Washington: Today - Variable cloudiness, high 84 to 88, low 70 to 75. Chance of showers is 40 percent today and 50 percent tonight. Winds will be light and variable. Saturday - Party cloudy with showers likely, high in upper 80s.

Maryland and Virginia: Today - Variable cloudiness with showers and thunderstorms, high in 80s, low in mid 60s. Saturday - Cloudy with thunderstorms likely, high in 80s.

Lower Potomac and Chesapeake Bay: Today - Fair visibility more than five miles except in rain. There is a chance of thunderstorms through tonight. Winds will be southeasterly at 10 knots. Waves in unprotected waters will be one foot.

Atlantic Ocean Beaches from New Jersey to North Carolina: Partly coudy with a chance of thunderstorms today and Saturday. Highs will be near 80. Water temperatures will be in the low 70s in the north and low 80s in the south.

Extended Area Outlook for Sunday through Tuesday: Partly coudy, warm and humid with a chance of afternoon or evening thunderstorms. Highs will average in the mid 80s to the low 90s, lows mid 60s to low 70s. Normal Washington temperatures for the period will be a high of 87 and a low of 68.

The Nation Yesterday: Showers and occasional thundershowers were scattered over the Atlantic Coast, from Florida to southern New England through the Ohio Valley and Gulf States. Showers and thundershowers were also scattered from the upper Mississippi Valley across east Kansas and Oklahoma into the Texas panhandle. Other showers were widely scattered through the northern and central Rockies. Tropical storm Cora continued on a westward path. The center was located about 680 miles southeast of no threat to the Leeward Islands, the Virgin Islands of Puerto Rico if Cora continues on this course.

The National Westher Forecast for today - Showers and scattered thundershowers will reach from the northern Atlantic Coast through Florida, across the southern two thirds of the Appalachians, the Ohio Valley, the Tennessee Valley, the eastern Gulf states and the western half of the Gulf Coast into central Texas. Showers will also be scattered from the northwest Pacific Coast into western Montana. Temperatures will be hot across the northern Plains into the upper Mississippi Valley and the upper Missouri Valley. Mild temperatures will reach from the Tennessee Valley through the southern half of the Appalachians into southeastern New York state. Temperatures elsewhere over the nation will be seasonably warm.

Almanac Data for today: The sun rises 6:18 a.m., sets 8:06 p.m.; moon rises 12:38 p.m. sets 12:28 a.m. Tides: high 1:29 a.m. and 1:50 p.m. low 8:28 a.m. and 8:19 p.m. High and low tides at the following locations may be obtained by subtracting the hours indicated from the hours above: Annapolis (3 1/2), Bloody Point Lighthouse (4 1/2), Deale, Md. (4 1/2), Colonial Beach (5 1/4), Norfolk (1), Virginia Beach (), 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 to 3 p.m. period was 50 for the pollutant, photo-chemical oxidents. 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 fall to 4.0 feet today.

