Friday, July 8, 2011

06/19/11 Nebraska Supercell Extravaganza


Supercell along I-80 near Kimball, NE

Sunday, (June 19) I chased once again in western Nebraska as conditions seemed to be coming together for a possible tornado outbreak and severe weather. This chase day looked to be the most "favorable" during my entire chasecation. It's a day I will look back at as I learned quite a bit. After rooming the previous night at a Best Western in Kearney, NE I ended up targeting North Platte, NE on this chase day. A warm front in Nebraska in June usually means trouble folks! I headed west on I-80 to my target arriving there around midday. The atmosphere was quickly loading-up by early afternoon. Along I-80 in western Nebraska the atmosphere was getting rather ripe along the warm front with 3,000J/kg of CAPE present, 0-6km shear nearing 50kts, and rich-low level moisture with dew points around 60°F. Lets also not forget strong low-level shear with SRH 250-300m/s2, a supercell composite around 16, and low LCL's around 1000m. As the atmosphere quickly destabilized throughout the day the stage was set for a severe weather outbreak. I changed my mind on my original target around midday thinking I could get a few supercells and maybe even tornadoes farther west near Sidney, NE before the "cap" broke around the McCook, NE area by evening. I ended up heading west on I-80 chasing a supercell near Kimball, NE (first storm of the day). I chased this storm for most of the afternoon slowly working my way back east along I-80 toward the evening target-area. This supercell was rather photogenic around Kimball, NE as it gained more and more rotation as it worked east. I shot many photos of this slow-moving tornado-warned supercell and took some time-lapse video as well at this moment around 4:00pm. By late-afternoon however I noticed I had to ditch this storm as new convection looked to ignite along the warm front and may hold a little more tornadic promise. I headed east along I-80 reaching North Platte, NE by 6:30pm. I was probably about a hour too far behind as supercells erupted to my southwest near McCook, NE. If only I pulled the trigger a hour earlier! Furthermore, knowing I couldn't get to those storms before sunset I turned my attention to a developing supercell northeast of North Platte, NE that visually was intensifying. It quickly went tornado-warned so I watched this supercell rotate for a bit with a well defined wall cloud and lots of weird motion along the ground. Was there any spin-ups with this storm?! Good question! I really have no idea as it was rather messy below the base. I later gave up on this storm as it weakened and called it a night annoyed that I missed the main show to my southwest. Next time I won't get so "greedy" early-on in the day since those storms I missed produced several tornadoes along the warm front and spectacular structure as well. I shook this one off and went to sleep hoping for better things the next day. I've added photos and video of the two supercells I chased below:

Now that's some deep-moist convection right there...
Along the NE/CO border!
First view of the supercell near Kimball, NE
(pretty crappy at this point)
View from the north-side of the supercell... (mammatus)
Wide-angle view now she's getting
her act together...(wall cloud)
They don't call this area the
Sandhills of Nebraska for nothin'!

Yep, here's the Colorado sign too!
Supercell really getting going now as the wall cloud
is nearly on the ground at this point...
The first of many wide-angle shots of the supercell!
A spinning top here as southeast winds were
gusting to 25mph at this time

Supercell moving over I-80 east of Kimball, NE
Maybe my favorite shot?!
Many other chasers were along this exit off I-80
as
well including fellow chaser
Brad Goddard
!
Supercell #2 northeast of North Platte, NE
Wide-angle shot here...
This supercell looked good for about 20min...
(lots of chaotic motion under the base however)
I've added a YouTube time-lapse featuring both supercells (above)

I've added a short YouTube clip of the North Platte, NE
supercell from my GoPro as well (above)

That wraps up this chase day. I really needed a tornado on this day as my chances of seeing a few more tornadoes before the season was over were quickly diminishing! Than again I had no idea what the next day may hold at that point! I'll update with that post shortly. Stay tuned.