Winter Storm Forecast Discussion and Timeline: Monday & Tuesday
More details have emerged this morning and we're getting a better idea of impacts and timeline.
- Snow & gusty winds are already moving into areas of Northeastern Wyoming, having impacts on travel and road conditions.
- Rapid City will slowly see conditions deteriorate going into the lunch hour and into the afternoon
Here’s a quick look at the updated radar across the region.
The Rapid City traffic cameras have not updated since 2/12/21
Rapid City - North
Rapid City - South
Here are updated road conditions across the region.
- Most of the region is under a winter weather advisory or winter storm warning, save for the Weston County plains in Wyoming and portions of the Southern Black Hills.
- Several inches of snow are likely, combined with 40-50 MPH wind gusts this could lead to difficult… if not impossible travel at times.
- The I-90 corridor between Rapid City and Sturgis specifically has a winter storm warning for 6″-10″ of snow.
- Some of these higher amounts could creep into the northern and western portions of Rapid city, particularly if northerly winds push the snow into Rapid City from the North.
- Box elder and Ellsworth AFB could also see higher totals than the advised 3″-5″ with blowing snow coming around the Black Hills from the Northwest and piling up.
- Snow is already moving in from Northeastern Wyoming into the Black Hills, and will continue to do so through the lunch hour.
- The system will start pushing Northeasterly winds into the Black Hills, leading to upslope enhancement along the I-90 corridor.
- This will be combined with windy conditions, leading to patchy blowing and drifting snow and low visibility.
- Winds winds winds, that’s the big deal with this winter storm as snow accumulations will blow around and make clearing roads difficult.
- Northwesterly winds are expected to turn Northeasterly towards Sturgis and Meade county by Monday evening, and this will lead to larger snow accumulations in that particular area.
- Conditions are expected to deteriorate this evening, as colder temperatures and higher wind gusts make travel difficult, and at times dangerous.
- We will have road conditions and radar posted to both this blog and our website, you can check those out at anytime and they will update automatically.
- Tuesday morning commute will continue to see snow bands and gusty winds criss crossing the region, with travel advisories being likely.
- Upslope snow will continue for the Northern Hills and the Eastern foothills.
- Finally by late morning Tuesday we’ll start to see improvements as winds begin to subside and snow bands lose energy as our low pressure system exits the region.
- Stubborn snow bands will stick around the usual trouble spots in the Northern Hills and Eastern foothills.
- Gusty winds could lead to continue blowing and drifting snow, even if snowfall has subsided.
- Tuesday night sees tangible improvements with partly cloudy skies and fairly chilly temperatures.
- Roads will freeze, so icy conditions will be possible even if the storm system has exited the region.
- Northeastern Wyoming will see a little less than the rest of the region, with 2″-4″ expected generally and 4″-7″ towards Sundance and the Bear Lodge Mountains.
- The Northern Hills will be a mixed bag, but overall high accumulations should be expected. 14″-20″ towards Cheyenne Crossing and Spearfish Canyon, while Lead and Deadwood could see around 12″-16″ generally.
- Spearfish could see 8″-12″, but a sharp drop-off as you head towards Belle Fourche with 3″-5″ likely there.
- From Whitewood along I-90 towards Sturgis and Tilford could see amounts above 6″-8″…. I could see areas near Nemo pushing a foot of snow. It’s all about the Northeasterly winds!
- Rapid City is a tough cookie, it’ll be right on the edge of vigorous snow bands just North and East of town and a sharp drop-off as you head towards Hermosa where 2″-4″ is more likely. I think 4″-7″ is very reasonable (much higher than yesterday’s forecasted totals of 2″-5″!) with the Southeast side of town seeing the 3″-4″ range and the Western side of town seeing the 5″-7″ range.
- Box Elder will be a mess – seeing as it doesn’t really matter how much snow actually “falls” there, as most of it will be blowing right around the Black Hills from the Northwest and pushing right up against the community and Ellsworth AFB. 3″-5″ seems a reasonable “accumulating” estimate.
- The SD plains in general will see the higher winds, and several inches of snow ranging from 2″-4″ to maybe even 3″-6″ of snow towards Pine Ridge and Eastern portions of our area towards Ziebach and Haakon County.
- Carter County, MT, along with Harding and Perkins County may see a *tiny* bit less – but the winds mean travel impacts will be the same with snow blowing over the roads and low visibility at times. 2″-4″ to maybe 3″-5″ in those regions.
- Newcastle, Edgemont and the Southern Hills will see a big drop in totals due to Downslope winds (opposite of upslope effect of increased totals). Some areas could see as little as a dusting.. but a general 1″-3″ of snow seems appropriate. Winds will still be a factor though, so don’t let your guard down – especially as you leave the safety of the Black Hills towards the Great Plains along SD-79.
It’s all about impacts here. Yes, totals have gone up since only 24 hours ago – but the impacts will still be relatively the same with high winds being the big deal here. Even if you end up only getting 1″-3″ of snow, combining it with 50 MPH wind gusts will ruin anyone’s day. Dropping temperatures Monday night will freeze up roads as well, so doing your best to stay off the roads will be a wise move. If it ends up not being so bad and the radar clears up for a bit, more power to us… but don’t expect it to stay that way for long as we are still talking about a Clipper like system here with hit-and-run tactics.
Snow ratios will be the key here. Winds should chop up snowflakes into smaller pieces and lead to smaller overall totals… but any dip in the winds could lead to large, fast-accumulating wet snowflakes. Temperatures will be hovering right around the mid to upper 20s, even 30s in some cases. This will allow higher dewpoints and greater moisture content. So, whether its high winds or large snowflakes you’ll be likely getting either or… but hopefully not both.
I’ll make sure to keep road conditions and weather updates current on this page throughout this storm, If you have pictures or information please send them in! You are our eyes and ears out there, and we’ll be sure to pass that information along to the National Weather Service. I understand these snow totals have crept up on us, and we appreciate you tuning in with us as we continue to monitor this system, we know these updates are important.
Be safe out there. – Brant