Glendive, MT

We're still trying to figure it out. A hope is the line of cumuli so our south and a wave approaching the line from the west. The road network sucks around here, though.

There's also some development to the north. We're going to wait for more data and see if we can glean some more information and make a decision.

One more note--breakfast

Biscuits and gravy? Worst. Hotel. Breakfast. Food. Ever.

Day 1: busted in ND

So we kept going west until we were almost out of west. Okay, not quite, but we got to our initial target area late in the afternoon and lo and behold, there was an agitated field of cumulus to our west. Convergence and instability were very good in that area, and so we were happy.

Then we looked at the RADAR. A monster supercell had formed where we had discounted the chances--far southern Saskatchewan. This storm was beautiful on RADAR--it had intense rotation, a good kidney bean shape, it had it all. And it was the only storm in town.

So of course we decided to go after it. We got out of the badlands west of Dickinson, ND to see the storm--it was 200 km away, but we could see it. Hard towers going up along an extension of the same moisture boundary that we were chasing--there was just much less instability there. So why was it going?

I think it was more jet-induced--way more lift there to help out the pitiful instability.

Anyhow, when we got within about 100 km of it, its look changed dramatically. Instead of hard towers flying up into it, the storm started to look all fuzzy. Not good. Mobile ThreatNet confirmed what we were seeing--after about 4 hours of life, the storm was dying.

So we stopped in a scenic spot to take some pictures and then bailed for the evening.

What caused the storm to die? I like Wxdog's hypothesis--that the storm had moved so hard right (south, pretty much, instead of southeast--that while ingesting the better moisture, it also had a chance for the dry west winds to its west to catch up to it, polluting the updraft. Whatever the cause, it just decided to stop doing its thing. (And no, back in our initial target area, nothing went.)

So here we are in Dickinson, ND, getting ready to go to the Black Hills. Today looks pretty good, as does tomorrow in Nebraska. SPC seems to agree with us, and today will have what yesterday was lacking--Black Hills magic.

Also, today will have much less driving. Good deal.

Fargo

Quick lunch stop and then heading west toward Bismarck. RUC soundings and even WRF show good CAPE and moderate shear. I suspect we may see some high-based supercells today. Time to go.

Now that the contest is out of the way

My contribution to the contest (were I able to win) would be Mott, ND.
That being said, each of the entries has validity. And who knows who will win?

It looks like things will get better from day to day during the chase. Moisture will increase, flow will sharpen up, and we should be able to be in position. Touch wood, I think our prospects for a) chaseable storms and b) picturesque storms are very good indeed.

Now I really need to get to bed because we leave in less than 8 hours.

Contest submission closed

Ah, so you were waiting till the last minute.
I have 8 entries submitted--7 official and one unofficial. The locations surprised me, but each has its merits.

They are:
Abilene, TX (2)
Lisbon, ND
North Platte, NE (2)
Le Mars, IA
Minneapolis, MN
Miles City, MT

Good luck to all!

Contest update

That's better. As of 11:23 PM I have 4 entries--3 students, 1 not.

Contest? What contest?

As of 10:51 PM (68 minutes before the contest closes) I have received a total of one entry. And that's not even from an eligible student.

We're going!

After much discussion, we have decided to leave on our chase in the morning.

Things are starting to come together for about 5 days of okay-to-good chasing stateside. Moisture has been swept away by a cold front, but it shall gradually return, so that by next weekend the dewpoints will once again approach 20. The thing is, the farther west you go, the lower the dewpoints need to be to cause great storms.

As always, I'm excited and nervous about what the week will bring; no doubt, though, it will be unforgettable.

Note about this blog: once we're on the road, I will likely update more than once a day, pretty much whenever I can. I'll try to include our location, our proposed destination and any interesting stories that may come up. Also I'll discuss model output and differences, and the implications on what we may see.

CONTEST and Saturday evening musings

First off, the musings: so today was my last day at work for about a month. And it ended with a bang!

At just after 8 PM, Doppler RADAR was really showing something bad, and I had to issue a tornado warning for areas near Winkler and Gretna. We didn't get any reports, but it wouldn't surprise me to hear about a spin-up in the region.

Now onto the contest:

We are offering a small prize to students in this year's class for winning the contest. It's pretty simple, really. (And I wasn't given much in the way of direction for it, so I'll make up the rules and terms of the contest.)

Give us a target for the first day of the chase. For the sake of the contest, let's say the "first day" is Monday, June 29. I want the name of a town and its state or province. Email your entry by 11:59 PM Sunday June 28 to me (you have my email address). The winner will be the person with the most severe weather reports within 100 km (or suitable radius decided by the judges) of the target area; the severe weather reports include wind, hail and tornado; tornado reports will garner 2x the points of the other kinds of severe weather.

Like I said, the prize is a small prize, but the idea is more to flex your forecasting muscle. Let's see your best!

