Wednesday, October 5, 2011

La Nina Could Last Another Year

The weather phenomena known as "La Nina" is likely to persist for another year, which means our exceptional drought status could remain the same for a second year.

My college professor at Texas A&M University, Dr. Nielsen-Gammon, spoke Monday at a climate workshop in Fort Worth. He is our state climatologist and has been reiterating the fact that no significant rain relief looks to be in the offing at this point as La Nina is expected to strengthen and last for at least another year.

If there is any good news, it's that Nielsen-Gammon says there is only a 25% chance that Texas' drought will persist for another five years.

La Nina is a weather phenomena associated with cooler than normal sea surface temperatures in the equatorial Pacific Ocean, as seen by the image to your left. It is these abnormally cooler water temperatures that alter the weather patterns across the globe and can influence a region's temperature and precipitation outlook.

Unfortunately for us in East Texas and all Texans across the state, it means warmer and drier than normal conditions throughout the entire year. It just so happens that this particular phase of La Nina is stronger than normal, which has led to the worst drought in over 50 years.

What Lies Ahead

With a persisting La Nina, we would see a dry fall and winter, which would only worsen the ongoing drought. We would also see a few cold blasts, but the overall trend would be warmer than normal conditions when averaged out for a two or three month period.

With very little rainfall and strong winds blowing in behind cold fronts, the fire threat will also be increased. The combination of dry fuels, low relative humidity values, and gusty winds means the wildfire season could get worse.

Going into next spring, we could see a few severe weather outbreaks that are more violent than normal. If you recall, we had a very active spring earlier this year with several tornado reports. We had two consecutive nights of active tornado warnings this past April. This was part of the storm system that ended up producing the violent tornadoes across Dixie Alley in the days that followed.

History has shown that La Nina years have more severe weather episodes and that's not good as it means any chances for wet weather in the spring will come at a steep price.