I’ll try and make this brief, since I need to do a forecast for today’s chase. We are in Dickinson, ND this Saturday morning. We left Gillette, WY yesterday afternoon and followed high based, non-severe storms from the Belle Fourche area north to near the North Dakota state border south of Dickinson. There just wasn’t enough moisture to sustain good, organized severe storms/supercells. It was pretty much a bust, for I thought we’d at least see a picturesque supercell. Oh well. My website is currently having some issues, and I’m lucky to get this blog update out, if I can. I’ll try and post pictures soon if the site can come back alive.
Today (Day 5), we are targetting an area between here and Bismarck it appears. The RUC breaks out storms in this area along a stationary front extending southwest to northeast across ND… from a deep surface low over Wyoming. Unclear what kind of storms we’ll be dealing with, but there’ll be higher CAPE today.
Here are some photos from yesterday’s chase:
Morning analysis shows a sfc low near Miles City with lower 50s dewpoints in northeastern MT. Looking at the 06z NAM, it appears this first sfc cyclone will continue moving northeast into western ND….with a weak front moving south into far southeastern MT by early afternoon. As this is happening, significant mid level flow perpendicular to the Big Horns will support pronounced lee cyclone development downwind of the Big Horns. The NAM has been showing this for many runs. Looks like that front will stall along a line roughly from Sheridan to Broadus to Capital. Winds east to northeast of this boundary will advect in near 50 dewpoints in this area it appears. 87/50F sfc parcel supports about 1300 to 1500 J/kg CAPE along this axis from Broadus to Capital by 00z. The shear profile looks very good with a broad looping hodograph in the 0-6km layer. This environment certainly supports supercells. Looks like we may head north to Broadus this afternoon.
Good morning from Gillette, Wyoming. This is as far northwest as any of us have overnighted on a chase trip. We left Scottsbluff, NE after lunch and visited Scottsbluf Nat’l Monument for a little sightseeing. The views from atop the bluffs are pretty amazing… what a great location to watch a supercell from! Here’s a group shot overlooking the city of Scottsbluff:
L to R: Matt Crowther, Stacie Hanes, Steve Wachholder, yours truly, Jay Antle, (Papa Cyclone) Jim Leonard
We then set off for the Devil’s Tower Nat’l Monument arriving there around and hour and a half or so before sunset. The drive up there was quite nice actually, it’s amazingly green out here in northeastern Wyoming. Some of the spring snows have really helped this area out. A marginal supercell thunderstorm developed northwest of Broadus, MT which was visible to our distant NNW from about 150 miles away. It was amazing I was able to hold a digital cell signal and download data at numerous points during the drive from Lusk to Sundance, WY. As we approached Devil’s Tower, that particular storm was weakening somewhat:
We spent a couple hours touring around and photographing Devil’s Tower. We were fortunate enough to have some cirrus clouds and good low sunlight to make the scenes more photogenic:
We arrived at our expensive Clarion Hotel (the only decent place we could find with available rooms given Memorial Day Weekend approaching and being on the interstate halfway between two of the most popular tourist destinations in the country — the Black Hills and Yellowstone.
Today (Day 4, Fri 5/26) looks like a chase day. We will be playing far southeastern Montana it looks like. I think a supercell storm can develop in the area northeast of Billings to Broadus… along the deep layer baroclinic zone. We should see CAPE values around 1000 to 1500 J/kg I think. The forcing will be better than yesterday, so I think there’ll be more storms. We already have reservations for Dickinson, ND in anticipation for what looks like a pretty good Day 5 (Sat 5/27). Jon, Rob, and Mitch will be driving up from Kansas City beginning tonight and will join us for Saturday’s chase. More later!
