Back to regular life and setups

So wouldn't you know it, there's a setup on the way that looks really good. I'm talking spectacular. Let's talk about it.

Moisture is at its peak right now. Surface dews are progged to be in the low 20s. Up to 850, even, it looks to be moist--dews over 15°C.





That will lead to slightly-capped MLCAPEs in excess of 1000 and even 1500 J/kg. Not too shabby, if you ask me.





With 500 mb flow increasing with the approach of a vigorous trough, deep-layer shear will be good--great, if you add in the 850 mb winds crossing rather nicely (shown above).



Surface lifting will, I suppose, be a question but if a front or outflow boundary sharpens up, the game will be on.

If I were chasing, I would aim for Weyburn, SK, for an initial target and go from there.

U of M chase trip is leaving tomorrow

We're off tomorrow morning, pretty early.

I will be posting the bulk of my updates on the other blog--http://wxcentral.blogspot.com/--so check it out if you like.

I'm excited, like a kid on Christmas Eve. Or me on Christmas Eve, truth be told.

U of M trip forecast: better late than never

So here’s what it’s looking like now. I will post my ideal locations as though we had a teleportation machine. Since Thursday is the theoretical earliest we can start chasing, I will start from then and go as far into the future as Canada Day. I will give each day and run a completely arbitrary rating on a scale of 0 to 10, 0 being horrible and 10 being the best setup ever. Keep in mind this is model land and I’m basing my judgments on believing as though the depicted scenario were exactly what was going to happen.

NAM (12Z):
Thursday – northern Montana and/or adjacent areas of AB/SK (4 – instability is kind of weak and winds are a little far back)
Friday – northeast Colorado/Nebraska panhandle (6 – instability and deep shear are good but the directional turning is only okay)

GFS (12Z):
Thursday – central Alberta (5 – instability is weak but the winds are more favourable)
Friday – northwest Nebraska/southwest South Dakota (6 – instability and deep shear are pretty good but the directional turning is lacking)
Saturday – northeast Colorado/Nebraska panhandle (6 – instability and deep shear are pretty good but the directional turning is lacking; do we sense a theme here?)
Sunday – a few areas, including western Kansas (5 for okay deep and directional shear with good instability), the Nebraska panhandle (7 with good potential juxtaposition of parameters but it may be only okay) or northern South Dakota (6 with slightly weaker winds)
Monday – southeast Alberta (6, as wind fields are better but moisture is lacking) or northern South Dakota (6 for good instability but weaker deep wind shear, although nice turning)
Tuesday – western North Dakota (8, as wind fields, both deep and directional, and instability look better)
Wednesday – western Manitoba or southwest South Dakota (9 – instability and shear look really good)
Thursday – northwest South Dakota (4 mainly for capping)
Friday – western North Dakota (8 if the cap breaks)

ECMWF (00Z) (I can’t do forecast soundings, though, so I have to guess the ratings a bit more):
Thursday – eastern Alberta (6 depending on moisture)
Friday – eastern Montana, I think (5, based on it’s unclear but looks like there’s some potential)
Saturday – southern Saskatchewan (6)
Sunday – eastern Dakotas (7)
Monday – western Kansas but probably too capped (4)

GEM-Global (12Z and 00Z):
Thursday – northern Montana or southeast Alberta (5)
Friday – southeast Saskatchewan (6) or western Kansas if it’s not capped (6)
Saturday – central South Dakota (7)
Sunday – north-central Nebraska, specifically Cherry freaking county (7)
**now changing to 00Z run**
Monday – maybe the Colorado front range, but that looks marginal (2)
Tuesday – eastern Alberta (6)
Wednesday – eastern Dakotas or the Red River Valley (7)
Thursday – southeast Alberta (8)

NAEFS (00Z):
Thursday – southeast Alberta (5)
Friday – Nebraska panhandle (6)
Saturday – western Nebraska (6)
Sunday – western North Dakota (7)
Monday – western North Dakota (6)


Wow, that was exhausting. The models are seeming to key in on a potential play on Thursday in Alberta, but then they almost all unanimously drop the potential into the states, and well into them at that. Nebraska panhandle for a couple of days, or maybe into the Dakotas. It seems that the usual suspects, moisture and midlevel winds, are the main players here. Moisture is there south but the winds aren’t. And it seems the good midlevel flow dies as soon as it hits North America. Weird.

