Tuesday, November 17, 2015

Minor accumulating snow this weekend, but we first have to get through the rain Tuesday night

The rain has been coming down in full force all afternoon and evening and isn't showing any signs of letting up anytime soon.

Many locations have recorded either close to, or over, an inch from earlier today.  And with what's coming down now (as of 8:30pm) we'll likely add on at least another inch when all said and done.  This would bring overall totals near the two inch mark by Wednesday morning.

Another thing you'll notice with the heavier rain is the wind increasing.  Southeast winds have been gusting at times to 30 mph.  Look for those wind gusts to continue into the night and Wednesday.

I was going to post another video update for tonight, but it is taking FOREVER to load.  I figured it would be easier for me to type it all out than wait.  So here goes...

The cold front that pulls through Wednesday morning isn't going to have much cold air behind.  Temperatures Wednesday could actually rebound back into the low 60's with strong southerly winds.  There will be scattered showers through the day, with possibly a little more light rain Wednesday evening.  By Wednesday night, that's when the cold air arrives.

Thursday is going to be windy.  Temperatures will only warm to the middle 40's, which is where we should be mid-November, but it's going to feel a lot colder.  Combine that with wind gusts to 40 mph and it will even feel down right blustery.



The heart of the cold air arrives Friday.  Temperatures will still remain above freezing during the day, but drop below freezing at night.  The weather-maker in all of this snow talk is low pressure that is quick to develop along the leading edge of the cold air early Friday.  Models have been fairly consistent in pulling a swath of precipitation from the Plains through Iowa, northern Illinois and southern Wisconsin before shifting east.  However, timing of the precipitation is still off and strength of this low remains different between the models.

Having said that, I do think that Friday night there will be a period of snow that could produce a coating on the ground by Saturday morning.  There are a couple factors that need to be monitored, though, before anything close to snow totals come out. 

The first couple are the reasons stated above, but if we look at soil temperatures - two and four inches deep in the ground - those numbers are in the upper 40's and low 50's.  Now, they will probably fall the next couple of days, but we don't get into the heart of the cold until the precipitation is supposed to begin.  Having a warm ground at the onset could offset any of the accumulation.  However, get snowfall rates that fall fast enough and that may be enough to overcome the warmer ground issue.

Also, any precipitation that falls during daylight would likely be liquid rather than all snow.  It wouldn't be until surface temperatures fall close to and below freezing that we would begin to see that transition over to snow.

Bottom line, I feel fairly confident that there will be snow this weekend - majority of it arriving Friday late into Saturday.  However, regarding any sort of amount, or whether or not the shovel or snow blower need to be dusted off, that confidence remains relatively low.  The probability of us receiving one to two inches is high, but not zero for anything above that.

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