Well I’ll make a quick post here while I still have wireless data on I-80. We left Lincoln, NE after I picked up my new 18-55mm Nikon lens at the Rockbrook Camera store — which is a pretty darn nice store, might I add. Anyway, that lens and a UV filter set me back about 200 bucks. We are with Matt Crowther, Jim Leonard, and Jim’s friend Steve now heading west to the Nebraska Panhandle. It’s 4:30pm now near North Platte with a nice connection on my Alltel card. I’m very very pleased with the performance of the Alltel/Kyocera setup… I didn’t expect to have a near-continuous signal and download during the chase yesterday. It was very nice! We didn’t miss a single volume scan after we got into Nebraska which was great.
Anyway, a perusal of the models this afternoon (Jay’s driving so I got to do some model crunching 
), suggest that Friday there could be two plays… one being in the Neb Panhandle as low level moisture advects northwest into the region…and another play could be along the central ND/SD border. There are some moisture concerns up this far north, though, which we will have to consider. The best mid-upper flow will be up here though. Saturday…. man… the "fantasy" 84-hr Eta shows a LOT of low level moisture with a nice surface pattern over North Dakota. Good west southwesterly flow in this area as well with a halfway decent 700mb baroclinic zone. There’ll be capping concerns, for sure, but this is where the best shear will be in the whole plains. Interesting that the GFS is suggesting some moderate 850-500mb flow coming into the Central High Plains and even the TX Panhandle Saturday… but the upper tropospheric flow really stinks in between the main polar jet and the subtropical jet wayyyy to the south.
Anyway, I think the plan is tomorrow will be a leisure day… and we will have several more model runs to pin down Friday and Saturday. They both look like legit chase days to me with organized severe storms.
Jay, Stacie, and I targetted the area around Phillipsburg by mid-late afternoon where surface convergence appeared to be maximized. We tried to stay as far south as we could as it appeared most of Nebraska would erupt in too many storms. It turns out that indeed happened. The problem was, storms in our target area were developing out ahead of the boundary layer convergence or the remnant Pacific cold front itself. We monitored trends in radar and the sky, and it just wasn’t clear which storm was the best to intercept. Finally, around the town of Guide Rock, we stopped to let the atmosphere hopefully straighten itself out in hopes that a coherent severe storm could evolve.
We watched a small storm approach us from the southwest near Guide Rock both visually and on radar, which had up to 65 VIL at times. As the storm got closer, we could hear a faint hail roar. We continued east about 5 to 7 more miles to stay ahead of this marginally severe storm. We stopped a couple times east of Guide Rock to photograph the structure of the updraft of this storm, which was somewhat respectable. It appeared marginally supercellular-ish when it was between Guide Rock and Nelson…to the southeast of the main developing SVR line forming on the cold front. We went north on Hwy 14 and our storm became worse looking visually. We met up with Matt Crowther and Jim Leonard north of Nelson and continued east on Hwy 4.
The rest of the chase just sucked.. at least for me. Storms on the cold front began to get much better organized to our west-northwest. We decided to hang out for awhile at this location on Hwy 4 somewhere not too far west of Davenport. The light was getting low, so I decided to set the tripod up for photography. Inflow winds were gusting to about 30-40mph from the southeast… which was promising! I left my tripiod un-attended for about 20 to 30 seconds or so out of reach. You can guess what happened next. I don’t have my heavy duty Manfrotto tripod with me, but more of a lighter-weight landscape photographer’s tripod legs. Anyway, the tripod fell forward, lens-first onto the gravel road. I completely busted my 18-70mm lens. The body is okay, though thankfully. So that was about a $300 lapse in judgement not paying attention with very strong winds. It’s a good thing we are in a fairly decent sized city (and I have some supplemental cash) so I can replace this lens right away. I missed out on some decent low light structure shots as we were driving north on Hwy 81 in Southern Fillmore County…. oh well. It’s only Day 1….
