Washington: Today - Sunny, high in the mid 60s, low in the 40s. The chance of rain is near zero through tonight. Winds will be northwesterly at 10 to 15 mph. Sunday - Sunny, high in the 60s.

Maryland and Virginia: Today - Sunny, high in the 60s, low in upper 30s to mid 40s. Sunday - Sunny, high in the 60s.

Lower Potamac and Chesapeake Bay: Today - Fair will visibility of 5 miles or more. Winds will be from the north at 20 knots. Waves in unprotected waters will average 2 feet.

Extended Area Outlook for Monthe upper 60s, low in the 40s, with a chance of rain on Wednesday. Monday, high in the 70s, low in the 40s. Tuesday and Wednesday high in the upper 70s. Normal Washington temperatures for the period are a high of 65 and a low of 44.

West Virginia: Sunny, high in the upper 60s, low in the 40s. Sunday - Sunny, highs from the upper 70s.

The National Weather Forecast for today - Rain showers, with snow showers, in the higher mountain areas, will occur over Arizona, Utah, Idaho, northeastern Nevada and southern Idaho and across the south and central Rockies into the southwest parts of Montana. Scattered showers and some thundershowers are likely from southern and western Texas through the central Plains, South Dakota, the mid Mississippi Valley and southern Mennesota. Rain will also fall over North Dakota and be mixed with snow in northern Minnesota. A few snow flurries will dot Maine and New Hampshire. Most of the rest of the nation will have sunny or partly cloudy skies. It will be cooler over Arizona, Utah and the south and central Rockies. Cool temperature Pacific Coast and from the northern Plains across the Great Lakes region through Pennsylvania and New England. Elsewhere seasonably mild weather will prevail.

Almanac Data for today: Sun rises 5:35 a.m., sets 6:43 p.m.; moon rises 6:22 a.m., sets 7:52 p.m. Tides high 8:39 a.m. and 9:05 p.m., low 2:53 a.m. and 3:23 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 3/4): Norfolk (1); Virginia Beach (3 3/4); Solomons Island (6 1/4); Point Lockout (7).

The Council of Governments' Air Quality Index for yesterday showed the high reading in the Washington area during the 3 p.m. period was 40 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 improve.

The National Weather Service forcasts the Potamac River stage at Little Falls should remain near 4.9 feet today.

