Washington: Today - Hot and humid, high 100, low in the upper 70s. The chance of rain is 20 per cent through tonight. Thursday - Hot and humid, high near 100.

Maryland and Virginia: Today - Hot and humid, highs from the low 90s to near 100, lows in the 70s. Thursday - Hot and humid, highs from the low 90s to near 100.

Lower Potomac and Chesapeake Bay: Today - Fair with a chance of thunderstorms. Winds will be from the west at less than 12 knots. Winds will be strong and gusty in more than 5 miles, except for between 2 and 5 miles in haze and rain. Waves in unprotected waters will be less than 1 foot.

Atlantic Ocean Beaches from Cape May to Cape Hatteras: Today and Thursday - Sunny, highs in the 90s. Water temperatures will range from the low 70s in the north to the near 80 in the south.

Extended Area Forecast for Thursday through Saturday: Hot and humid through the period, but a chance of thundershowers on Friday. Highs will be in the 90s, lows in the 70s. Normal Washington temperatures for the period are a high of 89 and a low of 70.

West Virginia: Today - Hot and humid, highs from the mid 60s to the mid 70s. Thursday - Hot and humid, highs from the mid 80s to the mid 90s.

The National Weather Forecast for Showers and thunderstorms will extend from the central Appalachians across the central Atlantic Coast, then southward through the Tennessee Valley and the Gulf Coast. Showers will scatter widely over much of New England and from western portions of the upper plains across the southern two-thirds of the Rockies into eastern portions of the lower intermountain region. Temperatures will be mild over the northern and desert southwest, but warm to hot over most of the remainder of the nation. Temperatures will be very hot from eastern portions of the northern Plains. Across the Great Lakes, as well as in the northeast from New England through New Jersey.

Almanac Data for today - Sun rises 5:59 a.m., sets 8:30 p.m; moon rises 10:19 a.m. sets 10:29 p.m., low 5:57 a.m.and 6:15 p.m. High and low tides at the following locations can be obtained by subtracting the hours indicated from the tides above, Annapolis from the tides above, Lighthouse (3 1/2); Bloody Point Lighthouse (4 1'2); Deale, Md. (4 1/2); Colonial Beach (1) Solomons Island (6 1/2); Point Lookout (7), Pollen count; 4 English Plaintain (note for is considered undesirable.)

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 135 for the pollutant, photochemical oxidants. When the index exceeds 100 the air becomes hazardous and persons with lung, heart and eye problems should restrict their activity. The air pollution alert is in effect.

