Notable April Severe Weather Outbreaks

April 5 Severe Weather Reports (Source: NOAA)

The most active time of the year for severe weather in the United States starts in April and runs through June.  There has been a significant amount of severe weather during the last few days across much of the United States.  In fact, NOAA’s Storm Prediction Center placed a portion of the Mid-Atlantic Region under moderate risk for severe weather today.  “Severe weather” is defined as a thunderstorm that contains any of the following: 1) hail at least 1” in diameter or greater; 2) wind gusts of at least 58 mph; or 3) a tornado.

Let’s take a look at recent April severe weather outbreaks in the United States.

2016: Nearly five hundred severe weather reports occurred in a massive outbreak on April 26 that spanned from Texas to the Mid-Atlantic Region.  Although there were 35 confirmed tornadoes, the most frequent type of severe weather during this event were severe wind gusts. 

2015:  On April 19, a total of 335 cases of severe weather were reported.  This outbreak spanned from Texas to Florida, and north to the Tennessee Valley.  On April 9, nearly 300 cases of severe weather occurred in an even larger geographic area, which ranged from parts of Texas to Michigan to North Carolina.  A total of 49 tornadoes were confirmed by meteorologists on these two days, but, fortunately, no fatalities were reported. 

2014: One of the largest April tornado outbreaks of recent memory occurred on April 28 in the southeastern United States.  That’s when 121 tornadoes developed which were part of nearly 360 cases of severe weather overall.  The majority of the tornadoes occurred in Mississippi and Alabama, with a tragic 31 reported fatalities.  NOAA data indicates April averages 155 tornadoes, so to see 121 in just a single day underscores how significant this outbreak was.  The high death toll serves as a reminder of how important having a plan of action is to seek safety should dangerous weather approach.  

2012: On April 14, a total of 344 reported cases of severe weather developed from Texas to Illinois.  Roughly a third of these severe reports included 122 tornadoes.  The majority of the tornadoes on this day developed in the state of Kansas, right in the middle of “Tornado Alley.”  As it turned out, April 2012, saw the highest number of tornadoes (233) of any month that year, according to NOAA data.

March Gives Way to April

Lake Needwood, Derwood, Maryland

Last month continued the recent trend of being warmer and drier than average in the Nation’s Capital.  March’s average temperature was 47.2 degrees in Washington, D.C. (0.4 degrees warmer than average).  For the first time on record March was warmer than average and still finished cooler than February (47.7 degrees) in Washington, D.C.  The last time February was warmer than March in the Nation’s Capital was in 1984.

March 1 had a record-tying high temperature of 80 degrees, but that was followed by the coldest stretch of weather since early January.  In a rare occurrence, March also became the snowiest month of this winter, with a monthly total of 2.0”.  Also, March 31 was Washington, D.C.’s wettest day (with 0.96” of rain) since December 6.  A total of 3.19” of rain fell at National Airport last month (0.29” below normal).

Average high and low temperatures in the Nation’s Capital range from 62/42 degrees on April 1 to 71/52 degrees on April 30.  According to NOAA, April’s hottest temperature in Washington, D.C. is 95 degrees and that occurred most recently on April 17, 2002.  Washington, D.C.’s coldest April temperature is 15 degrees (April 1, 1923).  It’s interesting to note that 15 of the last 20 Aprils have been warmer than average in the Nation’s Capital.

Gardeners, farmers and baseball fans alike want to know how much rain can be expected this April.  Well, Washington, D.C. averages 3.06” and NOAA’s monthly outlook is for near average rainfall.  On rare occasions, Washingtonians have even seen small amounts of April snow; most recently, on April 7, 2007 when 0.4” accumulated.  The latest in the measureable spring snowfall in Washington, D.C. occurred on April 28, 1898 when 0.5” of snow was observed.

The frequency of severe weather in the United States also increases dramatically in April.  Based on NOAA statistics, the month of April has the third highest average number of tornadoes in the United States behind only May and June.  For example, the strongest tornado on record in the state of Maryland occurred on April 28, 2002.  That’s when an F4 tornado decimated the town of La Plata, Maryland in Charles County.  Fortunately, the forecast is for dry and comfortable weather on Opening Day at Nationals Park tomorrow.

Weather Quiz

True or False.  May 2016 was the last wetter than average month in the Nation’s Capital.

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Answer to March 10 Weather Quiz question.

True.