High Plains Drifter

3 Supercells in the Nebraska Sand Hills — including memorable late-night moonlit supercell near Stapleton, NE

I was hoping for just some decent storm structure for maybe an hour or so around sunset on this particular chase day… trying to keep my expectations to a minimum.  What resulted was one of the best storm photography moments I’ve had since shooting DSLR in 2005.  I observed three supercells, two of which I photographed extensively during their mature phases.  My chase day actually began in Thedford with a target of Ogallala in mind.  I arrived in Ogallala with upstream dewpoints in the 45-46 degree territory at Imperial and McCook.  I figured it would take about a 48 dewpoint to get a large area of ~ 1000 J/kg of CAPE.  That eventually did happen, and my main area of interest was along and just north of I-80 where the highest dewpoints appeared to be advecting toward strongest low level convergence.  This all seemed to be taking place just north of Ogallala.  I drifted west from Ogallala to Big Springs where I observed a bunch of virga showers from southwest to northwest.  I followed this junk east… sticking with it… because I’ve seen severe storms eventually be born out of this agitated high-based shower activity.  I got to North Platte, and by this point it was going on 6:00pm, with still nothing much to write home about.  I was becoming increasingly frustrated and was thinking this was going to end in a bust.  Small updrafts to the northwest struggled mightily.  That being said, there was still good south-southeast wind with 47 to 48 dewpoints feeding into this area of weak convection.  Knowing that the upper level jet was just beginning to impinge on this area, I knew I couldn’t just simply give up at 6:20pm in the evening.  Never do that unless it is totally obvious there will be NO STORMS at all!  In the back of my mind, I was imagining that a) April jet stream, b) good low level inflow, c) dewpoints in the upper 40s, d) good low level convergence/frontogenesis… and thinking that this could possibly yield a surprise.

An elongated cluster of storms was increasing in strength south of Thedford, and I followed this northeast from North Platte to Stapleton where I headed east on Hwy 92 to Arnold.  The lead storm to the northeast was initially the strongest, so I set after it first.  Eventually, it died between 7:00 and 7:20pm or so.  Then cell “Z1″ started to form at the southwest end of this cluster.

I was in great position for this.  At Arnold I went north on a county road and got some of my first structure shots of this newly developing supercell.  It was gaining on me fast, and since I wasn’t a fan of all the low clouds obscuring my structure view, I backtracked to the south to Arnold to get a little farther away from the cell again.  I did manage to get a few images of the cumulonimbus tower above some of the low level inflow tails.  Sunset was near as I made my way to Anselmo.  I took more county roads north and east of Anselmo where I photographed an ominous lowering/wall cloud feature to the north, however the contrast was kind of poor.  I did manage to capture a distant cloud-to-ground lightning flash with the lowering off to the left as the storm was beginning its demise.  By 9:00pm, the storm was racing off to the northeast, north of Taylor and I let it go.  At this point, I was satisfied that I got myself a supercell on such a marginal day and I was ready to call it a day and head to Kearney for the night.

But my chase had really only just begun.

I drove about 5 miles or so southeast of Anselmo on Hwy 2 when the next supercell formed to my northwest…northeast of Thedford.  The distant structure on the horizon was too good to pass up.  Problem was, I was so far away from this storm that I had to use a zoom lens on my D200, since I don’t have a fast, full-fame zoom lens on my D3 (I just have 14-24mm f/2.8 for my D3).  I took a couple wide angle shots with the D3, but the storm was too far away that it didn’t really fill the frame at all.  With the D200, I still use the 18-70mm lens which is only a f/4.5 at the focal length I was wanting to shoot at.  The D200 does not perform well at ISO speeds greater than 640 either, so that is always my limit.  Given that, I couldn’t do 6 second or less exposures to freeze the storm with what little astronomical twilight was left.  I did get a few images, but I pretty much cut my losses and resumed my drive to Kearney… or so I thought.  I then decided I wanted to look at the new NAM model for tomorrow’s chase forecast, which had just come in, so I pulled off the road to do a little model interrogation with IDV.  A quick glance at the radar revealed yet another storm off in the distant west at around 9:45pm.  Given my frustration with not being able to photograph that second storm like I was hoping, I felt like I had to redeem myself and get closer to this next approaching storm, since the lightning activity was increasing.  The full moon had just risen, too, so I was thinking that this could get quite interesting, photographically.

I abandoned the idea of driving all the way to Kearney and though of North Platte instead, since a) it was closer and b) I was 90% sure I would be chasing in KS tomorrow.  I drove east toward the approaching storm, which was now really looking good on radar, as well as visually with the lightning.  The moon was also just about to appear over some clouds it had been hiding under.  What proceeded after that… from about 10:15 to 10:45pm… was something truly spectacular.  I found an adjacent farm road to Hwy 92 and pulled off with a great view of this supercell.  Tall cloud-to-ground staccato flashes then began to occur.  I couldn’t believe it!  The tripod went up and I started firing away.  I was closer to this storm, versus the 2nd storm about an hour earlier, so I could use the D3 with the 14-24mm lens and fill the frame with ultra-wide compositions.  The results were nothing short of amazing.  It was perfect.  Everything about it.  The supercell structure — clean with no other clouds blocking the view — some soft front light from a bright full moon.  Standing in a farm field with NO powerlines, NO artificial lights as a distraction.  No other chasers (except Dann Cianca farther west on SpotterNetwork).  This sucker was over the sandhills!  Wow!!  And I had the right equipment to get the best images possible in this kind of light.  I was able to successfully shoot 5 second exposure frames…. the whole time.  Every single frame from this storm was 5 seconds.  5 seconds, f/2.8, ISO 800.  ISO 800 on the D3 is extremely clean, and I would have felt comfortable shooting even higher, but there was no need to.  The full moonlight was enough light with this fast equipment.  Of course, lightning in the storm itself provided additional illumination.  This was a dream come true!  I have always wanted to shoot supercell thunderstorm structure illuminated by full moonlight.  Oh yeah, and some of the cloud-to-ground flashes were quite spectacular too, coming out of this storm.  I finally let the storm go around 11:00pm or so and made my way to North Platte for the night.

Begin:  Thedford, NE
End: North Platte, NE
Day Five Mileage: 457 mi.
Trip Mileage: 2227 mi.

17 images from this shoot: