Thoughts about the upcoming 2015 chase season

Check out the latest GFS. I've never seen the southern branch forecast to dip down into the equatorial region of the northern hemisphere. I can't ever recall seeing a trough dig/develop that far south in latitude before. We'll see if it verifies or not, but definitely one very bizarre upper air pattern if it does. Anybody else ever see anything like this?

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I just finished up covering that in the weather discussion at the NWC. I can't recall seeing a forecast like that before. That's also an extreme example of a split-flow pattern or even a rex block, with a big ridge over the top of that in the polar jet. That's really blocky since there's almost no zonal flow anywhere in that latitude band (from near 0 degrees to 50-60 degrees N) across the Rockies/plains, so everything is going to be moving north/south with that pattern. Doesn't look like a ton of precip coming to the Plains region with that trough either. The FIM makes it more of a cutoff that parks it over AR/LA/MS. Unforunately that is the wrong place for a cutoff to sit in order to get replenishing rains across the southern plains. Sad to say it, but I don't see any indications of the drought waning through the next 2 weeks and probably beyond that. It also doesn't appear there will be any large-scale support for severe weather anytime soon either. There may be something in Dixie alley, but it's still really far out to say anything for sure.

By the way, happy El Nino, everyone! http://www.climate.gov/news-features/blogs/enso/march-2015-enso-discussion-el-niño-here
 
We get caught in that massive area of subsidence on the rear of it while it spins over Dixie it looks like. With temps rising heading into next week, most of the S. Plains will probably dry out before the next front which is no bueno.
 
Don't come down on me hard, but I think this is climate change.

We've seen an unusual number of extreme jet stream patterns like this (massive ridges and troughs) in the past fifteen years, which happens to coincide with the period of time scientists have been observing record loss of summertime Arctic sea ice and record retreat of springtime snow cover in the Arctic. Scientists and myself wonder if it's possible that these changes in the Arctic are causing the wild jet stream behavior of recent years. If Arctic changes are truly to blame for the extreme jet stream behavior, losing the remaining 50% of Arctic sea-ice coverage between now and 2030 will bring even greater extremes. If the Arctic is not involved, that is worrisome as well, because that means jet stream changes are due to an unknown cause, leaving scientists with no idea how the jet stream will respond as climate change progresses. Therefore, my thoughts for the future years: expect the unprecedented.

And who knows how storm chasing will be affected!
 
Don't come down on me hard, but I think this is climate change.

We've seen an unusual number of extreme jet stream patterns like this (massive ridges and troughs) in the past fifteen years, which happens to coincide with the period of time scientists have been observing record loss of summertime Arctic sea ice and record retreat of springtime snow cover in the Arctic. Scientists and myself wonder if it's possible that these changes in the Arctic are causing the wild jet stream behavior of recent years. If Arctic changes are truly to blame for the extreme jet stream behavior, losing the remaining 50% of Arctic sea-ice coverage between now and 2030 will bring even greater extremes. If the Arctic is not involved, that is worrisome as well, because that means jet stream changes are due to an unknown cause, leaving scientists with no idea how the jet stream will respond as climate change progresses. Therefore, my thoughts for the future years: expect the unprecedented.

The AMS and other weather/climate agencies have been putting more focus over the past few years now trying to determine if many extreme events are related to climate change or natural variability. For most events (the current California drought is one such event), the findings are that these extreme events are mostly just natural variability within the climate system, or "noise" on the "signal". True climate change implies the event occurred because the signal has changed. While there's great consensus among the scientific community that the the global climate is changing, the change is very slow and gradual. You really shouldn't expect to be seeing extreme events occurring regularly as a direct result of climate change at this point in time. We won't really be seeing those until closer to the end of the 21st Century.

I don't think this pattern is the direct result of climate change. Rather I think it's just a sh!tty pattern associated with winter. It happens every now and then. Spring will eventually arrive and so will the troughs. It just may not be as early as in years like 2012.
 
If the current models hold up, I expect the fire threat in Central OK to go up considerably by Tuesday of next week. We've been lucky for the most part this winter; the only major wildfires we had were in January. I'm grateful for the lack of wildfires, but I don't see it lasting very long if the projected dry spell verifies...

A repeat of 2013, with a relatively wet late spring and summer, would really help in this regard. I was still in TN in 2011, but I don't recall any major wildfire issues back home in OK that year either. This winter more resembles 2010-2011 (albeit less precip this winter) than it does 2012-2013, but I'll take anything to keep the wildfires down. I'd love to have the time to do some more research on correlations between precipitation during a winter and the following storm season. My memories growing up make me think there is a correlation, but I really need to look at the hard data from those years.

Jeff,

I've read of some that have theorized that the last century and a half or so of relatively moist weather in California is actually outside of the norm, and the dryer climate is actually more of the norm. It makes sense considering the currents of the Pacific tend to head out to sea at that latitude (as opposed to everything headed onto land in the Pacific Northwest), and Eastern Pacific hurricanes veer towards the west if they go north of the Baja Peninsula. It's also interesting to note that there were vineyards as far north as England during the Middle Ages. That seems to be indicative of a warmer climate during that period. It would be fascinating to see what the data shows in another 500 years of solid record keeping. The geek in me wants to say that the data we have is entirely too small of a sample to really draw any conclusions. I would venture to say that records would have to go back another 3-500 years to really understand the long-term fluctuations.

I would agree with the consensus that climate is changing, but I firmly believe that climate has been changing constantly over the entire history of the Earth. I'm not sure if it's even possible for the climate to remain the same (relatively speaking) over the course of a few centuries, let alone millennia. My gut says it's not possible, which seems to go against human tendency to resist change, as opposed to going with the flow.
 
The AMS and other weather/climate agencies have been putting more focus over the past few years now trying to determine if many extreme events are related to climate change or natural variability. For most events (the current California drought is one such event), the findings are that these extreme events are mostly just natural variability within the climate system, or "noise" on the "signal". True climate change implies the event occurred because the signal has changed. While there's great consensus among the scientific community that the the global climate is changing, the change is very slow and gradual. You really shouldn't expect to be seeing extreme events occurring regularly as a direct result of climate change at this point in time. We won't really be seeing those until closer to the end of the 21st Century.

I don't think this pattern is the direct result of climate change. Rather I think it's just a sh!tty pattern associated with winter. It happens every now and then. Spring will eventually arrive and so will the troughs. It just may not be as early as in years like 2012.

Jeff, I would love to talk more about this subject.

So you're saying that almost anything we're seeing now (except global temperature rise over a month or longer) is basically noise? That the jet stream activity which some theorize to be influenced by a reduction of arctic sea ice is still, at this point, almost definitely just noise? What about the "supposed" other changes like increase of extreme precipitation events? Is every climate extreme weather event we are seeing at this point something that can just happen and does happen without the influence of a changing climate? What about all the beetle outbreaks killing trees all over the world? The amazonian drought (I guess that's probably the result of deforestation)? Precipitation reduction in Hawaii due to "changing" trade winds?

Drew, it's interesting what you say about how people theorize that CA is normally more dry than it has been in recent decades. Do you know if there are any thoughts on other parts of the country? Are certain places actually wetter than we currently believe they are?
 
Regarding climate teleconnections and US weather:

El Nino is very weak at present (although there is evidence of a 'Modoki' El Nino, Central Pacific warming), the PDO (Pacific Decadal Oscillation) is very positive at the moment and has been the strongest driver of US climate for at least the last year (it favours western ridge/eastern trough, not favourable for severe weather in the Plains overall). I think there is a weak correlation between El Nino and early season tornadoes in Oklahoma, but the links are weak at best. The strongest one I've read about is the link between a strong La Nina and violent tornado outbreaks.
 
Just a tidbit of info for you guys. Talked to the WCM at the Amarillo NWS today, and she informed me that Dalhart, TX is 20 inches above normal on snowfall for the year! That surprised me. I believe she said they have received 32 or 34 inches so far. Not bad!
 
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