Wednesday, March 10, 2010

Mike Hoffman's 16 Day Forecast

I like Mike Hoffman and enjoy watching his weather forecasts on Channel 16 (WNDU in South Bend, Indiana.) However, his "16 Day Outlook" consistently forecasts temperatures that are well below what the temperatures end-up being. Here is an example from earlier in 2010:




Feb. 20: Forecast high = 34º Actual high = 35º, 1 degree below actual


Feb. 21: Forecast high = 34º Actual high = 39º, 5 degrees low actual

Feb. 22: Forecast high = 30º Actual high = 33º, 3 degrees low actual

Feb. 23: Forecast high = 28º Actual high = 35º, 7 degrees low actual

Feb. 24: Forecast high = 21º Actual high = 27º, 6 degrees low actual

Feb. 25: Forecast high = 18º Actual high = 29º, 11 degrees low actual

Feb. 26: Forecast high = 18º Actual high = 30º, 12 degrees low actual

Feb. 27: Forecast high = 22º Actual high = 34º, 12 degrees low actual

Feb. 28: Forecast high = 25º Actual high = 36º, 9 degrees low actual

Mar. 1: Forecast high = 28º Actual high = 38º, 10 degrees low actual

Mar. 2: Forecast high = 26º Actual high = 38º, 12 degrees low actual

Mar. 3: Forecast high = 28º Actual high = 38º, 10 degrees low actual

Mar. 4: Forecast high = 28º Actual high = 40º, 12 degrees low actual

Mar. 5: Forecast high = 23º Actual high = 41º, 18 degrees low actual

Mar. 6: Forecast high = 20º Actual high = 46º, 26 degrees low actual

Mar. 7: Forecast high = 20º Actual high = 50º, 30 degrees low actual

That's an average prediction of 11.5 degrees below the actual high temperature!

I'm not a meteorologist, but forecasting a temperature over 20 degrees below normal over two weeks in advance CANNOT be good for a weatherman's chances at improving his credibility. From my amateur observations, temperature departures-from-normal of over 20 degrees are relatively rare and pretty extreme when they happen.

3 comments:

joe b said...

I think an interesting statistical analysis would be to compare long range forecasts by weathermen vs. the farmers almanac.

they both arent very good yet people refer to their validity.

jb

David said...

This has always driven me nuts about WNDU as well. I was actually astounded when I ran across this. I stopped looking at the 16-day because it's always a) depressing, and b) the cold weather almost never pans out.

ThisIsMyLife said...

i'm quite dissappointed that this is still your last blog!...you act like you're busy or something! :)