Radar indicates snow already to our NW.
This should work down I-24 this morning, and mainly impact areas along and north of I-40. There is not much of it, but as I write this, temps at the surface and aloft are all below freezing, so it should be snow. Yet the air aloft is also pretty dry, meaning much of this snow will evaporate before we will even see it. So, we think this will be a little “pre-event” light snow, but not a big deal.
Heavier precip arrives around lunchtime, through the afternoon, and into tonight.
Meanwhile, as we go through the day, above-freezing temps will arrive from the southwest to the northeast, changing the precip from snow, to a wintry mix, to rain. Right now, NWS-Nashville thinks we’ll have snow/wintry mix from around lunchtime to sunset, then rain after that. Expect less snow/mix the further south you are, and more snow/mix the further north you are. Tonight we think all the precip will turn to rain. Temps will continue to rise, and rain will continue overnight into the early morning hours, replacing the worry of an icy commute with a wet one.
As NWS-Nashville wrote this morning, we think if this forecast is going to go wrong, it’ll do so by giving us less snow/mix and more rain. That would suggest a transition to rain before 6 PM, perhaps much earlier than that for those in Williamson County.
The HRRR model sure seems to think so. Notice how it thinks this is an ALL RAIN event for us.
The NAM4 model has very little snow south of 40 — almost all rain — with more mix than rain north of 40, but very little snow.
Both models suggest this may be rain instead of snow this afternoon, but being on the ‘transition zone” prevents us from having high confidence. Again, more rain, less snow south. More snow, less rain north.
This is a classic “nowcast” event. We fully expect this will have to be adjusted as we go through the day, which we will be doing on Twitter @NashSevereWx.
This website supplements @NashSevereWx on Twitter, which you can find here.
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