Tuesday, November 16, 2010

La Nina Setting in This Winter Season

This time of year, I run into people all the time wondering just how cold our winter season will be in 2010-2011?

As you know, I am a meteorologist, and mainly focus on short term forecasts (3-7 days out). We do have a group of weather scientiests that do focus on long term forecast change, based on weather pattern studies.

We call them climatologists, and just recently, the National Oceanic and Atmospheric Administration (NOAA) released their precipitation and temperature outlook for this upcoming winter season. This includes the three month period of December 2010-February 2011.

We are looking for drier than normal conditions, while parts of the Pacific Northwest and Northern Plains are anticipating a wetter than normal winter season.

Considering we are currently in a moderate drought, this certainly is not good news, as ground soils are very dry.

In terms of our temperature outlook, we are expecting warmer than normal conditions. Again, this does not mean we won't see some hard freezes or cold blasts, it just means over the three month period of December -February, our average temperatures should remain above our normal climate values.
It should be noted that this past winter (2009-2010) was colder and wetter than normal, as we had an El Nino type weather pattern in place. If you recall, we had some record low temperatures set last year with three different snowfall events.
Based on current trends with sea surface temperatures, jet stream patterns, etc., we are settling into a La Nina type weather pattern, which is just the opposite of El Nino.