1:30PM MON - Storm keeps trending south and could miss WI entirely. Pretty crazy shift here in the last 72 hours.
8:50PM SUN - watching 18/00z models come in and they generally support a further south track with heaviest amounts along and south of the WI/IL border. it's a shame really after this looked like a direct hit yesterday. The way this season has been. 18GFS is coldest/furthest north consistent with what it's been showing for a few days. It's an outlier though. Unfortunately consistency from one model doesn't mean much... agreement and consistency between models what we're looking for. Waiting for 00 GFS maybe it will cave. While its not out of the question several inches of snow could still end up in a good portion of southern WI - think we need to go with the broader consensus which is south and back off on overall verbiage. Planning a full update tomorrow morning. -JP
1:26PM SUN - 12EC coming in further south and has been trending south/changing every run. GFS/NAM consistent for southern WI. I did push the accumulations further south. Will wait for evening runs to see if all models support the EC or if its an outlier.
12z EC model snow shifting south. GFS/NAM staying consistent.
7:00AM SUN - GFS appears to be an outlier based on 00/06 guidance. Even the ensembles agree with EC/UK/NAM. The northern trend we saw yesterday seems to be trending back south and now centered on far southern WI and northern IL. Waiting for the 12z. Don't think there is much hope for northern WI atm. Things can still change.
12:00AM SUN - Winter storm possible for southern and perhaps central WI Tuesday into Wednesday. 00GFS/18GFS ensembles tonight definitely the most aggressive bringing a swath of 12-18 inches. I wont go that far. 00EC was weaker and further south so reason to hold off. Below is just a little eye candy showing the 500mb low taking on a negative tilt over Wisconsin. Stay tuned!
500mb trough pivots from neutral to negative over WI.
12:30PM SAT - 12z models trending further north and snowier for Wisconsin. Could become a major storm.
8:50AM SAT - Models this morning a more aggressive developing a winter storm centered on Tuesday across southern WI and perhaps central WI. Could be 5-10 inches with this. Models disagree on location of heaviest snows.
4:00PM FRI - Got sucked into development projects this week. I plan to update this forecast tonight. This storm is targeting southern WI and Illinois based on latest models. -JP
7:00PM WED - no changes to latest forecast. A storm is definitely possible in portions of Wisconsin next week. Will update this forecast on Thursday.
PREVIOUS - Changes going on with the overall weather pattern means this storm could be playing pinball for a few more days. Several times this winter storms have been pushed south in that 150hr+ timeframe because models were overdoing the cold. I suspect models are a little too aggressive this time too and EC/others could come back. 12EC did trend further north but still south of WI. GFS was most aggressive with major storm, EC and the rest were forgettable. The GFS ensembles show many stormy scenarios(pretty much typical). Confidence is low for this forecast hour given the uncertainty of the bigger picture. Timing also subject to change.