Today: We had talked about chasing southeast KS last night… or at least considered the option… it’s not even 8am yet as of this time. We may blow off today, like we had originally thought and head west (after I buy my new lens) towards western Nebraska. The NAM and GFS are now throwing a bit of a curve ball at us with regards to Friday and Saturday… it’s showing more of a "dirty ridge" scenario now across the central High Plains… where enough flow could cut underneath into western KS to make things just interesting enough. Both the NAM and GFS develop storms just north of the thermal low somewhere in Northern KS on Friday. I think by heading into western Nebraska… like Scottsbluff or something… we can keep this option open… because it still isn’t exactly clear.
Target: Mankato, KS by ~4pm
Good morning! Didn’t get a whole heck of a lotta sleep last night… getting everything ready to set out for the chase. Stacie got here about 12:30am, and in a couple hours Jay will be arriving. It appears everything is on track for a decent supercell setup in north-central Kansas. The target appears to be along the Hwy 36 corridor between Smith Center and Belleville. WSW flow at 500mb of 40-50 kts will spread over the remnant Pacific cold front "acting dryline" promoting very healthy deep layer shear. Low level moisture will be marginal at best for tornadoes, but given the shear environment, it is certainly possible to get a tornado especially between 7 and 9pm when the 0-1km shear ramps up significantly.
As it stands now, after today’s chase… we are looking at two down days. Wednesday we will likely drive to Rapid City and Thursday will be a leisure day around the Black Hills. Low level moisture will likely increase enough for decent storms on Friday. One hell of a cap will be in place south of the Dakotas with widespread near-100°F heat expected from western Nebraska into the TX-OK Panhandles. In this situation, it’s best to be near the 700mb baroclinic zone… which will be well into the Dakotas Friday and even into the weekend.
It’s Monday morning, the day before Day 1. I met up with Matt Crowther and Jim Leonard last night here in Dodge as they set out for their trip. It looks like they’ll head into Colorado today to try and catch anything off the Palmer Divide towards early evening when some of the good upper flow comes out. Last night was rather interesting. We ate at Montana Mikes and we all got a free dinner thanks to a car accident near 14th and Wiatt Earp. One (or more?) of the involved parties ran into a power pole and took out the power along West Wiatt Earp, so the power went out for a good half hour to 45 minutes before our food came out. Fortunately, we timed it just about perfectly as they must have just finished cooking our food before the power went out. The salmon was still good, even though we all ate our supper in the dark… well not pitch black, but you get the idea. We then headed to my work (NWS-DDC) to look at some new 00z model stuff.
Jay, Stacie, and I will probably reunite with Jim, Matt, and Jim’s friend from Florida (they are all chasing in Jim’s van) on Tuesday. Below is my last installment of the “dart-board”. The last dot is now in north-central KS. I think there may be a decent “tail-end Charlie” play in this area Tuesday. Jay will be driving down from Lawrence very early Tuesday morning and will leave his car here in Dodge for the two weeks we are out. Stacie will be arriving late this evening.
Looks like after Tuesday, we’ll be down Wednesday and Thursday (not chasing), but setting up in the Dakotas (likely Rapid City) for late-week/early weekend activity. The 850-700mb baroclinic zone will be up here, along with the best mid-upper winds, so this is where we’ll be. There are growing signals that towards late weekend into early next week…. once Jon, Rob, and Mitch come out (They’ll be joining us on Saturday), we’ll begin to shift our focus south I think… the ECMWF shows some decent 500-200mb flow shifting into the southwest as another deep trough (hopefully) evolves eastward into the intermountain west. This would probably result in increased southwesterly flow all across the High Plains. Early next week (like around the 30-31??) could be interesting — a wide open Gulf with very good looking trajectories originating from the deep tropics…allowing for very good moisture. We’ll see. The 29-31 of May is a historic hot time anyway, so there’s hope there.
- Day 1, Tue 5/23=N. Central KS (photogenic supercells?)
- Day 2, Wed 5/24=Travel to Rapid City (down day it appears)
- Day 3, Thu 5/25=Sightseeing? (looks like a down day, not much moisture yet?)
