Thursday P.M. – Friday A.M.January 21st, 2013 at 1:30 pm by Chad Evans under Chad's WLFI Weather Blog
Never take models for total face value…….I’m looking at the dynamic support & nice lift in the SGZ (Snow Growth Zone) Thursday p.m.-Friday a.m., which is why I prefer 4-6″ with some mix in southeast & south. I say mix in south & southeast because it still appears tongue of 0-2C air at 850 mb (5000′) will make it to I-74.
Impressive dendritic growth & snow ratios of 15:1 support more snow. Analog data showing similar situations shows a large statistical likelihood of more snow.
80-90 mph mid & upper winds with impressive mid-level vertical velocities & a 60-80 mph baroclinically-induced low-level jet nosing up into the Ohio Valley should promote a few hours of moderate to heavy snowfall as upper trough swings in. SGZ zone temperatures & moisture sure look ample for the prolific dendrite production. Also noticed frontogenical forcing with temperatures of -9C in our northwestern counties to 2C in our south in the 850-700 mb zone.
I’ve thrown out the NAM model, as it is not handling the cold air well & the GFS has too little snow here.
Will continue watch.