68 replies to this topic

[andyhb]

Following suit with last year's thread, how many of these things do you think we'll see this year?

I'm gonna go with around 1375 right now.

[iowahawkeyedave]

I'm going to go with 1600. Think it's going to be another active year, let's just hope they all stay out in open land this year though.

[tornadotony]

I'm going to go with a much quieter year. 1050.

[JoMo]

I'm going to go with a much quieter year. 1050.

Any particular reason?

[tornadotony]

Any particular reason?

Mostly anecdotal. Second-year Niñas, especially those weaker than the previous winter's or those coming off of ones associated with big tornadoes seasons (so years like 1975 and 2000) have not historically been active tornado years. Additionally, instability is obviously one of the core factors of severe thunderstorm formation, and abnormally unstable airmasses were the hallmark of 2011, especially the April events (5000J/kg CAPE in Iowa with the violent tornadoes of 9 April, for example). With the lack of cold air in this part of the world, I question how cold we will be aloft with systems this spring and how unstable the coincident warm sectors will be. Moisture won't likely be an issue; in fact, it may be in slightly better supply than even last spring. But what will mid-level lapse rates be for potential severe wx systems? That's the big question.

A couple other thoughts on spring 2012. Given the unseasonable warmth and La Niña conditions, I expect an early start to the season. How early remains to be seen. Also, with the general lack of cold air, I feel the air of greatest threat this spring, whereas it was over the southeast last spring, will be shifted NW to include the lower Lakes, mid-MS valley, and central/southern Plains, with cities like Tulsa, Springfield, St. Louis, Kansas City, Davenport, Des Moines, Chicago, and Indy being the more favored areas for activity. Finally, though I expect a much quieter season overall, I would not at all rule out a bangup event or two, especially in the aforementioned areas and especially early in the season, say late-Feb or March.

Of course, we can't really accurately predict a severe wx event the day of, so this is all really just rambling.

[Stebo]

I think 1375 is a good number, I think it will be less active too this year but I am hedging my bets that it stays near normal to slightly above activity.

[Hoosier]

1396

[AcworthWx]

Mostly anecdotal. Second-year Niñas, especially those weaker than the previous winter's or those coming off of ones associated with big tornadoes seasons (so years like 1975 and 2000) have not historically been active tornado years. Additionally, instability is obviously one of the core factors of severe thunderstorm formation, and abnormally unstable airmasses were the hallmark of 2011, especially the April events (5000J/kg CAPE in Iowa with the violent tornadoes of 9 April, for example). With the lack of cold air in this part of the world, I question how cold we will be aloft with systems this spring and how unstable the coincident warm sectors will be. Moisture won't likely be an issue; in fact, it may be in slightly better supply than even last spring. But what will mid-level lapse rates be for potential severe wx systems? That's the big question.

A couple other thoughts on spring 2012. Given the unseasonable warmth and La Niña conditions, I expect an early start to the season. How early remains to be seen. Also, with the general lack of cold air, I feel the air of greatest threat this spring, whereas it was over the southeast last spring, will be shifted NW to include the lower Lakes, mid-MS valley, and central/southern Plains, with cities like Tulsa, Springfield, St. Louis, Kansas City, Davenport, Des Moines, Chicago, and Indy being the more favored areas for activity. Finally, though I expect a much quieter season overall, I would not at all rule out a bangup event or two, especially in the aforementioned areas and especially early in the season, say late-Feb or March.

Of course, we can't really accurately predict a severe wx event the day of, so this is all really just rambling.

My guess is 985.

Very well thought out points, Tony. I too think it won't be as active of a season this year. Mainly because of the lack of cold this winter. I don't necessarily think it will be an early season, which is another big point of me going lower with my guess, but like you said it is more of rambling than anything.

[andyhb]

My guess is 985.

Very well thought out points, Tony. I too think it won't be as active of a season this year. Mainly because of the lack of cold this winter. I don't necessarily think it will be an early season, which is another big point of me going lower with my guess, but like you said it is more of rambling than anything.

If we get the cold to drop down later in the winter into the early/mid spring like some of the forecasts/models suggested in the pre-winter outlooks, then that would open the door for some significant events.

As for high risks, I'm gonna go with 3-5 days, with 2-4 in March/April/May/June and 1 outside of those months.

As an analog in terms of high risks, last year had 5 (4/16, 4/26, 4/27, 5/24 and 5/25, although 4/15 could have easily qualified) and these all produced significant tornado outbreaks.

[thewxmann]

Agree with Tony here, but I'll go with the 10-yr average minus 2004, 2008, and 2011... somewhere ~1150 (hopefully that's close to what it is).

[knitwx]

I will say 852 . I also think there will be a major Great lakes or upper midwestern outbreak.

[Thundersnow12]

1266.

[Fred Gossage]

I think Tony, Jim,Stebo (although, I'd maybe go with a number a little lower), and Mr. Piechota all have the right idea here... and Tony laid out the reasoning quite well.

My estimated range for this year would be in the 1200s.

[Hoosier]

Sub 1000 almost seems impossible in this day and age with increased detection.

[AcworthWx]

If we get the cold to drop down later in the winter into the early/mid spring like some of the forecasts/models suggested in the pre-winter outlooks, then that would open the door for some significant events.

As for high risks, I'm gonna go with 3-5 days, with 2-4 in March/April/May/June and 1 outside of those months.

As an analog in terms of high risks, last year had 5 (4/16, 4/26, 4/27, 5/24 and 5/25, although 4/15 could have easily qualified) and these all produced significant tornado outbreaks.

4/15 actually was #2 of most active days last year. Here's the preliminary list of Top ten days for 2011.


