Severe Weather Statistics

[venture]

This thread will be for the discussion mostly around Severe Weather Statistics and trends. This is not the thread to post things like "I'm good with no tornadoes" or "Need more" or other similar comments.

2014 was a well below average year when it came to severe weather, 2015 has started to trend that was as well. Severe weather seasons follow a pretty distinct path across the country. January the focus is on Texas and Southern Miss Valley. February it is again Texas and also further into Southeast. March we still see the Southeast well into their season while the Central and Southern Plains start to join in. Come April the Southeast is at their peak for the year and we see the Ohio Valley, Western Great Lakes/Midwest into Central and Southern Plains start to increase rapidly. May of course is peak season for the Southern Plains and expands well north tot he Canadian Border. July we see things shut down in the Southern Plains and focus more in the Northern/Central Plains and Colorado. August is much the same as July just fewer numbers. September we start to see things calm down and move more into the Carolina, Southeast, and Southern Plains. October is mostly Southern PLains and Southeast. November we are moving back to the Southern Miss Valley and Texas and that continues through December as well.

So far for 2015 we have not seen the Southeast US have their severe weather season yet. There have been three days so far this quarter where we've had watches up - January 3rd and 4th as well as February 25th. So far for the nation in January we had 24 tornadoes and in February only 2.

Tornado Trends

Hail and Wind Report Trends

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[bchris02]

How did 2013 start in the Texas and the Southeastern United States? That was one of the worst years in Oklahoma history but nationwide if my memory serves me well it was relatively quiet. What about other "big" Oklahoma years like 1999, 2003, and 2011?

[venture]

How did 2013 start in the Texas and the Southeastern United States?

Jan 2013 - 75 tornados over the Ohio Valley, Southern Miss Valley, and even one in NC OK. Tornado History Project: January, 2013
Feb 2013 - 39 tornadoes from TX along the Southeast Gulf coast states...and a couple odd balls in California. Tornado History Project: February, 2013
Mar 2013 - 18...mostly SE US, a couple in E OK.

So by most accounts a fair standard year when it comes to which areas were impacted.

That was one of the worst years in Oklahoma history but nationwide if my memory serves me well it was relatively quiet.

Well depends on how you want to frame "Worst years"...since it still was only the 10th most active tornado season since 1950. 2013 for Oklahoma had 4 tornadoes through the first quarter of the year.

What about other "big" Oklahoma years like 1999, 2003, and 2011?

1999 we started with 7...99 was also the most active year since 1950.
2003 isn't top 10...but we started with 4 in the first quarter.
2011 was a top 10 year...we started with only 1 in the first quarter.

I would recommend this to see what years were actually "big" years... Monthly/Annual statistics for Tornadoes in Oklahoma (1950-Present)

[LocoAko]

Well depends on how you want to frame "Worst years"...since it still was only the 10th most active tornado season since 1950. 2013 for Oklahoma had 4 tornadoes through the first quarter of the year.

Yeah, I don't necessarily agree with calling it one of the worst years in history, though I guess that is a subjective threshold. There were an above average number of tornadoes but it is far from being one of the worst ever -- there were just a few high-profile events and strong tornadoes. Keep in mind that the number of tornadoes reported yearly nationwide has increased dramatically since 1950 (and especially since 1990), primarily due to the increased reporting of EF0 tornadoes in the modern radar era.



Source: Storm Prediction Center Enhanced Fujita Scale (EF Scale)

[bchris02]

Is there anywhere I can find statistics on frequency and likelihood of EF3+ tornadoes by state going back to 1950? I did find something but it only accounts 1991-2010, which I don't think is a long enough stretch. According to this map, chances of getting hit by an F3+ tornado is actually higher in Dixie Alley than it is in Oklahoma.

[LocoAko]

For anyone interested, I know (most of) the people who run this site and they do some really great work with statistics/GIS.

Here's an article about the climatology of April tornadoes: Here?s where tornadoes typically form in April across the United States | United States Tornadoes

[bchris02]

The record for the most tornadoes for the month of May in Oklahoma is 91 in 2010, beating out the 1999 record of 90.

Will be interesting to see after tonight how close 2015 comes to that. There are still four more days of this as well.

[bchris02]

The total for May has been updated to 67 tornadoes. If no other tornadoes get added to the total for that month, that will make it the third biggest May on record for tornadoes, being beat out only by 2010 and 1999. Also interesting is that three of the top 5 years have occurred this decade.

[Urbanized]

^^^^^^^
Not as ominous as it sounds. In fairness technology has improved so greatly in the past couple of decades that the current era can't be accurately compared to the past. Many if not most tornados in prior decades were simply not documented.

[jn1780]

^^^^^^^
Not as ominous as it sounds. In fairness technology has improved so greatly in the past couple of decades that the current era can't be accurately compared to the past. Many if not most tornados in prior decades were simply not documented.

Very true, many of the small tornados this year would have gone unnoticed in prior years or have their damage classified as straight line wind damage.

[bchris02]

The total number of tornadoes for May 2015 has been bumped up to 75. 0 tornadoes happened in June this year.