February 27, 2012 10:14 AM
A very strong Winter Storm is headed for the Sioux Empire, bringing with it heavy snowfall, rain, and freezing rain. Here is an update on what you can expect in the next couple of days.A very strong low pressure is set to eject out of the Rockies Tuesday that will intensify into a very potent winter storm for those of us in the upper midwest.
(Nam Forecasting Model valid 0z Weds)The forecasting models that we use are in good agreement on the basic size, shape and track of the low pressure one very important factor differs which makes this forecast a very difficult one and that is just where the warm front will set-up and where it will go.
(Nam 850mb map valid 18z Tuesday)One model shows the warm front setting up north of I-90 and South of Highway 14. This would mean that locations within the warm sector are more likely to see rain and freezing rain. While areas north of the warm front will likely see all snow. This particular model would suggest rain or freezing rain to start off the morning Tuesday south of Highway 14.
(Nam model 850mb Temperatures valid 0z Weds)As the low moves across South Dakota Tuesday afternoon, cooler air will slowly filter to the south and east. By Tuesday drive-time, rain/freezing rain should turn over to snow north of I-90.
(Nam Model 850mb Temperatures Valid 6z Wednesday)By Midnight, almost the entire state of South Dakota will be experiencing much cooler air moving in and all remaining rainfall will likely return to snow and even sleet. Winds behind the front will also whip up creating blowing snow and drifting.This system is very important to watch because this low is very powerful and has a lot of moisture associated with it. Areas that see all snow will likely see over a foot and even nearer to two feet, add winds gusting near 40 mph and drifts will be well over 4 feet. Area's in the SE which will likely see snow changing over to freezing rain will see ice accumulations around a quarter of an inch, finishing with a couple inches of snow. Gusty winds, blowing ice covered tree's and powerlines could cause power outages.
Keep in mind that areas of ice, rain and snow can and will change over the next 48 hours depending on where the warm front sets up and how the low actually tracks. If you do have travel plans you need to stay updated as this storm will have a very high impact on travel for the next 4 days or so.
(West Forecast)As always, we will continue to update as the forecast changes. You can always get up to the minute updates from KDLT.com and our twitter page.