1. 2. 3. Northern Wisconsin Weather: Snow across northern WI, severe storms in the Deep South. 4. 12. 15. 16. 17. 18. 19. 20. 23. 24.

25. 26. Snow across northern WI, severe storms in the Deep South. 27. 28.

The snow wasn't quite as heavy as first predicted.

Winter Weather Advisories were issued for most of Wisconsin Tuesday and Tuesday night by the NWS Offices covering the state (Dlh, Mpx, Grb, Mkx, & Arx).

I posted a map (previous blog post) of the forecast snow totals across Wisconsin.
This radar loop (to the right) was compiled by OSNW3 and shows the precipitation as it moved across the region.

Reported snow totals.

I won't spend more time than I already have searching for reports, but I did manage to compile some snow totals on a map (to the left).

I added two contour lines -- greater than two inches in green and greater than five inches in peach(ish) [honestly, I'm not sure what to call it... Atomic Tangerine comes close or maybe Gamboge].

NWS Green Bay had forecast between 4 and 7 inches for their area... which seems to have been accurate for nine out of nineteen counties (9/19=47%).

NWS Duluth's forecast was between 2 and 5 inches for their Wisconsin counties, which was correct for six of their eight counties (6/8=75%), and was actually under-predicted for two counties (Bayfield and Douglas).

NWS Minneapolis had forecast 1 to 3 inches for their nine Wisconsin counties, these counties saw anywhere from 1.9 to 4.5 inches... not bad.

NWS La Crosse saw four of their thirteen (4/13=30%) Wisconsin counties report more than 1 inch when they originally forecast 2 to 5 inches for their area... quite a bust.

And speaking of busts, NWS Milwaukee seems to have missed their mark completely. I found only one snow report greater than 1 inch on the local storm report (LSR) list, from Fond du Lac county. Their original forecast was 3 to 5 inches across the northern-half of their area with lesser amounts south. Zero counties reached their forecast snow totals from their 20-county area.

Something cool on radar.

For a couple hours there was a feature which OSNW3 and I have discussed in the past, except reversed.
I'll call it a 'reversed' Bayfield Bomber.

Occasionally, when the winds are from the southwest and lake-effect snow occurs, a very heavy streamer is formed by the topography of Bayfield Peninsula which brings very heavy lake-effect snow to the UP of Michigan.

In this case, the wind was from the opposite direction and brought a heavy lake-effect streamer into Bayfield, Douglas, Burnett, and Washburn counties. It was under this heavy band that 6.5 and 5.2 inches were reported from northwestern Bayfield County. This radar image (above) is from 9:01 on the 18th.

The system brought severe weather into the Deep South.

This map (to the left) comes from the Storm Prediction Center (SPC) and displays all the severe weather reports from yesterday (Wed. 18th).

I bring this up because one of my weather-blog friends was storm chasing in one storm and provided a great video. I believe he also provided a great lesson of what you don't want to do.

There were 6 reports of possible tornadoes in five separate locations with no injuries listed. Also reported were 117 hail reports and 42 wind damage reports.

Mike's cell.

Mike hit the road in the morning towards west-central Alabama, after the SPC posted a Moderate severe weather risk covering a large section of Alabama and Mississippi.

I borrowed two radar images from Dewdrop's blog (The Flight of a South Georgia Storm Chaser) where she posted GR images of Mike's cell (to the right).

The top image seems to be Composite Reflectivity of the cell in Hale County, Alabama at 17:24 yesterday (Wed. 18th).

The bottom image is Relative Storm Velocity from the same time, where the cell is beginning to show some rotation.

The radar site (KBMX in Birmingham, AL) is located 60 miles to the NE of this location, so towards the upper right corner of the radar image.

The green colors indicate winds blowing towards the radar site while red colors indicate winds blowing away from the radar site. When you get winds blowing in opposite directions next to each other, it is indicative of rotation in the cell.

Mike's cell started off as a hail threat, but then a Tornado Warning was issued for the possibility of a developing tornado. The rotation seen in the cell was something that could quickly develop into a larger problem.

So, onto Mike's video.

It looks like Mike was not in the best location to be chasing this storm cell. There was large hail and damaging winds as he was driving, even a possibility that Mike was in the middle of a broad and extremely weak tornado. There could have been a tornado behind any tree or wrapped in rain... he was lucky that it wasn't more serious!!!

Mike has numerous postings from his chase on his blog: Alabama Weather
And Dewdrop always has great stuff on her blog: Flight of S.GA. Storm Chaser

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