Storm update: Period of rain/ice may lower metro snowfall totals

Mixed Saturday Precipitation Should Still End As Plowable Snow

Paul Douglas
March 08, 2019 - 11:51 am
Big Piles of Snow

Paul Douglas

Categories: 

A significant storm is still on track to affect most of Minnesota and a big chunk of western Wisconsin Saturday into Sunday morning. For most of central and northern Minnesota there's little question precipitation will fall as all-snow.

But from the Twin Cities on south/east there's a growing chance of a period of rain and ice (freezing rain) Saturday afternoon as temperatures aloft rise above 32F. Recent model runs have increased the possibility of a sloppy winter mix, especially far southern Minnesota, but Minneapolis/St. Paul may also experience a few hours of rain and/or rain freezing on contact with cold surfaces Saturday afternoon. With temperatures in the metro forecast to be close to 32F I expect most freeways to be wet/slushy during the afternoon hours tomorrow, but watch bridge overpasses and secondary roads, especially outside the immediate metro.

- Rain/ice/snow mix possible from the Twin Cities southward to the Iowa border Saturday afternoon, changing back to all snow Saturday night; thinking closer to a Sunday total of 4-8" of very wet/slushy snow for the immediate MSP metro (less due to mix of rain and ice Saturday afternoon).

- North and west of MSP precipitation should fall as mainly snow, with a better chance of 8-12" from Willmar and Alexandria to Wadena, Brainerd and St. Cloud.

- Travel probably not recommended across most of the state, especially Saturday afternoon and night. I expect conditions to slowly improve during the day Sunday.

Serious Snow
Pietro Zanarini

Note to Readers: We Will Not See This Much Snow. I've heard some crazy rumors out there - this will probably still be plowable for the MSP metro, but with a growing possibility of a wintry mix Saturday afternoon I'm cooling on the upper-end snowfall predictions of 12 or 15". It could still happen, but the odds of a foot or more for the immediate metro have diminished a bit since yesterday.

Winter Storm Warning
Praedictix and AerisWeather

Winter Storm Warning. Which means it's pretty much inevitable and imminent. The warning is in effect Saturday into Sunday morning. The worst travel conditions should come Saturday afternoon and night, when a combination of heavy snow (and ice), high winds and low visibility will make for treacherous conditions.

Ice Potential
NOAA and pivotalweather.com

Icy Possibilities. The map above is from the 12z 3KM NAM-WRF model, which has had some issues as of late, but I don't want to totally ignore the trends, either. The latest NAM model from NOAA brings a surge of milder air (warmer than 32F) about 4,000 to 7,000 feet above the ground Saturday afternoon, which could mean a few hours of rain or freezing rain (rain freezing on contact with cold surfaces). The NAM isn't gospel (there is no perfect model) but it may be picking up on a trend of milder air pushing farther north. The implications include: potentially less overall snow for the immediate Twin Cities, thanks to a mixed bag of wintry precipitation. I suspect MSP will still see a plowable snowfall of at least 4-5", but I'm cooling on the possibility of 12" or 15", at least in the immediate Minneapolis-St. Paul area.

NOAA GFS Model
NOAA and pivotalweather.com

GFS Model. NOAA's Global Forecast System model still prints out a healthy 6-8" for the Twin Cities, with closer to 10" from St. Cloud and Alexandria to Windom and Marshall - still a very respectable snowstorm for early March (or any month for that matter).

Timing the storm...

Timing The Storm
Twin Cities National Weather Service

Timing Is Everything. Mixed precipitation (snow, rain and freezing rain) may not start up until midday tomorrow in the Twin Cities, but parts of southwestern Minnesota will wake up to a slushy, sloppy mix. In general, travel conditions deterioriate as the day goes on tomorrow. Get your errands done early, if possible.

Future Radar
Praedictix and AerisWeather

Future Radar
Praedictix and AerisWeather

Future Radar
Praedictix and AerisWeather

Timing the Storm. Mixed precipitation is possible in the MSP metro by midday, with the brunt of the snow/ice comine late afternoon and evening hours Saturday.

European Model for Twin Cities
WeatherBell

Just What the Weather Doctor Ordered. ECMWF (European) guidance shows daytime highs fairly consistently above 32F the next 2 weeks, with nighttime lows in the teens, which will act as a brake on snow melt. The longer and slower we can drag out an inevitable thaw, the lower the odds of serious river flooding in a few weeks. Fingers crossed.

So, we have a new wrinkle in the Saturday forecast, with a (growing) chance of rain and ice from the MSP metro into southern Minnesota. That may keep snow totals down a bit, but this is still going to be a major, kick-butt storm. Travel is still going to be a sloppy, slushy mess Saturday afternoon and Saturday night.

One thing is certain: we'll keep you up to date, around the clock, on News-Talk 830 WCCO. I hope you'll tune in this afternoon from 3-6 pm to hear the latest.

- Paul Douglas

 

AP Editorial Categories: