Friday Afternoon Forecast Discussion Update

Christmas is almost here and today it sure feels far from Christmas-like. I do want to mention that our weather graphics on the site are currently being updated so bear with us. We are trying to get everything switched over due to our new graphics platform. I did want to briefly mention some things about the higher winds yesterday. This was due to what is called a “gravity wave.” I know this took many of us by surprise as we had light winds and a steady rain, which suddenly transitioned into a high wind event. A gravity wave is a strong propagation in the flow or as it’s called a wave, caused by density differences in the air. When the wave is present this can enhance uplift. The air rising or being lifted then cools and becomes dense, later sinking towards the surface in the form of gusty winds. I’ve had several question regarding this term and wanted to hopefully provide some answers. This event led to lots of trees being downed and people loosing power yesterday.

Today turned out just the opposite, with calm and tranquil conditions. Tomorrow we will top out near 70, but the parade of storm system will begin. Tomorrow the winds will grow quite gusty and we will have a cold front moving in tomorrow night. A band of rain will march through tomorrow night and there could be some thunderstorms. The threat for thunderstorms however, will mainly be in areas south of Tuscaloosa.

We will catch a break through much of Sunday and Christmas Eve Day. A shower could pass over by Christmas morning as moisture begins to lift into Alabama again. We will bottom out in the lower 30s Christmas morning, but we should stay above freezing. More showers will be possible with temperatures rising on Christmas day. Low pressure will move in on Wednesday and bring us a good chance of rain for the day after Christmas.

The long range data is showing another storm system taking a similar track late next week for the Friday/Saturday timeframe. As the year 2007 comes to a close, there is a chance we will be talking lots of rain for the last weekend of the year.

Wes Wyatt
WVUA Chief Meteorologist