WEDS 7:30AM - wind gusts will increase into 30-45 MPH range as the surface low pulls away.
TUES 12:30PM - Updated maps and wrote official forecast (see blog post below). Waiting to do a live video stream this afternoon and will use that to finish out this event forecast. -JP
MON 6:20PM - Just wanted to demonstrate the higher end snow total potential in this FB post.
MON 1:20 PM - No changes to previous forecast based on 12z run. I strongly considered pushing the 4-8" to a 5-10", but looking at 12Z NAM showing some weakness across northern Wisconsin for snow amounts. I feel better about 4-8" still. Tomorrow morning I will reassess everything again and issue the final forecast. I highlighted Minneapolis as one place that could see those locally higher 8"+ amounts. Also highlighting the Marquette MI area.
MON 9:00AM - A northward shift and slightly stronger storm since the last update resulted a in pretty large shift north of the snow band. This was kind of expected. Moving forward with "Major Storm" verbiage; between wind and snow and Thanksgiving travel I think it's the best strategy. This brings the last 7 days of forecasts together. Crazy how this storm is backing into what I initially laid out last Monday after several days of whatever. Confidence level remains average... I will feel better on Tuesday when short range models arrive.
Wisconsin Weather
HEAVY SNOW - I considered a 5-9" zone for northwest Wisconsin. NAM high res is at the edge of it's forecast period and gave me reason to hold back. I feel more comfortable with 4-8", locally higher amounts. This puts us in a great position to add detail of short range models on Tuesday and avoid shooting in the dark today. Normally with a major system you could nail down the narrow heavy snow band. But this one is a little different; models haven't always been coincident with heavy snow features which leads to a wider band. Thus 4-8". In conclusion; I know 8"+ amounts will occur. Just a matter of where. One place is upper Michigan towards Ashland where the combination of better snow ratios and lake effect could push totals towards 12".
The 0-1" zone; probably won't see snow until mid-day Wednesday. Not much faith in accumulation there.
WINDY WEDNESDAY- Wednesday into Wednesday night will be the windiest timeframe. Like the last system, because the low pressure track is directly through Wisconsin the winds will be weak on Tuesday PM. However wind gusts will increase on the southern and northern fringes first, then surge out of the west as the storm pulls away. I'm forecasting the highest wind gusts along lake Michigan in eastern Wisconsin, down along and south of the WI/IL border. 40-50 MPH. I also pulled it through upper Michigan...though it might be more like 35-45 MPH there (away from the lake). For the rest of Wisconsin I like the 30-40 MPH range; especially with the aforementioned weakness due to low pressure center passage. See map below.
EC model wind forecast for Wednesday morning. Wisconsin in a hole relative to other places, but wind gusts will increase during the day Wednesday after the surface low passes.
HEAVY RAIN - On yesterday's update I had little faith for heavy rain. I still won't go crazy with it; expect the dry slot to power through. Today I feel that with the northern shift and slightly stronger system; we can pull the 0.5-1.0" into eastern Wisconsin quite confidently. Not a big story outside of places like Door County, far east-central Wisconsin where we could see 1.0" amounts.
Next update this afternoon after 12z models along with the official blog post/story.