CLIPPER'S GONNA CLIP
First, let me say thank you for all the spectacular birthday wishes. When I was a kid, if I knew the amount of emails, texts, Facebook messages, and phone calls I would receive, I literally would have been bouncing off the wall. How nice it is to know so many of you would take the time to send a message. I'm moved and overwhelmed, you all made my day very special.
One of the odd aspects of my birthday is that I love snow. The more, the merrier. Up until yesterday, I hadn't seen more than a dusting all year. I was a bit despondent about that. So, I go to Madison with my wife and daughter to spend some quality time. What do you think happens? It snows 2 inches at my place in Dubuque and I miss it. What in the name of Sam Hill! Anyway, what fell was still here when I got home and I did get to shovel it, but I get my real jollies sitting by the fire watching it fall. If it ain't one thing, it's another. If nothing else, it finally looks like Christmas....frosting on my birthday cake.
CLIPPER IN-COMING
By the way, Tuesday night's snow was a rather unique event that was narrow but intense. Frontogenesis at 700mb combined with ideal temperatures and a 120kt jet streak, created the snow band in my northern counties. 1-2" of snow fell in a short time, creating some very slick traveling conditions. Here's the NWS reports.
Another perspective showing the localized 1–2 amounts clustered around Dubuque.
Another system, far better organized, will bring a beautiful snow to the upper Midwest Thursday. The clipper has all the trappings for a healthy snow event that brings a solid 3-6 inch snow to Minnesota and much of Wisconsin. Some local 8" amounts are quite likely where forcing is maximized. Sadly, for those of you looking for snow at Christmas around here, the track will be just far enough north to preclude any accumulations in my area aside from the far north. Even there, a small shift north would pretty much make it a nothingburger. Winter storm warnings and advisories have been posted further north for Thursday.
If you will be traveling north with the holiday approaching, be advised conditions will be slow-going Thursday. Here is the snowfall forecast for the southern half of Minnesota and SW Wisconsin.
The problem restricting snow in my area is the forcing and lift for snow will be minimal south of the clipper and its warm air advection. The surface low on the EURO tracks E/SE towards Dubuque on the EURO.
Such a scenario keeps conditions essentially dry for all but my northern counties, and even there (as previously mentioned) a small shift north could make precipitation nothing more than flurries. On the other hand, a shift further south increases snow prospects in my far N/NE counties. I think that's unlikely. Here's what models are suggesting for snow totals. Keep in mind, this is just the raw data that the official forecast (to follow below) is made from. For now, if you are south of HWY 30, especially south of I-80, you are out of the snow game.
The EURO
The GFS
The 12k NAM
The 3k NAM
The 10K GEM
The HRRR
In summation, the deterministic runs of the EURO and GFS don't show much for snow south of HWY 30, if any. On the other hand, the hi-resolution models such as the 3K NAM, 12K NAM, and 10K GEM are more generous and further south with accumulations. (The HRRR, not so much). Personally, I don't expect much snow south of HWY 20. The big snow winners will be found in Minnesota and Wisconsin. I tip my hat to them.
The official NWS forecast locally looks like this. Note the range from a trace to 2 inches in Dubuque. The 2-inch variance indicates low confidence in potential amounts across my northern tier of counties.
The NWS model also shows these odds of an inch or more of snow.
After the clipper passes, much of the coming weekend looks cold and quiet, with highs confined to the 20s.
There is one other crack at precipitation/snow before Christmas, and that comes on the 23rd. Thermal profiles are in question as well as the amount of forcing, so this event is still in the early stages. Additionally, the latest trends have come in drier and weaker. Whatever happens, precipitation is not expected to be heavy or impactful. Plenty of time to dial in on this system.
With that, I will call it a post and watch as we get clipped by another clipper. Close but no cigar. Have a sensational day and roll weather...TS
