Tornado History Project http://www.tornadohistoryproject.com/blog - Over 54,500 tornado maps. US tornadoes from 1950-2010. Sat, 04 May 2013 00:52:12 +0000 en hourly 1 http://wordpress.org/?v=3.2.1 2012 data added http://www.tornadohistoryproject.com/blog/2013/05/03/2012-data-added/ http://www.tornadohistoryproject.com/blog/2013/05/03/2012-data-added/#comments Sat, 04 May 2013 00:52:12 +0000 admin http://www.tornadohistoryproject.com/blog/?p=80 Though this announcement is a little late, effective April 15, 2013 the Tornado History Project added tornado data for 2012*. There were 940 confirmed tornadoes last year, which is the lowest annual number since 2002 registered 932 tornadoes. The total number of tornadoes mapped on this site (covering the period 1950-2012) now stands at 57,154.

There were also a relatively large number of changes to tornadoes in prior years, but unlike similar updates in the past, a itemized list will not be given. Instead, if you have previously downloaded data, simply re-download to get the most up to date information.

* Raw data has been provided by the Storm Prediction Center (SPC).

]]> http://www.tornadohistoryproject.com/blog/2013/05/03/2012-data-added/feed/ 0 Another data update http://www.tornadohistoryproject.com/blog/2012/07/26/another-data-update/ http://www.tornadohistoryproject.com/blog/2012/07/26/another-data-update/#comments Fri, 27 Jul 2012 01:38:11 +0000 admin http://www.tornadohistoryproject.com/blog/?p=76 As usual, when the SPC edits or adds data to their historical tornado data, the changes are carried over to the Tornado History Project. Here is a summary of recent changes:

]]> http://www.tornadohistoryproject.com/blog/2012/07/26/another-data-update/feed/ 0 Data updates – part 2 http://www.tornadohistoryproject.com/blog/2012/05/07/data-updates-%e2%80%93-part-2/ http://www.tornadohistoryproject.com/blog/2012/05/07/data-updates-%e2%80%93-part-2/#comments Tue, 08 May 2012 03:35:09 +0000 admin http://www.tornadohistoryproject.com/blog/?p=71 As explained in Data updates – part 1, the SPC periodically updates their historical tornado file, and when they do, the Tornado History Project carries those changes over. This is part 2 of 2 of a detailed list of those changes:

]]> http://www.tornadohistoryproject.com/blog/2012/05/07/data-updates-%e2%80%93-part-2/feed/ 0 Data updates – part 1 http://www.tornadohistoryproject.com/blog/2012/04/26/data-updates-part-1/ http://www.tornadohistoryproject.com/blog/2012/04/26/data-updates-part-1/#comments Fri, 27 Apr 2012 02:47:29 +0000 admin http://www.tornadohistoryproject.com/blog/?p=64 As noted in an earlier post, the SPC recently made changes to the pre-2011 historical files. Here’s a list so far, covering the period from 1950-2004. All the changes noted are already live on this site. There will be a future article for the 2005-2010 changes.

]]> http://www.tornadohistoryproject.com/blog/2012/04/26/data-updates-part-1/feed/ 1 2011 data edited http://www.tornadohistoryproject.com/blog/2012/04/10/2011-data-edited/ http://www.tornadohistoryproject.com/blog/2012/04/10/2011-data-edited/#comments Wed, 11 Apr 2012 04:04:06 +0000 admin http://www.tornadohistoryproject.com/blog/?p=57 The SPC has made some changes to the 2011 data, which have been carried over here. While the tornado count changed for two states (1 more for Oklahoma, 1 less for Tennessee), the total tornado count for the year remained the same. A list of the changes:

  • 20110427.13.19 – SPC tornado number changed from 296789 to 305268 on the Tennessee state segment to match the main record
  • 20110425.47.21 – SPC tornado number changed from 317910 to 297448 for the main record and both state segments to eliminate a conflict with another record numbered 317910

    • 20110427.47.38 – tornado removed (Tennessee)

  • 20110523.26.2 – Fujita rating changed from 1 to 0, damage changed from 15,000 to 0, touchdown coordinates changed to 46.2625, -85.7272, length changed to 2.4, and width changed to 50
  • 20111107.40.362650 – tornado added (Oklahoma)
  • 20111107.40.110 – state tornado number changed from 110 to 111
  • 20111107.40.111 – state tornado number changed from 111 to 112
  • 20111107.40.112 – state tornado number changed from 112 to 113
  • 20111107.40.113 – state tornado number changed from 113 to 114
  • 20111107.40.114 – state tornado number changed from 114 to 115
  • 20111107.40.115 – state tornado number changed from 115 to 116
  • 20111107.40.116 – state tornado number changed from 116 to 117
  • 20111107.40.117 – state tornado number changed rom 117 to 118
  • 20111108.40.118 – state tornado number changed from 118 to 119
  • 20111222.13.38 – Fujita rating changed from 1 to 3, injuries changed from 0 to 4, lift-off coordinates changed to 34.48, -84.86, length changed to 11.42, and width changed to 880

One more quick note…The SPC also made a number of revisions to tornado records for past years. These changes are being compiled and will be posted as soon as they are sorted out.

]]> http://www.tornadohistoryproject.com/blog/2012/04/10/2011-data-edited/feed/ 1 2011 data added http://www.tornadohistoryproject.com/blog/2012/04/03/2011-data-added/ http://www.tornadohistoryproject.com/blog/2012/04/03/2011-data-added/#comments Wed, 04 Apr 2012 03:26:21 +0000 admin http://www.tornadohistoryproject.com/blog/?p=46 The Tornado History Project is happy to announce that year 2011 tornadoes have been added to the database*. There were 1692 tornadoes logged last year, which makes it the 2nd highest annual total on record. This brings the total number of tornadoes mapped on the site to 56,221, covering the period 1950-2011.

Unfortunately, it was also a very deadly year with 550 fatalities and 5479 injuries. To put that into perspective, the total number of fatalities for the previous ten years combined was 563. Some of the most notable tornadoes of the year were this F5 tornado that struck Joplin and surrounding areas in Missouri, and this F4 tornado that struck Tuscaloosa and surrounding areas in Alabama.

A quick reminder about the approximate paths drawn on the maps. Due to the relatively small set of points included in the SPC data (typically only a touch-down and lift-off point), the generated paths are not exact. There are plans to improve path accuracy, but this is not yet ready for release. You can read more about how approximate paths are generated and their limitations by clicking the red “Disclaimer” link on any map page such as this F5 tornado in Alabama.

* As always, the raw data has been provided by the Storm Prediction Center (SPC).

]]> http://www.tornadohistoryproject.com/blog/2012/04/03/2011-data-added/feed/ 0 Minor data change http://www.tornadohistoryproject.com/blog/2011/09/16/minor-data-change/ http://www.tornadohistoryproject.com/blog/2011/09/16/minor-data-change/#comments Sat, 17 Sep 2011 03:27:28 +0000 admin http://www.tornadohistoryproject.com/blog/?p=40 Just noticed that the SPC made a very minor edit to their historical data file. As always, this change has been carried over to the Tornado History Project.

The tornado in question is 19681117.28.13, where the lift-off coordinates were changed from 30.8,-88.92 to 31.67,-89.93. While the data has been updated, this had no effect on the map since the approximate path was reproduced with data from the NCDC (see Enhanced Paths Explained), which already had the correct coordinates.

]]> http://www.tornadohistoryproject.com/blog/2011/09/16/minor-data-change/feed/ 0 2010 tornado data added http://www.tornadohistoryproject.com/blog/2011/03/27/2010-tornado-data-added/ http://www.tornadohistoryproject.com/blog/2011/03/27/2010-tornado-data-added/#comments Mon, 28 Mar 2011 02:55:31 +0000 admin http://www.tornadohistoryproject.com/blog/2011/03/27/2010-tornado-data-added/ Just a quick note to announce that year 2010 tornadoes have been added to the database*. There were 1282 tornadoes added for last year, which caused a total of 45 fatalities and 701 injuries. The most noteworthy tornado of the year is this F4 on April 24 that tore through parts of Mississippi and Louisiana killing 10 and injuring 146 while causing an estimated $386 million in damages.

With this latest update, there are now 54,529 tornadoes to explore at the Tornado History Project.

* Thanks to the SPC for collecting and providing the data.

]]> http://www.tornadohistoryproject.com/blog/2011/03/27/2010-tornado-data-added/feed/ 2 Data updates http://www.tornadohistoryproject.com/blog/2010/10/06/data-updates/ http://www.tornadohistoryproject.com/blog/2010/10/06/data-updates/#comments Thu, 07 Oct 2010 04:07:43 +0000 admin http://www.tornadohistoryproject.com/blog/2010/10/06/data-updates/ As you may know, the Tornado History Project uses data from the Storm Prediction Center’s (SPC) historical archive to generate maps and tables. So when the SPC updates their archive with new stats and information, the Tornado History Project incorporates those changes into our database. A quick summary of the recent changes follows:

*Index numbers are generated by the Tornado History Project to uniquely identify tornadoes within the site. The index number is not part of the official SPC data.

