March arrives tomorrow.
March marks the start of both meteorological and astronomical spring.
It is definitely a time of transition in Alabama. As the days lengthen and the sun moves higher in the sky, average temperatures start to climb. The average high in Birmingham at the start of the month is 62F. By month’s end, the average daytime high is 70F. The average low at the start of the month is 39F.
By March 31st, the average is 45F. The warmest it has ever been in March was 90F on March 21st, 1907, as Birmingham was in the middle of an unusual heat wave.
The coldest March reading in Birmingham history was 2F on March 14, 1993. That was the day after the 1993 blizzard, which is also remarkable for producing the city’s biggest snowfall ever, 13 inches at the Birmingham Airport. The temperature generally drops to freezing or below on 6.1 days in the month. The average date of the last freeze usually occurs in mid to late March.
March is the wettest month of the year in Birmingham. On average, 6.10 inches of rain falls. The 15.80 inches that fell in March 1980 is the most ever recorded in the third month of the year. It occurred during a month of flooding. It rains on 11.0 days on average, which ranks third behind July at 12.4 days and January at 11.2 days.
Thunderstorms occur on 4.5 days. The months of April through August are all stormier, but March does mark the beginning of the primary severe weather season, at least in North and Central Alabama. Alabama’s deadliest tornado outbreak in history occurred on March 21, 1932. Shelby County was hard hit that day with a devastating tornado at Columbiana.
The percentage of possible sunshine is on the increase, averaging 55% in the month, up from the 42 percent that is typical of January, but still less than the 66 percent we usually see in May and October. The sky is cloudy 41 percent of the time. It is clear 24.2 percent of the time.
March is tied with April as the windiest month of the year, with an average wind speed of 10.4 mph.
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