From Multicell Garbage to Electrical Spectacular
Northeast CO, 11 Jun 6.
SHORT: Somewhat scenic, high-based, daytime multicell with supercell attempts along I-76. Spectacular anvil crawlers after dark.
LONG: We headed up I-76 toward the CYS Ridge target area and waited on a hilltop N of Ft. Morgan. And waited, and waited, and waited, in the baking sun. Storms were forming in a convergence zone between DEN-FCL, but we ignored them for a long time because of weaker moisture, hoping for development to our N.
Finally we grew impatient, and with eyes still trained longingly to a northern sky devoid of deep moist convection, we decided to backtrack toward DEN to investigate that activity. After a couple of hours of observation, we noticed development way off in the distant N, on the N edge of my original target area, but it was too late. I knew a good supercell was possible up there in the better moisture, and was hoping that whoever was there enjoyed a good show. Apparently such was the case. Chalk up another testament to the virtues of sticking with your forecast area.
In the meantime, we relaxed on a well maintained dirt road 7 NW Hoyt: just us, the wind, occasional distant thunder, and a horde of small black beetles migrating eastward as if to run away from the slowly approaching storm.
For a short time, this was a place to rediscover the wide views of Great Plains skies, treeless and filled with the tumult of convective power, hardly a building or wire in sight. It wasn’t hard to step back in time and envision this sky seen by the pioneer families venturing for the first time into this big and open landscape, storm and mountains looming in the near and distant west, obstacles temporary and permanent looming above and beyond, respectively, compelling a decision to forge forward or to turn back, or perhaps even to set root here in a place that was, at once, starkly beautiful and unmerciful.
So we observed and imagined, simultaneously appreciative yet wishing for much more from the atmosphere. A dense core with occasional “rainshaft-nadoes” gave someone some valuable rain as more thunder crackled overhead from unseen anvil crawlers. Our storm(s) developed a fair sized updraft base and an inflow tail and tried to rotate; they may have, weakly, before eventually gusting out.
A new storm formed along the NE edge of the complex near Brush, with a somewhat colorful shelf cloud. Still, we were disappointed as we headed back into Fort Morgan, wandering the roads between there and Brush in vain attempt to find short-fuse rainbow photography views unobstructed by trees, wires and buildings. [Yes, we found perhaps the one area of eastern CO where this is a major problem.]
However, as often is the case, our disappointment turned to elation. We finally found a fairly open view about 2 E Ft. Morgan. A few nice sunset photos were followed by an absolutely dazzling show of anvil crawlers and mammatus from dusk to dark. The back side of this MCS was strobing almost continually, with at least 2-3 good crawlers per minute shooting across a sky of mammatus and ebbing twilight. I shot more crawler photos in 30 minutes than in all my years of chasing prior as the last evening light faded to night. Occasionally a CG would erupt beneath, but offset about 45 degrees, from the locus of a simultaneous crawler discharge.
Much of the action originated from the same region to the E or ESE, as the complex slowly receded, making the choice of sky sector an easy one. Still, even a 17-35 mm lens wasn’t enough to capture some of the most brilliant discharges that swept almost from horizon to zenith and beyond, while reaching north and south in search of electrical equilibrium. About half the crawlers were accompanied by a single, staccato CG, with few or no forks (still another fine example), reigniting a longstanding curiosity I’ve had about the connection, if any, between the two forms of lightning strokes.
A short drive back to Denver and several days of R&R followed before the storm intercept vacation would wrap up.
===== Roger =====
Cumulonimbus Barfus Maximus Nebraskus
Southeast WY, West NE and Northeast CO — 10 Jun 6
SHORT: Long drive for a little bit of good photography, a short-lived/high-based supercell near BFF, no legit tornadoes, and a lot of dusty outflow between east WY NE Panhandle and NE CO. Abundant small hail found after isolated high based storm near Cope CO.
LONG: Although there was enough shear for supercells (and we did see one), one of my fears was that the large scale ascent ahead of the west WY trough may arrive too soon. It did.
At noon MDT, the sky over east WY (behind the dryline-like surface feature) began filling in fast with high-based, fuzzy storms all-quadrants. The first of many of these was visible as we headed into Lusk WY, at 12:26 p.m. MDT (looking SW). Note that time, dear reader. That’s too blasted early!
Soon, more high-based storms formed all around east WY, spewing some beautiful CGs but also a lot of cold outflow. This is when the realization hit that the chance of seeing a legitimate tornado for us today was near zero. A patriotic, red-white-and-blue windmill framed one neatly lit cell S of Lusk, and then it was off to the races to get and stay ahead of the outflow.
