The tornado outbreak sequence of May 2019
Volleys of tornadoes touched down for 14 straight days beginning May 17, 2019. As of June 3, 295 twisters have been confirmed* per the hard-working crew over at Wikipedia.
Amidst a stuck and active pattern, four major waves of upper-level low pressure passed through the Central U.S. over the two week period, each one helping spawn these daily events from the High Plains to the Northeast.
The sequence ended May 30 as the final wave of the grouping moved offshore after producing severe weather in the Mid-Atlantic.
While the tally of tornadoes from this extended outbreak is set to surpass an average for the month around 270 twisters, it truly stands out for the second half of the month (May 16-31).
Filtering out the weakest of tornadoes, the preliminary 163 confirmed EF1+ twisters in this stretch has set a new top mark for the back half of May since 1950. 2019 has seemingly surpassed the 155 EF1+ in 2004 and the 147 EF1 or greater in 2011.
The biggest day of the series came May 27 when 59 tornadoes occurred, including an EF4 in and around Dayton, Ohio. The next day another EF4 happened near Lawrence, Kansas. These twisters became the second and third violent (EF4+) tornadoes of the year. The first touched down in March and hit Beauregard, Alabama, following a record-breaking lack of them in 2018. At least four tornadoes caused fatalities, with a toll now at seven.
Given a preliminary total of at least 362 tornadoes in the month overall, May 2019 is sitting just outside the top 5 Mays on record for tornadoes. The number one spot there is 542 twisters in 2003. Two through four when it comes to the most tornadic Mays are 2004 (509), 2008 (460), 1995 (394), and 2015 (381).
|Day||Tornadoes||EF1+||Strong+||Max EF||Max SPC|
|May 17, 2019||17||9||6||3||03-Enh|
|May 18, 2019||19||16||8||3||03-Enh|
|May 19, 2019||20||15||0||1||02-Slt|
|May 20, 2019||11||9||4||3||05-High|
|May 21, 2019||25||16||3||3||03-Enh|
|May 22, 2019||19||15||5||3||04-Mod|
|May 23, 2019||15||11||2||3||04-Mod|
|May 24, 2019||16||7||0||1||03-Enh|
|May 25, 2019||10||6||2||3||03-Enh|
|May 26, 2019||27||14||1||2||04-Mod|
|May 27, 2019||59||22||10||4||03-Enh|
|May 28, 2019||16||12||6||4||04-Mod|
|May 29, 2019||39||11||3||2||03-Enh|
|May 30, 2019||2||1||0||1||02-Slt|
500 mb of the sequence
Maximum Storm Prediction Center tornado probability
*note: map above does not include two confirmed tornadoes, 1 in CA, 1 in ID. There were also 3 warnings; 2 in CA, 1 in ID. Given the busy nature of the map as is, we wanted to focus on the main outbreak region even if the western tornadoes were associated with the same upper-level troughs of low pressure.
Numbers here are preliminary and subject to change. Updates to this post will generally be once a day as new items develop. Last updated June 3 at 7:30 p.m. EDT.