Friday, March 22, 2024

Many Tornadoes In Ohio Thus Far. How Does This Compare to Past Years?


Uncharacteristically, late February and March thus far, has been a very active period for severe weather across Ohio. While we do see more frequent day-to-day weather fluctuation across the southern Great Lakes and Ohio this month (and April) than in any other month, severe weather doesn't always accompany these changes.

The first severe weather event occurred on February 28th. 

Only 2 hail reports with this first round in late February. No tornadoes.  Most of the storm reports (hail, wind and tornadoes) were across central Ohio.

The second round was far more extensive March. A total of 18 tornado warnings across Ohio and 6 in northeastern Ohio. The NWS in Cleveland also has a great recap here.

5 tornadoes were confirmed in northeastern Ohio. A total of 15 across Ohio.

Storm Reports in March 2024

Radar - March 14, 2024
So far this year's Ohio severe weather reports:

Plymouth, Ohio damage from March 14, 2024 tornado

Is the number of tornado unprecedented for Ohio through late March?  I looked back at the total OHIO tornado count through March since 1950 and separated the totals (red)  with the EF2+ totals (green).  Here is what I found:

Ohio Tornado Count: 1950 - 1985 (thru March)

Ohio Tornado Count: 1986 - 2024 (thru march)

There were brief upticks in tornadoes in the mid 50s and a few instances in the 70s but nothing        really high.  The peaks were 1985, 1986, 2012, 2016 and 2017. Here is the early season 1986 tornado tracks:

Here are some additional bullet points on the graphics above:

*  Two of the three tornadoes in 1992 were EF2+.  One was an EF4.
*  The 1991 tornado was an EF3
*  Six of the nine early season tornadoes in 1986 were EF2+

However, over the last 2 years, early season Ohio tornado counts have rose significantly.  17 in 2023.  26 in 2024 through March. Five of those were EF2 tornadoes. One was in Crawford/Huron counties.

For spatial perspective here is the January through March tornado locations for 2023 and 2024:

Jan, Feb, March Tornado Locations - 2023

Jan, Feb, March tornado locations - 2024

Tornado warnings in 2023 through mid March vs tornado warning in 2024 through mid March:


What were the causes of the uptick last year and this year?  Is this a fluke increase or something that we will see more in the years ahead?

One piece to the puzzle may be the Madden Julian Oscillation (MJO). This was in a high amplitude state in both years.  First image is last Jan through March 2023, second image is this year through late March. (More on this in the weeks ahead)

Strong Phase 7,8 and 1 in March of 2023

Strong phase 4,5 and 6 in March 2024

In my opinion, it's hard to draw a long term conclusion based on only a few severe weather events over a few weeks. So while we had two years with an uptick in early season tornadoes in Ohio, we need to monitor the next 3-5 years to see if a trend develops.