La Nina fail?

We are in the midst of a La Nina winter. I discussed in my blog two weeks ago how in a La Nina year, we should experience above-average temperatures and below-average precipitation. While we did have a few days of warmer-than-normal temperatures following that blog post, the cold returned with a vengeance, and it looks like it will stick around for a while.

On December 21, the Climate Prediction Center updated its outlook maps for January and the three-month period of January through March. According to those maps, North Carolina now has “equal chances” of having above-normal, normal, or below-normal temperatures and precipitation through January. I usually interpret that prediction as “your guess is as good as mine.”

CPC Jan Temps

The Climate Prediction Center’s Temperature Probability map for January 2018

Based on the long-range forecast models, it looks like we will have below-normal temperatures through at least the first full week of the month. While I don’t really trust the models almost two weeks in advance, I don’t see anything today that would make me think this cold pattern will break before January 8. So, at least the first week of January should be colder than normal.

If that first week ends up being wetter-than-normal as predicted in the CPC’s 8-14 Day Outlook, we could have some wintry precipitation. While that possibility should be expected in January, it does make me wonder where my milder winter went? Granted, climatological winter lasts through the end of February, but much of December was cold and the first part of January looks even colder. I’m feeling a little gypped and wondering if we are experiencing a La Nina fail.

But I digress.

The updated outlook for January through March still shows the likelihood for warmer-than-normal temperatures and below-normal precipitation. That map tells me that the forecasters at the CPC are still clinging to the idea that La Nina will win out over all the other factors that go into seasonal forecasting. I’m having a hard time buying it as I look at the local forecast today. Since I’m not a cold weather fan, I will cross my fingers that they are correct.

One thing to keep in mind is that these monthly outlooks are basically about average temperatures over a month or three-month period. If January verifies as a warmer-than-normal month, that would mean the last three weeks in January were likely well-above normal. Another point to remember is that a winter storm only takes a day or two to make a mess of central North Carolina. Just because the next three months could be warmer on average doesn’t mean we can’t have late season wintry weather. Ice storms happen pretty regularly for us in February and early March.

I’m always curious to see how these seasonal forecasts pan out. Every one that verifies true gives us more confidence. Each one that turns out to be a bust teaches us something. For now, all we can do is bundle up against the current cold streak and wait to see what the new year brings.

CPC JFM temp map

The Climate Prediction Center’s Temperature Probability map for January through March of 2018