Top Ten Tornado Days of 2011
Rank / Date / Tornadoes

• 4/27/11 226
• 4/15/11 117
• 5/25/11 111
• 4/16/11 95
• 4/26/11 86
• 4/19/11 65
• 4/04/11 64
• 5/22/11 63
• 5/24/11 53
• 4/25/11 50

[tornadotony]

4/15 actually was #2 of most active days last year. Here's the preliminary list of Top ten days for 2011.


Top Ten Tornado Days of 2011
Rank / Date / Tornadoes

• 4/27/11 226
• 4/15/11 117
• 5/25/11 111
• 4/16/11 95
• 4/26/11 86
• 4/19/11 65
• 4/04/11 64
• 5/22/11 63
• 5/24/11 53
• 4/25/11 50

That's not the right tornado count. Those are LSR counts, not tornado counts.

[AcworthWx]

That's not the right tornado count. Those are LSR counts, not tornado counts.

I did say it was the preliminary count, so they will be adjusted. They aren't LSR counts, as those are much higher. Here's where I got my data.........http://spc.noaa.gov/...al_summary.html

Is there somewhere else I should be looking? I just don't know where to look for any finalized counts. Thanks for any help you can provide.

[tornadotony]

I did say it was the preliminary count, so they will be adjusted. They aren't LSR counts, as those are much higher. Here's where I got my data.........http://spc.noaa.gov/...al_summary.html

Is there somewhere else I should be looking? I just don't know where to look for any finalized counts. Thanks for any help you can provide.

Nope, those are LSRs. You need to go through Storm Data and construct paths for each day to get the actual tornado tally until SeverePlot on SPC is updated.

[AcworthWx]

Nope, those are LSRs. You need to go through Storm Data and construct paths for each day to get the actual tornado tally until SeverePlot on SPC is updated.

Thanks for the explanation, Tony.

[JoMo]

I don't know, I'm kind of worried that this crappy non-winter pattern has to break sometime and I keep thinking it may be in the Spring that we get the cold air that's been building up in Canada to finally come southward along with the supercharged jetstream which would result in more severe weather episodes. Of course I have no idea if that will happen or not.

[andyhb]

I don't know, I'm kind of worried that this crappy non-winter pattern has to break sometime and I keep thinking it may be in the Spring that we get the cold air that's been building up in Canada to finally come southward along with the supercharged jetstream which would result in more severe weather episodes. Of course I have no idea if that will happen or not.

Yeah, I mentioned this as a concern I have too.

And I am beginning to develop a hunch of one or more events in the GL/OV region this year, along with several of the other posters here.

Sub 1000 almost seems impossible in this day and age with increased detection.

Agreed strongly.

[JoMo]

http://stlouis.cbslo...ntist-predicts/

[AtticaFanatica]

No offense to him, but why are they going to Kevin Trenberth for these questions?

[Hoosier]

January has been an active month with 70 preliminary reports.

[B-Rent]

1300 +/- 75.

[cmichweather]

No offense to him, but why are they going to Kevin Trenberth for these questions?

I agree, but I do agree with his diagnosis of storm tracks carrying over into the spring but if we were to have a pattern change all that goes out the window. The ridging out in the Pac needs to chage or we'll continue to see the cutoff pattern that keeps impacting the southern plains. Also I think the drought conditions are going to play a larger factor in this years severe weather season.

[DoctorMu]

1146

I agree with Tony that the season begins early and ends early as well, leading to a robust popcorn shower season in May here in Texas.

[andyhb]

I agree, but I do agree with his diagnosis of storm tracks carrying over into the spring but if we were to have a pattern change all that goes out the window. The ridging out in the Pac needs to chage or we'll continue to see the cutoff pattern that keeps impacting the southern plains. Also I think the drought conditions are going to play a larger factor in this years severe weather season.

Looks like there might be change in the ridging coming over the next week, whether that pattern change will mean anything heading into late Winter/early Spring, that's anybody's guess.

[Indystorm]

I don't know, I'm kind of worried that this crappy non-winter pattern has to break sometime and I keep thinking it may be in the Spring that we get the cold air that's been building up in Canada to finally come southward along with the supercharged jetstream which would result in more severe weather episodes. Of course I have no idea if that will happen or not.

LaNinas can have cooler springs and a later warmup here in the Midwest at least which could support your contention. However, I am a supporter of the rubber band theory and tend to favor Tony's thinking of fewer total tors than last year's amazing record. Going with 1279 total.

[hurricaneman]

1250 but if the warm air hangs tough it could be as high as 1500 but I'm not expecting anywhere near what 2011 brought

[andyhb]

Well my guess could be well overestimated if the pattern doesn't change here...

[Ellinwood]

Well my guess could be well overestimated if the pattern doesn't change here...

Probably... patterns don't change between May and August.

[andyhb]

Probably... patterns don't change between May and August.

Uh, I meant through May, which is climatologically the peak month for tornadoes (which the current pattern for the next week or more does not support very well). I guessed 1375, which with the pattern we are currently in, seems a bit high at this point, unless June comes up big and/or the Summer (which if the ridge does hold strong like the past however many months, seems a bit unlikely, although I'm a little doubtful of another torch) or Fall (Which some of the analog/similar patterns from years past have had active seasons, 2007 and to a certain extent, 2009, for example).

That wasn't meant to draw a sarcastic remark like that...

[andyhb]

Pretty stark contrast to last year...

MAY 2012 WAS THE FIRST MAY IN 7 YEARS WITH NO FATALITIES. THE LAST
MAY WITH NO TORNADO FATALITIES OCCURRED IN 2005.

[Hoosier]

There have been 495 tornadoes confirmed through April. Last year we had 912 through April.