Washington: Today - Mostly sunny, high in the 60s, low near 40. The chance of rain is near zero through tonight. Winds will be light and variable. Friday - Partly cloudy, high in the 60s.

Maryland and Virginia: Today - Mostly sunny, high in the low to mid 60s, low in the 30s to mid 40s. Friday - Partly cloudy, high in the 60s.

Extended Area Forecast for Saturday through Monday - Partly cloudy over the weekend, chance of rain on Monday. Highs will average from the mid 60s to the mid 70s, lows from the mid 40s to the 50s. Normal Washington temperatures are a high of 59 and a low of 40.

Lower Potomac and Chesapeake Bay - Partial clearing then becoming fair. Visibility will be 1 to 3 miles except less than 1 mile in morning fog. Winds will be variable at less than 10 knots. Waves will average near 1 foot.

The National Weather Forecast for Today - Rain is likely from Oregon into portions of the northern Plateau, and from the Dakotas into the upper Mississippi Valley. Snow will fall over the northern and central Rockies and Montana. Showers and thunderstorms will range across Florida. Skies will be mostly sunny from the Southern plateau and Rocky Mountain regions across the southern halves of the Plains and the Missisippi Valley to the East Coast from the Carolinas through New England.Mild temperatures are in store from the southern Plateau across western Texas, the central Plains and most of the middle and upper Mississippi Valley through the Great Lakes. Cool temperatures will prevail across the remainer of the nation.

Almanac Data for today: The sunrises 6:44 a.m., sets 5:00 p.m.; moon rises 2:13 p.m. sets 1:03 a.m. Tides: high 2:46 a.m. and 3:27 p.m. low 9:46 a.m. and 10:15 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), Solomans Island (6 1/4), Point Lookout (7).

The Council of Government's Air Quality Index for yesterday showed the high reading in the Washington area during the 3 p.m. period was 10 for the pollutant, photo-chemical oxidants. Index values between 0 and 24 indicate good 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 good.

The National Weather forecasts the Potomac River stage at Little Falls should remain near 2.9 feet today.

Washington data for yesterday: Highest temperature since midnight yesterday, 59 degrees at 3:20 p.m. Lowest temperature since midnight, 51 degrees at 5:40 a.m. Excess of temperature since Nov. 1, 50 degrees. Excess of temperature since Jan. 1, 144 degrees. Record high temperature for today, 77 degrees in 1975. Record low temperature for today, 26 degrees in 1976. Relative humidity: Maximum, 77 percent at 5 a.m.; minimum, 49 percent at 3 p.m. 24 hour precipitation, trace.

