Washington: Today - Sunny, high near 73, low in the mid 42s. The chance of rain is near zero today and 10 percent tonight. Wind will be from the northwest at less than 20 mph. Saturday - Increasingly cloudy, high near 70.

Maryland and Virginia: Today - Sunny, highs from the mid 50s to the low 70s. There is a chance of rain in western Virginia. Saturday - Sunny, highs from the 60s to the low 70s.

Lower Potomac and chesapeake Bay: Today - Fair with visibility of more than 5 miles. Wind will be from the northwest at less than 20 knots. Waves in unprotected waters will be up to 2 feet.

Extended Area Forecast for Sunday through Tuesday: Variably cloudy through the period. Chance of rain early on Sunday and again on Tuesday. Highs will be from the mids 50s to the mids 70s, low from the upper 30s to the 40s. Normal Washington temperatures for the period are a high of 68 and a low of 46.

West Virginia: Today - Sunny, highs from the upper 50s to the mid 60s, low in the 30s. Saturday - Partly cloudy, chance of showers, high from the mid to upper 50s.

The National Weather Forecast for today - Rain will extend from the northern half of California through Washington State and eastward through the northern and central Plateau, into portions of the northern and central Rockies and into the northern and central Plains. There is a chance of snow in higher elevations in the northern Rockies. Rain is also possible in parts of the southern Plateau, Michigan and from Lower Great Lakes into New England. There is a chance of snow in extreme northern New England. Skies over much of the remainder of the country will be sunny to mostly sunny. Temperatures will be mild in the southern Rockies, the southern half of the Plains, the middle Mississippi Valley and the southern and middle Atlantic Coast. Much of the remainder of the country will be cool.

Almanac Data for today: Sun rises 5:34 a.m., sets 6:44 p.m.; Moon rises 10:40 a.m., sets 12:18 a.m. Tides: high 12:23 a.m. and 11:30 p.m., low 7:19 a.m. and 7:53 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 p.m. to 3 p.m. period was 49 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 individual's 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 be near 4.3 feet today.

