U.S. Severe Weather Blog

This blog is intended to facilitate communication about the impacts of selected severe weather events, particularly major tornadoes, in the United States in near-real-time. We hope it will allow us to assist media, forecasters, researchers, emergency managers, and other interested parties to understand what we at the NOAA Weather Partners in Norman, Oklahoma have been able to gather about the events. We also hope to include information that puts recent events into historical perspective and provide guidance about how to interpret the record of reported events.

This blog is not intended to provide critical weather forecast information. For that, go to the National Weather Service Offsite link warning, especially the Storm Prediction Center Offsite link warning for national guidance, and your local National Weather Service Forecast Office for local information. Find it here Offsite link warning. Nor is this intended to provide information on a broad range of research topics associated with severe weather. For that, go to the National Severe Storms Laboratory Offsite link warning.

Low Tornado Numbers and Low Tornado Deaths, May 2012-April 2013

May 1st, 2013 | By Harold Brooks

Updated 10 May 2013 to add new information from April 2013 Updated 2 May 2013 to correct typo on date of previous low tornado count The 12-month period from May 2012 to April 2013 was remarkable for the absence of tornado activity and tornado impacts in the United States. We can start by looking at […]


The Tornado “Drought” of 2012

Aug 2nd, 2012 | By Harold Brooks

UPDATE (14-Aug-2012): Graph corrected to indicate 2006 as previous 15 Apr-31 Jul minimum. The 2012 tornado season in the United States got off to a quick start with well-above average numbers in January, February, and March. Later, over 80 tornadoes occurred on 14 April. Since then, the number of tornadoes in the US has been […]


No Tornado Deaths in May 2012

Jun 7th, 2012 | By Harold Brooks

In May 2012, there were no tornado deaths in the United States. How unusual was that? We can look at the record of tornado deaths, discussed here, dating back to 1875. The last time there were no deaths in the month of May was in 2005. Prior to that, it was 1994. Overall, there have […]


Bi-monthly Tornado Counts and ENSO Phase Strength

Sep 28th, 2011 | By Greg Carbin

The charts below illustrate that occasional weak cool-season links may occur between the phase strength of the EL NiƱo Southern Oscillation (ENSO phase strength) and EF1 to EF5 tornado reports for bi-monthly periods from 1950 through 2010 (1951 to 2011 for the last pair, Dec-Jan period). The charts display a simple running sum of EF1 […]


April 4-5, 2011 Severe Weather

Apr 6th, 2011 | By Greg Carbin

A review of this past week’s widespread severe weather event…


10 May 2010 tornado outbreak

May 11th, 2010 | By Harold Brooks

Information on the 10 May 2010 tornado outbreak in Oklahoma and Kansas


Some brief notes on the 24 April 2010 long-track tornado

Apr 26th, 2010 | By Harold Brooks

Preliminary information on the long-track tornado that went from eastern Louisiana across much of Mississippi. 1. It had a path length of at least 97 miles. Over the last 40 years, we’ve averaged about one 100 mile path length tornado every 2 years. Update (27 April): The path length is now given as 149 miles, […]


Can tornado activity through April portend May?

Apr 16th, 2010 | By Greg Carbin

Short answer: apparently not! Longer answer follows. Few tornadoes have occurred to date in 2010, especially when compared to very active recent years such as 2008. The adjusted annual tornado trend shown below indicates that 2010, with 79 tornadoes (adjusted) through April 15, is rapidly approaching the minimum number of tornadoes expected through this time […]


One tornado in February 2010 (UPDATED)

Mar 1st, 2010 | By Harold Brooks

A late tornado report has been received, so there’s now 1 tornado in the database for February 2010.


U.S. tornado droughts since 1990

Dec 1st, 2009 | By Greg Carbin

How does the 23-day tornado drought in November 2009 compare with other years?