Winter Storm Approaching Tennessee

Check out the latest Watch/Warning map provided from the National Weather Service:

 

 This map gives a good picture on the Winter Storm expected to affect us here in Tennessee. The well-defined strip of pink represents Winter Storm Warnings issued by the National Weather Service. The dark blue outlining the pink represents the Winter Weather Advisory's. It is very evident this system is moving east-to-west by observing the map as a whole. 

Memphis, Nashville and Knoxville is expected to pick up 3 - 8" of snow/ice accumulations between Friday morning and Saturday night. Amounts will vary depending on the location. 

As observed on the map, portions of south-central Tennessee have been reduced to a Winter Weather Advisory. According to a blog posted on newschannel9.com, Chattanooga has been an incredibly difficult area to forecast. A difference of 1 - 2 degree can be the contributing factor to this system producing rain or snow. Forecast models are favoring a slightly warmer Friday night resulting in more rain with sleet/snow mixed in.

For all areas, travel will be especially hazardous because this system will produce a layer of ice before turning to all snow.

Oh how I wish I was up in Nashville right now. I have not had the opportunity to measure new snow with my CoCoRaHs tools yet. I recently studied how to measure water content in a core snow sample to determine how much moisture the ground receives in any given winter storm. The myth that 1" of rain equals 10" of water has been proven to not be reliable. Varying temperatures tend to increase/decrease the water content of fallen snow. According to the training slide show for CoCoRaHs volunteers, measuring the exact water content withen a snow core sample is important for hydroligists and river forecasters to know exactly how much water the earth is receiving, and how much water will potentially run off into rivers and streams upon melting.

The snow expected to fall this weekend at my CoCoRaHs station (TN-SR-55) will have little-to-no melting by the time I arrive on Sunday afternoon. So I will still be involved with recording water content as the melting occurs.