A Look Back at the 2009-2010 Winter Forecast
The 2009-2010 winter forecast was the first seasonal forecast that I was asked to give at ABC6. Like this year's forecast, I spent many hours researching weather patterns, history, and computer models to try and decipher what the winter would be like in Southern New England. Let's take a look back at how that forecast turned out.
Question – Will it be a snowy winter?
My Answer – 35-45″ snow – slightly above normal
Reality – 31.5″ at TF Green Airport
Analysis – The forecast wasn't too far off, and I thought it was in the bag after the 16″ snowstorm in December. In hindsight, I probably pigeon-holed myself a bit with the narrow range of 35-45″. There were some parts of RI and SE MA that fell comfortably within that range. As it turned out, TF Green Airport was not one of them. All things considered, I can live with a 3.5″ error on a seasonal snow forecast. Heck, I've had more than a 3.5″ error on a single storm snow forecast!
Question – Is it going to be a wicked cold winter?
My Answer – 1° warmer than normal
Reality – Dec-Feb averaged 0.5° warmer than normal
Analysis – The winter started out cold. December was about 1° below normal. As the winter progressed, it gradually got milder. Both January and February were warmer than normal. In the end, my forecast was fairly accurate.
Question – Are we going to see a big snowstorm of 12″ or more?
My Answer – Yes
Reality – Yes. 16″ from the storm on December 19-20, 2009.
Analysis – I was out on a limb a bit on this one. Typically, there is a 20% chance of a 12″ snowstorm in Providence in any given winter. I figured with the El Nino pattern that we would see a few intense storms. I thought that we'd really get nailed if one of those storms was far enough offshore to keep the cold air locked in. Lo and behold, winter hadn't even officially started and we got dumped on.
Question – Will we see a white Christmas?
My Answer – Yes
Reality – Yes!
Analysis – Admittedly, I was relying on the big guy for some help on this one. Santa's magic came through as the ground was still snow-covered on Christmas day as a result of the blizzard less than a week earlier. Why did I need help from Santa? There is only a 37% chance of a white Christmas in Providence.
Question – What will the weather be like in Florida?
My Answer – Rainy, cool, some severe weather
Reality/Analysis – I nailed this one right on the head. El Nino almost always leads to an enhanced southern jet stream that brings a lot of stormy weather out of the Gulf of Mexico and into “The Sunshine State”. Last year was no exception as all three winter months received well above normal rainfall. December was slightly cooler than normal, and January/February were extremely cool – by Florida standards.
Seasonal forecasts are very trick, but I think this one went pretty well. If I had to assign a letter grade, I'd give myself a B/B+. I missed in both directions on the snow forecast. TF Green came up just short of my forecast, but some in Northern RI saw nearly 60″ of snow. The temperature forecast was decent. Honestly, the white Christmas forecast was done tongue in cheek, but I'll take it. The whopper snowstorm and Florida forecast actually panned out the best.