Well models are starting to agree on the idea that a significant weather event will take place Tuesday late afternoon/early evening along the Alberta/Saskatchewan border...more specifically...the Lloydminster area.
Surface to H50 wind directions are looking really good along with the speeds (Bulk Shear ~55kts). Moisture looks great with a southeasterly H85 jet advecting in 12-15 degree dewpoints at that height. At the surface it looks like dewpoints in the 15-20 degree range shouldn't be hard to reach either as moisture is advected in from the southeast. We also can't forget the effects of evapotranspiration which is in full swing at this time of the year.
CAPE values look pro AOA 3000 j/kg if you believe the 00z NAM...anyways...I can go on about the positioning of the thermal ridges at specific heights and where they're forecast to lie...but to keep things short and sweet I'll end with saying that the trigger looks to lie around the edge of the ridge as upper level cooling comes in from the West along some sort of coolish front lifting NE from the Elbow region of Alberta earlier in the day.
Here is a sounding/hodo for the YLL area Tuesday evening..impressive!
The tornado threat is actually quite high with this set-up along with the threat of large hail and strong winds. Storms will likely fire North of Lloyd where capping is removed first and then develop further South into the more unstable air.
Storms look to persist through the evening/overnight as they truck eastward as a giant squall line with damaging winds.
Model consistency is improving showing the Lloyd area...but the previous run showed Elrose, SK as the hot spot...so that's not that far off in terms of highlighting a threat area for Tuesday...but I'd put money on the fact that there'll be tornado warnings issued on Tuesday if this 00z run verifies!
GFS is somewhat in agreement with the NAM I see. Tuesday could be a very interesting day in the western prairies if things play out as model land forecasts them.
ReplyDeleteThe big if is the moisture. Will dews make it up that far north, and will they mix out if they do?
ReplyDeleteI'm concerned about this because it happened to us in Nebraska a while ago.
And by the way, evapotranspiration isn't as much of a factor this year, because of all the flooding around the prairies. So it might not be evapotranspiration as evaporation. :P
I do agree, though, that regardless, if I had the chance I would be out chasing this setup. Often times dynamic effects can overtake moisture deficiencies.
But unfortunately I have to be in Edmonton that day. Justin, will you chase? I know we had planned to meet for a drink but if you want and are able to chase this setup, I wouldn't begrudge you chasing this setup and we can meet for drinks another time.
good god . . . i'd love to go chase this set up. A mere 4 hour drive away. Definately.
ReplyDeleteIf I didn't work tuesday night.
It certainly will be an interesting beginning to that night shift though.
Based on a so so analysis. I'd probably go somewhere around Unity or Cutknife, SK. West of North Battleford.