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Tornado season
Posted: Mon Dec 03, 2007 5:10 pm
by Cyclone1
So Hurricane season has passed, when does Tornado Season officially start? I know they can form whenever, but what's the typical range of most activity?
I've studied tornadoes since almost birth, and I've still never known this.
Re: Tornado season
Posted: Mon Dec 03, 2007 5:15 pm
by Ed Mahmoud
IIRC, along the Gulf Coast and Florida, it never really ends, and the area of maximimum frequency slowly shifts Northwards as Spring progresses. I believe I read April tends to have the deadliest tornadoes, May the most frequent, and tornado season slows greatly during the summer months as the usual jet location has generally left the country.

Posted: Mon Dec 03, 2007 5:18 pm
by RL3AO
I think Florida's peak season is January and February and then it works slowly NW until peaking in the plains in late-May early June.
Posted: Mon Dec 03, 2007 9:31 pm
by Cyclone1
Yeah, February seems right. I've never seen one, (one day...) but the majority of warnings we get here are in February.
Posted: Wed Dec 05, 2007 11:29 am
by Squarethecircle
Based on frequencies, I'd start it around the twenty fifth of February, initiate complete coverage around mid-March, and not end it until the tenth of December. That gives you two and a half months not to worry (well, you still have to worry, but not as much).
Re: Tornado season
Posted: Wed Dec 05, 2007 2:43 pm
by vbhoutex
Cyclone1 wrote:So Hurricane season has passed, when does Tornado Season officially start? I know they can form whenever, but what's the typical range of most activity?
I've studied tornadoes since almost birth, and I've still never known this.
Maybe this is obvious to all, but different areas of the country have different peak tornado seasons. I would call the most active season overall, at least based on the chart, about the same as Hurricane season, or a little shorter.
Posted: Wed Dec 05, 2007 5:23 pm
by CrazyC83
There is no tornado season. It can happen at any time of year - remember January 1999 in Arkansas? December has also had tornado outbreaks, such as one on December 24, 1982.
Posted: Wed Dec 05, 2007 5:52 pm
by Squarethecircle

So can hurricanes, but there is the Atlantic hurricane season, June to November. I believe we are trying to ascribe the same concept to tornadoes.
Posted: Wed Dec 05, 2007 6:12 pm
by Cyclone1
Yeah, I'd say typically from February to June, for the mid-west/southeast. Maybe, That's just my guess.
I was just wondering if there was an official season.
Posted: Wed Dec 05, 2007 6:16 pm
by RL3AO
There is a storm chasing season. Runs from late March to the beginning of June.
Posted: Wed Dec 05, 2007 8:42 pm
by Squarethecircle

That's rather annoying; giving up the chase after only a few months. I'd stay out until the end of July.
Re:
Posted: Thu Dec 06, 2007 6:08 pm
by CrazyC83
Squarethecircle wrote::uarrow: That's rather annoying; giving up the chase after only a few months. I'd stay out until the end of July.
In theory, you could chase year-round, but chasing in the late fall and winter months is more difficult (shorter daylight hours, different synoptics - lower CAPE, more shear).
Re:
Posted: Thu Dec 06, 2007 6:12 pm
by CrazyC83
Squarethecircle wrote::uarrow: So can hurricanes, but there is the Atlantic hurricane season, June to November. I believe we are trying to ascribe the same concept to tornadoes.
There has been only one hurricane between January and April (in 1908). And there has never been a major hurricane after the fourth week of November or before mid-May.
By contrast, there have been major tornado outbreaks in every month of the year, and F5 tornadoes in almost every month (the only ones I am aware of there never being an F5 are January and November).
Posted: Thu Dec 06, 2007 6:23 pm
by Squarethecircle

However, that does not mean there are none, and with tornadoes, the sheer frequency of them means that the "bell curve" actually looks similar to that of hurricanes.
Posted: Fri Dec 07, 2007 8:54 pm
by HarlequinBoy
But the more intense tornadoes tend to occur in Spring/early Summer rather than August-October which is the peak of Hurricane Season.
Posted: Fri Dec 07, 2007 9:22 pm
by Squarethecircle

No one said that they were in any way similar, but that the concept applies similarly to tornadoes.
Posted: Sat Dec 08, 2007 2:40 pm
by wxmann_91
The peak of tornado activity overall occurs from April to June. However, as been stated already, different areas of the country have different localized peaks; the SE US peaks in early Spring (March-April), and Fall (November), while the Northern Plains and northeast peak in Summer (June-August).
The months with the least tornado activity overall are January-February and July-September. Of course, tornado outbreaks can still occur any time of the year given the right synoptic and mesoscale setup (it's just that those setups become rather difficult to find in those months).
The ratio of intense tornadoes to all tornadoes is typically highest in early Spring (March-early May); this is also when the majority of tornado fatalities in a given year typically occur.
Re:
Posted: Sat Dec 08, 2007 8:57 pm
by CrazyC83
wxmann_91 wrote:The peak of tornado activity overall occurs from April to June. However, as been stated already, different areas of the country have different localized peaks; the SE US peaks in early Spring (March-April), and Fall (November), while the Northern Plains and northeast peak in Summer (June-August).
The months with the least tornado activity overall are January-February and July-September. Of course, tornado outbreaks can still occur any time of the year given the right synoptic and mesoscale setup (it's just that those setups become rather difficult to find in those months).
The ratio of intense tornadoes to all tornadoes is typically highest in early Spring (March-early May); this is also when the majority of tornado fatalities in a given year typically occur.
Late summer tornado activity is higher than most think, due to landfalling tropical storms and hurricanes. (Although non-tropical outbreaks are uncommon at that time of year except in the northern Plains and Great Lakes, and without the tropics that would be an inactive period).
Posted: Sun Jan 06, 2008 3:37 pm
by wall_cloud
Try the link below. It is from SPC and should give you all the climatology that you need regarding a particular area.
SPC Severe Wx Climatology
Re: Tornado season
Posted: Sun Jan 06, 2008 7:26 pm
by Ed Mahmoud
Ed Mahmoud wrote:IIRC, along the Gulf Coast and Florida, it never really ends, and the area of maximimum frequency slowly shifts Northwards as Spring progresses. I believe I read April tends to have the deadliest tornadoes, May the most frequent, and tornado season slows greatly during the summer months as the usual jet location has generally left the country.

I wonder if that little secondary spike in September is related to TC landfalls...