Predict/Guess the Number of Tornadoes and the First High Risk of 2015

[brettjrob]

I think it will have to do more with the insanely strong +PDO taking over everything, if we do get another sub-1000 season.

 

I finally decided to take a closer look at analogs with a particular focus on the PDO yesterday. Unfortunately, I have to say I've been swayed toward the concerns you've been expressing here. A strongly positive PDO (warm SSTAs along and near the Pacific coast from the Pac NW into the Gulf of Alaska) has not boded well for the Plains season in the post-1950 dataset.

 

I've created a very crude "scoring" method for Plains chase seasons for analog purposes (see here, for example) -- a composite of wintertime SSTAs for the top 10 seasons shows a strong tendency toward cold SSTAs along the northern Pacific coast, or a -PDO. An equivalent composite for the bottom 10 seasons shows a weak +PDO type signal. Worst of all, looking at individual values: none of the top 15 seasons according to my scores had a mean JFM PDO value over +0.5 (and there were 20 such cases in the dataset)!

 

We look to be on track for the highest positive Dec-Jan PDO value since at least 1950. The most recent strong +PDO was 2002-03, which of course turned out to be a fairly good spring (though not exceptional for the Plains specifically). I'm concerned though that we were in the midst of a strong Nino at that time, which certainly did not materialize this cold season. If you take out 2003, the remaining PDO > +0.8 analogs range from lukewarm to cringe-worthy. I don't necessarily think 2003 should be thrown out yet, relative to other analogs, though. Overall, I have to welcome any change in the base state from last year, but the current Pacific SSTAs sort of suggest we may be out of the frying pan and into the fire (again). All the obvious concerns about limited sample size notwithstanding, of course.

[andyhb]

I am seeing some signs that the northern part of the +PDO (NE Pacific/Gulf of Alaska) may take a hit over the next little while as a troughing regime takes over that region. Need to start breaking down that ridge piece by piece if we don't have help from STJ to undercut it.

 

Edit: I'll add on that a system like the one creating the winter storm for the GL tomorrow could do some serious damage come spring, although obviously you wouldn't want the E Pac contaminating lapse rates and it would likely be east of better chasing territory.

[OKwx2K4]

1097 tornadoes and first high risk 05-07-15

[WxBlue]

Going with 975 tornadoes and first high risk on May 3rd.

[Indystorm]

1084 tornadoes with first high risk April 9th.  Accuweather is expecting a higher number of tors for this season than in recent years with their expectations.

[andyhb]

Saw some excellent winter AO/PDO climatology from HM on Twitter earlier, actually brings some good vibes for spring considering the years mentioned that were closer matches generally played out fairly nicely in terms of overall activity (1984, 2003, 1994 and 2006, although 2006 shut down early a bit like 2012).

 

Also I saw Eric (webberweather) mention 1929 and 1930, 1930 would probably be an all-time Plains year chasing wise if it happened now.

 

Of course this isn't to say that this will carry through to spring, but analog teleconnection guidance actually has done quite well this winter from what I've seen, which is probably helped by the fact that we have such an anomalous +PDO event occurring.

[brettjrob]

Saw some excellent winter AO/PDO climatology from HM on Twitter earlier, actually brings some good vibes for spring considering the years mentioned that were closer matches generally played out fairly nicely in terms of overall activity (1984, 2003, 1994 and 2006, although 2006 shut down early a bit like 2012).

 

Also I saw Eric (webberweather) mention 1929 and 1930, 1930 would probably be an all-time Plains year chasing wise if it happened now.

 

Of course this isn't to say that this will carry through to spring, but analog teleconnection guidance actually has done quite well this winter from what I've seen, which is probably helped by the fact that we have such an anomalous +PDO event occurring.

 

My analog hunting the past week or two has turned up more discouraging results for the Plains, although I haven't looked any earlier than 1950 due to the lack of available Storm Data. Winters with CONUS temperature anomalies similar to ours so far -- with extreme warmth stretching from the Pac NW to the Northern Plains (correlated with the strong +PDO, of course) -- have not historically been kind to us.

 

This is the first year in at least a few with any clear signal in the analogs (aside from drought considerations), and that signal isn't good. Hopefully the limitations of our dataset manifest and this spring defies said signal, but gun to my head right now, I'd obviously bet against a good Plains year. 2003 seems like our main source for hope right now in the analog world; it's certainly the only of your set of post-1950 years I'd like to see play out. Others I'd throw in for consideration include 1958, 1961, 1970, 1981, and 1986. Some of those are at least around average; others (namely 1958 and 1970) are putrid.

[andyhb]

Some of those are at least around average; others (namely 1958 and 1970) are putrid.

 

Not sure how much I agree with 1970 being putrid, considering how much activity that year had in western Texas and the Panhandle.

 

Edit: the fact that the outbreak in April (17th/18th) there was at night notwithstanding...

[brettjrob]

Not sure how much I agree with 1970 being putrid, considering how much activity that year had in western Texas and the Panhandle.