Washington data at 7 p.m. (EST) yesterday: Highest temperature since 7 a.m. yesterday, 80 degrees at 4:15 p.m. Lowest temperature since midnight, 56 degrees at 6:00 p.m. Excess of temperature since April 1, 90 degrees. Deficiency of temperature since Jan. 1, 173 degrees. Record high temperature for today. 91 degrees in 1960. Record low temperature for today, 24 degrees in 1950. Relative humidity: Maximum, 55 percent at 7 a.m. Minimum, 26 percent at 1 p.m. Deficiency of precipitation since April 1, 1 inch. Excess of precipitation since Jan. 1, 2.6 inches. Highest observed wind since 7 a.m. 18 miles per hour from the northwest at 6 p.m. Peak gust since 7 a.m., 31 miles per hour from the northwest at 5:37 p.m. Local Temps., Humidity(TABLE) Time(COLUMN)T.(COLUMN)H. 12 midnite(COLUMN)62(COLUMN)39 1 a.m.(COLUMN)62(COLUMN)39 2 a.m.(COLUMN)60(COLUMN)43 3 a.m.(COLUMN)58(COLUMN)49 4 a.m.(COLUMN)59(COLUMN)51 5 a.m.(COLUMN)58(COLUMN)47 6 a.m.(COLUMN)58(COLUMN)49 7 a.m.(COLUMN)57(COLUMN)55 8 a.m.(COLUMN)61(COLUMN)54 9 a.m.(COLUMN)63(COLUMN)54 10 a.m.(COLUMN)66(COLUMN)49 11 a.m.(COLUMN)69(COLUMN)46 12 noon(COLUMN)75(COLUMN)30 1 p.m.(COLUMN)76(COLUMN)26 2 p.m.(COLUMN)77(COLUMN)27 3 p.m.(COLUMN)78(COLUMN)27 4 p.m.(COLUMN)78(COLUMN)28 5 p.m.(COLUMN)78(COLUMN)28 6 p.m.(COLUMN)75(COLUMN)27 7 p.m.(COLUMN)73(COLUMN)26(END TABLE) Temperatures ending 7 a.m. (EST) yesterday:(TABLE) City(COLUMN)H.(COLUMN)L. Albany(COLUMN)50(COLUMN)37 Alburquerque(COLUMN)80(COLUMN)47 Amarillo(COLUMN)71(COLUMN)43 Anchorage(COLUMN)44(COLUMN)30 Asheville(COLUMN)70(COLUMN)51 Atlanta(COLUMN)73(COLUMN)52 Atlantic City(COLUMN)68(COLUMN)49 Austin(COLUMN)65(COLUMN)48 Baltimore(COLUMN)75(COLUMN)49 Billings(COLUMN)50(COLUMN)27 Birmingham(COLUMN)62(COLUMN)53 Bismark(COLUMN)43(COLUMN)28 Boise(COLUMN)57(COLUMN)34 Boston(COLUMN)61(COLUMN)45 Brownsville(COLUMN)70(COLUMN)51 Buffalo(COLUMN)58(COLUMN)40 Burington(COLUMN)47(COLUMN)41 Casper(COLUMN)51(COLUMN)20 Charleston, S.C.(COLUMN)70(COLUMN)65 Charlton, W.V.(COLUMN)71(COLUMN)51 Charlotte(COLUMN)74(COLUMN)52 Cheyenne(COLUMN)55(COLUMN)28 Chicago(COLUMN)67(COLUMN)38 Cincinnati(COLUMN)69(COLUMN)48 Clevland(COLUMN)70(COLUMN)49 Columbia, S.C.(COLUMN)77(COLUMN)58 Columbus, Ohio(COLUMN)69(COLUMN)50 Dal.-Ft. Worth(COLUMN)75(COLUMN)47 Dayton(COLUMN)70(COLUMN)45 Denver(COLUMN)61(COLUMN)34 Des Moines(COLUMN)65(COLUMN)35 Detroit(COLUMN)68(COLUMN)41 Duluth(COLUMN)47(COLUMN)27 El Paso(COLUMN)84(COLUMN)56 Fairbanks(COLUMN)43(COLUMN)27 Fargo(COLUMN)48(COLUMN)27 Flagstaff(COLUMN)65(COLUMN)38 Great Falls(COLUMN)50(COLUMN)23 Hartford(COLUMN)66(COLUMN)42 Helena(COLUMN)54(COLUMN)25 Honolulu(COLUMN)86(COLUMN)68 Houston(COLUMN)58(COLUMN)54 Indianapolis(COLUMN)73(COLUMN)44 Jackson, Miss.(COLUMN)60(COLUMN)52 Jacksonville(COLUMN)82(COLUMN)65 Jumeau(COLUMN)50(COLUMN)28 Kansas City(COLUMN)65(COLUMN)42 Las Vegas(COLUMN)87(COLUMN)65 Little Rock(COLUMN)72(COLUMN)49 Los Angeles(COLUMN)66(COLUMN)57 Louisville(COLUMN)71(COLUMN)52 Merrcilis(COLUMN)68(COLUMN)51 Miami Beach(COLUMN)79(COLUMN)75 Midiana-Odessa(COLUMN)82(COLUMN)46 Milwaukee(COLUMN)66(COLUMN)37 Mpis-St. Paul(COLUMN)53(COLUMN)51 Nashville(COLUMN)71(COLUMN)47 New Orleans(COLUMN)66(COLUMN)61 New York(COLUMN)71(COLUMN)54 Norfolk(COLUMN)70(COLUMN)56 North Plathe(COLUMN)60(COLUMN)26 Oklahoma City(COLUMN)76(COLUMN)51 Omatha(COLUMN)62(COLUMN)35 Orlando(COLUMN)90(COLUMN)71 Philadelphia(COLUMN)71(COLUMN)47 Phoenix(COLUMN)91(COLUMN)61 Pittsburgh(COLUMN)71(COLUMN)50 Portland, Maine(COLUMN)52(COLUMN)37 Portland, Ore.