Th e National Weather Service forecasts that the Potomaac River stage at Little Falls will be near 2.9 feet. Local Temp. Humidity(TABLE) Time(COLUMN)T.(COLUMN)H. 1 a.m.(COLUMN)79(COLUMN)87 2 a.m.(COLUMN)77(COLUMN)91 3 a.m.(COLUMN)76(COLUMN)94 4 a.m.(COLUMN)76(COLUMN)94 5 a.m.(COLUMN)76(COLUMN)94 6 a.m.(COLUMN)97 7 a.m.(COLUMN)76(COLUMN)88 8 a.m.(COLUMN)80(COLUMN)79 9 a.m.(COLUMN)84(COLUMN)70 10 a.m.(COLUMN)86(COLUMN)66 11 a.m.(COLUMN)89(COLUMN)60 12 noon(COLUMN)91(COLUMN)56 1 p.m.(COLUMN)92(COLUMN)53 2 p.m.(COLUMN)94(COLUMN)51 3 p.m.(COLUMN)94(COLUMN)51 4 p.m.(COLUMN)94(COLUMN)42 5 p.m.(COLUMN)94(COLUMN)53 6 p.m.(COLUMN)92(COLUMN)58 7 p.m.(COLUMN)92(COLUMN)58(END TABLE) Temperatures ending 8 a.M. (EDT) Yesterday(TABLE) City(COLUMN)H. . Albany(COLUMN)94(COLUMN)66 Alburquerque(COLUMN)94(COLUMN)68 Amarlio(COLUMN)95(COLUMN)72 Anchorage(COLUMN)75(COLUMN)60 Asheville(COLUMN)90(COLUMN)62 Atlanta(COLUMN)90(COLUMN)69 Atlantic City(COLUMN)92(COLUMN)71 Austin(COLUMN)95(COLUMN)74 Baltimore(COLUMN)90(COLUMN)70 Billings(COLUMN)98(COLUMN)58 Birmingham(COLUMN)92(COLUMN)76 Bismarck(COLUMN)98(COLUMN)69 Boise(COLUMN)94(COLUMN)60 Boston(COLUMN)91(COLUMN)69 Brownsville(COLUMN)94(COLUMN)77 Buffalo(COLUMN)91(COLUMN)76 Burlington(COLUMN)85(COLUMN)66 Casper(COLUMN)98(COLUMN)73 Charleston, S.C.(COLUMN)92(COLUMN)80 Charlton, W. Va.(COLUMN)96(COLUMN)72 Charlotte(COLUMN)97(COLUMN)74 Cheyenne(COLUMN)89(COLUMN)65 Chicago(COLUMN)88(COLUMN)78 Cincinnati(COLUMN)93(COLUMN)73 Cleveland(COLUMN)91(COLUMN)71 Columbia, S.C.(COLUMN)97(COLUMN)70 Columbus(COLUMN)92(COLUMN)74 Dal-Ft. Worth(COLUMN)99(COLUMN)73 Dayton(COLUMN)96(COLUMN)75 Denver(COLUMN)97(COLUMN)68 Des Moines Detroit(COLUMN)95(COLUMN)68 Diluta(COLUMN)84(COLUMN)67 El Pasa(COLUMN)99(COLUMN)70 Fairbanks(COLUMN)70(COLUMN)50 Fargo(COLUMN)97(COLUMN)80 Flagstaff(COLUMN)80(COLUMN)50 Great Falls(COLUMN)83(COLUMN)57 Hartford(COLUMN)94(COLUMN)69 Helena(COLUMN)80(COLUMN)57 Honolulu(COLUMN)87(COLUMN)76 Houston(COLUMN)92(COLUMN)78 Indianapolis(COLUMN)93(COLUMN)72 Jackson, Miss.(COLUMN)91(COLUMN)90 Jacksonville(COLUMN)92(COLUMN)70 Juneau(COLUMN)60(COLUMN)51 Kansas City(COLUMN)94(COLUMN)77 Las Vegas(COLUMN)107(COLUMN)85 Los Angeles(COLUMN)86(COLUMN)64 Louisville(COLUMN)95(COLUMN)77 Memphis(COLUMN)97(COLUMN)79 Midland-Odessa(COLUMN)96(COLUMN)69 Milwaukee(COLUMN)86(COLUMN)74 Mpl-St Palu(COLUMN)95(COLUMN)79 Nashville(COLUMN)95(COLUMN)76 New Orleans(COLUMN)91(COLUMN)75 New York(COLUMN)95(COLUMN)875 Norfolk(COLUMN)97(COLUMN)79 North Flatte(COLUMN)99(COLUMN)70 Oklahoma City(COLUMN)97(COLUMN)70 Omaha(COLUMN)98(COLUMN)77 Orlando(COLUMN)88(COLUMN)71 Philadelphia(COLUMN)95(COLUMN)74 Phoenix(COLUMN)100(COLUMN)82 Pittsburg(COLUMN)87(COLUMN)69 Portland, Me.(COLUMN)89(COLUMN)59 Portland, Ore.