The very low Arctic Oscillation (AO) is one of the key features we are watching as the best indicator of the very cold weather across the eastern part of the country. When the AO is positive, typically the cold air remains north, but when it becomes negative, that indicates cold air can come south into the U.S. In this case, we have a very low AO as indicated on the graph below. As you can see, the value is at the extreme levels which is why we are seeing the very cold weather. Also notice, the AO goes up dramatically by the 1st of the month, so if that is correct, we should see the cold weather relax about that time. It does not mean we are going to have a complete reversal in the pattern, but it does mean the extreme cold should ease-up.
Before we get there, we have a storm this weekend and another next weekend. The maps below show the snow and severe weather areas for the storm. In fact, D.C. and Baltimore may get some snow Sunday night because it will be colder then the previous storm that did not produce any in the cities.
Quiet week as high pressure dominates the eastern part of the country.
A cold front will produce severe storms across the Midwest Saturday. Odile's remains will bring more flooding problems.
Heavy rains from Odile will spread across southern New Mexico into Texas. Flash flooding may occur.
Dangerous flooding will occur as Odile heads into southern Arizona.
Odile will bring some serious flooding to parts of Arizona into New Mexico.
Flash flooding will be the big story across the Southwest this week.