Washington: Today -- Snow, high in the mid 30s, low near 30. The chance of precipitation is near 100 per cent today and 80 per cent tonight. Wednesday -- Rain, high near 40.

Maryland and Virginia: Today --Snow, highs from the 20s to the 30s, lows in the 20s. Wednesday --Rain, highs from the 30s to the 40s.

Lower Potomac and Chesapeake Bay: Today -- Snow with visibility of less than 3 miles. Wind will be from the northeast at up to 25 knots. Waves in unprotected waters will be from 2 to 3 feet.

Extended Area Forecast for Thursday through Saturday: Rain or snow possible on each day during the period. Highs will be from the 30s to the low 40s, lows from the 20s to the 30s. Normal Washington temperatures for the period are a high of 44 and a low of 28.

West Virginia: Today -- Snow, highs from the mid 20s to the low 30s lows in the mid 20s. Wednesday --Snow, highs from the mid 20s to the low 30s.

The National Weather Forecast for today -- Snow will spread from the Ohio Valley, the southern Great Lakes and Tennessee, eastward across the Appalachians into the northern and middle Atlantic states. Rain will fall along the southern Atlantic Coast and the central and eastern Gulf states. Showers will fall along the Pacific Coast and in southern Arizona, while snow will spread across much of the Plateau, the Rocky Mountains and the northwestern Plains. Skies will be partly cloudy or cloudy through the central part of the nation. Colder temperatures will dominate over the middle and lower Mississippi Valley and much of Texas. It will remain cold from the northern Plains to the northern Atlantic states. It will be warmer along the southern Atlantic Coast, while the West will be seasonably cool.

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 20 for the pollutant, photochemical oxidents. 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 forecasts the Potomac River stage at Little Falls should be near 4.1 feet today.

Almanac Data for today: Sun rises 7:25 a.m. sets 5:12 p.m.; moon rises 11:56 a.m., sets 12:37 p.m. Tides: high 2:26 a.m. and 2:59 p.m., low 9:13 a.m. and 9:50 p.m. High and low tides at the following locations may be obtained by subtracting the hours indicated from the tides above. Annapolis (1 1/2), Bloody Point Lighthouse (4 1/2), Deale, Md. (4 1/2), Colonial Beach (6), Morfolk (1 1/2), Virginia Beach (1), Solomons Island (6 1/2), Point Lookout (7).

Washington data at 7 p.m. (EST) yesterday: Highest temperature since 7 a.m. yesterday, 34 degrees at 2:05 p.m. Lowest temperature since midnight, 19 degrees at 6:05 a.m. Deficiency of temperature since Jan. 1, 29 degrees. Record high temperature for today, 72 degrees in 1943. Record low temperature for today, 2 degrees in 1977. Relative humidity: Maximum, 68 per cent at 6 a.m.; Minimum, 35 per cent at 2 p.m. Excess of precipitation since Jan. 1, 1.58 inches. Highest observed wind since 7 a.m. 9 miles per hour from the west at 10 a.m. Peak gust since 8 a.m., 16 miles per hour from the west at 10:13 a.m. (TABLE) Time(COLUMN)T.(COLUMN)H. 12 midnite(COLUMN)24(COLUMN)50 1 a.m.(COLUMN)23(COLUMN)55 2 a.m.(COLUMN)23(COLUMN)55 3 a.m.(COLUMN)22(COLUMN)57 4 a.m.(COLUMN)22(COLUMN)57 5 a.m.(COLUMN)21(COLUMN)65 6 a.m.(COLUMN)20(COLUMN)68 7 a.m.(COLUMN)20(COLUMN)62 8 a.m.(COLUMN)21(COLUMN)59 9 a.m.(COLUMN)23(COLUMN)55 10 a.m.(COLUMN)27(COLUMN)48 11 a.m.(COLUMN)30(COLUMN)43 12 noon(COLUMN)30(COLUMN)43 1 p.m.(COLUMN)32(COLUMN)41 2 p.m.(COLUMN)33(COLUMN)35 3 p.m.(COLUMN)33(COLUMN)40 4 p.m.(COLUMN)34(COLUMN)42 5 p.m.(COLUMN)33(COLUMN)49 6 p.m.(COLUMN)32(COLUMN)50 7 p.m.(COLUMN)32(COLUMN)51(END TABLE)

Temperatures ending 8 a.m. (EST) yesterday: (TABLE) City(COLUMN)H(COLUMN)L. Albany(COLUMN)22(COLUMN)15 Albuquerque(COLUMN)44(COLUMN)32 Amarillo(COLUMN)57(COLUMN)26 anchorage(COLUMN)21(COLUMN)5 Asheville(COLUMN)28(COLUMN)9 Atlanta(COLUMN)31(COLUMN)18 Atlantic City(COLUMN)26(COLUMN)20 Austin(COLUMN)60(COLUMN)50 Baltimore(COLUMN)29(COLUMN)15 Billings(COLUMN)8(COLUMN)-2 Birmingham(COLUMN)36(COLUMN)24 Bismarck(COLUMN)5(COLUMN)-26 Boise(COLUMN)47(COLUMN)40 Boston(COLUMN)30(COLUMN)16 Brownville(COLUMN)76(COLUMN)67 Buffalo(COLUMN)15(COLUMN)12 Burlington(COLUMN)15(COLUMN)10 Casper(COLUMN)25(COLUMN)-14 Charleston, S.C.(COLUMN)41(COLUMN)30 C'stown, w. Va.(COLUMN)21(COLUMN)1 Charlotte(COLUMN)40(COLUMN)20 Cheyenne(COLUMN)30(COLUMN)1 Chicago(COLUMN)18(COLUMN)8 Cincinnati(COLUMN)20(COLUMN)3 Cleveland(COLUMN)21(COLUMN)4 Columbia, S.C.(COLUMN)41(COLUMN)19 Columbus(COLUMN)20(COLUMN)4 Dal. Ft. Worth(COLUMN)47(COLUMN)47 Dayton(COLUMN)20(COLUMN)6 Denver(COLUMN)32(COLUMN)9 Des Moines(COLUMN)17(COLUMN)4 Detroit(COLUMN)22(COLUMN)9 Duluth(COLUMN)16(COLUMN)-7 El Paso(COLUMN)54(COLUMN)48 Fairbanks(COLUMN)-2(COLUMN)-13 Fargo(COLUMN)7(COLUMN)-18 Flagstaff(COLUMN)37(COLUMN)26 Great Falls(COLUMN)9(COLUMN)zero Hartford(COLUMN)26(COLUMN)8 Helena(COLUMN)25(COLUMN)7 Honolulu(COLUMN)78(COLUMN)74 Houston(COLUMN)60(COLUMN)53 Indianapolis(COLUMN)21(COLUMN)8 Jackson, Miss.(COLUMN)43(COLUMN)30 Jacksonville(COLUMN)45(COLUMN)25 Juneau(COLUMN)29(COLUMN)15 Kansas City(COLUMN)25(COLUMN)17 Las Vegas(COLUMN)61(COLUMN)40 Little Rock(COLUMN)29(COLUMN)26 Los Angeles(COLUMN)62(COLUMN)54 Louisville(COLUMN)23(COLUMN)11 Memphis(COLUMN)33(COLUMN)31 Miami Beach(COLUMN)59(COLUMN)43 Midland-Odessa(COLUMN)53(COLUMN)45 Milwaukee(COLUMN)17(COLUMN)4 Mpls.-St. Paul(COLUMN)14(COLUMN)-8 Nashville(COLUMN)28(COLUMN)20 New Orleans(COLUMN)44(COLUMN)38 New York(COLUMN)25(COLUMN)17 Norfolk(COLUMN)37(COLUMN)22 North Platte(COLUMN)6(COLUMN)2 Oklahoma City(COLUMN)38(COLUMN)33 Omaha(COLUMN)18(COLUMN)2 Orlando(COLUMN)48(COLUMN)30 Philadelphia(COLUMN)26(COLUMN)15 Phoenix(COLUMN)65(COLUMN)48 Pittsburgh(COLUMN)20(COLUMN)11 Portland, Maine(COLUMN)31(COLUMN)11 Portland, Ore.(COLUMN)51(COLUMN)42 Providence(COLUMN)30(COLUMN)12 Raleigh(COLUMN)39(COLUMN)17 Rapid City(COLUMN)13(COLUMN)-6 Reno(COLUMN)47(COLUMN)37 Richmond(COLUMN)34(COLUMN)16 St. Louis(COLUMN)25(COLUMN)20 St. Prbg.-Tampa(COLUMN)46(COLUMN)29 Salt Lake City(COLUMN)45(COLUMN)36 San Antonio(COLUMN)63(COLUMN)61 San Francisco(COLUMN)59(COLUMN)93 San Juan(COLUMN)86(COLUMN)74 St. Ste. Marie(COLUMN)14(COLUMN)-5 Seattle(COLUMN)55(COLUMN)50 Shreveport(COLUMN)45(COLUMN)40 Sioux Falls(COLUMN)12(COLUMN)-14 Spokane(COLUMN)40(COLUMN)31 Syracuse(COLUMN)16(COLUMN)14 Topeka(COLUMN)29(COLUMN)19 Tulsa(COLUMN)32(COLUMN)30 Washington(COLUMN)33(COLUMN)19 Wichita(COLUMN)36(COLUMN)23(END TABLE)

