High Plains Lightning Festival

July 7, 2011 by · 1 Comment
Filed under: Summary 

Colorado-Nebraska Border Region
13 June 11

SHORT: Began in BFF. Waited in SNY. Avoided outflow-surfing CO/NEb border storms to intercept supercell near AKO, saw probably non-tornadic dust whirls with storm merger there. Fantastic twilight lightning display from elevated storms along border S of IBM.

LONG:
Elke and I started the day in BFF, targeting the general area of the CO/NEb border SE of there. I wasn’t particularly jazzed by the weak lower-tropospheric winds in the forecast, figuring outflow and/or storm splits would be a problem. Still, it’s the high plains in early June with adequate moisture, upslope flow and at least marginal shear. The answer? Be there.

We waited a good, long time at a hilltop outside SNY, just NW of a dryline that eventually would fire up a tornadic HP supercell in the horrible road network and terrain of the Sandhills. We saw those towers to the distant NE, but chose not to pursue given the great difficulties involved with storm intercepts in those parts.

Meanwhile, we listened to meadowlarks and, on radar displays, watched chaser icons on SpotterNetwork zigzag back and forth across the area in impatience as the lack of focused action. Fuzzy storms began to fire between the Laramie Range and Cheyenne Ridge, which was no surprise; their distant bases were so high we could see them from SNY. I wasn’t impressed. Red dots converged on I-80 and headed W. We sat, waiting and hoping instead for dryline development to access richer moisture to our SE and E.

Finally, off to the distant SW, two storms erupted near and N of the Palmer Divide in Colorado. This was near the very southern fringes of our forecast area; but as nothing much was happening with the dryline nearby, and the storms were reachable, we decided to go have a look. Along the way SW, through the convoluted maze of roads that is Sterling CO, the southeast storm attracted quite a few chaser icons. The NW storm didn’t, was closer, and was in a similar environment; so we headed toward AKO to intercept it.

Alas, along the way, the SE storm calved off a big left-mover and died! Moreover, the left mover shot toward the inflow region of our target storm like a torpedo hell-bent on mutually assured destruction of both storms. Briefly, we got a view of the NW supercell’s mesocyclone area to our WSW before the left-mover’s core arrived; and it looked like a somewhat higher-based version of a North Texas HP “Stormzilla”. This meant big hail; so it was imperative to get S fast.

Yet there loomed the left-mover over the road to our S, likely bearing ice bombs also. It got there as we did, just S of AKO. The two storms started to merge overhead, and in the tiny gap between their cores, two strongly rotating dust whirls appeared less than a mile to our W, about 3 minutes apart. [I was driving and driving hard, so…no photos!]

Though a narrow, ribbon-shaped updraft had formed overhead at the merger location, we could see no obvious rotation in it. I attributed the whirls to gustnado-like vortices being stretched where the two gust fronts met. We maintained an equatorward bearing, encountering only marginal severe hail at best (to our relief).

Arriving just S of the combined storms, which indeed were killing each other, we photographed the dying supercell across rain-drenched corn stubble S of AKO. It was good to see Steve Hodanish and to swap Hodo stories with a co-worker of his, and also, to talk with a few other friendly storm observers whom I hadn’t met before. Yet we were essentially stormless, parting ways and headed back toward our various bases for the night. All that was left, for now, was outflow spinning a windmill under a dark and stormy high plains skyscape.

We headed toward lodging in the Nebraska Panhandle, soaking in the sights of Pawnee National Grasslands in anticipation of spending a couple of upcoming non-chase days of roaming around some of our favorite haunts around the Black Hills, not counting on any more atmospheric excitement. As good fortune sometimes plays on previously under-performing storm days, the night brought about an unexpected–and most welcome–show of splendor that made our night!

A short line of elevated and high-based thunderstorms erupted over the WY-NEb border region atop the outflow pool from all the late-afternoon activity, and moved SE across the southwestern Panhandle and across the Cheyenne Ridge. Evening storms like this in the High Plains can spark profusely, and these absolutely did! We found a vantage just over the CO/NEb border S of IBM (Kimball, not the company) and began shooting away at the approaching spectacle. Assorted forked and in-cloud displays slashed across the fading twilight, their reports blasting resonantly across the wide-open landscape. Soon, some cloud-to-air discharges flickered forth, followed by yet more (and closer) sky-splitting CG action. Wow…what a show!

The lightning was getting too close, though; so we drove through the translucent core of the thunderstorm line a short distance into IBM, crossing a few miles of small hail (with almost no rain!) along the way. I’ll never forget the sight of countless thousands of little white hail balls in the high beams–cascading dots of brightness, the only form of light shining back at me along that dark High Plains highway.

After securing a motel room near the edge of town (like we like to do), we noticed the sparkling display still underway to our SE, and headed back out past the E edge of town for a little crawler-lightning show in the trailing precip region. And with a few more flashes to light up the midnight hour across the western Nebraska prairie, bedtime drew nigh, our storm-hungry palates duly satiated. I had very few lightning photos to show for 2011 until this night, when the heavens unloaded electrical gifts one after another in a most dazzling and appreciated fashion.