- Day 4, Fri 5/26=Southern Dakotas (looks better for chasing)
- Day 5-7, Sat 5/27 to Mon 5/29=Trending a bit farther southwest each day into the central High Plains as new trough emerges in the west??? Very preliminary. Climo would support this).
Well… all along it certainly appeared that there would be a significant chunk of that big Pacific trough would eject northeast into the Plains. The question was when it would eject…and exactly where and how strong. It appears we finally have enough consensus in the models to say that the “when” will be Tuesday (the 23rd) and the “where” will be somewhere in Nebraska.
Given this faster scenario…and the fact that Wednesday (our original start day) looks marginal at best in western Iowa along with Thursday being down, it appears… I decided to take Tuesday off work and have Stacie and Jay meet me here in Dodge earlier so we can make Tuesday a chase day.
Anyway, the updated dartboard is below.. I changed the Day 1 to May 23 and the icon on the dartboard for May 23 is a blue circle instead of a star to represent this change in Day 1.
The scenario I’m playing in my head now is..
- Day 1, Tue May 23=Nebraska (photogenic supercells?)
- Day 2, Wed May 24=Western Iowa (early afternoon under cold pool aloft?)
- Day 3, Thu May 25=Travel to Dakotas (down day?)
- Day 4, Fri May 26=Somewhere in the Dakotas (marginal supercell chase day?)
- Day 5 and beyond…. ?? (Wayyy too unclear)
The 24th may very well be a “Day 2 Setup” day. It’s still 5 days out, but the new GFS including Ensembles, Canadian, and ECMWF model suggest that the lead system of interest will rapidly eject northeast into the Rockies and substantially weaken as it hits the ridge. This would put the central plains in a weak-modest short-wave northwest flow behind the system with a front well to the south. Should this pan out, then there won’t be any chasing Wednesday. I don’t want to chase south on Wednesday, because it would just be a one-day deal…. then a haul clear up north where the Day 6-8 progs are showing very nice flow coming across the northern Rockies into the northern High Plains. It will take awhile before adequate moisture makes it up into northern Nebraska/Dakotas… but this is clearly where the best mid-upper flow will be for supercells. So, at this point, from what I see in today’s GFS… The “dart” will be Rapid City… and the Firehouse Brewery 
…a logistical target only for Thurs-Fri setup. Subject to change of course……. stay tuned!
GFS 500mb:
GFS Surface:
Canadian Model:
Here’s the updated dart-board. The red star means it’s a Day-2 positioning destination, and not really a chase-day target based on the GFS. More later!
Well the 00z and 12z runs of the GFS today show a similar pattern, which offers a little hope in terms of maybe some consistency beginning to show up for the 24th… that is until you look at the 18z run. The “off hour” runs of the NCEP models are usually quite suspect since they do not have the benefit of RAOB data (which are 12z and 00z). Anyway, both the 00z and 12z runs today (the 18th) show a nice shortwave trough over the northern Rockies entering the northern High Plains with a discrepency in timing.
GFS 500mb:
GFS Surface:
Here is today’s 12z GFS Ensemble graphic of 500mb heights and precipitation… Great uncertainty exists over the northern plains and midwest where it looks more like spaghetti. In looking at the 0.50″ QPF contour, it looks like there’s a storm track across the northern plains and midwest. There’s a huge timing issue… but keep in mind, this is still a day 6.5 forecast!!:
The 12z Canadian global model (not shown) also supports a storm system over the northern Rockies ejecting from the large Pacific trough. The problem is, it is about a day faster than the GFS…. which, if more correct, Wednesday the 24th could either be a) a down day, or b) much farther south along the front in the Central Plains.
The upshot is… who knows! That’s the key… it’s 6 days out, and the models continue to be all over the place… but this is expected…. we won’t be able to get reliable signals for a chase target “region” (or if we’ll be chasing at all the first day) until about 108 to 120 hours… if we are lucky… and more realistically 72 hours. But, to continue the game, the “GFS Deterministic dart” for today will be in the same general area as before:
