July 29, 2007 LP Supercells

I thought I would make a post about the LP Supercells I chased on July 29th, 2007, just southwest of Alsike, Alberta. So far, they're the best structured storms I've ever seen. As you will see from the noisy quality of the photos, I used a crappy point and shoot digital camera, shot with no composition in mind, shot in terrible lighting conditions and didn't even notice the annoying powerlines in the way! I remember being extremely excited to be seeing these storms up close, so I just pointed and shot away. I've learned a ton about photography since, and wish I had the camera set up that I have now on that day. The models looked pretty good a few days before the 29th for storms to develop in Central Alberta. A nice trough on the west coast, good instability, some moisture, shear and upslope low level flow were present to initiate storms in the foothills. It all came together on the 29th and produced 2 LP Supercells in the foothills west of Drayton Valley, a storm west of Edson and a wicked looking Supercell radar-wise just to the northwest of Whitecourt. I watched radar and satellite loops all afternoon in Red Deer anticipating development and finally towers started to go up late in the afternoon. You could see the top of the Drayton Valley storm all the way from Red Deer! As soon as I seen the tower, I hopped in the truck and drove just over an hour to get to the storm and all I can say was wow.

0z 500mb chart showing the trough in northwestern BC with decent southwesterly flow in Central Alberta.








0z CAPE chart showing up t0 3000 j/kg in Central Alberta.








2200z Carvel scan showing an impressive Supercell west of Drayton Valley, a storm west of Edson and a wicked looking Supercell radar-wise just to the northwest of Whitecourt. I chased the storm that's west of Drayton Valley.





View of the still developing LP Supercell from Hwy 20, looking northwest between Hoadley and Winfield, Alberta. You can see the second LP tower developing behind the main storm.






I obviously got excited when I seen this sight! Crisp anvil, a rock hard updraft, and smoothed base showing signs of rotation. Looking west-north-west south of Breton, Alberta on Hwy 20.






A few kilometers away from the base now which is still organizing tighter at this point. Looking west on Twp Rd 484 just past Range Rd 42.






It doesn't get much better than this. A corkscrew/barberpole updraft spinning away, looking west on Twp Rd 484.






This LP had great mid-level rotation. This vertical shot shows the tilted updraft from stronger winds aloft.










I called EC to report this rotating wall cloud due west from the intersection of Twp Rd 484 and Range Rd 42 which prompted them to say that this storm was capable of producing tornadoes in their severe thunderstorm warning.




The start of a funnel appeared not long after the report I made to EC. After this photo I drove west down Twp Rd 484 for a closer view. You can see the lowering from the second LP in the background.




Funnel spinning away with crepuscular rays poking out of the second LP Supercell.







Funnel reaching nearly halfway to the ground. From my location, I could not confirm a ground circulation.







Dissipating funnel/circulation to the right, with the new LP due west along Twp Rd 484. The funnel only lasted a few minutes.







The still rock hard, but dying updraft from the first amazing LP passing to the north of my location, still on Twp Rd 484. I'm sure precip from the second LP's forward flank must have killed this storm.








Very nice bell shaped lowering ingesting scud curtesy of the second LP Supercell. Back on Hwy 20 now, looking west just south of the Alsike, Alberta gas station.






Beautiful anvil of the second LP passing to my north moving east-north-east along Hwy 39. After the first LP died, I watched the second LP for awhile but called off the chase after it showed signs that it was weakening. Apparently this storm gave Edmonton quite the light show later on!





Charts and radar scan from tornadovideos.net