By Justin Poublon
October 18, 2019 - 10:30 AM CST | 880 0
The rest of October will bring below average temperatures to Wisconsin. There will be warm days sprinkled in but for the most part; we seem to be descending into an early winter pattern.
The jet stream will turn from southwesterly to northwesterly (northwest flow) more commonly starting next week following an early week storm. This tends to pull colder air down from Canada. This is in contrast to the pattern we've seen the last 30 days which features strong low pressure systems coming out of the southwest in southwest flow-western trough dominated regime.
What kind of temperatures? We will flirt with/fall below the freezing more commonly. Again it's normal to dip below freezing at times in Late October. It's really about the frequency and magnitude of the freezing. So really the question is - what will it feel more like? Fall or winter? This year it may feel more like winter. I'm not ready to go with that headline yet.
7-Day Wisconsin Rapids temp graph as an example...
As for precipitation trends, the CPC and model forecasts are near average. This is because as the jet stream takes on a northwest flow configuration, storms become drier and colder. I think the pattern will stay active for Wisconsin. The potential for heavy rain is decreasing. An average precipitation pattern for late October would consist of fast moving systems, rain occasionally, and maybe some snow mixed in. I would plan for that. I know hunters are looking for snow. I wouldn't be surprised to see accumulating snow at some point I just can't yet say whether that will be on time.
The GFS model even suggests lake effect snow pattern developing by the last week of October. Confidence is low at this stage. Forecast models disagree on the strength and magnitude of this pattern going forward. So we will start with this and see where it takes us. Thanks for reading!