Turning ESE out of Torrington, we noticed a high based storm distant ESE, near BFF, with a broad, shallow wall cloud. [No photos...I was driving, it was distant and did not impress me from that angle.]
As we crossed the Nebraska line, the pretty lighting of the arcus behind us caught our interest more than the high-based supercell near BFF, and we stopped to get some panoramics of the former (looking W and the companion shot looking WNW).
A few miles further down the road, near Morrill, we heard that the lofty little supercell to our ESE was TOR warned! It did have a legit meso that wrapped some precip filaments around its W side, but there were three problems:
1. A base way too high,
2. Undercutting from its own storm scale outflow, and
3. A building, mesobeta scale outflow surge about to smash to smithereens whatever remained of the storm.
After turning S from Bridgeport toward SNY we noticed a pronounced blocky lowering with a pendant, conically shaped cloud feature centered beneath. The problem was: It was behind the arcus cloud, made of thick scud, and not rotating. Shortly after that we passed some chasers parked nearby, atop a hill, on a side road. Elke said, “Somebody’s going to report that as a tornado.”
She has a keen sense for the presence of incompetent observers, because not 30 seconds later, the NWR alarm sounded with a tornado warning…for that storm, based on “spotters reported a developing tornado” in that very location. We pulled over and I took a few documentary photos of the sorry excuse for a “developing tornado” as it quickly devolved from solid scud into ragged garbage, then went away. The whole feature lasted less than two minutes and was about as tornadic as hoarfrost on the beard of a buffalo.
We stayed to do some equine photography with the arcus in the background, in a classical Great Plains scene. A herd of very friendly horses, initially on a hilltop about 1/4 mile away, galloped right over to beg our company and, in one case, vigorous human scratching of its apparently itchy forehead. Their company was all too brief. Within minutes, the gust front that had been several miles away overtook us with thick choking dust, 58 deg F surface temps, and howling NW winds — ahead of the arcus. Horses and humans cleared the area in a hurry.
Meanwhile the “tornado” warning suddenly vanished from NWR. Imagine that. “Developing tornado” — my _ss! Whoever reported that needs to go back to basic spotting class to be taught that tornadoes actually do rotate. Oh, and they don’t tend to occur behind arcus clouds rising over deep, cold outflow. Duh.
Southward to Sidney we cruised, stopping briefly to look at the visual manifestation of a LEWP off to our NNE. Now, on rare occasion, *those* sometimes spawn spinups, but this one got undercut so fast it didn’t have a chance. Maybe others up the line toward Cherry County did, but we had no interest in racing east for hours across NE trying to keep ahead of a deep, mesobeta scale (and growing) blob of surging outflow that felt like some weird mix of Saharan particulates in Antarctic katabatics.
“Spotters report a line of thunderstorms capable of tornadoes” was the last thing we heard from that NWR as we roared off into NE CO, trying to find isolated development S of the horrendous pile of outflow. Dusty gusts near SNY may have been severe, causing us to struggle to stay on the road at times in a heavy, low-profile sedan. That said, I won’t venture an estimate since neither my estimates nor anyone else’s on this planet are reliable to within +-20 kt at those speeds.
N of Sterling we passed what appeared to me 5 or 6 TTU mobile mesonet vehicles and, just a little ways down the road, a non-DOW portable radar (Howie?).
We did intercept the back side of a small SVR-warned Cb near Cope that had a pretty backshear as viewed from the N, but also, a very high base. Precip curtains prevented us from viewing the updraft region until we let it get SE of us, and man, was it ever high based. A good deal of hail that was marble sized (but conical or candy-corn shaped) covered the ground along US 36 in the Cope/Joes area, on both sides of the Washington/Yuma County lines.
We ended the storm day with some dinner in Limon, and photography of the old grain elevator under sunset-lit ACCAS. Cold NNE winds soon blasted us there, two hours and 100 miles removed from our last encounter with the same outflow current near Sterling. Even in the north suburbs of DEN, after 11 p.m., we got a shot of the outflow pool sloshing in from the ENE. That gave us nearly 12 hours in and out of outflow from the same huge mess of storms.
===== Roger =====
Volcanic Tower and Convective Power
Northeastern WY, 9 Jun 6
SHORT: Abundant wildflower, Devils Tower and convective power photography. Intercepted tornado warned supercell between Sundance and Newcastle WY. Probable tornado observed, numerous daytime CGs photographed. Great dinner and sunset.