Washington data at 7 p.m. (EST) yesterday: Highest temperature since 7 a.m. yesterday, 77 degrees at 4:10 p.m. Lowest temperature since midnight, 47 degrees at 4:15 a.m. Excess of temperature since Apr. 1, 42 degrees. Deficiency of temperature since Jan. 1, 211 degrees. Record high temperature for today, 93 degrees in 1929. Record low temperature for today, 29 degrees in 1972. Relative humidity: Maximum, 86 percent at 6 a.m. Minimum, 23 percent at 6 p.m. 24 hour precipitation, .06 inches. Deficiency of precipitation since Apr. 1, .57 inch. Excess of precipitation since Jan. 7, 3.04 inches. Highest observed wind since 7 a.m., 21 miles per hour from the northwest at 11:53 a.m. peak gust since 7 a.m., 33 miles per hour from the northwest at 11:24 a.m. Local Temps., Humidity(TABLE) Time(COLUMN)T.(COLUMN)H. 12 midnight(COLUMN)49(COLUMN)68 1 a.m.(COLUMN)49(COLUMN)71 2 a.m.(COLUMN)49(COLUMN)80 3 a.m.(COLUMN)48(COLUMN)80 4 a.m.(COLUMN)48(COLUMN)80 5 a.m.(COLUMN)48(COLUMN)83 5 a.m.(COLUMN)48(COLUMN)83 6 a.m.(COLUMN)48(COLUMN)86 7 a.m.(COLUMN)49(COLUMN)80 8 a.m.(COLUMN)50(COLUMN)83 9 a.m.(COLUMN)54(COLUMN)77 10 a.m.(COLUMN)61(COLUMN)62 11 a.m.(COLUMN)66(COLUMN)56 12 noon(COLUMN)70(COLUMN)36 7 p.m.(COLUMN)71(COLUMN)36 2 p.m.(COLUMN)74(COLUMN)27 3 p.m.(COLUMN)74(COLUMN)27 4 p.m.(COLUMN)76(COLUMN)26 5 p.m.(COLUMN)76(COLUMN)24 6 p.m.(COLUMN)76(COLUMN)23 7 p.m.(COLUMN)73(COLUMN)24(END TABLE) Temperatures ending 7 a.m. (EST) yesterday:(TABLE) City(COLUMN)H.(COLUMN)L. Albany(COLUMN)52(COLUMN)33 Albuquerque(COLUMN)77(COLUMN)42 Amarillo(COLUMN)83(COLUMN)53 Anchorage(COLUMN)43(COLUMN)32 Asheville(COLUMN)78(COLUMN)60 Atlanta(COLUMN)76(COLUMN)56 Atlantic City(COLUMN)52(COLUMN)47 Austin(COLUMN)83(COLUMN)66 Baltimore(COLUMN)54(COLUMN)45 Billings(COLUMN)55(COLUMN)34 Birmingham(COLUMN)77(COLUMN)50 Bismarck(COLUMN)58(COLUMN)30 Boise(COLUMN)54(COLUMN)40 Boston(COLUMN)58(COLUMN) - Brownsville(COLUMN)85(COLUMN)70 Buffalo(COLUMN)48(COLUMN)41 Burlington, Vt.(COLUMN)41(COLUMN)25 Casper(COLUMN)63(COLUMN)37 Charleston, W. V.(COLUMN)84(COLUMN)53 Charlotte(COLUMN)80(COLUMN)60 Cheyenne(COLUMN)65(COLUMN)35 Chicago(COLUMN)65(COLUMN)42 Cincinnati(COLUMN)71(COLUMN)38 Cleveland(COLUMN)57(COLUMN)41 Columbia, S. C.(COLUMN)86(COLUMN)57 Columbus(COLUMN)66(COLUMN)47 Dal.-Ft. Worth(COLUMN)87(COLUMN)64 Dayton(COLUMN)73(COLUMN)41 Denver(COLUMN)71(COLUMN)42 Des Moines(COLUMN)68(COLUMN)42 Detroit(COLUMN)47(COLUMN)38 Dutluth(COLUMN)58(COLUMN)31 El Paso(COLUMN)58(COLUMN)31 Fairbanks(COLUMN)43(COLUMN)32 Fargo(COLUMN)60(COLUMN)29 Great Falls(COLUMN)60(COLUMN)29 Great Falls(COLUMN)37(COLUMN)32 Hartford(COLUMN)60(COLUMN)43 Helena(COLUMN)52(COLUMN)34 Honolulu(COLUMN)82(COLUMN)71 Houston(COLUMN)75(COLUMN)68 Indianapolis(COLUMN)73(COLUMN)45 Jackson(COLUMN)81(COLUMN)60 Jacksonville(COLUMN)85(COLUMN)61 Juneau(COLUMN)45(COLUMN)39 Kansas City(COLUMN)71(COLUMN)50 Las Vegas(COLUMN)76(COLUMN)54 Little Rock(COLUMN)87(COLUMN)62 Los Angeles(COLUMN)64(COLUMN)48 Louisville(COLUMN)76(COLUMN)47 Memphis(COLUMN)84(COLUMN)63 Miami Beach(COLUMN)77(COLUMN)74 Midland(COLUMN)88(COLUMN)58 Midland(COLUMN)88(COLUMN)58 Milwaukee(COLUMN)51(COLUMN)41 Mpls.-St. Paul(COLUMN)64(COLUMN)36 Nashville(COLUMN)83(COLUMN)55 New Orleans(COLUMN)78(COLUMN)65 New York(COLUMN)56(COLUMN)43 Norfolk(COLUMN)59(COLUMN)50 North Platte(COLUMN)72(COLUMN)48 Oklahoma City(COLUMN)85(COLUMN)62 Omaha(COLUMN)69(COLUMN)51 Orlando(COLUMN)87(COLUMN)64 Philadelphia(COLUMN)51(COLUMN)40 Phoenix(COLUMN)85(COLUMN)56 Pittsburgh(COLUMN)55(COLUMN)49 Portland, Maine(COLUMN)47(COLUMN)24 Portland, Ore.(COLUMN)55(COLUMN)35 Providence(COLUMN)58(COLUMN)38 Raleigh(COLUMN)80(COLUMN)53 Rapid City(COLUMN)68(COLUMN)34 Reno(COLUMN)48(COLUMN)29 Richmond(COLUMN)69(COLUMN)47 St. Louis(COLUMN)72(COLUMN)42 St. Prbg.-Tampa(COLUMN)86(COLUMN)65 Salt Lake City(COLUMN)66(COLUMN)52 San Antonio(COLUMN)77(COLUMN)63 San Francisco(COLUMN)55(COLUMN)48 San Juan(COLUMN)85(COLUMN)75 St. Ste. Marie(COLUMN)36(COLUMN)33 Seattle(COLUMN)53(COLUMN)39 Shreveport(COLUMN)83(COLUMN)57 Sioux Falls(COLUMN)67(COLUMN)38 Spokane(COLUMN)48(COLUMN)37 Syracuse(COLUMN)50(COLUMN)39 Topeka(COLUMN)72(COLUMN)45 Tucson(COLUMN)85(COLUMN)56 Tulsa(COLUMN)82(COLUMN)57 Washigton(COLUMN)58(COLUMN)47 Wichita(COLUMN)77(COLUMN)55(END TABLE) Temperatures (Western Hemisphere)(TABLE) City(COLUMN)Weather(COLUMN)H.(COLUMN)L. Acapulco(COLUMN)clear(COLUMN)87(COLUMN)73 Barbados(COLUMN)clear(COLUMN)86(COLUMN)73 Bermuda(COLUMN)pt. cldy.(COLUMN)78(COLUMN)63 Bogota(COLUMN)cloudy(COLUMN)68(COLUMN)54 Calgary(COLUMN)clear(COLUMN)39(COLUMN)21 Cullacan(COLUMN)clear(COLUMN)95(COLUMN)61 Edmonton(COLUMN)clear(COLUMN)37 28 Havana(COLUMN)pt. cldy.(COLUMN)83(COLUMN)64 Kingston(COLUMN)pt. cldy.(COLUMN)87(COLUMN)72 Montego Bay(COLUMN)pt. cldy.(COLUMN)84(COLUMN)72 Mexico City(COLUMN)cloudy(COLUMN)74(COLUMN)52 Monterrey(COLUMN)cloudy(COLUMN)85(COLUMN)66 Montreal(COLUMN)cloudy(COLUMN)37(COLUMN)28 Nassau(COLUMN)pt. cldy.(COLUMN)80(COLUMN)64 Ottawa(COLUMN)snow(COLUMN)41(COLUMN)130 Regina(COLUMN)clear(COLUMN)41(COLUMN)18 St. Kitts(COLUMN)pt. cldy.(COLUMN)85(COLUMN)69 St. Thomas(COLUMN)pt. cldy.(COLUMN)84(COLUMN)75 Toronto(COLUMN)pt. cldy.(COLUMN)39(COLUMN)34 Vancouver(COLUMN)clear(COLUMN)52(COLUMN)37 Veracruz(COLUMN)pt. cldy.(COLUMN)87(COLUMN)68 Winnipeg(COLUMN)clear(COLUMN)46(COLUMN)16(END TABLE)