Evening Update: Today's high/low of 68°/48° yield a daily departure from average of 9°, and the monthly departure increases to +5.6°. Added chart of daily departures for March.
With a week left to go in the first month of meteorological spring, Washington, DC temperatures are averaging 5.5° above the long-term March average. As noted earlier, winter temperatures averaged below normal mainly thanks to a cold February. However, the March warmth has more than compensated; combined with a slightly warm January, the year 2010 is averaging 0.4° above normal to date.
Even with some cooler temperatures in the forecast, especially over the weekend, the yearly temperature is likely to remain above average through the end of March. The remainder of the month would have to be at least 4.3° below average for the final January-March mean to be below normal.
Images (click to enlarge): March 2010 daily temperature departures from average, January-March 2010 monthly average temperature departures; CapitalClimate charts from National Weather Service data
5 weeks ago