NEW: Central US Winter Storms February 2021 UPDATED: Arctic Amplification UPDATED: Winter Storm Risk Increase Tweet: 500 mb heights over the Four Corners region near NAEFS max by Shawn Milrad on Twitter Original Tweet: 500 mb heights over the Four Corners ish region might be max in the NAEFS [North American Ensemble Forecast System] climo this Mon-Wed Go to Site Related Events Southwest US Heat Wave June 2017