Coldest Weather Of The Season On The Way

The Earth Systems Research Laboratory (ESRL) and the National Centers For Environmental Prediction (NCEP) are agreeing on a strong negative EPO going into the first week of October, something that could have major implications on temperatures.

The East Pacific oscillation, or EPO, has a positive and negative phase. In the positive phase, a stormy pattern in the West and warmth in the East is a common sight. However, these two agencies are both predicting a very negative pattern. This would lead to an enhanced potential for cold air to work its way into the East, while high pressure sets up across the West.

The Arctic Oscillation, another major factor in bringing cold air to the States, looks to be dropping negative going into the first week of October. This negative EPO, combined with the negative AO looks to be a perfect storm for some cold weather.

These two indices look to produce a very chilly first week of October for the East. I would not be surprised to see cities like Chicago, Milwaukee, or possibly Indianapolis reaching into the 30's, possibly getting below freezing at times.

You heard it here first at The Weather Centre!

Andrew