There is historical precedent for N&W trend w/ decreasing lead time for synoptic regimes similar to Saturday. 1/7/17 & 2/5/16 had short term NW trend w/ similar right entrance region to anticyclonically curved jet.https://t.co/ZgwykM4Sz8 pic.twitter.com/LDugbjP3tF

— Tomer Burg (@burgwx) December 7, 2017