LONG: This was one of the finest Great Plains chase/photography days I’ve ever had, with or without a probable tornado in the western Black Hills of Wyoming.
The day began with a great breakfast cooked by the 81 year old female proprietor of Bob’s Cafe (or “Bob Afe,” depending on which side of the sign you view). We highly recommend this place in Belle Fourche — a 1940s/1950s era diner where the locals have gathered for generations. One of these locals we befriended was a SD native just returned home from many years in Maine, a keen and highly talented outdoor photographer named Bob Clements. We ended up spending an hour or so with Bob, talking photography and getting the grand tour of his future gallery, in a musty old downtown brownstone that he is renovating himself. If you ever make it to Belle Fourche, and Bob’s gallery is open, check it out.
Next came the drive to Devils Tower, which conveniently was on the way and very close to our forecast area of interest in SW SD and NE WY. We spent the midday hours photographing wildflowers and their surroundings, horses, sweeping landscape scenes across verdant valleys, and numerous scenes around the tower itself.
On the way to the tower, we noticed anvils streaming off convection unseen in the distant SW. Without live radar data, I still was (correctly) confident this was the result of high-based and rather moisture-starved storms around the Bighorns. An outflow-reinforced cold front had moved through, but not too cold to allow storms to form once the sun heated the air mass enough. The northeast and east winds behnd the front also would advect more moisture into the area with time. For the time being, though, I knew we had a little while to hang out near the tower and wait for better storms to form, closer by. So we did.
We found a great overlook a mile W of Devils Tower where only one other person came by in an hour, great for afternoon shots of the tower with not a single human artifact of any kind in view. Under the lazy drift of floating cumulus clouds, the tower’s appearance never was the same from any given minute to the next, and we relished its many moods of light and shadow. I also shot time lapse video of the tower in the right foreground and distant cumulonimbi building in the background, over SD.
Those weren’t our target storms, though, so we stayed put and experimented with other ways to view and photograph this amazing volcanic landmark. Patiently we waited for more storms that had formed over the Bighorns region to move our way and into better moisture. When the anvils moved overhead and the western skies grew dark with the looming bulk of robust, newer storms, it was time to go.
While driving about 10 W Sundance, we heard a SVR from RAP for what was then a tail-end cell over NW Weston County, moving E. Within a minute or two we found a high overlook from which we barely could see the updraft base about 25-30 miles SW, a dense core to its N, an inflow tail to its SE, and ragged attempts at a wall cloud.
We raced toward Sundance to get in intercept position, deciding to go SE of Sundance on the road to Newcastle, in order to stay ahead of the cell. It was evident the storm was a supercell, now right-moving E toward the unchaseable morass of the Black Hills. The roads were few, and the gamble was this:
1. Go SW of Sundance on WY-116 toward Upton and get closer to it faster (but spend much less time watching it) or
2. Head SE of town into higher terrain, temporarily losing view of it around Sundance and Inyan Kara Mountains, but getting in position to watch it longer from more of a distance…if we could find a good vantage looking SW.
We deiced to go with option 2, about the time a TOR warning blared through NWR. We were entangled with the town of Sundance at the time, unable to view the base due to buildings, trees and hills. For the next 16-18 minutes we couldn’t see under the base S of Sundance either, thanks to rolling higher terrain W of the road.
I was wondering if my eastern decision would hose us out of a chance to see a tornado, while driving mile afer mile with the SW sky obstructed. This was very frustrating, but the annoyance proved to be blissfully ephemeral. Motoring S on the spaghetti road, through the rolling western foothills of the Black Hills, we finally found a good westward viewing spot 5 NW of “Four Corners.”
The supercell had something of a wet, outflow-dominant appearance when we first took position. Soon it sported a very low wall cloud 10-15 miles to our WSW (wide angle view), which intermittently wrapped in rain, then re-emerged. To its ESE (our SW-SSW) a heavy and elongated rear-flank core appeared, along with other, newer updraft bases. This gave the whole process the look of a supercell evolving into either a deep LEWP notch or an HP “Pac Man” type storm, with the mesocyclone in the inner corner of Pac Man’s mouth.
