As observed last August, a large region of warmer-than-normal sea surface temperature anomalies (SSTA) in the west/northwest North Atlantic basin correlated to a blocking high pressure ridge over northeast North America caused Major Hurricane Harvey to stall over Texas and produce 50 in. of rain in the Houston area. A similar set-up is in-place this week (into next) to cause Florence, forecast to become a major hurricane to also stall in the Mid-Atlantic region bringing historical and catastrophic flooding.