]]> http://www.tornadohistoryproject.com/blog/2010/10/06/data-updates/feed/ 0 2008, 2006, 2000, and 1971 data updated http://www.tornadohistoryproject.com/blog/2010/03/24/2008-2006-2000-and-1971-data-updated/ http://www.tornadohistoryproject.com/blog/2010/03/24/2008-2006-2000-and-1971-data-updated/#comments Thu, 25 Mar 2010 03:10:05 +0000 admin http://www.tornadohistoryproject.com/blog/2010/03/24/2008-2006-2000-and-1971-data-updated/ Just a quick note to document a few changes to the database where the SPC has modified data for past years:

A number of changes were made to 2008 records:

As a result of the modifications to 2008 data, the count of tornadoes for the year is now 1690 (from 1689), while the total count since 1950 is 53254 (from 53253.)

]]> http://www.tornadohistoryproject.com/blog/2010/03/24/2008-2006-2000-and-1971-data-updated/feed/ 0 2009 SPC Data Added http://www.tornadohistoryproject.com/blog/2010/03/22/2009-spc-data-added/ http://www.tornadohistoryproject.com/blog/2010/03/22/2009-spc-data-added/#comments Tue, 23 Mar 2010 03:36:02 +0000 admin http://www.tornadohistoryproject.com/blog/2010/03/22/2009-spc-data-added/ I am pleased to announce that 2009 tornado data has been added to the database. 1,156 tornadoes were added this year, bringing the total number of tornadoes in the database to 53,253. Just visit the front page to get started.

Note that, at the time of writing, the SPC has not assigned sequential national or state tornado numbers. However, they are using temporary non-sequential tornado numbers for the national number, which has been carried over here. Once the SPC officially sequences the tornadoes, our data will be updated.

]]> http://www.tornadohistoryproject.com/blog/2010/03/22/2009-spc-data-added/feed/ 0 2006 and 2007 data updated http://www.tornadohistoryproject.com/blog/2009/10/12/2006-and-2007-data-updated/ http://www.tornadohistoryproject.com/blog/2009/10/12/2006-and-2007-data-updated/#comments Tue, 13 Oct 2009 01:41:09 +0000 admin http://www.tornadohistoryproject.com/blog/2009/10/12/2006-and-2007-data-updated/ In a previous post, I noted that there were some significant revisions to the 2006 and 2007 SPC historical tornado archive (the source of data for this site.)  According to Gregorgy Carbin, the Warning Coordination Meteorologist at the SPC, the National Weather Service changed the way they reported latitude and longitude values in October of 2006.  The person responsible for maintaining the SPC archive at the time inadvertently continued to convert the lat/lon values from minutes/seconds to decimal degrees, even though they were now being reported by the NWS in decimal degrees.  This unnecessary conversion caused the lat/lon values to be slightly off.  When this was discovered in late 2008, he corrected the lat/lon values, while also taking the opportunity to do some additional quality control.

As of last Saturday night (10/10/2009), these changes have been incorporated into the Tornado History Project database.  Although not a comprehensive list, some key changes are listed below:

* Index numbers are generated by the Tornado History Project to uniquely identify tornadoes within the site. The index number is not part of the official SPC data.

]]> http://www.tornadohistoryproject.com/blog/2009/10/12/2006-and-2007-data-updated/feed/ 0 2008 SPC Data Added http://www.tornadohistoryproject.com/blog/2009/08/06/2008-spc-data-added/ http://www.tornadohistoryproject.com/blog/2009/08/06/2008-spc-data-added/#comments Thu, 06 Aug 2009 23:13:12 +0000 admin http://www.tornadohistoryproject.com/blog/2009/08/06/2008-spc-data-added/ I am pleased to announce the addition of the 2008 tornado data from the Storm Prediction Center (SPC). Simply go to the search page to have a look.

I should note that the SPC has not assigned state tornado numbers this year (as of the time of writing.) Although a minor issue, this does affect how tornado index numbers* were chosen for tornadoes. In past years, the index number was generally a mix of the date, state FIPS code, and state tornado number (see “2006 Data Added to Tornado History Project Database”. However, since the state tornado number has not yet been assigned, the general SPC tornado number was used instead.