Deficiency of precipitation since Nov. 1, 70 inches. Deficiency of precipitation since Jan. 1, .40 inches. Highest observed wind since 7 a.m., 16 miles per hour from the north-northwest at 9 a.m. Peak gust since 7 a.m., 23 miles per hour from the north at 7:57 a.m. Local Temps., Humidity(TABLE) Time(COLUMN)T(COLUMN)H 12 m'night(COLUMN)56(COLUMN)67 1 a.m.(COLUMN)55(COLUMN)66 2 a.m.(COLUMN)55(COLUMN)66 3 a.m.(COLUMN)53(COLUMN)74 4 a.m.(COLUMN)53(COLUMN)69 5 a.m.(COLUMN)52(COLUMN)77 6 a.m.(COLUMN)51(COLUMN)77 7 a.m.(COLUMN)51(COLUMN)74 8 a.m.(COLUMN)52(COLUMN)69 9 a.m.(COLUMN)53(COLUMN)64 10 a.m.(COLUMN)53(COLUMN)61 11 a.m.(COLUMN)54(COLUMN)59 12 noon(COLUMN)56(COLUMN)55 1 p.m.(COLUMN)57(COLUMN)53 2 p.m.(COLUMN)58(COLUMN)49 3 p.m.(COLUMN)58(COLUMN)49 4 p.m.(COLUMN)58(COLUMN)51 5 p.m.(COLUMN)56(COLUMN)53 6 p.m.(COLUMN)55(COLUMN)55 7 p.m.(COLUMN)52(COLUMN)59(END TABLE) Temperatures ending 7 a.m. (EST) yesterday:(TABLE) City(COLUMN)H(COLUMN)L Albany(COLUMN)52(COLUMN)39 Albuquerque(COLUMN)69(COLUMN)37 Amarillo(COLUMN)63(COLUMN)40 Anchorage(COLUMN)34(COLUMN)23 Asheville(COLUMN)60(COLUMN)49 Atlanta(COLUMN)61(COLUMN)46 Atlantic City(COLUMN)63(COLUMN)49 Austin(COLUMN)63(COLUMN)40 Baltimore(COLUMN)66(COLUMN)51 Billings(COLUMN)65(COLUMN)52 Birmingham(COLUMN)68(COLUMN)45 Bismarck(COLUMN)66(COLUMN)40 Boise(COLUMN)52(COLUMN)31 Boston(COLUMN)59(COLUMN)44 Brownsville(COLUMN)69(COLUMN)51 Buffalo(COLUMN)47(COLUMN)28 Burlington, Vt.(COLUMN)49(COLUMN)30 Casper(COLUMN)64(COLUMN)49 Charleston, S.C.(COLUMN)72(COLUMN)68 Charleston, W.V.(COLUMN)53(COLUMN)43 Charlotte(COLUMN)73(COLUMN)58 Cheyenne(COLUMN)67(COLUMN)48 Chicago(COLUMN)52(COLUMN)36 Cincinnati(COLUMN)47(COLUMN)29 Cleveland(COLUMN)50(COLUMN)28 Columbia, S.C.(COLUMN)78(COLUMN)60 Columbus(COLUMN)47(COLUMN)27 Dal.-Ft. Worth(COLUMN)62(COLUMN)39 Dayton(COLUMN)46(COLUMN)07 Denver(COLUMN)73(COLUMN)40 Des Moines(COLUMN)57(COLUMN)37 Detroit(COLUMN)49(COLUMN)26 Duluth(COLUMN)49(COLUMN)41 El Paso(COLUMN)72(COLUMN)45 Evansville(COLUMN)53(COLUMN)29 Fairbanks(COLUMN)17(COLUMN)-02 Fargo(COLUMN)62(COLUMN)42 Flagstaff(COLUMN)59(COLUMN)24 Great Falls(COLUMN)65(COLUMN)54 Hartford(COLUMN)57(COLUMN)40 Helena(COLUMN)67(COLUMN)50 Honolulu(COLUMN)81(COLUMN)67 Houston(COLUMN)56(COLUMN)51 Indianapolis(COLUMN)51(COLUMN)28 Jackson(COLUMN)62(COLUMN)36 Jacksonville(COLUMN)78(COLUMN)63 Juneau(COLUMN)41(COLUMN)28 Kansas City(COLUMN)55(COLUMN)42 Las Vegas(COLUMN)81(COLUMN)50 Little Rock(COLUMN)59(COLUMN)38 Los Angeles(COLUMN)84(COLUMN)56 Louisville(COLUMN)49(COLUMN)35 Memphis(COLUMN)58(COLUMN)41 Miami Beach(COLUMN)80(COLUMN)73 Midland(COLUMN)58(COLUMN)42 Milwaukee(COLUMN)48(COLUMN)34 Mpls.-St. Paul(COLUMN)56(COLUMN)43 Nashville(COLUMN)58(COLUMN)40 New Orleans(COLUMN)67(COLUMN)53 New York(COLUMN)59(COLUMN)46 Norfolk(COLUMN)77(COLUMN)58 North Platte(COLUMN)70(COLUMN)32 Oklahoma City(COLUMN)58(COLUMN)37 Omaha(COLUMN)59(COLUMN)41 Orlando(COLUMN)83(COLUMN)67 Philadelphia(COLUMN)63(COLUMN)50 Phoenix(COLUMN)89(COLUMN)56 Pittsburgh(COLUMN)50(COLUMN)33 Portland, Me.(COLUMN)53(COLUMN)40 Portland, Ore.