00/25Z run: last forecast by me, and then it's your turn

Before I go into this forecast, let me say that it's still uncertain as to where we'll be going; it doesn't seem uncertain, though, that we will see storms, and likely good ones, too.
The GFS is pretty much the only one from which I've been able to get any indication about instability; let me say, too, that the instability progs have been all over the map (literally). So for instance, day 1 looks like a split between dynamics (Kindersley, SK) and thermodynamics (Alliance, NE). Where will it be? Only time will tell. I have a hunch, though, that we may need our passports.

And now, the last forecasts I'll be posting on here until the trip starts.

Day 1 (June 28)
GFS: Kindersley, SK (D) or Alliance, NE (T)
GEM: Wynyard, SK
ECMWF: Coronation, AB
NOGAPS: Kindersley, SK

Day 2 (June 29)
GFS: Swift Current, SK (D) or Rapid City, SD (T)
GEM: Dauphin, MB or Rapid City, SD
ECMWF: Moose Jaw, SK
NOGAPS: Estevan, SK

Day 3 (June 30)
GFS: Pierre, SD
GEM: Red Deer, AB
ECMWF: Estevan, SK
NOGAPS: Bismarck, ND

Day 4 (July 1)
GFS: Omaha, NE
GEM: Kindersley, SK
ECMWF: Lethbridge, AB
NOGAPS: Fargo, ND (?)

Day 5 (July 2)
GFS: Rapid City, SD
GEM: Assiniboia, SK

Seriously. All. Over. The. Place.

24/00Z run

For the last 2 days of the forecast, I'll be adding in other models as they become available. Today I add the NOGAPS.

Day 1 (June 28)
GFS: Red Deer, AB
GEM: Medicine Hat, AB
ECMWF: Coronation, AB
NOGAPS: Lloydminster, AB

Day 2 (June 29)
GFS: Nowhere
GEM: Medicine Hat, AB
ECMWF: Medicine Hat, AB
NOGAPS: Williston, ND

Day 3 (June 30)
GFS: Medicine Hat, AB
GEM: Melita, MB
ECMWF: Swift Current, SK
NOGAPS: Williston, ND

Day 4 (July 1)
GFS: Esther, AB
GEM: Nowhere
ECMWF: Yorkton, SK

Day 5 (July 2)
GFS: Lethbridge, AB
GEM: Williston, ND
ECMWF: Nowhere

On a side note, Friday looks pretty good around here. I'll be working but I'm sure some of the former students will be out, lurking for storms.

June 22, 2009 chase: southern ND

Our initial target was west of Fargo, ND. All the ingredients were there for supercells, but the 850 mb winds were on the weak side; this told us that tornadoes were a lot less likely.

We got to Fargo and storms were going on a couple of hours west, and there was also a line of agitated cumuli around Jamestown. The towers were trying to go up near JMS, but it seems they were struggling with the shear. They leaned over in a big way. So we decided to target some of the storms to our west, all while keeping an eye behind us in case storms should go up there in the better moisture.

Well, the towers near JMS never did anything, but the storms west did. There was a north to south scattered line of discrete supercells going on, and it was just a matter of picking the right one. The one we initially targeted got choked off by one attacking it from the southwest, but there was one farther south along the line that was moving well to the right of the motion of the others. (Baron Mobile ThreatNet, while not very high resolution, helped us tremendously in this regard.) We got to a good vantage position on it and observed a good hard set of towers going up on it, with some ragged organization at the updraft base.



The storm was clearly having troubles keeping the outflow from cutting off the inflow, but for a while it seemed to strike that delicate balance where the rain-moistened air was being re-ingested into the storm and causing more structural beauty. It was looking like an almost small HP supercell at this point; we were not surprised at this point to hear a tornado warning for the storm. This was the most organized it got.



Soon after, the outflow won. It showed us a nice outflow tail attached to the storm.



And soon after that, it was gone.

All in all, a great day with beautiful structure.

23/00Z run

It's way later (over 12 hours) than when I've been posting it, but I was chasing and got in late last night (early this morning, and pictures to follow in a blog post) and I haven't gotten around to it till now.

By the way, the last of these forecasts as such will be Thursday; as we get closer to the date (namely Friday and Saturday) we're going to ask the students to submit their forecasts based on the available information.

Day 1 (June 28)
GFS: Bowman, ND (heehee)
GEM: Swift Current, SK
ECMWF: Lethbridge, AB

Day 2 (June 29)
GFS: Fort Morgan, CO (wow)
GEM: Swift Current, SK
ECMWF: Lethbridge, AB

Day 3 (June 30)
GFS: Fort Morgan, CO
GEM: Lethbridge, AB
ECMWF: Lethbridge, AB

Day 4 (July 1)
GFS: Casper, WY
GEM: Swift Current, SK
ECMWF: Coronation, AB

Day 5 (July 2)
GFS: Alliance, NE
GEM: Not really anywhere
ECMWF: Pincher Creek, AB

Wow, it's a good thing that forecast models have no shame; otherwise, they'd be so embarrassed about a) their flip-flopping and b) their lack of inter-model agreement. Even 5 days out the agreement is truly awful. What this tells me, then, is that there are things out in the Pacific that the models have a poor handle on. But what heartens me (touch wood) is that none of the models is painting a death ridge anywhere.

