey(COLUMN)clear(COLUMN)91(COLUMN)73 Montreal(COLUMN)cloudy(COLUMN)64(COLUMN)52 Nassau(COLUMN)pt. cldy.(COLUMN)89(COLUMN)75 Ottawa(COLUMN)pt. cldy.(COLUMN)66(COLUMN)54 Regina(COLUMN)cloudy(COLUMN)59(COLUMN)50 St. Kitts(COLUMN)cloudy(COLUMN)86(COLUMN)77 St. Thomas(COLUMN)pt. cldy.(COLUMN)91(COLUMN)78 Vancouver(COLUMN)rain(COLUMN)66(COLUMN)52 Veracruz(COLUMN)fair(COLUMN)86(COLUMN)72(END TABLE)