Rollercoaster Ride to Christmas Day
Our temperatures are on a wild ride in Oklahoma this month. Day-to-day, we are seeing 15° or more swings. This is not atypical for the start of winter as the powerful polar jet stream sinks further south, creating more powerful storm systems and bigger air mass changes as a result. The one thing our recent pattern hasn’t brought is moisture. As we continue to dry out, wildfire danger grows and becomes a daily concern. There are signs of bigger changes involving moisture AND colder air as we get closer to Christmas.
Green Country continues to be caught in between much colder air centered by the Great Lakes and a large area of unseasonable warmth beneath a large ridge in the jet stream to our west. Above is our current weather pattern. The trough continues to pivot more energy on its backside southward, resulting in one-to-two day stretches of cold air before warmer air pushes back from the west. Today is one such day of colder air. Another one arrives Thursday with a day of unseasonable warmth on Wednesday. This pattern is keeping moisture locked in the Gulf of Mexico with a continued northerly flow. Any cold front that passes through Oklahoma is only noted by changes in wind and temperature.
By the weekend, the jet stream pattern becomes less amplified, which does open up the Gulf moisture to our area. While we may not see any real deal rainfall, cloud cover may increase and low-level moisture may help to offset fire danger a touch. There’s still a chance some places could see a few showers before that system pulls away. Being of Pacific origin, it won’t have any really cold air behind it. Instead, this swing between unseasonably mild and seasonably cool temperatures continues into next week.
Let’s jump to the weekend before Christmas. There are signs in our long-range computer models of a strong storm system developing to our west. Not only does it finally draw up significant moisture into the area, it latches on to some bitterly cold Arctic air. Lots can and will change in how this storm system evolves, but it’s likely to involve heavy rain and heavy snow over parts of the central U.S. The devil is in the details. Exactly where that storm system deepens and tracks will determine if we receive the brunt of the warm side of the system with rain and storms or the cold side with potential snowfall and Arctic air. The truth could easily lie in between with a little bit of both or even just another big temperature swing. Below is a general set-up we see for this storm system.
What you should know about Christmas weekend is that there is a higher-than-normal chance of active weather impacting travel. Precipitation amounts and types are extremely uncertain this far out, but there is growing confidence it will be getting cold right around the holiday. This at least provides us with a chance of seeing a White Christmas this year as shown below. In a week from now, we’ll have a better idea of the timing. In about 10 days from now, we’ll have a much better handle on what type of precipitation, if any, we see from it. Just keep tuned to this as our first real encounter with Old Man Winter could come at an interesting time.