(cross-posted at the Weather Central blog)

CoD trip pictures

Here some of them are. In these pics you'll see structure, a tornado, and some lightning shots. Enjoy!

CoD chase, day 9 recap

We started off the morning in Garden City, KS, full of hope. We went east for some yummy BBQ in Wichita. Then we dropped south, as satellite and RADAR indicated convergence near the Oklahoma border. We went hither and yon for a while, waiting for initiation, as the cumuli were becoming rather congested and MLCAPEs to our immediate southeast, the airmass source region, were approaching 5000 J/kg. Sweet.

Storms finally fired up and we were on the south one in a jiffy, and as soon as we got to the south of it, it showed us a beautiful structure, with striations and nice midlevel rotation. We followed it for a few hours, and a couple of times we witnessed clear slot occlusions; still no tornado.

The road options were getting a little sketchy, so we had to drop southeast by about 15 miles. And wouldn’t you know it, when we’re coming back north, that’s when the storm decides to tornado. We saw it and dropped a report on Spotter Network. We couldn’t find an appropriate place to pull over for pictures for a while, so we had to settle for van pictures.

Not bad, though, as the tornado was on the ground for an estimated 15 minutes. After the old circulation got gobbled up, the new circulation tried hard but could never regain its strength again. So we went to grab food and unload water, and set out north for some lightning pictures. Some pictures acquired were amazing. After about a half hour of that, we left for the hotel in Springfield, MO.

Pictures will on their way tomorrow.

CoD chase, day 8 recap and day 9 forecast

We started the morning knowing things would get going early in Colorado. It's a lot like Alberta in that the storms form because of the mountain-plains circulation. If there's cold air aloft and some flow, storms go early and they can go big. We were dealing with low dewpoints, however, and so we were expecting wind and hail makers.

And that's just what we got. We got a bunch of really neat structure while staying on storms for hours and hours. We were in cold air and warm, moist-ish air and dry. I took more pictures yesterday than I have in all my other chase days this year combined. On the way back to the hotel we took some lightning pictures, although most were marginal. The lightning we watched later in the van was amazing, mostly sheet, and constant. Coupled with blasting music by Rush, and it was a great day.

Today we're looking to southeast Kansas. Moisture--surface dewpoints are already in the low 70s F. Instability will be there because of the moisture, and we're looking at MLCAPEs of 3500+ J/kg. Uncapped. Lift should be good along a composite warm front/outflow boundary, enough to overcome the only modest cap characterized by 700 mb temperatures of 10C. Shear will be good. 35 knots at 500 mb from the west and easterly surface winds of 10 to 15 knots will make storms easily rotate. We'll even be in the left exit region of an 80 knot 250 mb jet.

Now the minuses will be the moisture at 850 and winds at 700. The surface moisture will be good, so that should overcome the lack higher up. As for the 700 winds, I don't know what to say or what effect it will have on storms--strictly speaking, though, the hodographs won't be too bad, especially in southeast Kansas.

I expect we'll be looking at wet classic supercells today, given the moisture. Who knows what kind of surprises we may see. It should be fun. (Especially after stopping at Hog Wild). (Maybe.)

CoD chase, day 7 recap and day 8 forecast

Yesterday was a neat day. We were expecting some supercells with a chance of tornadoes, but something just didn't go. Likely the moisture was to blame, but this year it seems to be either too much or not enough, or too much forcing or not enough--that delicate balance doesn't seem to want to show up.

Still, though, we caught some great shelf cloud structure. Pictures may or may not happen soon, depending on when we end up leaving on our trip. Speaking of which,I normally do extended forecasts for the trip based on the models and show how wildly they vary from day to day, but I have no time right now.

Today we're going to play the Palmer Divide east of Denver. Maybe, maybe not; this place is famous for its landspout tornadoes, and you never know.