Another Spring Cold Front

The weather yo-yo of spring continues today and tonight with the approach and passage of a spring cold front.  

The 6Z GFS shows the cold front moving across northern Utah tonight at 0600 UTC 18 March (0000 MST Tuesday). 

Ahead of the front, today will be mild and windy with the possibility of blowing dust.  The prefrontal environment today looks to be mainly dry, although I wouldn't be surprised to see a spritz or two of valley rain or mountain snow.  Precipitation is not expected for the evening commute.  

The front drags through tonight.  Onset time, duration, and accumulations for the valley vary some from model to model.  For brevity, I'll focus here on the 1200 UTC initialized HRRR.  The time-series below is for the Salt Lake City International Airport.  Precipitation onset is just before 11 PM local time, but the turnover to snow doesn't occur until after 2 AM.  I'm not sure if I'd count on that timing given the uncertainties at play, but expect precipitation to move in tonight and at some point to turn over to snow at all elevations.  

The HRRR produces a bit under 3 inches of snow at the Airport by 8 AM tomorrow morning.  Bench accumulations would likely be greater.  Below is the NWS infographic for this event showing the expectation for 1-3" for the Salt Lake Valley floor and 2-6" for the benches.  

NWS infographic downloaded 9:30 MDT 17 March

For the mountains, I suspect Tuesday will be a pretty good powder day, but you didn't hear that for me.