 

Well, a map of all reports for the spring makes it look impressive, but all of those long-trackers in NM/TX and W OK were associated with two unusual nocturnal outbreaks (18 Apr and 30 Apr). Without trying to derail the thread too much, that's the kind of thing I tried to take into account when devising my "scoring system" for analog years linked in my post from a week or so ago -- it's more about a consistently favorable pattern and numerous tornado days. That's not to discount major events which can dramatically skew a year's tornado count or reports map all on their own, but then again, their occurrence is likely less predictable on a seasonal basis than the large-scale pattern and associated number of tornado days.

[andyhb]

Well it wouldn't be as bad as last year down that way (not saying much, I know). Hell, ICT didn't have a single tornado watch last year.

[Hoosier]

http://www.ustornadoes.com/2015/03/02/spring-2015-seasonal-tornado-outlook/

[andyhb]

And it goes on and on and on and on and on and on.....

[kevinbente]

I know it doesn't mean much, and I know this may not be the right thread for this post, but long range GFS ensembles are suggesting a more progressive pattern (finally) over the next 2 weeks. Shifting anomalous ridging to the eastern part of the US. Anomalous troughing over the rockies, spreading SW flow over the plains. Something to watch considering it's March now.

http://www.tropicaltidbits.com/analysis/models/?model=gfs-ens&region=us&pkg=z500a&runtime=2015030218&fh=12&xpos=0&ypos=182

 

And I'll go May 16th for my first high risk. 1050 tornadoes. 

[andyhb]

I know it doesn't mean much, and I know this may not be the right thread for this post, but long range GFS ensembles are suggesting a more progressive pattern (finally) over the next 2 weeks. Shifting anomalous ridging to the eastern part of the US. Anomalous troughing over the rockies, spreading SW flow over the plains. Something to watch considering it's March now.

http://www.tropicaltidbits.com/analysis/models/?model=gfs-ens&region=us&pkg=z500a&runtime=2015030218&fh=12&xpos=0&ypos=182

 

I'll believe that when it's still showing up four days out (and even then I might not fully believe it).

[kevinbente]

I'll believe that when it's still showing up four days out (and even then I might not fully believe it)

Ugh. This pattern sucks. Sorry for derailing this thread. 

[thewxmann]

Ugh. This pattern sucks. Sorry for derailing this thread. 

 

It's absolutely horrible, even in an IMBY type perspective with the drought here. We need that PDO to drop.

[Chinook]

When will be the first slight risk of March 2015?  Not too soon. None for 8 days, perhaps not for another 7.

[OKStorm]

Going with a better tornado year this year,  1235 total and the first High Risk day April 16, 2015

[Torchageddon]

Number of tornadoes in the US: 1007

First High Risk: April 22

 

Ugh. This pattern sucks. Sorry for derailing this thread. 

 

In my whole life I have never seen a pattern this atrocious for my part of the Great Lakes. I know this because I've never experienced such a concentrated period of weather I hate both IMBY and most of the continent (except some got amazing snowfall). Rotting, demoralizing, trash. The atmosphere is trying to counter-balance 2012.

[andyhb]

Pretty sure we could go all of March without a tornado in the US at this rate, which would be a first in the modern record. All of the other tornado-less months in the US were October through February. The Euro weeklies looked atrocious.

[Hoosier]

Pretty sure we could go all of March without a tornado in the US at this rate, which would be a first in the modern record. All of the other tornado-less months in the US were October through February. The Euro weeklies looked atrocious.

 

 

The record low for March is 6 tornadoes in 1951.  Most Marches have had several dozen.  IF we go the entire month without one, arguably that would be the most impressive anomaly out of anything we've seen during this relatively quiet stretch.

[Quincy]

Even looking at the Euro weeklies, would have to think California and Florida (maybe the Gulf Coast too) could see at least a few tornadoes with the increasing gradient pattern. The overall pattern isn't much different than last year, so it may not be until later in April that we see any legit shots at notable tornado events.

[Quixotic1]

1075. High risk April 24.

[brettjrob]

I hate the 2010s.

[Quincy]

Since 2005, the two seasons with near-record low tornado counts through March didn't really see much of anything until substantial events in late April. (2010 and 2014)

[1900hurricane]

Wow, I thought I already made my prediction for the year but guess I didn't. I'll go 1050 tornadoes and 1st high risk on May 1st.

 

I hate the 2010s.

 

Yeah, ugh. What a crummy timeperiod to start chasing. I keep telling myself it'll get better...eventually.

[jshetley]

It's looking like my forecast of under 500 for this will verify. It's early, but it looks as if March is gone now and maybe most of April. Could it be possible to stay under even 250 and not even a moderate risk this year?

[Hoosier]

It's looking like my forecast of under 500 for this will verify. It's early, but it looks as if March is gone now and maybe most of April. Could it be possible to stay under even 250 and not even a moderate risk this year?

 

 

Most down years have at least one high risk and who knows how many moderate risks.

[Quixotic1]

It's looking like my forecast of under 500 for this will verify. It's early, but it looks as if March is gone now and maybe most of April. Could it be possible to stay under even 250 and not even a moderate risk this year?

 

I'll take the over.  Way over.  

[andyhb]

It's looking like my forecast of under 500 for this will verify. It's early, but it looks as if March is gone now and maybe most of April. Could it be possible to stay under even 250 and not even a moderate risk this year?

 

Better start building an ark considering how much rain you want to get.