AM rush hour snow shot; Ice favors SE MN & I-90 corridor

AM Snow Burst looks more likely: (Updated 12:05 am)

Things are looking better now for the (too?) long anticiapted shot of heavy snow centered on Thursday AM rush hour. The upper low is finally making progress tonight, and snow is increasing in coverage and intensity.

The bust potential looked higher for a while Wednesday evening, but now the system appears on track for a shot of heavy snow between 3am and 10am in the metro.

Sticking with 6″ to 12″ overall storm total by Friday across much of central and southern MN including the metro. Thundersnow still a possibility as we move through Thursday morning.

440 wxs3.png

Expect a nasty, snowy AM rush hour and plan accordingly.

PH

Main Event? (Updated 7:30pm for possible bust potential)

***As we move into Wednesday evening, I am a little concerned (hopeful??) about what appears to be a growing “bust potential” for this storm. Radar and satellite trends do not reflect well with what the models have been indicating will happen tonight. If these trends continue, we could see a reduction in expected snowfall totals.

An inflow of milder and drier air from the northeast has cut into support for developing snow tonight.

We’ll have to see if a decent precip shield can develop in southern Minnesota in the overnight hours. At this point, that has come into question.

There is still impressive moisture working north near Omaha into northwest Iowa, so I’ll stick with the going forecast of heavy snow bracketing AM rush hour for now. Just keeping an eye on developing trends. ***

440 radd.gif

***Original post 3:45pm***

So far…so good. Or not so good depending on your outlook.

Waves #1 & #2 of our multi part storm delivered as expected.

Now if wave #3 comes in overnight as forecast, we can praise the forecast models for a job well done. That might be a bigger if than it was 24 hours ago. There is some developing bust potential with this system.

Weather fingers crossed.

It still looks like tonight’s main event will feature heavy wet snow for most of central and southern Minnesota. Worthington is cleaning up from a good old fashioned ice storm now, and Rochester and Winona will likely be doing the same Thursday.

In this Updraft we put the finishing touches on the forecast main event.

All eyes glued to the doppler.

440 wxs1.PNG

Wave #3:

The 3rd and final wave of our April winter storm rolls through tonight.

This part of the storm features the surface low deepening and sliding through northern Iowa.

440 low sfc2.PNG

Image: Twin Cities NWS

Some drier air (dew points in the 20s) is feeding into the metro from the north. Initially this will hold precip at bay, but later cause “evaporational cooling” that will help mixed precip quickly change to all snow as heavier precip moves in tonight.

The quetion is…will the dry and milder air to the north effectively weaken the system more than forecast modles show?

As the upper low…the upper air support part of the storm draws closer tonight. That should provide additional lift and cause radars to brighten with color overnight. Look for precip to increase coverage from the southwest this evening, then spread north and intensify overnight.

Twin Cities NWS has a nice web briefing on the incoming system here.

Overnight Dumping:

So called “dynamic forcing” will likely change precip to all snow tonight. In the metro this should occur between 10pm and midnight as the heavier precip moves in.

It still looks like the period of heaviest snowfall should occur between about midnight and 10 am Thursday. Snow intensity will taper Thursday…but lighter snow should linger most of the day and even into Friday.

Plan on a snowy commute Thursday morning.

440 otg1.jpg

Southeast Minnesota Ice Storm:

For Rochester and Winona, it will be ice.

Last night’s ice storm caused considerable damage in Worthington and south central Minnesota. MPR’s Mark Steil captured the damage today in Worthington.

440 otg2.jpg

Tonight, an overnight coating of up to .50″ ice or more may snap trees and power lines in southeast Minnesota. Keep the wood stove stocked up and handy tonight and Thursday.

440 lse.png

Bottom Line: How much?

Though I have some concerns about bust poterntial, the overall forecast for the storm remains on track. A wide area should see overall storm total snowfall accumulations of 6″ to 12″ by Thursday evening. The one thing that concerns me a little is the lack of cold air feeding into the system. There is some bust potential here.

440 nam snow.PNG

We’ve already picked up 1″ to 2″ in the metro, so another 5″ to 10″ looks good for much of the Twin Cities…grand total of 6″ to 12″ by Thursday night.

Craig Edwards will have updates as the storm unfolds Thursday.

PH

  • Dan

    Paul, I’m very curious about the current weather map. Int. Falls is at 40 degrees !, Bismark is at 37, the Twin Cities is at 38. With all that warmth how is going to snow 8-12 inches? Is it possible that there might be a lot of rain instead of snow for this impending storm?