Weather Facts



Why is March such a windy month?

You may wonder why March is such a windy month compared to the other months of the year. While there are several reasons, I will highlight the major reasons. The extreme contrast in temperatures causes major storms to develop on occasion. Cold air masses can be every bit as cold as they were during the middle of the winter. The barometric pressure in the core of these air masses increases to very high levels. At the same time, the increasing sunshine over the temperate zones produces warm air masses to begin developing and moving north. The low pressure areas combined with departing high pressure areas produce the southerly winds that bring this warm air in contact with the still very cold air that dives down from the north. The pressure differences between the strong high pressure areas and the deep low pressure areas make for some windy days in March. Another reason it is windy in March is the increased atmospheric instability caused by the increasingly strong sunshine. This heats the earth's surface and since warm air is lighter than cold air, the air rises. This process results in more "mixing" of the air, which tends to bring down the stronger winds from the upper atmosphere. The very different air masses that move into the U.S. cause the huge fluctuations in temperatures making one day feel like summer and the next day feel like winter. Once we get into the month of April, the cold air masses moderate and while there could still be some large contrasts in temperatures and large intense storms, the warm air begins to start winning the battle. Note that November tends to be a windy month also, as we see the extra-tropical storms begin to strengthen and the difference in air mass temperatures increase.

Dave