22/00Z run

Note: I will post the ECMWF-derived forecasts in the morning, as I have to get up at a reasonable hour and can't afford to wait for it.

Day 1 (June 28)
GFS: Minot, ND
GEM: Kindersley, SK
ECMWF: Medicine Hat, AB

Day 2 (June 29)
GFS: Dickinson, ND
GEM: Calgary, AB
ECMWF: Swift Current, SK

Day 3 (June 30)
GFS: Bismarck, ND
GEM: Red Deer, AB
ECMWF: Nowhere

Day 4 (July 1)
GFS: Nowhere
GEM: Saskatoon, SK
ECMWF: Resetting for the next day, likely in Alberta

Day 5 (July 2)
GFS: Nowhere?

This looks a little weird, the GFS. It's moving the trough through the flow rather quickly; troughs actually tend to stick around for a lot longer than the models depict. As well, the forecast here, if it comes true, is for severe thunderstorms of the rotating variety. Every day seems to have some pretty wicked CAPE--it's just a matter of whether it's collocated with the midlevel flow.

21/00Z run

Edit: Wxdog informed me that the ECMWF run is available to us for this forecast; I will include it from here on in, and amend this run's forecast to include it.

Wxdog sent me this panel from the 20/12Z run of the GFS, and entitled the email "You know you're chasing with the U of M when..."

The panel shows the forecast CAPE for our first day out chasing. I will still remind everyone, of course, that the model will flip-flop lots of times before it reaches anything close to reality.



Now, onto the forecast.

Day 1 (June 28)
GFS: Lloydminster, AB
GEM: Nowhere (death ridge)
ECMWF: North Battleford, SK

Day 2 (June 29)
GFS: Moose Jaw, SK
GEM: Nowhere (death ridge)

ECMWF: Broadview, SK
Day 3 (June 30)
GFS: Baker, MT
GEM: Nowhere (death ridge)
ECMWF: Nowhere (atmosphere reloading, appears to be getting ready for another Alberta day)

Day 4 (July 1)
GFS: Grand Forks, ND

Day 5 (July 2)
GFS: Nowhere

20/00Z run

Day 1 (June 28)
GFS: Coronation, AB
GEM: Red Deer, AB

Day 2 (June 29)
GFS: Coronation, AB
GEM: Coronation, AB

Day 3 (June 30)
GFS: Brandon, MB

Day 4 (July 1)
GFS: Dickinson, ND

Day 5 (July 2)
GFS: Calgary, AB

This is really changing like crazy! For example, the day 1 GFS solution has had as a "target" Calgary (twice), Saskatoon (twice), Banff and Coronation.

Wanna really see how much model forecasts change, especially in the long range? Check out this 250 mb panel comparison (from CoD); both panels are valid for the same time (29/00Z) but are from runs 12 hours apart. Note the location and orientation of the jet stream west of Vancouver Island in each panel. 'Nuff said.




On a side note, it looks like I will be going out for a chase with JH on Monday and Tuesday. Here's what Monday's forecast sounding looks like (courtesy wxcaster.com).

19/00Z run

Day 1 (June 28)
GFS: Banff, AB (marginal)
GEM: Rocky Mountain House, AB

Day 2 (June 29)
GFS: Lloydminster, AB

Day 3 (June 30)
GFS: Lloydminster, AB

Day 4 (July 1)
GFS: Estevan, SK

Day 5 (July 2)
GFS: Regina, SK

Keep in mind these targets will likely change every day. Our first day could end up being in Nebraska, for all I know.

18/00Z run

Here I go:

Day 1 (June 28)
GFS: Calgary, AB (marginal)

Day 2 (June 29)
GFS: Edmonton, AB

Day 3 (June 30)
GFS: Estevan, SK

Day 4 (July 1)
GFS: Melita, MB

Day 5 (July 2)
GFS: Pierre, SD

Wow, what a change!

Third day of forecasts, and the final day added to the forecast period

Here's the outlook for the 17/00Z runs, and it shocks me that the first 3 days have similar forecasts to yesterday's run:

Day 1 (June 28)
GFS: Saskatoon, SK

Day 2 (June 29)
GFS: Winnipeg (marginal) but nowhere, really

Day 3 (June 30)
GFS: Jordan, MT

Day 4 (July 1)
GFS: Winnipeg, MB

Day 5 (July 2)
GFS: Fargo, ND

I find it interesting that the model didn't change much in the super long range, in terms of locations, for the first 3 days of the forecast. That isn't to say, however, that it's got the same kind of setup for each day forecast; it doesn't.

