Friday, February 3, 2012

January Report Card

A former teacher of mine always offered this word of advice:
"If I get the forecast wrong, I want to go down on my forecast. Not someone else's."
It isn't a profound, thought-invoking quote but it always resonated with me. Best to own up to my own mistakes than say "it's not my fault". I do my best to follow the "station" forecast, or the show-to-show forecast. It's tough though when you have three or four different meteorologists forecasting and each have their own style!
So, I begin my "resolution" to track and improve my forecasting skills this year. I haven't done this before, so I have no measuring stick to gauge improvement. But after completing 1/12th of the mission, there is definitely room for improvement and you will see why!

I will grade myself on two categories: accuracy of daily high temperatures and overall sky conditions/precipitation for that day.  Out of the 31 days in January, I had a forecast for 21 of them. Each meteorologist and "consumer" of a weather forecast has their own definition of accuracy. I've always used the +/- 3 degree range in order to consider a forecast temperature accurate. As for the sky conditions/precipitation department, that is more subjective. If you'd like to judge my forecasts under your own parameters, well, you'll just have to wake up early and tune into the show each morning! So without further delay, here is the January Report.

January temperature accuracy (+/- 3 degrees of actual high temperature) was only 52%! 11 out of 21 days were accurately forecasted. Of the 11 correct high temperatures, only two of them hit the high temperature exactly! Not very impressive. I missed the high temperature by an average of 5.5 degrees (technically 2 degrees when you factor in the plus-minus). There was a run of six consecutive forecast days with a missed high temperature. Those days spanned the middle of the month (Jan. 18-26). Coincidentally, those six forecast days were right after the valley snowfall days. More on those snow days in a bit. So ultimately, my temperature forecasts have a lot of room for improvement. This January was somewhat challenging in regards to high temperature forecasting. We had several weather systems that would lead to strange high temperatures that would occur in the evening or overnight hours. I'm not making excuses, it's just something that adds a little difficulty to projecting an accurate temperature.

The Report does have a bright side though. The sky conditions and precipitation forecast was near perfect. 20 of 21 days had accurate conditions! That works out to 95%. The lone botched day was on the 23rd. I had called for some morning fog and a shower followed by some clearing during the afternoon hours. Turns out, it did not rain that day and we never really cleared out either. The day will go down as mostly cloudy. I also missed the high temperature that day. But that was it! Nailed the 20 other forecast days!

During the month, Portland saw some where near 5" of snow. It all fell in a four day period from the 15th through the 18th. I will list out my exact forecast thoughts for each day below:
Sunday, 15th: Trace-1" of snow at the lowest levels. Snow showers tapering off in the afternoon. High 40.
We officially picked up a Trace of snow in Portland and the high temperature was 38 degrees.
Monday, 16th: Mainly dry morning with some snow showers in the afternoon. High 39.
Officially saw 0.08" snow during the afternoon. The high temperature was 38 degrees.
Tuesday, 17th: Rain/snow mix at times, sticking at about 1,000 feet. A south wind helps warm us. High 40.
We saw a rain/snow mix (I think it was more snow than rain) and that South wind (10-20) warmed us up to exactly 40 degrees!
Wednesday, 18th: Rain/snow turns to all rain by 7am in most metro area. A high of 48.
Snow only fell in the early morning hours, the rain began by 7am and lasted all day! The high was 53.

So the accuracy of my forecasts during this winter weather period was a pleasant surprise. Forecasting snow in Portland can be very challenging. The Report overall was interesting to see. There is plenty of room for improvement in the temperature area obviously. Conditions are my strength and I expect to see that continue. I hope the Report doesn't sway your opinion of where you get your forecast. But check back each month to see if and how I improve as the year continues!

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