(COLUMN)73(COLUMN)53 Providence(COLUMN)95(COLUMN)71 Raleigh(COLUMN)97(COLUMN)73 Rapid City(COLUMN)105(COLUMN)74 Reno(COLUMN)94(COLUMN)78 Richmond(COLUMN)101(COLUMN)74 St. Louis(COLUMN)96(COLUMN)78 St. praba-Tampa(COLUMN)91(COLUMN)73 Salt Lake City(COLUMN)97(COLUMN)71 San Antonio(COLUMN)92(COLUMN)77 San Diego(COLUMN)78(COLUMN)67 San Juan(COLUMN)87(COLUMN)76 St. Ste. Marie(COLUMN)82(COLUMN)61 Seattle(COLUMN)73(COLUMN)57 Shreveport(COLUMN)98(COLUMN)65 Sioux Falls(COLUMN)93(COLUMN)78 Spokane(COLUMN)72(COLUMN)54 Syracuse(COLUMN)89(COLUMN)70 Topeka(COLUMN)93(COLUMN)70 Tucson(COLUMN)96(COLUMN)75 Tuisa(COLUMN)100(COLUMN)77 Washington(COLUMN)92(COLUMN)74 Wichita(COLUMN)101(COLUMN)74(END TABLE) Temperatures Abroad Yesterday(TABLE) City(COLUMN)WEather(COLUMN)Time(COLUMN)Temp. Aberdeen(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)57 Amsterdam(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)64 Ankara(COLUMN)clear(COLUMN)3 p.m.(COLUMN)77 Athens(COLUMN)clear(COLUMN)2 p.m.(COLUMN)86 Auckland(COLUMN)rain(COLUMN)midnight(COLUMN)52 Berlin(COLUMN)rain(COLUMN)1 p.m.(COLUMN)63 Birmingham(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)64 Brussels(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)63 Cairo(COLUMN)clear(COLUMN)2 p.m.(COLUMN)93 Casablanca(COLUMN)clear(COLUMN) noon(COLUMN)75 Copenhagen(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)59 Dublin(COLUMN)rain(COLUMN)1 p.m.(COLUMN)63 Geneva(COLUMN)clear(COLUMN)1 p.m.(COLUMN)75 Hong kong(COLUMN)rain(COLUMN)8 p.m.(COLUMN)79 Lisbon(COLUMN)clear(COLUMN) noon(COLUMN)77 London(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)66 Madrid(COLUMN)clear(COLUMN)1 p.m.(COLUMN)90 Malta(COLUMN)clear(COLUMN)1 p.m.(COLUMN)91 Manila(COLUMN)cloudy(COLUMN)8 p.m.(COLUMN)81 Moscow(COLUMN)pt. cldy(COLUMN)3 p.m.(COLUMN)72 New Delhi(COLUMN)rain(COLUMN)5 p.m.(COLUMN)82 Nice(COLUMN)clear(COLUMN)1 p.m.(COLUMN)77 Oslo(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)61 Paris(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)64 Peking(COLUMN)cloudy(COLUMN)8 p.m.(COLUMN)82 Rome(COLUMN)clear(COLUMN)1 p.m.(COLUMN)81 Saigon(COLUMN)cloudy(COLUMN)8 p.m.(COLUMN)81 Sofla(COLUMN)clear(COLUMN)2 p.m.(COLUMN)77 Stockholm(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)54 Sydney(COLUMN)clear(COLUMN)10 p.m.(COLUMN)50 Tel Aviv(COLUMN)clear(COLUMN)2 P.m.(COLUMN)88 Tokyo(COLUMN)clear(COLUMN)9 p.m.(COLUMN)77 Tunis(COLUMN)clear(COLUMN)1 p.m.(COLUMN)90 Vienna(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)72 Warsaw(COLUMN)rain(COLUMN)1 p.m.(COLUMN)61(END TABLE) Temperatures (Western Hemisphere)(TABLE) City(COLUMN)Weather(COLUMN)High(COLUMN)Low Acapulco sunny(COLUMN)92(COLUMN)73 Barbados(COLUMN)cloudy(COLUMN)96(COLUMN)75 Bermuda(COLUMN)pt. cldy(COLUMN)86(COLUMN)80 Calgary(COLUMN)pt. cldy(COLUMN)64(COLUMN)39 Culacne(COLUMN)pt. cldy(COLUMN)101(COLUMN)76 Edmonton(COLUMN)cloudy(COLUMN)61(COLUMN)39 Havana(COLUMN)cloudy(COLUMN)94(COLUMN)74 Kingston(COLUMN)sunny(COLUMN)90(COLUMN)79 Montego Bay(COLUMN)sunny(COLUMN)90(COLUMN)74 Mexico City(COLUMN)haze(COLUMN)77(COLUMN)57 Monterrey(COLUMN)pt. cldy(COLUMN)95(COLUMN)74 Montreal(COLUMN)pt. cldy(COLUMN)81(COLUMN)70 Nassau(COLUMN)cloudy(COLUMN)86(COLUMN)74 Ottawa(COLUMN)clear(COLUMN)82(COLUMN)72 Regina(COLUMN)rain(COLUMN)82(COLUMN)55 St. Kitts(COLUMN)pt. cldy(COLUMN)89(COLUMN)79 St.Thomas(COLUMN)fair(COLUMN)85(COLUMN)80 Vancouver(COLUMN)clear(COLUMN)86(COLUMN)52 Veracruz(COLUMN)pt. cldy(COLUMN)77(COLUMN)76 Winnipeg(COLUMN)clear(COLUMN)90 64(END TABLE)