Washington: Today - Sunny and warm, high 75 to 80, lows 40 to 50. Chance of rain is near zero through tonight. Winds will be southwesterly at 15 mph. Monday - Sunny and warm, high around 40.

Maryland and Virginia: Today - sunny, high in 70s and lows in 40s. Monday - sunny and warm, high in 70s.

Potomac and Chesapeake Bay: Today - Fair, visibility more than five miles. Winds will be southerly at 15 knots. Waves in unprotected waters will be 2 feet.

Extended Area Outlook for Tuesday through Thursday: There will be a chance of rain at the beginning of the period. The highs will average in the 60s and lows in the 40s except 30s in mountains. Normal Washington temperatures will be a high of 66 and a low of 46.

The Nation Yesterday: Showers were scattered through Arizona and New Mexico. The heaviest showers continued in the mountains of southern and central Arizona. Many normally dry washes through southern Arizona were overflowing. Scattered rains also spread across southwestern Colorado during the night. Light snow has already occuring through the areas above 9 thousand feet in western Colorado and southern Wyoming. With additional cooling tonight snow could become quite heavy in these higher elevations. The cloudy skies stretched from the Rockies across the northern Plains into the Great Lakes region. With very little sunshine temperatures still climbed into the 70s. The southeastern corner of the nation was still sunny with the Gulf Coast already in the 50s. The west coast was mostly sunny and mild. The Canadian air was pushing through the Pacific Northwest. Cloudy skies and temperatures in the 40s were the result.

The National Weather Forecast for today - Showers will spread across the Southwest into the central Rockies. The central Plains, and as far east as Missouri. Snow will continue in the higher elevations of Colorado and Wyoming. Cloudy skies will stretch into the Great Lakes region. The remainder of the nation will be sunny and dry. The cold spots will be across the northern and central Plains into the upper Great Lakes region. The cloudy skies and rain in the Southwest will keep the deserts in the 80s. Even southern Texas and southern Florida will only be in the middle 80s. The remainder of the nation will be mild.

Almanac Data for today: The sun rise 7:24 a.m., sets 6:20 p.m.; moon rise 11:29 p.m., sets 1:06 p.m. Tides: high 1:57 p.m. and 7:52 a.m., low 8:02 p.m. High and low tides at the following location 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 1/2), Norfolk (1), Virginia Beach (3/4), Solomons island (6 1/4), Point Lookout (7).

The Council of Government's Air Quality Index for yesterday showed the high reading in the Washington area during the 10 p.m. period was 23 for the pollutant, carbon monoxide. Index values between 0 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 National Weather Service forecasts the Potomac River stage at Little Falls should remain near 2.9 feet today. Local Temps, Humidity(TABLE) Time(COLUMN)T.(COLUMN)H. 2 midnight(COLUMN)43(COLUMN)71 1 a.m.(COLUMN)49(COLUMN)77 2 a.m.(COLUMN)48(COLUMN)80 3 a.m.(COLUMN)47(COLUMN)83 4 a.m.(COLUMN)47(COLUMN)83 5 a.m.(COLUMN)47(COLUMN)83 6 a.m.(COLUMN)45(COLUMN)80 7 a.m.(COLUMN)45(COLUMN)80 8 a.m.(COLUMN)46(COLUMN)80 9 a.m.(COLUMN)50(COLUMN)74 10 a.m.(COLUMN)52(COLUMN)80 1 a.m.(COLUMN)58(COLUMN)69 2 noon(COLUMN)64(COLUMN)58 1 p.m.(COLUMN)67(COLUMN)50 3 a.m.(COLUMN)71(COLUMN)46 4 p.m.(COLUMN)72(COLUMN)40 5 p.m.(COLUMN)73(COLUMN)37 6 p.m.(COLUMN)69(COLUMN)44(END TABLE) Temperature ending 8 a.m. (EDT) yesterday(TABLE) City(COLUMN)H.(COLUMN)L. Albany(COLUMN)55(COLUMN)32 Albuquerque(COLUMN)78(COLUMN)58 Amarillo(COLUMN)84(COLUMN)53 Anchorage(COLUMN)43(COLUMN)33 Asheville(COLUMN)73(COLUMN)33 Atlanta(COLUMN)76(COLUMN)44 Atalantic City(COLUMN)56(COLUMN)42 Austin(COLUMN)88(COLUMN)55 Baltimore(COLUMN)67(COLUMN)39 Billings(COLUMN)70(COLUMN)43 Birmingham(COLUMN)77(COLUMN)41 Bismarck(COLUMN)80(COLUMN)44 Boise(COLUMN)73(COLUMN)47 Boston(COLUMN)53(COLUMN)41 Brownsville(COLUMN)83(COLUMN)60 Buffalo(COLUMN)55(COLUMN)45 Burlington(COLUMN)51(COLUMN)45 Casper(COLUMN)71(COLUMN)44 Charleston, S.C.(COLUMN)74(COLUMN)56 Charleston, WVa.(COLUMN)66(COLUMN)37 Charlotte(COLUMN)75(COLUMN)43 Cheyenne(COLUMN)69(COLUMN)53 Chicago(COLUMN)72(COLUMN)51 Cincinnati(COLUMN)71(COLUMN)42 Cleveland(COLUMN)67(COLUMN)47 Columbia S.C.(COLUMN)20(COLUMN)40 Columbus(COLUMN)65(COLUMN)41 Dal.-Ft. Worth(COLUMN)90(COLUMN)52 Dayton(COLUMN)89(COLUMN)46 Denver(COLUMN)76(COLUMN)44 Des Moines(COLUMN)81(COLUMN)53 Detroit(COLUMN)67(COLUMN)42 Duluth(COLUMN)75(COLUMN)50 El Paso(COLUMN)83(COLUMN)63 Fargo(COLUMN)79(COLUMN)44 Flagstaff(COLUMN)50(COLUMN)34 Great Falls(COLUMN)70(COLUMN)39 Hartford(COLUMN)57(COLUMN)32 Helena(COLUMN)68(COLUMN)40 Honolulu(COLUMN)86(COLUMN)73 Houston(COLUMN)87(COLUMN)64 Indianapolis(COLUMN)73(COLUMN)45 Jackson, Miss.(COLUMN)83(COLUMN)47 Jacksonville(COLUMN)80(COLUMN)48 Juneau(COLUMN)43(COLUMN)42 Kansas City(COLUMN)83(COLUMN)57 Las Vegas(COLUMN)70(COLUMN)60 Little Rock(COLUMN)80(COLUMN)57 Los Angeles(COLUMN)75(COLUMN)63 Louisville(COLUMN)72(COLUMN)42 Memphis(COLUMN)80(COLUMN)50 Miami Beach(COLUMN)79(COLUMN)77 Milwaukee(COLUMN)67(COLUMN)49 Mpls.-St. Paul(COLUMN)78(COLUMN)51 Nashville(COLUMN)72(COLUMN)40 Midland-Odessa(COLUMN)79(COLUMN)53 New Orleans(COLUMN)83(COLUMN)54 New York(COLUMN)54(COLUMN)45 Norfolk(COLUMN)67(COLUMN)41 North Platte(COLUMN)86(COLUMN)47 Oklahoma City(COLUMN)92(COLUMN)59 Omaha(COLUMN)81(COLUMN)61 Orlando(COLUMN)85(COLUMN)59 Philadelphia(COLUMN)59(COLUMN)39 Phoenix(COLUMN)31(COLUMN)66 Pittsburgh(COLUMN)58(COLUMN)37 Portland, Me.(COLUMN)53(COLUMN)31 Portland, Ore.(COLUMN)59(COLUMN)36 Providence(COLUMN)58(COLUMN)35 Raleigh(COLUMN)71(COLUMN)38 Rapid City(COLUMN)81(COLUMN)51 Reno(COLUMN)74(COLUMN)39 Richmond(COLUMN)69(COLUMN)38 St. Louis(COLUMN)77(COLUMN)54 St. Prbg.-Tampa(COLUMN)84(COLUMN)61 Salt Lake City(COLUMN)66(COLUMN)50 San Antonio(COLUMN)85(COLUMN)50 San Francisco(COLUMN)62(COLUMN)55 San Juan(COLUMN)95(COLUMN)76 St. Ste. Marie(COLUMN)64(COLUMN)42 Seattle(COLUMN)57(COLUMN)47 Shreveport(COLUMN)29(COLUMN)56 Sioux Falls(COLUMN)78(COLUMN)45 Spokane(COLUMN)62(COLUMN)33 Syracuse(COLUMN)55(COLUMN)36 Topeka(COLUMN)83(COLUMN)47 Tucson(COLUMN)73(COLUMN)62 Tulsa(COLUMN)89(COLUMN)54 Washington(COLUMN)47(COLUMN)45 Wichita(COLUMN)84(COLUMN)50(END TABLE)