State of the Chase Season: 2016 Edition

[TJ Schulte]

Mid May does look good as troughing will return to the Plains along and we all know the heat and humidity really get kicking in by then.

I'll tell you as an Ohio resident this blocking pattern has been awful. Grey and cool weather everyday

 

[Manuel Salgado]

The CFS dashboard is looking like things pick up after the next 10 days or so, so I'm hopeful.

 

[Jeff Duda]

I think the GFS has done fairly well so far this year. I haven't seen any major busts on its part from forecasts within about 100 hours. Keep in mind that the GFS never fully said a tornado outbreak was going to happen last week. Some people just saw a negatively tilted trough with some moisture and way overreacted.

Synoptic scale forecast skill typically becomes pretty poor after 7-10 days, so yeah, I wouldn't trust any forecast out past about hour 168, and in many cases there are still large changes to the pattern in a forecast between 120 and 168 hours. Personally, I see no reason to think we won't be looking at a double cutoff with a high amplitude ridge over the central US by mid-late this week. I'm not sure I would go as far as to call it an omega block since it only persists for about 4 days in the large scale models and ensembles (although the 00Z FIM tries to construct a Rex block over the Rockies, so the western cutoff persists much longer in that model). Depending on how the western cutoff evolves as it starts to move on, there may be a possible setup next weekend, but I wouldn't hold my breath. Even if something materialized, I'm guessing it would again be messy.

Agree with Taylor and James in that this year has pretty much sucked a fat one outside of April 15th, which I'm glad I chased. The structure this past Thursday was nice, but it couldn't have occurred in crappier terrain. I was wrong about March being an active month in the Plains, and with April being so dead, I really don't know what to expect from May. Climatology is on our side now, but the actual weather rarely matches climatology on any given day. It always seems the second half of May offers some decent action, so hopefully that will make the season for us "southern" chasers who can't really get up north of I-80 regularly come June and July.

 

[Ben Holcomb]

I don't think anything can be as bad as 2014. Minus the 4/27-28 event out east and those 3 days I couldn't chase in June it was a pretty miserable year in April-May-June. I'm not hitting the panic button yet, but Jari (my friend from Finland) is going to be mighty bored starting Friday when he arrives if things don't change in a hurry.

Sent from my XT1254 using Stormtrack mobile app

 

[Brett Roberts]

The overall chase quality of March-April this year on the Plains was borderline abysmal, by most measures. April 15 was the lone bright spot. I don't think any other day has even been worth remembering, either for tornadoes or structure, to be honest.

Looking at the mean 500 mb height anomalies for March-April, there were two dominant midlatitude cyclones on our side of the globe: one south of the Aleutians, and the other over Hudson Bay (eastern Canada). In between, a strong and persistent ridge has been in place over western Canada all spring, much like last year. Any western troughs we've seen have tended to result from energy breaking off the Aleutians trough and undercutting the Canadian ridge. This generally means cutoff lows, or at least systems that are tending to weaken as they eject from the Rockies. On the plus side, this has led to a lot of rain for the Plains the past few weeks, which helps our late-season prospects. But it also has led to flawed synoptic setups, particularly with regard to directional shear in the warm sector.

Based on persistence, medium-range guidance, and the strongly positive PDO, I'm skeptical that the western Canada ridge will leave the picture anytime soon. In conjunction with the downstream eastern NA troughing it tends to encourage, this may make high-end outbreak scenarios more difficult to come by than average, but you never know. This general configuration of western US troughs tending to undercut higher-latitude ridging is pretty similar to last spring, in a broad sense. If that pattern continues (I'm certainly not saying that it will, as seasonal forecasting is not my area), we could end up with a ton of marginal/borderline days with diamonds in the rough, as we generally saw from early May to early June last year. Having good evapotranspiration thanks to recent rainfall should mean that all it takes is modest W or SW flow over portions of the Plains any given day to have a chance (e.g., the Canadian day), even if ominous full-latitude troughs prove hard to come by. Just trying to look for silver linings here, hard as it is lately...

