Washington: Today - Rain, high near 50, low in the mid 20s. The chance of precipitation is 93 per cent today and 80 per cent tonight. Monday - Partly cloudy, high in upper 30s.

Maryland and Virginia: Today - Rain, highs in the 50s, lows from the teens to the 20s. Monday - Rain ending, highs from the 20s to the 30s. There will be snow squalls in the mountains.

Lower Potomac and Chesapeake Bay: Today - Rain with visibility of less than 3 miles today, becoming more than 5 miles tonight. Wind will be from the south at up to 25 knots today, shifting to from the northwest tonight. Waves in unprotected waters will be from 2 and 3 feet.

Extended Area Forecast for Tuesday through Thursday: Fair through the period. There will be a chance of snow flurries in the mountains. Highs will be from the mid 20s to the mid 30s, lows from near 5 in the mountains, to the low 20s elsewhere. Normal Washington temperatures for the period are a high of 43 and a low of 28.

West Virginia: Today - Rain, highs from the mid 40s to the low 50s, lows from the teens to the low 20s. Monday - Partly cloudy, chance of occasional snow flurries, highs from the upper teens to the 20s.

The National Weather Forecast for today - Snow will cover most of the Great Lakes and Northern Maine while rain will reach from Ohio across New York and most of New England through the Ohio Valley to the eastern Gulf and Atlantic Coasts. Scattered thunder-showers will extend from Louisiana and Mississippi through Tennessee into Kentucky. Showers will extend from the northern half of California through the Pacific Northwest and will scatter across Utah, Idaho and northern Nevada. Snow flurries will fall over the northern and central Rockies and the high central plains. Fair to partly cloudy skies will persist elsewhere. It will be very cold from Montana across the northern plains and turn colder in the central plains and the mid Mississippi Valley. Near seasonable temperatures will continue from the eastern Great Lakes through the lower Mississippi Valley across the southern plains, as well as the southern and central Rockies and intermountain regions.

The Council of Governments Air Quality Index for yesterday showed the high reading in the Washington area during the 9 a.m. to 10 a.m. period was 7 for the pollutant, photochemical oxidants. Index values between zero 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 be good.