Temperatures Abroad Yesterday (TABLE) City(COLUMN)Weather(COLUMN)Time(COLUMN)Temp. Aberdeen(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)37 Amsterdam(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)39 Ankara(COLUMN)pt. cldy.(COLUMN)3 p.m.(COLUMN)32 Athens(COLUMN)pt. cldy.(COLUMN)2 p.m.(COLUMN)57 Auckland(COLUMN)clear(COLUMN)m-nigt(COLUMN)64 Berlin(COLUMN)clear(COLUMN)1 p.m.(COLUMN)37 Birmingham(COLUMN)smoke(COLUMN)1 p.m.(COLUMN)36 Brussels(COLUMN)pt. cldy(COLUMN)1 p.m.(COLUMN)41 Casablanca(COLUMN)rain(COLUMN)noon(COLUMN)54 Copenhagen(COLUMN)clear(COLUMN)1 p.m.(COLUMN)36 Dublin(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)37 Geneva(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)36 Hong Kong(COLUMN)cloudy(COLUMN)8 p.m.(COLUMN)54 Lisbon(COLUMN)cloudy(COLUMN)noon(COLUMN)54 London(COLUMN)rain(COLUMN)1 p.m.(COLUMN)41 Madrid(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)36 Malta(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)57 Manila(COLUMN)clear(COLUMN)8 p.m.(COLUMN)79 Moscow(COLUMN)pt. cldy.(COLUMN)3 p.m.(COLUMN)16 New Delhi(COLUMN)pt. cldy.(COLUMN)5 p.m.(COLUMN)70 Nice(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)45 Oslo(COLUMN)snow(COLUMN)1 p.m.(COLUMN)32 Paris(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)37 Peking(COLUMN)cloudy(COLUMN)8 p.m.(COLUMN)23 Rome(COLUMN)pt. cldy.(COLUMN)1 p.m.(COLUMN)57 Saigon(COLUMN)pt. cldy.(COLUMN)8 p.m.(COLUMN)82 Sofia(COLUMN)cloudy(COLUMN)2 p.m.(COLUMN)32 Stockholm(COLUMN)clear(COLUMN)1 p.m.(COLUMN)34 Sydney(COLUMN)pt. cldy.(COLUMN)10 p.m.(COLUMN)86 Tel Aviv(COLUMN)pt. cldy.(COLUMN)2 p.m.(COLUMN)63 Tokyo(COLUMN)clear(COLUMN)9 p.m.(COLUMN)39 Tunis(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)46 Vienna(COLUMN)cloudy(COLUMN)1 p.m.(COLUMN)32 Warsaw(COLUMN)clear(COLUMN)1 p.m.(COLUMN)34(END TABLE)

Temperatures (Western Hemisphere) (TABLE) City(COLUMN)Weather(COLUMN)High(COLUMN)Low Acapulco(COLUMN)fair(COLUMN)86(COLUMN)73 Bermuda(COLUMN)fair(COLUMN)73(COLUMN)63 Bogora(COLUMN)pt. cldy.(COLUMN)66(COLUMN)46 Calgary(COLUMN)snow(COLUMN)7(COLUMN)zero Edmonton(COLUMN)clear(COLUMN)7(COLUMN)-6 Havana(COLUMN)clear(COLUMN)68(COLUMN)52 Kingston(COLUMN)fair(COLUMN)79(COLUMN)69 Monteco Bay(COLUMN)pt. cldy.(COLUMN)75(COLUMN)68 Mexico City(COLUMN)haze(COLUMN)73(COLUMN)48 Monterrey(COLUMN)fair(COLUMN)73(COLUMN)53 Montreal(COLUMN)clear(COLUMN)12(COLUMN)-2 Nassau(COLUMN)fair(COLUMN)66(COLUMN)50 Ottawa(COLUMN)clear(COLUMN)7(COLUMN)-8 Regina(COLUMN)snow(COLUMN)zero(COLUMN)-27 St. Kitts(COLUMN)cloudy(COLUMN)82(COLUMN)71 St. Thomas(COLUMN)pt. cldy.(COLUMN)85(COLUMN)70 Toronto(COLUMN)pt. cldy.(COLUMN)12(COLUMN)10 Vancouver(COLUMN)clear(COLUMN)46(COLUMN)34 Veracruz(COLUMN)clear(COLUMN)77(COLUMN)57 Winnipeg(COLUMN)snow(COLUMN)1(COLUMN)-27(END TABLE)