Severe thunderstorms with tornados across the southeast quadrant of the U.S. this past weekend included snow and winter-like cold in their wake observed deep into the central U.S. limiting daytime high temperatures near Chicago to the mid 30s. The next vigorous Pacific storm which moved onto the West Coast today is also near certain to produce blizzard conditions and 10° below average temperatures or greater deep into the central U.S. once it ejects east of the Rockies Wednesday, followed by sharp cooling across the Midwest and East at the end of this workweek (Mar 20-21). Spring- like volatility and the mild nature of Pacific flow flooding the U.S. between storms virtually ensure above average mean temperatures will continue to predominate several day periods across the Eastern half of the U.S. through the next full week. However markedly colder air is near certain to settle into the majority of the Midwest and East by Mar 26 in a more sustained manner, while the West warms (and dries). Greatly improved model forecast consensus completing full atmospheric pattern reversal early in the final week of March is the closest yet to long standing 30-day MWA ensemble forecasts, but government models appear far too fast to breakdown the colder Eastern pattern before March is over . Longer range 30-day MWA ensemble forecasts remain most stable; maintaining unseasonably cold air reinforcement substantially longer into the northeastern quadrant of the U.S. throughout early April, including brief intervals of 10°-20° below average temperatures and late season snow across the Great Lakes and Northeast. Even typically warm biased CFSv2 model forecasts valid during the 1^st week of April flipped temperatures several degrees below average, adding confidence to prolonged interruption to spring across the northeast quadrant of the U.S. until milder air can fully return in a sustained manner in late April.