Wow, this post was late. There was a likely severe thunderstorm west of The Battlefords, SK with large hail. I say likely because as of this writing, no reports of large hail have been received. It's also interesting that this storm has almost no deep shear to work with. It fired on the northeast end of a pretty strong vorticity centre, though, so maybe it ingested some of that vorticity and that's what made it last so long (and likely rotate).

Second day of forecasts, another day added to the forecast period

Here's the outlook for the 16/00Z runs:

Day 1 (June 28)
GFS: Saskatoon, SK

Day 2 (June 29)
GFS: Winnipeg (marginal) but nowhere, really

Day 3 (June 30)
GFS: Jordan, MT

Day 4 (July 1)
GFS: Havre, MT

Already there have been some wild swings. Expect that to happen pretty much with every run and really, the locations won't likely sharpen up and remain consistent until we're about 5 days out, and really we should have a good idea of the approximate target for the first day by June 26.

Storm chase trip 2009: anticipation

This year, in addition to all the funky gadgets we already have, we will have a new toy (okay, tool) to play with on the trip: Mobile Threat Net. It's essentially near real-time RADAR (both Canadian and American) delivered by XM satellite radio. Justin Hobson (the technology guy on this year's trip and possibly more of a weather geek than I am) and I took it out for a test run a couple of weeks ago and, while not perfect in what it delivers, what it does provide was given admirably.

We also have (from past years) an airmar, GMRS radios, door magnets for the vehicles, and some other neat stuff.

Personally this trip will mean a lot to me because I haven't seen a tornado since Elie and Oakville of 2007 (yes, at the same time) but also because I had 10 days to chase at the end of this past May and it turned out to be one of the convectively quietest Mays in North America since severe weather records have been taken.

My statement above shouldn't mislead you, though: I have realized over the past couple of years that my main goal in storm chasing is to see and document the structure of thunderstorms. I love seeing the striations in a storm indicating the organization in it; I love seeing tilted, hard towers rocketing up into the sky. That's not to say, however, that my ultimate goal isn't to see a tornado--it is, but it's more like icing on the cake. Sweet, sweet icing.

Now onto what I'll likely be blogging about for most of the next 2 weeks, hopefully every day: what the models are saying and how this year might play out. The "targets" should change with each successive run. I will start off with the disclaimer that what I will provide is more or less the subjective assessment by one meteorologist (me) of what the various models, as they become available for such assessment, are saying. I will not attempt to analyze how the models have been initialized or how they've been performing lately. I will also not try to include logistics/feasibility of getting to a target on any day. In the long range, using the models at all is a fool's game; consider me, therefore, a fool.

Numerous things can royally mess up how models fare in their solutions, including convection occurring at initialization time (very common) and tropical systems (none so far and, touch wood, we won't have any this year). And that's only naming two things.

As we all know, we've had to wait for warm weather to arrive, and that has affected how the severe weather season has been going; in a nutshell, the severe weather season has been delayed by about 3 weeks, so when we set out there's a good possibility we could be going out in the peak season for areas like Nebraska and South Dakota. Of course, every year is different so my previous sentence may mean exactly zero.

All that said, here's the outlook for the 15/00Z runs:

Day 1 (June 28)
GFS: Calgary to Edson, AB

Day 2 (June 29)
GFS: Regina, SK

Day 3 (June 30)
GFS: Regina, SK (again)

And that's as far as any of the models that are accessible to me go out; more will be added as they become available.

I hope you join me on this journey into the folly of models and wishcasting, as well as follow us on the trip (if you won't actually be in the vehicles with us).

Derecho in progress

A derecho is currently going through the Unites States. It started this morning in northern Oklahoma and, as I write this, is going through northern Mississippi and western Tennessee.

The SPC issued a PDS severe thunderstorm watch (link will be invalid after 2009) for this--a rather rare event. In the wording of the watch they mention winds to 105 mph.

If you go to the SPC severe weather reports page for today, you can clearly see the swath of severe weather caused by this derecho.

Here's a current base reflectivity image of the derecho (courtesy CoD).


And the associated base velocity image.



This storm will, I'm sure, be the subject of many studies in the future.

June 6, 2009

A former student of the storm chase course, Justin Hobson, is in Nebraska City, NE right now waiting for initiation. Things look pretty good out that way--and had I not had prior commitments that I couldn't get out of, I would have been there with him.

I'm glad to see former students (and future meteorologists) taking such an interest in our own "sport". It makes me think that a) we're doing something right and b) there's hope out there.

22 days until we start the trip this year. I can hardly wait. The group is a good one, and I think we'll all enjoy one another's company.