One more note on the archive files posted by the SPC this year…I noticed some significant revisions to the 2007 and 2006 data (mainly tornado number and latitude/longitude revisions), but those changes have not yet been incorporated here. So, be on the lookout for another update to address this in the near future, as well as several other general updates to the Tornado History Project.

* Index numbers are generated by the Tornado History Project to uniquely identify tornadoes within the site. The index number is not part of the official SPC data.

]]> http://www.tornadohistoryproject.com/blog/2009/08/06/2008-spc-data-added/feed/ 0 The SPC Archive and the Tornado History Project http://www.tornadohistoryproject.com/blog/2008/07/23/the-spc-archive-h/ http://www.tornadohistoryproject.com/blog/2008/07/23/the-spc-archive-h/#comments Thu, 24 Jul 2008 02:41:09 +0000 admin http://www.tornadohistoryproject.com/blog/2008/07/23/the-spc-archive-h/ One of my favorite recently added features of the site (see Major Upgrade to Tornado History Project 7/19/08) is the ability to easily correlate each tornado in the Tornado History Project database to the original line (or lines) in the Storm Prediction Center (SPC) archive. Why is this important? It is not uncommon for users to email me with a comment such as:

The county listed for tornado X is wrong. It should be Y – I know because it hit my house. Why don’t you do a little research before putting this on the internet?.

Yikes! While I want to know when there is a suspected error in the data, I also want to be clear where the information comes from. So, this will make it much easier to tell if the Tornado History Project is accurately reporting the data as given in the original SPC archive. In short, it adds transparency to the site and takes the mystery out of where the data comes from. And in cases where the Tornado History Project has changed any of the data (which is very rare), notice is given.

Let’s take a look at where you can find this info. On any individual tornado map page, all stats for that tornado are shown in an easy to read format immediately under the map as shown in the picture below. The last line of the section shows the actual text from the SPC archive used to generate those stats.

Of course, being able to actually see the original line from the SPC archive isn’t quite enough. It is also important to know how to read and interpret the information. So, a link is also given to the SPC instructions that explains what each piece of information actually means.

I should point out that there is one situation in which the approximate path shown for a specific tornado may not actually be based on the data in the SPC archive. Please see a previous blog entry (Enhanced Paths Explained 7/19/08) for more information.

And finally, there is one more note on this…Users must be logged in to see the corresponding line (or lines) from the SPC archive, so if you don’t see anything it, just login or register for a free account and you’ll be all set.

]]> http://www.tornadohistoryproject.com/blog/2008/07/23/the-spc-archive-h/feed/ 0 Enhanced Paths Explained http://www.tornadohistoryproject.com/blog/2008/07/19/ncdc-enhanced-path-data-what-is-it/ http://www.tornadohistoryproject.com/blog/2008/07/19/ncdc-enhanced-path-data-what-is-it/#comments Sat, 19 Jul 2008 20:32:39 +0000 admin http://www.tornadohistoryproject.com/blog/2008/07/19/ncdc-enhanced-path-data-what-is-it/ One of the most exciting new features of the site (see Major Upgrade to Tornado History Project – 7/19/2008) is the inclusion of enhanced path data derived from the National Climatic Data Center (NCDC) historical archive (thanks to Stuart Hinson for providing access to the archive!) While there are many differences between the Storm Prediction Center (SPC) historical archive (the primary source for the site) and the NCDC archive, the most significant difference is the method used to give coordinates.

In a nutshell, for tornadoes in which path data is available, the NCDC archive gives latitude and longitude coordinates when a tornado enters another county, while the SPC archive only gives coordinates when a tornado enters another state. This means that multi-county tornadoes in the NCDC database may have more data points available to draw a more detailed approximate path on the map. Thus, instead of the straight lines generated for SPC derived paths, NCDC derived paths generally have more turns and zig-zags.

How big of a difference does the inclusion of NCDC data make? Well, that depends on the number of NCDC derived data points given for any specific tornado, but let’s look at an example. The screenshot below shows a few F5 tornado paths using SPC data. As you can see, the approximate paths are straight lines, except for where a tornado crosses a state line.

The screenshot below shows the same area using NCDC derived data, when available. As you can see, some of the paths show a greater amount of detail.  Compare the apparent path near Jackson, Mississippi, for example.  With the enhanced path data below, the path passes the city from the South rather than the North.  And the more you zoom in, the more the difference will become apparent.

