State of the Chase Season: 2015 Edition

#allaboardthehypetrain Hype train? You mean this thing?

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In all seriousness, there's good potential all next week. Capping issues on a few days. But whenever that trough decides to eject...you better be there baby!
 
I like Wednesday the most as it exhibits a very classic Plains setup. I'd probably pick the dryline near the Oklahoma/Kansas border. For Thursday, I would go eastern Kansas. But, this region struggles with backing of the winds in the upper-levels or weak upper-level shear. Not to mention the less instability overall. Of course, it's early and a lot can happen.

I can't chase either day so why am I excited anyways...?
 
I am really liking Wednesday/Thursday at the moment, but it's early April and 4-5 days out, so things could change a lot in the next few days. I admit current models have me ready to break out the Rain-X and do a multi-day trip to Kansas/Oklahoma.
 
Forecast Reality time. I posted my long term best guess based mostly on GFS data and here's how it scored. Since it's hard to get time off work, anticipating good chase days well in advance is key for me!

Monday 4/6 : Many ingredients established in the south central plains for supercells. Both GFS and NAM solutions, while NAM is more aggressive, both agree on a CAP bust or just lack of surface moisture to make it happen.

VERIFIED
Tuesday 4/7: Suffering from many of the same problems, but even then not as good of a setup overall as Monday

Partial VERIFY. Nocturnal storms produced tornadoes is SE Kansas.

Wednesday 4/8: Now things escalate quickly. Along the dryline from Del Rio to Salina, KS and along the warm front extending to Cincinnati exists the chance for severe weather including supercells. Some of the best chasing opportunities include a triple point setup around Salina. The dryline in Central Texas to OK, and possibly even southern Illinois and central Missouri as well.

VERIFIED. Triple point forecast moved to Wichita, then eventually ended up well to the west. Best storms were in N TX, W OK, and along the triple point. One tornado in Missouri near Mississippi river. LOTS of hail/wind reports in areas otherwise forecast for severe.

Thursday 4/9: Low pressure moves to Iowa area. This time the entire warm sector is in Lock and Load. Cap erodes toward late afternoon allowing convection to form in a large area from Chicago to Dallas. While mid level flow doesn't exactly scream major outbreak, it is sufficient enough that this day could move into "upper-moderate" risk territory. One dangerous scenario is the possibility of early evening or even nocturnal tornadoes over populated areas of the country. Forecast day is 5 days away and with all of the things that can happen before that, this is likely to change. Definitely commands attention however.

Partial VERIFIED. While much of this happened, the nocturnal tornado event didn't pan out. I'd like a post mortem from an expert, but it appears moisture was the factor. Still, violent tornadoes in afformentioned areas, severe from Chicago to Dallas. Overall risk category never made it past "enhanced"


Friday-Tuesday continue to show potential chase days, but too far into the future. GFS in particular has changed its mind on the location, timing, and southern extent of the front quite a few times.

BUST in progress.

...wedgefest2015 .... There was a A wedge. so maybe not.
...allaboardthehypetrain ....It was hyped for sure.


GFS? 18 days of meh.



Also, I leave you with this nugget of awesomeness from the CFS!!!!!! :p :p. 630 Forecast hour winnage.


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Last edited:
Michael G.---- Not sure why you didn't record the multiple touchdowns in SW Ks. for April 8 in your verification posts?
 

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Michael G.---- Not sure why you didn't record the multiple touchdowns in SW Ks. for April 8 in your verification posts?

I didn't specifically call that out because that was the most obvious part of the forecast. The triple point was the exact spot tornadoes were most excepted. I just wish I didn't think they would also form on the dry line :( otherwise I would have got some footage.
 
Time to revisit this thread. We had an interesting week of severe weather events, but it looks to be quiet for at least a few days now, so we have some time to sit down and evaluate the upcoming few weeks for the next threats.

We seem to be in a period of low synoptic scale predictability or just overall forecast jumpiness. Recent GFS runs have been all over the place regarding a cutoff low and eventual shortwave trough that becomes embedded within the sub-tropical jet later this week. Looks like Dixie Alley may see its first solid severe weather setup this week (although currently the details suggest the severe threat may not be on the high end like we seem to see around this time of year). There was quite a shift in the location of the cutoff between the 00Z and 12Z runs today, too, so it's a little hard to know for sure what to expect this week, other than it looks like the southern plains and southeast are going to get a drought-reducing amount of rain (when considering the amount that has fallen in the region the past few days).

After that, however, it looks kind of sad. It looks like a strong eastern US trough will form with quite low heights later in the forecast period, which will likely spill a cP air mass all over the eastern half of the country. It also appears this trough may clean out the Gulf of moisture.

Now for the good: rain, and lots of it. The southern plains has been getting a lot of rain lately. This will do wonders to keep the area from starting to bake early on once May rolls around. The rain will also help keep soil moisture up and will help with green-up so that future disturbances may give more moisture (recall the system this past week had pretty good moisture to work with: mid-upper 60s dews in early April is pretty decent if you ask me). It looks like there will be more to be had this next week, as the 7-day WPC rain forecast (see below) suggests over 2" may fall across much of OK and parts of TX as well. Even drier areas to the west look to get in on some of the action.
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CPC agrees and has wet anomaly probabilities for the southern/southwest US over the next two weeks:
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It's never fun to see an extended hiatus from severe weather after an active week early in the season, but hope is high that we have many good weeks of chaseable severe weather ahead of us this year. While the predicted 500 mb height anomalies from recent CFS runs are a little conflicting (both positive and negative anomalies west of the central US, see below), the forecast for below normal heights in the southern latitudes could be an indication of southern stream troughs coming through more often.

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Lastly, the CFS had a pretty good signal for this past week's severe weather when you look at the charts Greg Carbin has put together (http://wxvu.net/spc/cfs_scp/). Looks like it still only picks up a solid signal once something is in the 8-12 day range, so don't get too concerned about the lack of "hot" boxes showing up down the line. It may not mean anything.
 
So if the CFS continues to show jack squat for may 2-3, which is one of my only possible chase weekends on the plains this year, don't worry? You mean they can't predict weather that far out???? :)
 
This closed low spinning in the southwest seems to stall out later this week. With any moisture on the high plains, this could mean some severe weather. But you won't nail the forecast this far out. The NAM is all over the place with moisture and frontal placements. Definitely watching from Wednesday onwards.
 
This closed low spinning in the southwest seems to stall out later this week. With any moisture on the high plains, this could mean some severe weather. But you won't nail the forecast this far out. The NAM is all over the place with moisture and frontal placements. Definitely watching from Wednesday onwards.

Not thrilled about the winds aloft for the time frame, but Im sure that there will be some potential at some point, maybe trying to chase outflow interaction development one of the days and hope for the best?
 
Never thought I'd see a cutoff low setup in the Panhandle this early in the year. I expect this kind of stuff during September and October.
 
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