Top of the White House Christmas Tree, Nov. 30. (Joe Flood via Flickr)

November offered a winter appetizer, with the most snow in the month since 1989 and coldest temperatures since 1997.

If you love winter, then December should offer some more excitement. The pattern is shaping up so that we should have some colder stretches, as well as opportunities for snowfall, starting in the first 10 days.

December quick look

Temperatures: We predict temperatures to run near to below normal. It has a chance to become the second colder-than-normal December in a row. The average temperature should end up somewhere from 38 to 41 degrees (the 30-year normal is 39.7 degrees).

Rain: We project a continuation of wetter than normal conditions, with enough rain to make 2018 the wettest year on record. The total amount of rain and melted frozen precipitation should reach 3.5 or more inches (the 30-year normal is 3.05 inches).

Snow: November’s snow was above normal and, with December’s 30-year average of only 2.4 inches, I believe we can do it again. We have a chance of snow this weekend and, even if that misses, should have additional chances later this month. My call is for four inches or more for December.

But if you like snow in December, consider this cautionary note: Recent history has not been kind, and it’s generally not a particularly snowy month. The average snowfall is only 2.3 inches compared to more than five inches in January and February. And since 2000, December has experienced snowier-than-normal Decembers only five times:


Forecast rationale

Despite some underwhelming Decembers for snow in recent years, there are some ingredients to at least tilt the odds toward a bit more snow this year.

The Blob: A big area of warm water currently present in the North Pacific Ocean tends to be associated with high pressure over Alaska, which, when present, helps deliver cold air into the Lower 48.

El Niño: An El Niño event, characterized by warmer-than-normal ocean temperatures in the central and eastern tropical Pacific Ocean, is developing. Above normal precipitation tends to occur in the Southeast and Mid-Atlantic during these episodes.

Satellite (AVHRR) estimated surface temperature anomalies showing Blob and El Niño areas

Head start: The first half of December is expected to end up about two to three degrees colder than normal based on current models. A storm coming up from the south is possible this weekend, which could deliver snow. However, uncertainty is very high about how far north it will come.