June 13-30 Severe weather

[Quincy]

The 5% tornado threat area did not produce anything tornadic, but I was able to witness this supercell in north-central Kansas, in Courtland, last night:

[MNstorms]

Decided to extend that title date since rounds of storms continue. 

Nice bow echo coming at me tomorrow at noon perhaps. 

 

[MNstorms]

Current storms:

Models want a tornado outbreak this afternoon. SPC isn't saying anything. Atmosphere will be used up I assume. 

[MNstorms]

10% in ND with a larger 5%. Tomorrow has a slight risk now too.

 

 

[Chinook]

That is some tremendous CAPE. It's always cool to see some numbers like that. What's more rare is to have a significant amount of shear in late June or July.

[DanLarsen34]

This is an all-timer sounding. This is the Aberdeen sounding from a little while ago. 

[Quincy]

That ABR sounding looks insane with the severe weather parameters, but what stands out to me is relatively weak/sub-marginal winds in the mid to upper levels. Particularly 700-500mb, where winds are <30 knots.

The 00z BIS sounding is arguably more impressive, but it's in close proximity to the cold front. It showed a large capping inversion, but even stronger deep layer year.

Another thing to note is that >30 knot deep layer shear is not uncommon at all in the Northern Plains in late June. In fact, sounding climatology suggests that mean 0-6km shear for 00z 6/30 at ABR is 35 knots and 38 knots at BIS. One of my favorite times of year and places to storm chase would be the Dakotas in early to mid-summer.

The ABR low-level lapse rates are not bad, but near-term point forecast soundings for the enhanced risk zone in central/eastern North Dakota show relatively weak 0-3km lapse rates of near or <6 C/km. It looks like there was no sustained convection in the area until just the past hour when a storm initiated near Jamestown, ND. Even that storm is struggling at this point.

One of the issues with the Northern Plains this time of the year is that cap busts are fairly common. All you need is extreme instability to juxtapose with marginal/modest shear to see severe weather parameters go off the charts.

[Amped]

LP Tornadic cells are the best.