At times it looked like a “meso on the ground,” though it was hard to see true ground thanks to a gentle rise about 7-8 miles to our W. One thick pile of tail cloud material appeared to form near the ground and race southward into the wall cloud. Meanwhile, all sorts of wild looking bands and patches of cloud material overhead and into the storm, along with the green landscape of grassland and broken short pine, and an astounding barrage of strobe-style lightning bolts, made for wonderful wide-angle landscape photography.
A small core formed SSE of the meso and grew bigger, merging with the rear-flank (wrap-around hook) core until the meso itself became a deeply occluding notch. The strengthening inflow felt cold and was — 65-67 deg F, but it was from the E, and our elevation was 5700 feet. Normalize those temps at lower elevations, or put them in at our elevation on a sounding diagram, and the thermal characteristics actually look pretty nice for supercell inflow.
The lightning with this storm was impressive, even for this 21-year storm intercept veteran. Dozens of CGs popped over the valley and ridges between us and the meso, but at a safe distance. Between Elke and me, we captured 20 or more in our hand-held photos, thanks to the ridiculous repetitiveness of the flashes. Several times we each shot the same lightning strike using only a finger reaction to the first flash. But that’s not all. Get this: I was able to take two separate, all-manual photos of one CG (the first one linked above)! I’ve never done this before, nor heard of it being done. That’s how long the strobing lasted with some of them. At times, it was like a giant atmospheric discotheque over there.
What is it about the electrical layout and resistance characteristics of supercell storms that causes some to produce strobing lightning strokes one after another, each lasting 2-3 seconds, while others simply hurl super-quick staccato bolts hither and yon?
Meanwhile, the meso tightened up dramatically and shed some precip from its E side, forming another very low wall cloud, scud rising fast up the N side. The horizontal and differential cloud tag motions got rapid as well, more so than several tornadic storms I’ve seen; and I was beginning to wonder if this one could spin something up before it got rain-wrapped. Thick precip already surrounded the meso in every direction except NE-E, but fortunately, we were tucked in the “notch” ENE of it.
Cloud base rotation under the wall cloud also became obvious, and at times, quite intense, as seen through zoom lenses due to the distance. At 5:07 pm MDT (6:07 pm CDT) one very suspicious lowering — tapered, fuzzy and rapidly evolving — developed under the wall cloud and appeared to reach ground, though the terrain precluded irrefutable confirmation.
I ran to the car to get binoculars, which revealed this feature as a furiously rotating funnel, at times extending below the level of the low ridge in the distance. I managed to snap a few photos in between careful eyeball coverage, the best being one which also captured one of those strobing CGs by chance (here’s a super-enhanced version).
Was it a tornado? I’m quite confident despite the limitations of terrain and distance. Probabilistically speaking, I’ll say at least 90%. It’s hard to conceive otherwise given the persistence of the funnel, as well as cloud motions both internal and ambient to the feature.
By 5:10 p.m. MDT, a thick bear’s cage wrapped around the wall cloud from the S, leaving it a mystery what was going on behind the orbiting rain curtains. Something suspicious might still be apparent in this shot at 5:11 p.m. (super-enhanced contrast version), but after that, the whole mesocyclonic circulation got too deeply buried in rain to infer much.
We reeled off a few more CG-over-landscape shots, and the electrical action and cores started getting close (wide angle). The last CG that I dared to shoot instantly ignited an orange fireball on the next hillside. I didn’t want to be next, so in the car we went.
Forward motion of the storms began to accelerate, and it appeared an MCS was spontaneously developing all around us. With the only east option extending into the depths of the Black Hills, and the sky erupting into MCS ALQDS, we decided to call off the chase and head SSW to Newcastle for dinner and lodging. [Also recommended -- the Fountain Inn with free wi-fi, and collocated LaCosta Mexican Restaurant, with excellent steak-and-shrimp fajitas!]
After a great dinner we did some photography along WY 16, NW of town. This included a high-based, elevated storm in the golden light, near an old missile silo. As it moved toward its SE and to our S, a rainbow and some postcrepusculars became visible.
Clouds to the WNW blocked a lot of the best sunset light, but we enjoyed it immensely anyway. What couldn’t be photographed was the earthy-spicy smell of rain-washed sage, an aroma of life’s renewal rising from an arid land newly drenched, the joyful warble of hundreds of meadowlarks resonating across the Thunder Basin grasslands, the cool moist breezes carrying these scents and sounds to us and through us.
Back at the hotel I couldn’t resist taking couple of twilight and nighttime shots of their tornado shaped fountain, bathed in spotlights of alternating colors.
We had a long and amazing day, and slept very well that night… almost too well!
===== Roger =====