Changes made with this update:
While no major changes have been made, we have attempted to better identify the potential for specific types of impacts in some of the major metropolitan areas as well as to update the areas of uncertainty that continue to exist with regard to the forecast at this time. This is normal for a longer range outlook such as this one, and details will become more clear as each day passes.
Summary:
We are continuing to monitor the potential for a significant winter weather event for much of the Midwest and Great Lakes region primarily for the period Tuesday into Wednesday of next week.
Present indications continue to suggest that potentially significant accumulations of ice, a wintry mix and/or snow are possible – generally within the areas indicated on the above image during the aforementioned time period. Some of these potentially significant impacts may occur within or near the following larger metropolitan areas:
-Twin Cities (mostly snow; highest accumulation may be to the South and East of the city)
-Chicago (ice and/or a wintry mix possibly changing to snow)
-Detroit (ice and/or a wintry mix possibly changing to lighter snow)
-Kansas City (a wintry mix and/or ice changing to snow)
-Omaha (mostly snow)
-Des Moines (mostly snow)
Potential Impacts:
We continue to be in the preliminary stages of monitoring this developing weather event. Present indications continue to suggest that the following impacts are possible in at least some portions of the outlined areas on the map at the top of this image:
-Heavy snowfall (in “Snow” area only)
-Blowing and drifting snow (in “Snow” area only)
-Blizzard conditions (in “Snow” area only)
-Significant ice accumulations (mainly in “Ice” area)
-Scattered power outages (possible in all areas, but especially in “ice” area)
-Scattered downing of trees, tree limbs and power lines (possible in all areas, but especially in “ice” area)
-Scattered structural damage in the form of roof collapse (in “Snow” area only)
-Scattered damage to shingled roofs (mainly in “Snow” area where winds will be highest)
We will assign more specific impact threat levels by area in later updates as the situation becomes more clear. The primary purpose of this alert is to continue to make you aware that a significant winter storm is possible in the indicated areas during the general timeframe described above.
Primary Areas of Uncertainty:
In general/region-wide: The exact timing and amounts of precipitation continue to be the primary areas of uncertainty with the forecast at this time, but this will be clarified over the course of the next few days.
Twin Cities Area: Present indications suggest that the heaviest snow axis may pass just to the South and East of the Twin Cities area, closer to the Iowa and Wisconsin border. This is a continued signal since yesterday, which is gradually increasing our confidence in that scenario. This is not to say that significant snowfall will not occur in the Twin Cities, but that the heaviest snow appears more likely to be to the East and Southeast of the area itself. This could change, and we will continue to monitor trends.
Chicago Area: We are beginning to see signals that suggest precipitation may be in the form of ice (freezing rain) and/or a mix of freezing rain and sleet for a longer time period on Tuesday and then again on Tuesday night, before changing to mostly snow on Wednesday morning. If this occurs, then the potential for ice accumulation would generally increase across at least parts of the Chicago area, possibly becoming more of a significant concern vs. impacts from snow accumulation. A considerable amount of uncertainty still remains at this time, and we will continue to monitor the situation