 

[John Wetter]

The CFS dashboard from the SPC and the CFS ensembles on the HopWRF site are looking pretty positive for the last week of May and first week of June. Here's to hoping something comes along! The next couple weeks look really quiet so we can all dig in at work and get things done so we can start leaving early and taking vacation come June... Or maybe that's just me. ;-) I am optimistic though looking at the long range stuff as a signal seems to be developing.

 

[Andy Wehrle]

The CFS dashboard from the SPC and the CFS ensembles on the HopWRF site are looking pretty positive for the last week of May and first week of June. Here's to hoping something comes along! The next couple weeks look really quiet so we can all dig in at work and get things done so we can start leaving early and taking vacation come June... Or maybe that's just me. ;-) I am optimistic though looking at the long range stuff as a signal seems to be developing.

My vacation is booked for that week, so that works for me.

 

[chrisbray]

Despite the east coast troughing, next weekend into early next week doesn't look too shabby on the last few GFS runs. Let's see how this plays out

 

[Jeff Duda]

Despite the east coast troughing, next weekend into early next week doesn't look too shabby on the last few GFS runs. Let's see how this plays out

Veer-back.

Next setup, please!

 

[Brandon Centeno]

Veer-back.

Next setup, please!

Yeah, I've had enough of messy storms as a result of veer-back. No thanks!

 

[Quincy Vagell]

We're moving into the often "oddly quiet" first week of May. Yes, I know, the early part of May has featured high-end outbreaks in the past, but it's also had its fair share of dull days. Aside from a few stray days (particularly last May 6), early May has been generally weak for chasing since 2011. It was rough in '04 and '05 too.

In fact, between 2004 and 2015, 55% of days between May 1-7 reported two or less tornadoes. A total of 35% of those days had no tornadoes at all:


There are some signs of an uptick in severe potential this weekend with the next trough ejection and although this pattern is better than it would otherwise be if it were earlier in the season, seeing a big trough in the East at the same time leads me to believe it may be a relatively messy setup. How long will we go without any true high-end events?

 

[JamesCaruso]

The CFS dashboard from the SPC and the CFS ensembles on the HopWRF site are looking pretty positive for the last week of May and first week of June. Here's to hoping something comes along! The next couple weeks look really quiet so we can all dig in at work and get things done so we can start leaving early and taking vacation come June... Or maybe that's just me. ;-) I am optimistic though looking at the long range stuff as a signal seems to be developing.

That would be perfect for me, I was going to take my two week chase vacation starting May 14 or 21, but the 21 would be better relative to other commitments here at work/home so I hope you and the CFS are right!

 

[James Gustina]

We're moving into the often "oddly quiet" first week of May. Yes, I know, the early part of May has featured high-end outbreaks in the past, but it's also had its fair share of dull days. Aside from a few stray days (particularly last May 6), early May has been generally weak for chasing since 2011. It was rough in '04 and '05 too.

In fact, between 2004 and 2015, 55% of days between May 1-7 reported two or less tornadoes. A total of 35% of those days had no tornadoes at all:
View attachment 13264

There are some signs of an uptick in severe potential this weekend with the next trough ejection and although this pattern is better than it would otherwise be if it were earlier in the season, seeing a big trough in the East at the same time leads me to believe it may be a relatively messy setup. How long will we go without any true high-end events?

Outside of May 2007 I can't really think of a year that had a solid first week of May. I tend to expect it to be the transition period and it seems this year isn't going to be much different sadly, given how slow it's been.

 

[Greg McLaughlin]

The first ten days of 2003 experienced record tornado activity. That and 2007 are the only two active stretches in early May I can recall. Most of the tornadoes I have seen have occurred during the final two weeks of May.

 

[Josh Frank]

Another strong first week of May is 1999 with the Oklahoma outbreak. Also I think 1995 had a big first week too.