nvck Posted Friday at 01:28 PM Share Posted Friday at 01:28 PM Figure it's probably time to start a thread for what looks to be a 2-day severe weather event across the region. CSU (per usual) is pretty aggressive with it's probabilities, but is outlining much of the same area as the SPC has. It's looking like all severe modes are possible on both Monday and Tuesday, and Tuesday has been uptrending over the past couple days, so I'd expect higher probs coming from the SPC. 1 Link to comment Share on other sites More sharing options...
sbnwx85 Posted Friday at 05:52 PM Share Posted Friday at 05:52 PM I'm worried I'll get stuck between the two risks. Maybe I can get initiation to occur overhead on Tuesday. The GFS is more hopeful than the Euro at last check. 1 Link to comment Share on other sites More sharing options...
CheeselandSkies Posted Friday at 07:43 PM Share Posted Friday at 07:43 PM As of this past Monday the signal was strong enough for me to book PTO for this coming Monday-Wednesday so that I can chase Sunday-Monday and perhaps Tuesday. Based on modeling over the last few days, currently will probably target somewhere along the central to western KS/NE border on Sunday and north-central to northeast Iowa for Monday, although tornado parameters look potentially dangerous into Wisconsin. 4 Link to comment Share on other sites More sharing options...
yoda Posted yesterday at 07:48 AM Share Posted yesterday at 07:48 AM Oh... okay then Link to comment Share on other sites More sharing options...
A-L-E-K Posted yesterday at 11:41 AM Share Posted yesterday at 11:41 AM Jelly 1 1 Link to comment Share on other sites More sharing options...
nvck Posted yesterday at 02:04 PM Author Share Posted yesterday at 02:04 PM I think the decision to pull the trigger on a day3 MDT was at least partially supported by Broyles et al. findings in the OMEGA project, which found that jet streak translation speeds >40kt are associated with higher-end tornado events. Doing some rough math, from the 6z NAM, it looks like at 6z monday the core of the 500mb jet is over eastern NM, and by 6z Tuesday it's not as obvious where the core of the jet is, but it appears to be somewhere around the northern shore of Lake Superior. This would suggest a translation speed of around 49kts, well above the threshold mentioned in the paper. The SPC also mentions the jet translation speed in the outlook: A strong mid-level jet streak will move rapidly northeastward from the Southwest to the Upper Midwest on Monday. I could be wrong, but this is my best guess as to why they went moderate today instead of pulling the trigger tomorrow Here's the paper if you're interested: https://prod-west-spc.woc.noaa.gov/publications/broyles/omega.pdf 5 Link to comment Share on other sites More sharing options...
CheeselandSkies Posted yesterday at 03:42 PM Share Posted yesterday at 03:42 PM Copy/paste of what I just posted on TW: There are some weird things about this setup. It's certainly not going to be your absolutely classic 500mb pattern for a tornado outbreak (like, say 3/31/23 and 4/26/24 were). At first glance the 500mb looks way too positively tilted. However, it doesn't seem to have the big problem you usually get with a strong positive tilt, which is a SW-NE oriented front with all the strong 500mb flow parallel to and relegated to largely along/behind it. With Monday, at the surface we still have a more N-S oriented cold front/dryline with the flow extending out over the warm sector. NAM/3K NAM are also doing weird things with the thermos (surprise) which makes it tough to get a good handle on what the warm sector environment will actually be like over Iowa/Wisconsin going into Monday evening. All in all I think the Day 3 MDT was a bold call given all this (seems to be based solely on the jet translation speed), but they're the ones who have been doing the work on it. 1 Link to comment Share on other sites More sharing options...
mnchaserguy Posted yesterday at 05:05 PM Share Posted yesterday at 05:05 PM I haven’t been a believer because something has just seemed off. Probably mostly the lack of better heating and narrow cape ribbons. However the RAP is screaming outbreak. If it’s correct or even somewhat close then we could be in real trouble. This is the RAP at 21z in western MN on Monday. . Link to comment Share on other sites More sharing options...
CheeselandSkies Posted yesterday at 05:29 PM Share Posted yesterday at 05:29 PM 23 minutes ago, mnchaserguy said: I haven’t been a believer because something has just seemed off. Probably mostly the lack of better heating and narrow cape ribbons. However the RAP is screaming outbreak. If it’s correct or even somewhat close then we could be in real trouble. This is the RAP at 21z in western MN on Monday. . Where'd you get that? Furthest range RAP run I know of right now is today's 15Z which goes out 51 hours to 18Z Monday. Link to comment Share on other sites More sharing options...
mnchaserguy Posted yesterday at 06:01 PM Share Posted yesterday at 06:01 PM Where'd you get that? Furthest range RAP run I know of right now is today's 15Z which goes out 51 hours to 18Z Monday.Whoops. Mislabeled. It is 18z on Monday. . 1 Link to comment Share on other sites More sharing options...
cyclone77 Posted yesterday at 07:45 PM Share Posted yesterday at 07:45 PM Poor timing for the most of the DVN cwa with this. Link to comment Share on other sites More sharing options...
mnchaserguy Posted yesterday at 08:14 PM Share Posted yesterday at 08:14 PM 18z hrrr is similar at 18z on Monday to what the 15z RAP showed. May get some waa storms here in MSP and north towards Duluth in the morning. Could be some hail with those. If we can actual get that clearing after the waa convection we should be in business. . Link to comment Share on other sites More sharing options...
mnchaserguy Posted 20 hours ago Share Posted 20 hours ago This is the 21z RAP sounding over my house at 23z on Monday. . Link to comment Share on other sites More sharing options...
Chinook Posted 19 hours ago Share Posted 19 hours ago GFS has these dew points, with a very unstable/uncapped atmosphere near Des Moines. This is Monday afternoon/evening. Strong 850mb-500mb winds, low LCL values favorable for tornadoes. Effectively, a dryline will get up into Iowa in the 00z time frame. Link to comment Share on other sites More sharing options...
hawkeye_wx Posted 9 hours ago Share Posted 9 hours ago Despite the warm, moist air surging north into Iowa, most models show little, if any, storm activity around here. Are we capped or something? Link to comment Share on other sites More sharing options...
CheeselandSkies Posted 7 hours ago Share Posted 7 hours ago Not sure if I've ever seen SPC go so hard against the CAMs before. Used to those models being overly bullish with supercells that don't happen (such as the meme-worthy HRRR run from the morning of 5/20/2019). Link to comment Share on other sites More sharing options...
nwohweather Posted 5 hours ago Share Posted 5 hours ago 4 hours ago, hawkeye_wx said: Despite the warm, moist air surging north into Iowa, most models show little, if any, storm activity around here. Are we capped or something? Yes. The Euro shows it breaking and their riding it is my guess Link to comment Share on other sites More sharing options...
mnchaserguy Posted 4 hours ago Share Posted 4 hours ago 9z rap sig tor is maxed out over MSP tomorrow. Never seen it this high here before and may never see it again. . 1 Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now