La Nina Making An Impact On Alabama

You may be asking the question, what is going on with the weather? Why is it so dry? And why are we experiencing mild temperatures on occasion? To try and help explain the current situation, the broad patterns that we’re experiencing are linked to other atmospheric processes taking place over the northern hemisphere. If you take a look at large scale satellite images you will notice all clouds and movement of storm systems travels like a fluid in motion; all these processes are interlinked. Therefore, we monitor conditions upstream with regard to understanding weather systems moving our way. For example, if certain atmospheric processes are occurring over the central Pacific that might cause more storms to occur over parts of the U.S. Obviously, the systems that develop will end up impacting the U.S. with certain parts of the country dealing with more active weather. We refer to these sorts of conditions that influence other atmospheric processes as teleconnections.

One popular index we monitor is known as ENSO, The El Nino Southern Oscillation Index. This index is used to monitor the strengths and weaknesses of El Nino. The El Nino cycle is an occurrence in which warmer water temperatures develop in the eastern pacific. The opposite phase is La Nina in which cooler water pools in the eastern Atlantic. According to the Climate Prediction Center, we have entered a La Nina phase, which has influenced the drier conditions in the southeast, along with the milder conditions. This phase is expected to continue through the rest of December. The La Nina pattern forces the primary storm track northward and we will continue to experience the trend according to the ENSO index. Hopefully, I have been able to answer some questions and I will try to elaborate more on this topic in the days ahead. For more information on ENSO click here.

(Image Source: CPC Sea Surface Temperatures) 

Wes Wyatt
WVUA Chief Meteorologist

Advertisements

Friday Afternoon Forecast Discussion Update

Get ready for quite a ride temperature-wise! The up and down temperature pattern we’ve experienced all week will continue this weekend as highs will be rising into the 70s. A high pressure ridge is building overhead and this pattern will resemble more of a summer setup as warmer air aloft builds in. We will have periods of clouds and sunshine tomorrow and Sunday. There could be a shower as some moisture builds into West Alabama. Therefore, I’ve included a small chance of a shower. The rain that does manage to pop-up will be quite scattered and isolated in nature. So I wouldn’t worry about canceling any outdoors events you may have planned. If rain starts falling in your neighborhood it should pass over fairly quickly. It’s not out of the question that a few spots in the state will hit the 80-degree mark, which would mean some record highs could be reached.

As the warm air continues to build over the southeast, a sharp front will develop over sections of Louisiana, Arkansas, and Missouri. The tight thermal gradient that develops will energize a storm system pulling out of the southwestern U.S. The central parts of the country will be dealing with the rain and thunderstorm development. Around here we will remain unseasonably warm and dry for Monday and Tuesday. Once low pressure ejects out into the Plains States the associated cold front will begin sliding eastward and the front will be on our door steps on Wednesday. This will bring us our next best chance for measurable rain area-wide for Wednesday and Thursday. The window for rain won’t be long however, as another cold and dry air mass will drop in on Friday, with a mostly sunny sky returning.

Have a great afternoon and don’t forget to check our video player this evening for an updated WVUA weather webcast.

Wes Wyatt
WVUA Chief Meteorologist