It’s Raining Weather Temperatures All Over the Place
After a week of measuring data, I came to a conclusion that was both unsurprising and shocking at the same time. To explain, I didn’t find it surprising that the weathermen were pretty dramatically off. I mean, that was the whole point of watching the temperatures. I did find it surprising just how far they were off sometimes. (although, I’d like to note that a lot of the inaccuracy is based on the use of confusing graphics, it’s not helpful to have to interpret a table in the ten seconds they leave it on a screen if the information is not organized well…)
If you want to see the charts, here are the highs and lows. The white line is actual temperature.
Here’s an easier to understand breakdown:
High temperature difference:
WTHR: 25
WISH: 14 (one day missing from report)
FOX: 36
Dashboard: 56
WeatherChannel: 23
Low temperature difference:
WTHR: 21
WISH: 22 (one day missing from report)
FOX: 47
Dashboard: 43
Weather Channel: 39
Total degrees off in a five-day period:
WTHR: 46
WISH: 36 (four days)
FOX: 83
Dashboard: 56
WeatherChannel: 62
Of course, pure numbers don’t mean everything. Looking at the graphs, WTHR was regularly off, but was the most even distribution of inaccuracy with WISH. Fox was clearly the most inaccurate, pretty much across the board. Dashboard was the closest most often, with only two outliers really making it seem so inaccurate (24, 11 vs. 0, 0, 1, 2, 2) And the WeaterChannel was kind of all over the place in terms of accuracy. So here is my rating:
1. Dashboard
2. WTHR/WISH
3. WeatherChannel
4. Fox59
Hopefully this was insightful, colorful, and fun.
Measuring Accuracy in the Weather
Living in Indianapolis, I’d be willing to say that we have some of the most unusual, unpredictable weather patterns around. We seem to sit within the 50 mile gap that the jet stream likes to ride, sometimes it goes just above, sometimes just a bit below. Whichever it chooses, however, we see dramatically different weather that you can expect within 25 miles north or south.
To illustrate my point, I look back to college. I went to Anderson University, which is within that range north of Indianapolis (It’s 26 miles from Indy, but not 26 straight north) Junior year we got between 6 and 8 inches of snow, while my parents got rain in Indy. The year before, I enjoyed a rainy Christmas in Indy, and then returned to a blacked-out Anderson that had the ice storm of the century. And then there are other occasions where we just barely get hit by really severe weather. It’s like it always goes just far enough to hit Indy, while sparing all of the southward areas.
Lately, however, the weathermen in the local area have gotten a bit…. willy-nilly. To say the least. We were supposed to get 1-3 inches of snow in the metro area on Monday. Well, it passed with a little bit of rain and a couple of very light flurries, but Tuesday was a sure thing. Okay, maybe Tuesday night. Well, let’s go for Wednesday. Yes, that’s it! And here we are after days of predicting accumulating snow and we have about half an inch (which is apparently a lot for Indianapolis drivers…. it took me an hour to make a 25 minute drive this morning)
So, in honor of our local weathermen, I’m providing a chance for them to redeem our trust and for the rest of us to enjoy a statistical show. For the next week I’m going to find and measure the accuracy of the weather reports put out today, and find out just how accurate the weather really is. For the test I’ll be keeping an eye on WTHR, WISH, FOX59, and the WeatherChannel as well as my Mac Dashboard reading. Maybe if I have time and you get lucky I’ll make it an interactive example!
And since this is a design blog, take note of how dramatically different they all render their online weather reports. I’ll write next about that, but I wanted to do the accuracy check first since it will take time and commitment to work on. And, for good measure, scroll to the bottom for a comparison chart of their predictions, it’s amusing.
For today, however, here are the forecasts:
WTHR
WISH
FOX 59
WeatherChannel
Dashboard