(COLUMN)62(COLUMN)40 Providence(COLUMN)62(COLUMN)41 Raleign(COLUMN)72(COLUMN)57 Rapid City(COLUMN)52(COLUMN)23 Reno(COLUMN)70(COLUMN)42 Richmond(COLUMN)75(COLUMN)55 St. Louis(COLUMN)75(COLUMN)41 St. Prog.-Tampa(COLUMN)86(COLUMN)74 Salt Lake City(COLUMN)59(COLUMN)38 San Antonio(COLUMN)61(COLUMN)44 San Diego(COLUMN)68(COLUMN)62 San Francisco(COLUMN)64(COLUMN)54 San Juan(COLUMN)87(COLUMN)70 St. Ste. Marie(COLUMN)36(COLUMN)33 Seattle(COLUMN)57(COLUMN)40 Shrevport(COLUMN)70(COLUMN)42 Sioux Falls(COLUMN)52(COLUMN)28 Spokama(COLUMN)52(COLUMN)29 Syracuse(COLUMN)60(COLUMN)46 Topeka(COLUMN)67(COLUMN)33 Tucson(COLUMN)84(COLUMN)56 Tulsa(COLUMN)80(COLUMN)46 Washington(COLUMN)74(COLUMN)56 Wichita(COLUMN)69(COLUMN)46(END TABLE) Temperatures Abroad Yesterday(TABLE) City(COLUMN)Weather(COLUMN)Time(COLUMN)Temp. Aberdeen(COLUMN)snow(COLUMN)1 p.m.(COLUMN)36 Amsterdam(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)41 Athens(COLUMN)cloudy(COLUMN)2 p.m.(COLUMN)67 Berlin(COLUMN)clear(COLUMN)1 p.m.(COLUMN)52 Birmingham(COLUMN)rain(COLUMN)1 p.m.(COLUMN)37 Brussels(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)43 Cairo(COLUMN)cloudy(COLUMN)2 p.m.(COLUMN)27 Casablanca(COLUMN)pt. cldy.(COLUMN)noon(COLUMN)59 Cooenhagen(COLUMN)clear(COLUMN)1 p.m.(COLUMN)43 Dublin(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)50 Geneva(COLUMN)clear(COLUMN)1 p.m.(COLUMN)48 Hong Kong(COLUMN)cloudy(COLUMN)8 p.m.(COLUMN)73 Lisbon(COLUMN)pt. cldy.(COLUMN)noon(COLUMN)59 London(COLUMN)rain(COLUMN)1 p.m.(COLUMN)37 Madrid(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)48 Malta(COLUMN)pt. cldy.(COLUMN)1 p.m.(COLUMN)66 Manila(COLUMN)clear(COLUMN)8 p.m.(COLUMN)86 Moscow(COLUMN)cloudy(COLUMN)3 p.m.(COLUMN)55 New Delhi(COLUMN)clear(COLUMN)5 p.m.(COLUMN)100 Nice(COLUMN)clear(COLUMN)1 p.m.(COLUMN)55 Oslo(COLUMN)clear(COLUMN)1 p.m.(COLUMN)43 Paris(COLUMN)pt. cldy.(COLUMN)1 p.m.(COLUMN)45 Peking(COLUMN)clear(COLUMN)8 p.m.(COLUMN)63 Rome(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)61 Saigon(COLUMN)cloudy(COLUMN)8 p.m.(COLUMN)84 Sofia(COLUMN)cloudy(COLUMN)2 p.m.(COLUMN)59 Stockholm(COLUMN)pt. cldy.(COLUMN)1 p.m.(COLUMN)43 Sydney(COLUMN)cloudy(COLUMN)10 p.m.(COLUMN)63 Tel Aviv(COLUMN)clear(COLUMN)2 p.m.(COLUMN)77 Tokyo(COLUMN)cloudy(COLUMN)9 p.m.(COLUMN)52 Tunis(COLUMN)pt. cldy.(COLUMN)1 p.m.(COLUMN)59 Vienna(COLUMN)snow(COLUMN)1 p.m.(COLUMN)36 Warsaw(COLUMN)rain(COLUMN)1 p.m.(COLUMN)34(END TABLE) Temperatures (Western Hemisphere)(TABLE) City(COLUMN)Weather(COLUMN)High(COLUMN)Low Acapulco(COLUMN)clear(COLUMN)88(COLUMN)75 Barbados(COLUMN)fair(COLUMN)86(COLUMN)77 Bermuda(COLUMN)cloudy(COLUMN)71(COLUMN)65 Bogota(COLUMN)cloudy(COLUMN)66(COLUMN)54 Calgary(COLUMN)cloudy(COLUMN)43(COLUMN)27 Cudiacan(COLUMN)fair(COLUMN)90(COLUMN)63 Edmonton(COLUMN)snow(COLUMN)43(COLUMN)25 Havana(COLUMN)fair(COLUMN)90(COLUMN)68 Kingston(COLUMN)fair(COLUMN)88(COLUMN)75 Montego Bay(COLUMN)fair(COLUMN)86(COLUMN)72 Mexico City(COLUMN)clear(COLUMN)81(COLUMN)55 Monterrey(COLUMN)fair(COLUMN)82(COLUMN)51 Montreal(COLUMN)clear(COLUMN)43(COLUMN)34 Nassau(COLUMN)fair(COLUMN)82(COLUMN)73 Ottawa(COLUMN)pt. cldy(COLUMN)45(COLUMN)30 Regina(COLUMN)pt. cldy(COLUMN)36(COLUMN)27 St. Kitts(COLUMN)pt. cldy(COLUMN)86(COLUMN)76 St. Thomas(COLUMN)pt. cldy(COLUMN)83(COLUMN)75 Toronto(COLUMN)clear(COLUMN)61(COLUMN)41 Vancouver(COLUMN)pt. cldy(COLUMN)52(COLUMN)43 Verachuz(COLUMN)pt. cldy(COLUMN)73(COLUMN)68 Winnipeg(COLUMN)pt. cldy(COLUMN)32(COLUMN)25(END TABLE)