The pattern near the potential coastal storm is quite anomalous - mainly the ridge and blocking high pressure that expands to its north. The GEFS suggest nearly 100% chance that 500hPa heights are above the 97.5th percentile, and an 80-90% chance they exceed the 99.5th percentile pic.twitter.com/IguMKrw8st

— John Homenuk (@jhomenuk) October 6, 2019