Birthday Supercells in Northwest Nebraska

June 9, 2010 by · 1 Comment
Filed under: Summary 

near Harrison, NE, 21 May 10

SHORT: Intercepted 4 supercells, 2 after dark, near Harrison NEb, with 2 funnels from twilight storm S of Harrison.

LONG:
My two main forecast areas on this day were in eastern Colorado, for any storms that could form and move ENE off the Front Range or eastward-extending ridges (Palmer and Cheyenne), and of course the classical upslope play into the Laramie Mountains. Since I began the day in Russell, the CO target was much closer, and more probable to reach by convective eruption time. The idea was to pass through, and if it looked dead, continue onward into SE Wyoming or Nebraska.

Unfortunately I got stuck at a long construction delay between Burlington and Wray, where US-385 is down to one lane with a pilot car driving 15-25 mph for about that many total miles. After getting out of that horrendous mess, I thought my Wyoming/Nebraska hopes were ruined, so I photographed an abandoned farmstead for a bit S of AKO, while waiting for storms to fire in northeast Colorado. The air mass kept looking too stable and stratified, and I gave up once storms E of the Laramie Range began to sustain themselves.

Unfortunately, because of the long intervening distance needed to intercept the resulting supercell, I never made it to the Wyoming phase of its life cycle, when the structure was best. Instead I cruised N from Mitchell on NE-29 to get ahead of the storm, knowing it would be moving into gradually more stable air. A portion of the legitimately scientific V.O.R.T.EX.-2 fleet came up 29 right behind me, along with some pseudo-scientific vehicle with a bogus-looking “TORNADO AND HURRICANE RESEARCH” sticker prominently plastered thereupon. I felt like stopping to ask the “TORNADO AND HURRICANE RESEARCH” crew what papers they’ve published with their “RESEARCH”, but knew the answer, and more importantly, had better things to do — namely, observe the supercell.

Lightning activity above me, in the anvil, was increasing, so I got back in my vehicle. Not a minute after I did, I happened to spot a CG hit within less then 50 feet of that “RESEARCH” vehicle, and about half a mile downhill from me! It even looked like the lightning might have hit them. I started the truck and was throwing it into gear to rush to their aid, when they abruptly pulled out of their spot and zoomed southward past me. It was a very fortunate thing none of them got struck! One of these days, however, under less atmospheric duress, I intend to query such crews in the field and find out about the nature of their “RESEARCH” publications. Anyway…

This shot fairly well represents my view of the old Torrington storm as it scooted across the border into Nebraska. At times it did develop weakly rotating, scuddy wall clouds, but its encroachment upon more stable air yielded the expected result with time ( here shown as a higher, flatter wall cloud with precip-filled occlusion-downdraft slot, behind a sticknet). That storm moved N and NE of me, and I prepared to head to Harrison to look for lodging.

Meanwhile, I parked for a spell to listen to the cheerful choruses of western meadowlarks and breathe the refreshingly rain-cooled High Plains air behind the first storm. V2 left the area, and in the twilight, a new, small supercell formed along or just a shade N of the outflow from the other one, SW of Harrison and about 15 miles to my WNW.

Rather quickly, some cloud-base rotation and lowerings developed under a broad, elongated updraft area, followed in quick succession by a skinny, scuddy funnel (deeply enhanced crop-n-zoom) and then a lower, more robust-looking and separate funnel (enhanced crop-n-zoom). Both of those funnels were quite transient, and I could not detect any dust or debris at the level of the (wet) ground beneath. If either was a brief tornado, it was too weak and short-lived to count as such, so I probably still haven’t seen a tornado on my birthday. Still, I’m glad to have had the experience.

The twilight supercell moved too deeply into rain-cooled air left behind by the first, and weakened considerably. I got a room at the only motel in Harrison — the Sage Motel, a friendly if rather forlorn and cramped place — and called Elke and my kids. One highlight of the day was my daughter and her friends singing “Happy Birthday” to me as a quartet serenade!

Meanwhile, two new supercells popped up in Wyoming, SW of town, headed that way! After getting off the phone, I wandered a few miles W of town to watch the nocturnal supercell pair move quickly past, their structures faintly illuminated at times by in-cloud lightning. I attempted photography, but it was just too dark out there, the lightning too faint. The rear-flank precip core of the second storm hit Harrison, but without severe wind or hail.

I had to be in Denver the following night to meet Elke and prepare for her mom’s public memorial on Sunday the 22nd, so the potential (and realized!) major tornado day in northeastern SD was too far for me to chase. Instead, on the 22nd, I photographed morning fog in the Pine Ridge area N of town, then drove from Harrison to DEN, stopping for a pleasant hike and photography excursion Agate Fossil Beds National Monument along the way. Meanwhile the ultimate tornado-feast was about to begin for other chasers 250-300 miles to my NE.