The National Weather Service foremasts the Potomac River stage at Little Falls should be near 3.6 feet today. Local Temp., Humidity(TABLE) Time(COLUMN)T(COLUMN)H 12 midnight(COLUMN)42(COLUMN)82 1 a.m.(COLUMN)42(COLUMN)82 2 a.m.(COLUMN)42(COLUMN)79 3 a.m.(COLUMN)42(COLUMN)79 4 a.m.(COLUMN)41(COLUMN)86 5 a.m.(COLUMN)41(COLUMN)86 6 a.m.(COLUMN)41(COLUMN)86 7 a.m.(COLUMN)40(COLUMN)89 8 a.m.(COLUMN)41(COLUMN)86 9 a.m.(COLUMN)41(COLUMN)87 10 a.m.(COLUMN)41(COLUMN)89 11 a.m.(COLUMN)42(COLUMN)89 12 noon(COLUMN)43(COLUMN)86 1 p.m.(COLUMN)43(COLUMN)86 2 p.m.(COLUMN)43(COLUMN)86 3 p.m.(COLUMN)43(COLUMN)86 4 p.m.(COLUMN)42(COLUMN)86 5 p.m.(COLUMN)42(COLUMN)86 6 p.m.(COLUMN)41(COLUMN)89(END TABLE)(TABLE) City(COLUMN)H(COLUMN)L Albany(COLUMN)30(COLUMN)32 Albuquerque(COLUMN)52(COLUMN)32 Amarillo(COLUMN)65(COLUMN)39 Anchorage(COLUMN)18(COLUMN) 5 Asheville(COLUMN)54(COLUMN)34 Atlanta(COLUMN)54(COLUMN)50 Atlantic City(COLUMN)50(COLUMN)42 Austin(COLUMN)76(COLUMN)61 Baltimore(COLUMN)45(COLUMN)40 Billings(COLUMN)40(COLUMN) 7 Birmingham(COLUMN)62(COLUMN)54 Bismarck(COLUMN) 9(COLUMN) 1 Boise(COLUMN)49(COLUMN)34 Boston(COLUMN)45(COLUMN)35 Brownsville(COLUMN)85(COLUMN)70 Buffalo(COLUMN)29(COLUMN)23 Burlington(COLUMN)18(COLUMN) 0 Casper(COLUMN)40(COLUMN)19 Charleston, S.C.(COLUMN)65(COLUMN)47 Charleston, W.Va.(COLUMN)46(COLUMN)44 Charlotte(COLUMN)53(COLUMN)48 Cheyenne(COLUMN)44(COLUMN)29 Chicago(COLUMN)37(COLUMN)30 Cincinnati(COLUMN)39(COLUMN)30 Cleveland(COLUMN)39(COLUMN)34 Columbia, S.C.(COLUMN)55(COLUMN)45 Columbus(COLUMN)35(COLUMN)34 Dal.-Ft. Worth(COLUMN)77(COLUMN) 4 Dayton(COLUMN)36(COLUMN)34 Denver(COLUMN)55(COLUMN)27 Des Moines(COLUMN)36(COLUMN)34 Detriot(COLUMN)32(COLUMN)30 Duluth(COLUMN)24(COLUMN)21 El Paso(COLUMN)64(COLUMN)48 Fairbanks(COLUMN)64(COLUMN)48 Fairbanks(COLUMN)16(COLUMN)25 Fargo(COLUMN)16(COLUMN) 8 Flagstaff(COLUMN)41(COLUMN)19 Great Falls(COLUMN)42(COLUMN)12 Hartford(COLUMN)39(COLUMN)32 Helena(COLUMN)46(COLUMN)20 Honolulu(COLUMN)82(COLUMN)71 Houston(COLUMN)78(COLUMN)68 Indianapolis(COLUMN)40(COLUMN)38 Jackson, Miss.(COLUMN)73(COLUMN)57 Jacksonville(COLUMN)75(COLUMN)47 Juneau(COLUMN)15(COLUMN)10 Kansas City(COLUMN)40(COLUMN)34 Las Vegas(COLUMN)60(COLUMN)40 Little Rock(COLUMN)58(COLUMN)47 Los Angeles(COLUMN)63(COLUMN)58 Louisville(COLUMN)45(COLUMN)37 Memphis(COLUMN)62(COLUMN)44 Miami Beach(COLUMN)74(COLUMN)71 Midland-Odessa(COLUMN)72(COLUMN)41 Milwaukee(COLUMN)35(COLUMN)33 Mpls.-St. Paul(COLUMN)31(COLUMN)26 Nashville(COLUMN)59(COLUMN)41 New Orleans(COLUMN)79(COLUMN)63 New York(COLUMN)44(COLUMN)35 Norfolk(COLUMN)54(COLUMN)43 North Platte(COLUMN)43(COLUMN)24 Oklahoma City(COLUMN)66(COLUMN)37 Omaha(COLUMN)38(COLUMN)24 Orlando(COLUMN)79(COLUMN)53 Philadelphia(COLUMN)47(COLUMN)37 Phoenix(COLUMN)69(COLUMN)53 Pittsburgh(COLUMN)40(COLUMN)38 Portland, Maine(COLUMN)34(COLUMN)15 Portland, Ore.(COLUMN)43(COLUMN)37 Providence(COLUMN)40(COLUMN)31 Raleigh(COLUMN)50(COLUMN)40 Rapid City(COLUMN)43(COLUMN)17 Reno(COLUMN)49(COLUMN)25 Richmond(COLUMN)50(COLUMN)39 St. Louis(COLUMN)50(COLUMN)42 St. Prbg.-Tampa(COLUMN)76(COLUMN)61 Salt Lake City(COLUMN)48(COLUMN)32 San Antonio(COLUMN)73(COLUMN)54 San Diego(COLUMN)66(COLUMN)53 San Francisco(COLUMN)60(COLUMN)52 San Juan(COLUMN)84(COLUMN)73 St. Ste. Marie(COLUMN)15(COLUMN)12 Seattle(COLUMN)42(COLUMN)39 Shreveport(COLUMN)79(COLUMN)57 Sioux Falls(COLUMN)25(COLUMN)22 Spokane(COLUMN)38(COLUMN)13 Syracuse(COLUMN)32(COLUMN)24 Topeka(COLUMN)47(COLUMN)35 Tucson(COLUMN)66(COLUMN)44 Tulsa(COLUMN)50$36 Washington(COLUMN)48(COLUMN)40 Wichita(COLUMN)53(COLUMN)30(END TABLE)