The lowcountry has been blessed with an overall mild January, but this trend will likely change as we head into a new month as long range weather models are bringing the cold back this February.
From late December and into early January, the jetstream was set-up well to our north and effectively held back the coldest air as we breezed our way through what is usually the coldest weather of winter. Temperatures ranged from around 10 to over 20 degrees above climatological normals for that time of year. While eastern US was sitting pretty and warm, the western US was staying cold as that jetstream buckled. This pattern is looking to switch- warmer in the western states and colder in the eastern states as we kick off February.
Forecasts become muddled the further they go out. Generally 7-10 days is the accepted time frame for accurate numerical forecasts. Long range forecasts are a bit tricker and focus on trends instead of numbers. Think of the upcoming big game this Sunday. Most could have predicted accurately at the start of the season that the New England Patriots were going to end up there, but trying to predict the final score in September would be ridiculous. Long range forecasts can do the same by forecasting trends: above or below average temperatures and rainfall, but cannot accurately tell you if it’s going to rain on your event three Saturdays from now. To determine these trends climatologists look at a broad view of complex weather patterns and how they will evolve. Some of these you may have heard of- El Nino and La Nina, while others are less renowned (possibly because they don’t have cool names but rather just abbreviations)- MJO.
With that in mind, the Climate Prediction Center (CPC) has indicated that temperatures below normal (which this time of year is right around 60 degrees for the high) is likely for the end of January and into the first week of February. This pattern will likely continue for the first half, but may moderate to a nearly normal or even warmer than average pattern by the second half. What this means for us is that it will be much less likely for us to see days with well above average temperatures. Understand that this is a general trend- there will likely be a day or two that will end up warm as daily fluctuations are not included (remember the football analogy!). Also take into consideration when you see that map is that the color of blue does not indicate how cold it will get, rather it indicates the likelihood that temperatures will trend colder (darker blues= odds are better).
So keep those jackets ready as we head into a new month, but the good news is that February is the turning point annually where our average temperatures begin to warm!