June 10, 2011 Chase Update

I have about a dozen days to catch up on.  I am currently enroute from Cameron, MO, to SE KS.  Let’s see if I can wrap up the previous 12 days here…

May 30—this was the second full chase day for Tour 4, and with drivers Danny and Chad.  We left West Point, NE, and targeted the middle of NE, near Albion.  Some severe storms went up quickly southeast of Brewster and raced northeastward through a sparse road network.  This was no fun at all.  At the end of the day we went after some tail-end storms near I-80, and wound up on some very interesting storms with forward-flank gustnadoes or weak tornadoes.   Here is my write-up for the chase discussion group:

Our group endured a somewhat frustrating chase day as fast-moving cells moved through a sparse road network in central NE. The target area of Burwell, NE, worked out fairly well (northeast of a surface low and just in front of a cold front) as the initial activity went up in northern Custer County and moved NNE towards Brewster. We watched a couple of strong cells pass us on 91, just southeast of Brewster. The first one strengthened considerably as it continued to Atkinson at 45-50 mph. There was zero chance of staying close to it. We went back to Taylor and Burwell, then back to Taylor and north 25 miles to briefly see another storm and its meso blast by. Back to Burwell again, and we elected to go southwest to the tail-end storms in Custer County. As we approached Broken Bow, the tail-end had jumped south all the way to I-80. We were dealing with a primarily linear situation now, but the convection was a little behind the cold front and the strong south winds were not getting underneath the updraft bases at the surface. However, there were plenty of strong embedded and elevated mesos in the line. One of these prompted a tornado warning down at Cozad, and a tornado there continued to Oconto, reportedly. We placed ourselved east of Oconto and allowed the precip cores to get close. As the rain neared, a dusty spin-up was observed nearby to the south. A little later, on 40 from Miller to Kearney, we were just behind the gustfront and numerous funnels and dusty “tornadoes” were observed, primarily from just southeast of Amherst to a little northeast of Kearney. Were these really tornadoes or not — I don’t know —- they were briefly strong with dust-filled tubes which were beneath tight rotations at cloud base or beneath fairly-obvious funnel clouds. I think I’ll call them “gustnado/tornado hybrid tornados”. They were definitely not products of a classic supercell with an RFD, but were near the leading edge of the convection, on the interface of the storm outflow against the very strong and moist southerlies. At one point North Platte had sustained winds of 50 knots from the west while the station to its east was south at 30 knots. The convergence along the front was tremendous.

We ended the chase at Kearney, where spider lightning streaked through the mammatus clouds in the waning light of dusk.

Bill R., with Brian M., Chad Cowan, Danny Gonzales and Kinney Adams

May 31—there was little or no risk of storms in the Plains, and the next day’s target looked to be up towards Cherry County near the SD border,  We drove from Cozad north and northwest and had a leisurely tour of the Badlands during the last couple hours before sunset, and it was quite pretty!  We found rooms in Kadoka.

June 1—Well, the original thinking for the SD/NE border was obviously not going to work when we looked at data this morning.  We had to be back down south along I-80…maybe even farther south!  So, we hurried down 61 to Ogallala.  Here is my chase account for June 1:

On Wednesday (June 1) my group (with Chad Cowan and Danny Gonzales) targetted the I-80 corridor around LBF. We got out of Kadoka, SD, at 10:30 a.m. and hurried down 61. By the time we reached Roscoe, NE, around 3:00 p.m., convective initiation was just beginning to the northeast of McCook. A cell managed to break through the cap and go severe near Eustis, in Frontier County, and we were able to easily get right in front of it. The base wrapped up very nicely and threw some 1.5″ hail at us. A tight rotation produced a brief funnel cloud just north of Eustis, but the storm then gave up on that idea and weakened considerably.

Stronger convection beckoned to our SSE, in NC KS, and some chasers were lured towards that. We went east through Elwood thinking that we should be on the KS stuff, but then turned around as our original supercell was perking up considerably once again. I figured that tornado chances should be a bit higher along the warm front, near I-80. Our storm’s updraft base was stationary, very close to Cozad. We drove west from Lexington a few miles and had a perfect view of the classic supercell structure and wall cloud. The storm did the “big suck” with ESE winds racing past us at 35 mph, and the wall cloud spun a little and it looked like a funnel was dangling diagonally for a time behind some precip curtains. A small cell crashed into ours and rained on us, and obliterated our view of the base. We went east into Lexington and then west of Lexington again as the precip cleared and the base emerged again, but the cell looked worse for the wear and went downhill. Another strong updraft went up a little east of Lexington, near Overton, but the low-level air was coolish and worked over and it did not appear to be surface-based.