Displaying enhanced path data was not an easy task and took me almost a year to complete. The main issue was that there was no easy way to match up the tornado records between the two historical archives. I had to do quite a bit of manual tweaking to get it to work. Nevertheless, I think it was well worth the effort. I haven’t done an exact count, but I estimate that there are roughly 2,000-3000 tornadoes with enhanced path data, out of the 50,000 tornadoes in the database (the vast majority of tornado paths are short and only affect a single county.) Please note that you can only see enhanced path data when you are logged in.

I believe this to be the first time anything like this has been done. If someone knows different, please let me know. In any case, I hope you will sign up and do your own tornado search.

]]> http://www.tornadohistoryproject.com/blog/2008/07/19/ncdc-enhanced-path-data-what-is-it/feed/ 2 Major Upgrade to Tornado History Project http://www.tornadohistoryproject.com/blog/2008/07/19/major-upgrade-to-tornado-history-project/ http://www.tornadohistoryproject.com/blog/2008/07/19/major-upgrade-to-tornado-history-project/#comments Sat, 19 Jul 2008 19:35:42 +0000 admin http://www.tornadohistoryproject.com/blog/2008/07/19/major-upgrade-to-tornado-history-project/ It has been a long time coming and is long overdue, but I have finally released a significant update to the Tornado History Project. For those who have been here before, the first thing you might notice is a change to the general look of the site. In short, it just looks better. But that is minor compared to the new features. I’ll post more in-depth details on some of the new features later, but the major ones include:

  • Historical data extended through 2007
  • A user account system
  • Enhanced tornado path data for select tornadoes (see Enhanced Paths Explained 7/19/2008)
  • Ability to correlate any tornado with the related line in the original SPC archive
  • Ability to export custom data searches
  • New buttons on the map, including experimental integration with Google Earth
  • Improved functionality in the tornado forums (there are over 50,000 forums available.) Improvements include:
    • Immediate posting of user comments (no need to wait for them to be approved)
    • Ability to watch any tornado forum for comments
    • A user ranking system (F0 through F5)
  • Other minor improvements

While these improvements are important, their real value is that they are the necessary foundation for future development. Keep checking back as I hope to improve the site even further. And remember, the purpose of this site is to recreate the history of as many tornadoes as possible through eyewitness accounts, personal memories, photos, and videos. I can’t do that alone – I need your help. So, tell your friends about this site, post your own memories or photos and videos, and, if you can, make a small donation.

]]> http://www.tornadohistoryproject.com/blog/2008/07/19/major-upgrade-to-tornado-history-project/feed/ 2 2004 Time Errors fixed http://www.tornadohistoryproject.com/blog/2008/05/09/2004-time-errors-fixed/ http://www.tornadohistoryproject.com/blog/2008/05/09/2004-time-errors-fixed/#comments Sat, 10 May 2008 02:44:14 +0000 admin http://www.tornadohistoryproject.com/blog/?p=7 It recently came to my attention that the time given for tornadoes occurring in 2004 was incorrect. The root of the problem is that the time as given in the source data (SPC historical archive) are in a different format for 2004 than in all other years. Thus, the standard translation used for all other years does not work for 2004. To make a long story short, the Tornado History Project database has been updated with corrected 2004 tornado times.

]]> http://www.tornadohistoryproject.com/blog/2008/05/09/2004-time-errors-fixed/feed/ 2 Searches Now Easier Than Ever http://www.tornadohistoryproject.com/blog/2008/02/10/searches-now-easier-than-ever/ http://www.tornadohistoryproject.com/blog/2008/02/10/searches-now-easier-than-ever/#comments Mon, 11 Feb 2008 00:16:02 +0000 admin http://www.tornadohistoryproject.com/blog/?p=6 The latest update to the Tornado History Project has made searching for tornadoes easier than ever. Previously, there were separate pages for searching the database and outputting the results on a map or in a table. So, if you were viewing the search results in table form, but wanted to view the same search on a map, you had to 1) go to the map page – which erased your previous search parameters 2) re-enter your search parameters 3) submit your search. Now, a user can simply use the combined search page and toggle between the map and table outputs.

Also, in previous posts I have mentioned that improved path data was forthcoming for selected tornadoes. This is still in the works, but has not yet been completed. I will post here when it is ready to go.

]]> http://www.tornadohistoryproject.com/blog/2008/02/10/searches-now-easier-than-ever/feed/ 1 2006 Data Added to Tornado History Project Database http://www.tornadohistoryproject.com/blog/2007/10/24/2006-data-added-many-other-updates-too/ http://www.tornadohistoryproject.com/blog/2007/10/24/2006-data-added-many-other-updates-too/#comments Wed, 24 Oct 2007 22:54:06 +0000 admin http://www.tornadohistoryproject.com/blog/?p=5 The 2006 data has finally been added! I know I initally said I’d be done with the 2006 update by the end of September, but it proved to be more difficult than I had anticipated. Well, actually, getting the data added wasn’t the difficult part – it was the near complete internal database reorganization I decided to do. To make a long story short, there are several inconsistencies within the SPC archive. I’m not talking about errors in the data such as incorrect Fujita classificaions, lat/lon coordinates, etc. (there are still many of those…), but rather, inconsistencies with how segments of the data relate to one another. I have identified most, if not all, of the inconsistencies and have made modifications where needed. The modifications were generally limited to the internal SPC numbering scheme (the “SPC Tor. #” and “State Tor. #” columns on the Tornado Database page) and do not affect the official stats such as locations, fatalites, injuries, etc. Any modified records will be displayed in a red font when viewing search results on the Tornado Database page.

Also, significantly, I have completely changed the internal tornado indexing scheme. This shouldn’t affect anything, but it is an important change in that the new index will serve to permanently identify tornadoes in the Tornado History Project database going forward. The index is derived by combining the date of the tornado, the FIPS code of the state it occurred in (or the first state it occurred in if it is a multi-state tornado), and the state tornado number of that tornado. So, a tornado that occurred on 1/1/1950 in Alabama (FIPS code=1) and has been given the state tornado number label of 1 by the SPC will become tornado index #19500101.1.1
In addition to internal database changes, I have made the site somewhat easier to use (I think…) by providing clearer instructions and more appropriate icons representing links to maps, user comments, photos, and videos. You can see this by taking a look at the Tornado Database page. Tornado paths have also been changed to match the color of the tornado icon. So, an F3 tornado is now represented by the old orange icon and the new orange path line (instead of a standard blue path line…)

A few other changes were made too, but probably not significant enough to discuss here. Keep checking back over the next few weeks/months as I have a few other updates planned. The biggest update will be adding more detailed path data for many tornadoes (see previous blog post for more information.

]]> http://www.tornadohistoryproject.com/blog/2007/10/24/2006-data-added-many-other-updates-too/feed/ 1 SPC Adds 2006 Tornado Data to Historical Archive http://www.tornadohistoryproject.com/blog/2007/08/29/spc-adds-2006-tornado-data-to-historical-archive/ http://www.tornadohistoryproject.com/blog/2007/08/29/spc-adds-2006-tornado-data-to-historical-archive/#comments Wed, 29 Aug 2007 22:26:00 +0000 admin http://www.tornadohistoryproject.com/blog/?p=4 The SPC (Storm Prediction Center) has recently added 2006 data to their historical tornado archive . A quick glance through the documentation reveals 2 new data elements have been added:

  • Pl – A categorization of path length calculated as Pl=2*log(Length) + 1
  • Pw – A categorization of path width caculated as Pw=2*log(Width) + 5

Additionally, 2 data elements present in past releases have been removed:

  • DPI (Destruction Potential Index)
  • Code (the meaning of this element was unknown)

Over the next few weeks I’ll be comparing the 2006 file with the 2005 file to see if any changes have been made to past (pre 2006) data. Once everything is squared away, I’ll add 2006 data to the TornadoHistoryProject website. Hopefully, this will be done by the end of September (or before), so keep checking back.

I have also obtained a separate historical archive from the NOAA (National Oceanic and Atmospheric Administration) that includes more detailed path information for multi-county and multi-state tornadoes (I am not yet sure of the derivation of this archive; I’ll post more when I have more information…) Essentially, lat/lon coordinates are given when a tornado passes from one county or state to another. This will result in a more accurate representation of tornado paths (particularly for long paths.) Having said that, there are a number of discrepancies between the two historical archives that need to be resolved. I may end up adding the expanded path data in separate year by year releases as each year’s data is cross-checked between the two databases. However I do it, this will definitely be a labor intensive project so it may take a while to fully complete it. I’ll post more details as I go along.

]]> http://www.tornadohistoryproject.com/blog/2007/08/29/spc-adds-2006-tornado-data-to-historical-archive/feed/ 1