(COLUMN)59(COLUMN)51 Providence(COLUMN)62(COLUMN)47 Raleigh(COLUMN)76(COLUMN)55 Rapid City(COLUMN)73(COLUMN)43 Reno(COLUMN)66(COLUMN)27 Richmond(COLUMN)79(COLUMN)51 St. Louis(COLUMN)53(COLUMN)33 St. Prbg-Tampa(COLUMN)76(COLUMN)70 Salt Lake City(COLUMN)61(COLUMN)38 San Antonio(COLUMN)67(COLUMN)39 San Diego(COLUMN)76(COLUMN)58 San Francisco(COLUMN)77(COLUMN)59 San Juan(COLUMN)89(COLUMN)77 St. Ste. Marie(COLUMN)46(COLUMN)29 Seattle(COLUMN)59(COLUMN)50 Shreveport(COLUMN)58(COLUMN)38 Sioux Falls(COLUMN)63(COLUMN)47 Spokane(COLUMN)56(COLUMN)50 Syracuse(COLUMN)50(COLUMN)30 Topeka(COLUMN)56(COLUMN)39 Tucson(COLUMN)82(COLUMN)54 Tulsa(COLUMN)59(COLUMN)35 Washington(COLUMN)72(COLUMN)51 Wichita(COLUMN)56(COLUMN)38(END TABLE) Temperatures Abroad Yesterday(TABLE) City(COLUMN)Weather(COLUMN)Time(COLUMN)Temp. Aberdeen(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)52 Amsterdam(COLUMN)haze(COLUMN)1 p.m.(COLUMN)50 Ankara(COLUMN)pt. cldy.(COLUMN)3 p.m.(COLUMN)46 Athens(COLUMN)cloudy(COLUMN)2 p.m.(COLUMN)55 Auckland(COLUMN)pt. cldy.(COLUMN)m'nite(COLUMN)54 Berlin(COLUMN)haze(COLUMN)1 p.m.(COLUMN)43 Birmingham(COLUMN)pt. cldy.(COLUMN)1 p.m.(COLUMN)59 Bonn(COLUMN)clear(COLUMN)1 p.m.(COLUMN)45 Brussels(COLUMN)pt. cldy.(COLUMN)1 p.m.(COLUMN)52 Casablanca(COLUMN)pt. cldy.(COLUMN)noon(COLUMN)70 Copenhagen(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)43 Dublin(COLUMN)clear(COLUMN)1 p.m.(COLUMN)54 Geneva(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)43 Hong Kong(COLUMN)cloudy(COLUMN)8 p.m.(COLUMN)73 Jerusalem(COLUMN)pt. cldy.(COLUMN)2 p.m.(COLUMN)61 Lisbon(COLUMN)cloudy(COLUMN)noon(COLUMN)63 London(COLUMN)pt. cldy.(COLUMN)1 p.m.(COLUMN)63 Madrid(COLUMN)rain(COLUMN)1 p.m.(COLUMN)54 Malta(COLUMN)clear(COLUMN)1 p.m.(COLUMN)64 Manila(COLUMN)cloudy(COLUMN)8 p.m.(COLUMN)79 Moscow(COLUMN)cloudy(COLUMN)3 p.m.(COLUMN)34 New Delhi(COLUMN)clear(COLUMN)5 p.m.(COLUMN)81 Nice(COLUMN)clear(COLUMN)1 p.m.(COLUMN)63 Oslo(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)48 Paris(COLUMN)pt. cldy.(COLUMN)1 p.m.(COLUMN)55 Peking(COLUMN)clear(COLUMN)8 p.m.(COLUMN)45 Rome(COLUMN)clear(COLUMN)1 p.m.(COLUMN)61 Saigon(COLUMN)pt. cldy.(COLUMN)8 p.m.(COLUMN)84 Sofia(COLUMN)cloudy(COLUMN)2 p.m.(COLUMN)41 Stockholm(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)46 Tokyo(COLUMN)clear(COLUMN)9 p.m.(COLUMN)61 Tunis(COLUMN)pt. cldy.(COLUMN)1 p.m.(COLUMN)68 Vienna(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)39 Warsaw(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)43(END TABLE)(TABLE) City(COLUMN)Weather(COLUMN)High(COLUMN)Low Acapulco(COLUMN)fair(COLUMN)90(COLUMN)75 Barbados(COLUMN)pt. cldy(COLUMN)86(COLUMN)77 Bermuda(COLUMN)cloudy(COLUMN)82(COLUMN)74 Bogota(COLUMN)cloudy(COLUMN)66(COLUMN)35 Calgary(COLUMN)snow(COLUMN)64(COLUMN)28 Cutlecan(COLUMN)clear(COLUMN)95(COLUMN)62 Edmonton(COLUMN)pt. cldy.(COLUMN)52(COLUMN)32 Havana(COLUMN)cloudy(COLUMN)82(COLUMN)61 Kingston(COLUMN)cloudy(COLUMN)88(COLUMN)77 Montego Bay(COLUMN)pt. cldy.(COLUMN)86(COLUMN)73 Mexico City(COLUMN)fair(COLUMN)70(COLUMN)48 Monterrey(COLUMN)clear(COLUMN)70(COLUMN)47 Montreal(COLUMN)clear(COLUMN)45(COLUMN)25 Nassau(COLUMN)pt. cldy.(COLUMN)86(COLUMN)74 Ottawa(COLUMN)clear(COLUMN)43(COLUMN)23 Regina(COLUMN)clear(COLUMN)61(COLUMN)41 St. Kitts(COLUMN)pt. cldy.(COLUMN)88(COLUMN)74 Toronto(COLUMN)clear(COLUMN)46(COLUMN)23 Vancouver(COLUMN)cloudy(COLUMN)55(COLUMN)46 Vera Cruz(COLUMN)cloudy(COLUMN)81(COLUMN)71 Winnipeg(COLUMN)clear(COLUMN)57(COLUMN)43(END TABLE)