We called it a chase around 7:30 p.m. and headed to BBW for dinner, and then to VTN for the night.

June 2—we worked our way north and northwest into western SD—here is my chase account:

The better risk for tornadoes on this day was east of the Missouri River in the Dakotas, according to SPC, in part due to strong 850 winds late. But, the cap was quite strong and there were no boundaries for low-level convergence in the eastern Dakotas. We had to venture north and west from Murdo after lunch, I figured, if we were to see convection before sunset. An approaching trough at upper levels was cooling the mid-levels and weakening the cap inn western SD during the late afternoon, and a “lee trough” at the surface extended from about Lemmon to Rapid City. Dew points on the east side of the surface trough were 65F-67F, but the southeast winds were weak.

From Eagle Butte we drifted west to Faith, and we finally saw some perky cu west of Faith around 23Z. A very pretty line of convection went up in the deep blue South Dakota sky from near Usta to McIntosh. The strongest cell was to our north, between Isabel and McIntosh, and we could easily see a large RFD cut and some shallow lowerings. One or two other updrafts spun hard along Hwy 20 near Glad Valley, but these were scrawny. The biggest cell was heading away from us into ND, and I was reluctant to follow it given our leash (we had to start heading back to OKC on the 3rd), and its tornado potential seemed to be slim. The updrafts just to our west, west of Isabel, continued to struggle, so we elected to abandon this area and to dash south for the severe storms moving northeast through the Badlands. We had only an hour of sunlight remaining, and the Badlands storm was 120 miles away, but at least we might get a decent lightning display.

The storm complex held together and gave us a fairly good light show, both on the approach and at our stop just west of Hayes. The warning mentioned tennis ball-size hail and strong winds, and the structure was impressive in the lightning flashes. The cell(s) weakened a little just as it neared. Southwest winds picked up very quickly as the rain began, and we made our was into Hayes and found some cover for the vans. The wind in Hayes gusted to perhaps 50 mph and the hail was only marble-sized. The main storm core passed by just to our west and north.

June 3—This was the final full chase day for Tour 4, and we were in Murdo, SD, and had to be back in OKC by early afternoon the next day.  So, we had to dive south, and fortunately there was a chance of strong storms along the way, in NW KS.  We chased some high-based convection northeastward from Russell Springs to Oakley, and then stopped just east of Angelus, KS, just before sunset.  Precip beneath a line of storms to our west and northwest was lit up orange by the setting sun, with occasional to frequent lightning behind the tall church steeple in Angelus.  It was a photographer’s delight, and the guests were amazed at the deep colors and stormy look to the sky.  Stay tuned for the great images!

June 4—drove from Salina to OKC for the end of Tour 4, and prepared the vans for the next tour.  Total mileage for the 7-day Tour 4 was 3645 miles.

June 5—Tour 5 was ready to go from OKC around noon.  A strong upper-level trough was forecast to swing NE-ward into MT and the Dakotas the following day, so we had a lot of driving to do.  We blasted northwest to Woodward, Dodge City, and into eastern CO.  We viewed a high-based junky cell near Eads, and continued north to Fort Morgan for the night.

June 6—the upper-level trough was approaching eastern MT, but was arriving a little late to impact the moist boundary in SE MT.  Here is how we played it:

Our group left Fort Morgan mid-morning, unsure where to target along the E-W CAPE axis from Billings to north of the Black Hills. The strong upper level/negative tilt trough was timed a bit late, and convection was not expected until near or after sunset (if at all) in SE MT. Given this and that we wanted to chase the system east towards ND/MN the following day, I decided to forget about the Billings-area (near the surface low) and to hope for something strong N or NE of the Black Hills. Some high-based junky stuff formed in NE WY and moved over the Black Hills towards RAP, and we intercepted it along 34 around Union Center. There were occasional heavy cores, and it was warned for strong outflow winds. An inflow band from the NE persisted for a while and the leading edge exhibited some structure. A shallow lowered area developed on the leading edge, but overall the base was high and the storm was undercut by its outflow.

It weakened towards Faith, but sporadic lightning activity kept us awake along the empty western SD roads. Brian and I managed some photos of the “tower lighting” effect with multiple “strobe” branches from a tall tower near Faith. At our pit stop in Faith, dust was getting kicked up and the temperature was 91F (in light rain) at 04Z due to heat burst effects.

Bill Reid, with Brian Morganti, Jennifer Dunn, and Woody Watson

June 7—this day began in Mobridge, SD.  With the potent upper wave moving through the western Dakotas, we felt that supercell and tornado chances might be pretty good just northeast of the surface low, which would be near Fargo by late afternoon.  But, moisture return was not that good into MN and the cap was strong, so I decided to wait along I-94 east of Bismarck for storms behind the surface low.  Here is the account:

Our group chased a strong cell/marginal supercell east along Hwy 34 in southern ND, from Hazleton to Napoleon and all of the way east to I-29 at sunset, where it pooped out. The storm was relatively low-topped and non-severe, and was never warned on by the NWS. Highlights were strong winds, blowing dust and heavy rain between Hazelton and Napoleon, and some moderately interesting structure with the updraft base on the south end, especially around Marion. It was outflowish by the time we got on it at Hazelton. The storm was mocing east along 34 at 40 mph and was kicking up large plumes of dust off of the bare fields. A tiny “gustnado” was kicking up spray on one of the many lakes in the area.

I elected to disregard the better tornado prospects (east of Fargo and Grand Forks) on the northeast side of the (E ND) surface low, as dew points there were less than impressive and models indicated a capola bustola in N MN. They were correct. We wound up along a E-W boundary across southern ND, behind the low, which separated west winds on its south side from N and NE winds on its north side. Our cell was the lead cell of three—the middle cell had a couple of tornado warnings, but no tornado reports, apparently. A tornado was observed with the trailing cell, between Dickinson and Bismarck.

June 8—From Wahpeton, ND, we had to blast south on I-29 to reach the cold front boundary, which was drifting southward through southern IA and southeast NE.  As we reached Omaha, a couple of CBs went up to our east along 1-80, about 50 miles away.  We considered going after these, but had problems with road closures due to flooding and construction near Glenwood.  We blew off those cells and continued south into NW MO, and then SE NE, and finally NW KS.  CAPE values were quite high here and models indicated some big storms before dark, but they did not materialize.  We had dinner in Holton and stayed in Topeka for the night.

June 9—We thought that this might be a day with tornadoes in NE KS, north of Topeka, but the weather gods said NO.

Here is my NOW post made early-mid-afternoon:

Our group is a little NW of TOP, at St. Marys, moving north towards Seneca. It would appear that much of the juxtaposition stuff is juxtapositioning near the KS/NE border towards 00Z. The 19Z surface map shows the surface low between Emporia and Salina, with nice ESE winds from Falls City to Hebron. Falls City dew is 72F.

HRRR makes a big storm by 21Z across the border into SE NE, along a E-W boundary with cool ENE wind on the north side. A little later storms go up along and just south of the KS/NE border, according to the latest RUC, on the primary warm front which separates the ESE winds from the southerlies in NE KS. The RUC shows a pronounced moisture convergence bullseye near Seneca, KS, at 00Z.

The satellite pic shows a clump of stratocu in and around Nemaha and Brown counties, so we’ll head on up to Seneca. Skies have cleared out nicely here, with just a few cirrus and stratocu. The smoke situation isn’t too bad —- but it is slightly murky with haze.

We spent a couple of hours in and around Seneca, and waited.  We waited at the church in St. Benedict, and waited some more.  Storms did not develop as expected.  Here is the chase account:

We targeted the Seneca, KS, vicinity, just northeast of the surface low.  Everything appeared to be in place for a supercell with excellent tornado prospects, but deep moist convection was absent in the favored target area. By about 6 p.m. storm towers developed near the Missouri River, two counties to our east. It appeared that if we were to observe a storm today, that this was our best bet. We played catch-up on the Saint Joseph storm, and as it was moving NE at 25 mph we caught it near Stanberry around 7:30 p.m. This was precisely when the storm quickly dissipated. It had been supercellular briefly with an impressive couplet as we honed in on it on its southeast side, but I think it encountered a cool and stable low-level air mass, perhaps the result of previous convection now to its east.

I then waffled between heading SE to strong/severe cells around Gallatin, MO, or going back WSW towards the new strong stuff (120 miles away) west of Topeka and moving into my original target area. I decided finally on the (much closer) back-building cells between Gallatin and Cameron. These were never able to get particularly strong or well organized, at least on the back-end where we were (baseball-size hail was reported with a big cell a county or two to our east). We watched a brief CG display and heard a few hailstones hit the vans, and that was about it. Pesky low clouds frequently blocked our view of the storm towers, so we limped into the Cameron motel with little to show for the day.