Washington data for yesterday: Highest temperature since midnight yesterday, 89 degrees at 3:40 p.m. Lowest temperature since midnight, 73 degrees at 1:0 a.m. Excess of temperature since Aug. 1, 30 degrees. Deficiency of temperature since Jan. 1, 111 degrees. Record high temperature for today, 101 degree in 1900. Record low temperature for today, 56 degrees in 1879. Relative humidity: maximum, 94 percent at 3 a.m.; minimum, 57 percent at 5 p.m. 24 hour precipitation, .32 inches. Deficiency of precipitation since Aug. 1, .05 inches. Excess of precipitation since Jan. 1, 2.87 inches. Highest observed wind since 8 a.m., 12 miles per hour from the west at 4:53 p.m. Peak gust since 8 a.m. 18 miles per hour from the northwest at 1:02 p.m. Local Temps., Humidity(TABLE) Time(COLUMN)T.(COLUMN)H. 12 midnite(COLUMN)74(COLUMN)88 1 a.m.(COLUMN)73(COLUMN)91 2 a.m.(COLUMN)73(COLUMN)91 3 a.m.(COLUMN)73(COLUMN)91 4 a.m.(COLUMN)73(COLUMN)94 5 a.m.(COLUMN)73(COLUMN)94 6 a.m.(COLUMN)73(COLUMN)94 7 a.m.(COLUMN)73(COLUMN)94 8 a.m.(COLUMN)73(COLUMN)94 9 a.m.(COLUMN)75(COLUMN)88 10 a.m.(COLUMN)79(COLUMN)77 11 a.m.(COLUMN)82(COLUMN)69 12 noon(COLUMN)85(COLUMN)59 1 p.m.(COLUMN)85(COLUMN)61 2 p.m.(COLUMN)86(COLUMN)59 3 p.m.(COLUMN)87(COLUMN)57 4 p.m.(COLUMN)88(COLUMN)57 5 p.m.(COLUMN)87(COLUMN)59 6 p.m.(COLUMN)64(COLUMN)67 7 p.m.(COLUMN)84(COLUMN)67(END TABLE) Temperatures ending 8 p.m. (EDT) yesterday(TABLE) City(COLUMN)H.(COLUMN)L. Albany(COLUMN) 86(COLUMN)66 Albuquerque(COLUMN) 89(COLUMN)59 Amarillo(COLUMN) 80(COLUMN)65 Anchorage(COLUMN) 70(COLUMN)59 Asheville(COLUMN) 78(COLUMN)65 Atlanta(COLUMN) 78(COLUMN)66 Atlantic City(COLUMN) 83(COLUMN)69 Austin(COLUMN) 95(COLUMN)75 Billings(COLUMN) 91(COLUMN)60 Birmingham(COLUMN) 82(COLUMN)71 Bismarck(COLUMN) 87(COLUMN)58 Boise(COLUMN) 99(COLUMN)66 Boston(COLUMN) 86(COLUMN)70 Brownsville(COLUMN) 93(COLUMN)74 Buffalo(COLUMN) 79(COLUMN)58 Casper(COLUMN) 88(COLUMN)57 Charleston, S.C.(COLUMN) 88(COLUMN)78 Charleston, W.Va.(COLUMN) 82(COLUMN)64 Charlotte(COLUMN) 88(COLUMN)69 Cheyenne(COLUMN) 75(COLUMN)55 Chicago(COLUMN) 82(COLUMN)65 Cincinnati(COLUMN) 84(COLUMN)68 Cleveland(COLUMN) 84(COLUMN)68 Columbia, S.C.(COLUMN) 90(COLUMN)72 Columbus(COLUMN) 86(COLUMN)67 Dal.-Ft. Worth(COLUMN) 96(COLUMN)68 Dayton(COLUMN) 86(COLUMN)64 Denver(COLUMN) 86(COLUMN)53 Des Moines(COLUMN) 88(COLUMN)65 Detroit(COLUMN) 85(COLUMN)59 Duluth(COLUMN) 74(COLUMN)48 El Paso(COLUMN) 84(COLUMN)65 Fairbanks(COLUMN) 80(COLUMN)60 Fargo(COLUMN) 80(COLUMN)61 Flagstaff(COLUMN) 83(COLUMN)48 Great Falls(COLUMN) 96(COLUMN)60 Hartford(COLUMN) 85(COLUMN)66 Helena(COLUMN) 95(COLUMN)57 Honolulu(COLUMN) 87(COLUMN)74 Houston(COLUMN) 94(COLUMN)77 Indianapolis(COLUMN) 88(COLUMN)49 Jackson, Miss.(COLUMN) 76(COLUMN)72 Jacksonville(COLUMN) 90(COLUMN)73 Juneau(COLUMN) 58(COLUMN)54 Kansas City(COLUMN) 90(COLUMN)70 Las Vegas(COLUMN)111(COLUMN)84 Little Rock(COLUMN) 91(COLUMN)69 Los Angeles(COLUMN) 88(COLUMN)70 Louisville(COLUMN) 88(COLUMN)71 Memphis(COLUMN) 89(COLUMN)74 Miami Beach(COLUMN) 85(COLUMN)80 Midland-Odessa(COLUMN) 89(COLUMN)67 Milwaukee(COLUMN) 76(COLUMN)61 Mpls.-St. Paul(COLUMN) 80(COLUMN)57 Nashville(COLUMN) 85(COLUMN)68 New Orleans(COLUMN) 86(COLUMN)77 New York(COLUMN) 87(COLUMN)73 Norfolk(COLUMN) 92(COLUMN)70 North Platte(COLUMN) 87(COLUMN)58 Oklahoma City(COLUMN) 95(COLUMN)75 Omaha(COLUMN) 87(COLUMN)74 Orlando(COLUMN) 90(COLUMN)74 Philadelphia(COLUMN) 89(COLUMN)72 Phoenix(COLUMN)107(COLUMN)88 Pittsburgh(COLUMN) 83(COLUMN)63 Portland, Ma.(COLUMN) 88(COLUMN)64 Portland, Ore.(COLUMN) 94(COLUMN)59 Providence(COLUMN) 84(COLUMN)70 Raleigh(COLUMN) 91(COLUMN)70 Rapid City(COLUMN) 88(COLUMN)57 Reno(COLUMN)100(COLUMN)51 Richmond(COLUMN) 92(COLUMN)70 St. Louis(COLUMN) 91(COLUMN)66 St. Prbg.-Tampa(COLUMN) 92(COLUMN)72 Salt Lake City(COLUMN) 99(COLUMN)64 San Antonio(COLUMN) 92(COLUMN)73 San Diego(COLUMN) 77(COLUMN)71 San Francisco(COLUMN) 62(COLUMN)53 San Juan(COLUMN) 88(COLUMN)78 St. Ste. Marie(COLUMN) 68(COLUMN)53 Seattle(COLUMN) 85(COLUMN)54 Shreveport(COLUMN) 93(COLUMN)68 Sioux Falls(COLUMN) 82(COLUMN)58 Spokane(COLUMN) 98(COLUMN)63 Syracuse(COLUMN) 87(COLUMN)62 Topeka(COLUMN) 91(COLUMN)66 Tucson(COLUMN) 98(COLUMN)78 Tulsa(COLUMN) 98(COLUMN)75 Washington(COLUMN) 91(COLUMN)73 Wichita(COLUMN) 95(COLUMN)68(END TABLE) Temperatures Abroad Yesterday(TABLE) City(COLUMN)Weather(COLUMN)Time(COLUMN)T. Aberdeen(COLUMN)cloudy(COLUMN) 1 p.m.(COLUMN)57 Amsterdam(COLUMN)pt. cldy(COLUMN) 1 p.m.(COLUMN)68 Ankara(COLUMN)clear(COLUMN) 3 p.m.(COLUMN)95 Athens(COLUMN)clear(COLUMN) 2 p.m.(COLUMN)86 Auckland(COLUMN)clear(COLUMN)12 a.m.(COLUMN)55 Berlin(COLUMN)clear(COLUMN) 1 p.m.(COLUMN)68 Birmingham (COLUMN)pt. cldy(COLUMN) 1 p.m.(COLUMN)61 Bonn(COLUMN)pt. cldy(COLUMN) 1 p.m.(COLUMN)66 Brussels(COLUMN)pt. cldy(COLUMN) 1 p.m.(COLUMN)64 Casablanca(COLUMN)clear(COLUMN)12 p.m.(COLUMN)70 Copenhagen(COLUMN)pt. cldy(COLUMN) 1 p.m.(COLUMN)72 Dublin(COLUMN)pt. cldy(COLUMN) 1 p.m.(COLUMN)63 Geneva(COLUMN)cloudy(COLUMN) 1 p.m.(COLUMN)59 Hong Kong(COLUMN)cloudy(COLUMN) 3 p.m.(COLUMN)82 Jerusalem(COLUMN)clear(COLUMN) 2 p.m.(COLUMN)84 Lisbon(COLUMN)clear(COLUMN)12 p.m.(COLUMN)82 London(COLUMN)cloudy(COLUMN) 1 p.m.(COLUMN)63 Madrid(COLUMN)clear(COLUMN) 1 p.m.(COLUMN)81 Malta(COLUMN)clear(COLUMN) 1 p.m.(COLUMN)86 Manila(COLUMN)cloudy(COLUMN) 8 p.m.(COLUMN)77 Moscow(COLUMN)cloudy(COLUMN) 3 p.m.(COLUMN)64 New Delhi(COLUMN)pt. cldy(COLUMN) 5 p.m.(COLUMN)88 Nice(COLUMN)clear(COLUMN) 1 p.m.(COLUMN)73 Olso(COLUMN)cloudy(COLUMN) 1 p.m.(COLUMN)63 Paris(COLUMN)cloudy(COLUMN) 1 p.m.(COLUMN)63 Peking(COLUMN)clear(COLUMN) 3 p.m.(COLUMN)75 Rome(COLUMN)clear(COLUMN) 1 p.m.(COLUMN)79 Saigon(COLUMN)cloudy(COLUMN)8 p.m.(COLUMN)79 Sofia(COLUMN)cloudy(COLUMN) 2 p.m.(COLUMN)68 Stockholm(COLUMN)pt. cldy(COLUMN) 1 p.m.(COLUMN)66 Sydney(COLUMN)clear(COLUMN)10 p.m.(COLUMN)52 Tokyo(COLUMN)clear(COLUMN) 9 p.m.(COLUMN)84 Tunis(COLUMN)clear(COLUMN) 1 p.m.(COLUMN)84 Vienna(COLUMN)rain(COLUMN) 1 p.m.(COLUMN)63 Warsaw(COLUMN)pt. cldy(COLUMN) 1 p.m.(COLUMN)68(END TABLE)