Update Feb 20, 2013:

A major winter storm is set to hit the Central Plains tonight and Thursday. A foot of snow is possible with strong winds across a handful of states. Just a few inches of snow is likely Friday in West Michigan.

If you scroll all the way down to my original post, you’ll see the Euro was way off on Michigan snow, but did a great job predicting heavy snow for the Central Plains with a full week’s notice.

Winter storm warnings are posted for all of Kansas, most of Nebraska, Missouri, and Iowa.

The HPC’s forecast for more than 8″ of snow.

Update Feb 17, 2013:

This storm still looks like it will be a monster–for the Central Plains, not the Great Lakes. The low itself is now just south of Anchorage, Ala. Forecast models show very heavy snow and a possible blizzard for the Central Plains states Thursday, but that low is now forecast to occlude by Friday and the time it hits the Western Great Lakes. Occluded lows weaken rapidly as cold air wraps around them. Several inches of snow looks likely for West Michigan on Friday because of this storm. We’ll be shoveling.

Original posting Feb. 14, 2013:

It’s not like I’m outing Santa Claus here: We all know that weather forecasting is sometimes less reliable after three and especially five days. But in recent years Storm Team 8 and other forecasters have had some pretty big wins. I mentioned Hurricane Sandy (then a tropical disturbance west of Aruba) as a possible New England hurricane on-air more than a week before it struck, and I’m proud to be part of a team that forecast the second-biggest snow event in Grand Rapids weather history, the Groundhog’s Day Blizzard of 2011 more than a week before it shut down Kent County for a full day. As technology and our understanding of atmospheric processes improves, that window of reliable forecasts is getting bigger.

Here’s how all of that ties into our current weather picture: right now, there’s a noteworthy low in the North Pacific straddling the International Dateline.

The low is over the International Date Line, about 4,800 miles away from Grand Rapids. This is roughly the point where we detected the low that became the Groundhog’s Day Blizzard of 2011.

Wednesday and Thursday there was significant consensus among computer models on the low’s future track and timing, which is remarkable since this storm is still a week away. The FIM/GFS and ECMWF models all show a strong cyclone continuing along the west coast of the United States, crossing the Rocky Mountains and quickly ejecting into the plains. Wind fields are strong, and the Gulf of Mexico moisture channel is open.

The storm track will be somewhere in the western or southern Great Lakes, or Ohio Valley. Considering the distance this storm has yet to travel, I consider that a small target. The European has the best recent record and is calling for a low to track from Indianapolis to Newark. That keeps West Michigan in the all-snow sector and gives us very strong winds.

Accumulated snow for the coming week from the Euro model. Most of this snow falls on Friday, Feb. 22, about one foot of snow. (weatherbell.com) This is not the Storm Team 8 forecast.

The GFS tracks the low just north of Grand Rapids, which means we’ll see some rain in this system at first. That will cut back the snow totals significantly, but we’ll still get snow, cold and wind on the back side of this low.

Either way, with this mostly feeble winter, this storm could be the single biggest snow producer we see for the season, and certainly it will be worthy of staying in touch with us as next week unfolds.

Biggest single-day snowfalls in Grand Rapids this season:
1) 5.9″ on Feb. 2
2) 5.2″ on Feb. 7
3) 4.6″ on Jan. 31
4) 3.2″ on Jan. 23
5) 3.1″ on Jan. 21 and Dec. 26

Also noteworthy: Many school districts are on a winter break late next week, meaning no snow days