All WISCONSINWX.COM posts and stories from January 2018
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Top teleconnection analogs suggest the 2/3 -2/9 timeframe will be cold. 1996 name drop, one of the coldest group of days in recent Wisconsin weather history. There has been agreement on the end of February cold for awhile now. The month overall will be cold.      
Snow passing through this morning. Up to an inch of accumulation possible.
The second craziest thing that's happened this winter.8" of snow in southeast WI is more than most places in the snowstorm up north! Saw it for about 20-30 consecutive runs bouncing around southeast Wisconsin lol. There were many ways this could have been missed. I saw it as minor/small scale wrap around, weird surface low relocation thing. Bigger snows to the north took priority so I pushed this off into it's own separate bucket planning to deal with it but never did. Never thought of it as a 4-9"er. When MKX issued the advisory I thought they were just doing what they always do lol, but it was a great move on their part. Just fell through the cracks.
Plenty of updates, fixes, and changes since Saturday in addition to a northern Wisconsin snowstorm. Going to slow down this week. Always looking ahead towards future storms and projects.
A few thunderstorms in southeast Wisconsin tonight! Small pea sized hail is common with these but severe weather not expected. This cluster will change to snow overnight and may produce a quick burst of 1-3" in the southeast! From tstorms to winter wx advisory. That's pretty cool! -JP
Forecast looking really good right now
Two main precipitation regions splitting west and east of Wisconsin right now. The space between will fill across north-central Wisconsin today as the low moves through. The western region is at the left exit of a diverging upper level jet. It has the strongest forcing, what I would call the true deformation zone, and starting to look pretty good. The right is mostly WAA, accompanied by weak upper divergence and the moist axis. Both areas have strong 850mb WAA. I see this happen often where weak returns are found between two clumps of precip. North-central is in between with dry slot sneaking into the south. You'd have a better chance are reaching forecast snow accums in either the west or east clump. This explains the trends in models this morning.
Strange forecast on the AO today with many taking a nose dive by Feb 1. I don't buy it yet since I do not see it on the models, but -AO of this magitude will certainly lead to cold. Then on the PNA side you have one member totally going negative while the rest trend toward positive. 
Our first snowfall prediction map for the Sun-Mon event. Forecast coming soon. Watching freezing rain potential in central Wisconsin, possibility of locally higher amounts in the 6-12. Rain to the south. Keeping Tues AM wrap-around precip out of for now
WIWX 6.2 launched this afternoon! Don't forget to refresh your browser cache or hit F5 + CTRL to update page appearance if it looks weird. Will try to fix this for next update.
southern trend in most models today following the EC's lead. At the surface most models are pretty close to the EC. The ensembles are leaning in that direction. At 850-700mb I see some things that need to be sorted out. Storm is coming on shore now. GFS CMC storm track is actually from Dubuque to Sheboygan, EC slightly south of that. 
Moisture for the Sun-Mon storm will come from eastern Mexico and western Gulf of Mexico. What I call a "moisture front" arrives just as storm #1 pulls away. The moisture will get buffeted slightly early next week but will be ready for #2 as it crosses the country. The stage is set moisture-wise for some interesting weather late January and Feb. If we can get the AO to slide back positive while holding onto a weakly negative PNA we will be in good shape. Curious to see how things come together in that 6-14 day period. It's been such a boring winter to this point. 
A low pressure system will move through the Great Lakes Sunday 1/21 -> Mon 1/22. Rain, snow, and mixed precipitation is expected with this system. Models have been trending north since the start of this week suggesting more rain for Wisconsin. The storm track will KEEP CHANGING as we get closer, but this is what it's looking like right now.
There are issues with the tag and category pages that will be fixed on the next release. 
Image on the left was the initial forecast from Saturday. Right is from this morning. The southern trend in the last 24 hours was unexpected and the trend continued right through the start of the event. Snow was clumped over the southwest and northeast and not evenly distributed across the rest of Wisconsin. Never make the same mistake twice. I learned a few things. First, broad brushing WI with 3-6" did not work. I could have lowered them in the north. The map in between these (not pictured) was actually pretty close. Second was to post snow maps too early that forces you to bias previous ideas. There will be changes before the next system. 
Just one of those years I guess
60 DAY PRECIPITATION TREND - Snowfall has not been distributed equally across Wisconsin during the first half of winter. This liquid precipitation (including snow melted to water) departure from average map shows northern Wisconsin has come through near average. They are doing alright. Lake effect has helped in upper Michigan. Meanwhile folks in the south are facing a 2.0" deficit. It has been colder than average, which should mean more snow/less precip. The storm track has been out of the northwest bringing dry Canadian clipper systems, efficient but narrow snows. What exposed southern WI/northern IL this winter is the lack of a big storm (snow or rain). We'll see if we can change this trend in the months ahead.
Looking at historical data for Oshkosh. We are at 4.1" snow accum. This is the lowest since the 2014-15 winter which is only a few years back. 2012 had 0.9" through Jan 10. So lack of snow is not uncommon at KOSH. What is uncommon is the combination of below avg temp and below avg snow. On average more cold = more snow. There is one year with this relationship that had same level of snow accum (<=5"). 1925 was much warmer in the second half of winter, precip at average, snow below avg. We don't know much else about 1925. This demonstrates that it is rare to be this cold and not have the snow to go with it. It translates into a boring, cold start to winter but I would be surprised in this trend continued into the second half of the 2017-18 winter. 
SNOW DEPOSITS - 2-6" of snow was deposited onto northwest Wisconsin by the latest storm. 9.3" of heavy snow fell in Gile with help from lake Enhancement. Lesser amounts in central and northeast regions. The freezing rain impact yesterday was very localized. Combo of warm ground temperatures and quick moving front turned out to be unfavorable for ice accumulation. Rapidly falling temperatures left us with icy spots today.
Heavy snow is developing across northwest Wisconsin. Looks like 2-6" of additional snow accumulation, lesser amounts in the northeast. To the south, light freezing rain was reported in northeast Iowa earlier. This precipitation is moving into southern Wisconsin now. Up to 0.10" of ice accumulation is possible this afternoon. And for the icing on the cake, a 50F temperature swing from northwest to southeast Wisconsin! flash freeze seems likely. Precipitation will end tonight.
24HR temp change shows location of cold front across western Wisconsin. Feels great in Oshkosh this morning. 
40F difference in high temps from northwest to southeast Wisconsin tomorrow. Everyone cools off with the cold front passage. 
Here we go, Wisconsin. We are entering a stormy and unsettled pattern. Tendency towards upper level troughiness will return to western north america to the first time this winter. 
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