Saturday, January 22, 2011

Grades and More Grades

TMF finally had a chance to update grades for the last three events:

1. Snow event of Jan. 17 - details here
2. 7-Day Outlook Sample - details here
3. "Coldest night of the year" forecasts - details here

Overall, cumulative grades to date can be found here

A nighttime shot of the super fluffy snow we've been getting
So what's the upshot of all this? KARE seems to be on a roll, with three consecutive As. However, it's important to note that they benefited by not participating in the 7-day outlook test (KARE does not provide forecasts beyond 5 days unless the next weekend represents days 6 and 7). Most weather outlets did not perform well in the 7-day outlook (with the notable exception of KSTP) and so KARE did not have to absorb a likely low grade for that event.

At this point, the weathercasters are bunched together with middling grades -- all have a C or C+ at this juncture.


  1. Cherry picking again, eh Bill?

    Here's a more complete comparison with each of the observation sites around the metro, and the forecasts...

    WCCO: -13
    KSTP: -15
    FOX: -19
    KARE: -14
    NWS: -17
    Star Tribune: -15
    MPR: -21
    TMF: -11

    Minneapolis/St. Paul Int'l Airport: -16
    St. Paul Holman Field: -17
    Crystal: -22
    Blaine: -20*
    Lake Elmo: -27*
    Lakeville: -29*
    Flying Cloud Airport (Shakopee): -21

    * = Coldest on-hour temperature, could have been colder between observations.

    When you consider the entire area, not just the single site of the airport a more complete picture emerges.

    I like reading this site for fun, but I really wish you'd put more rigor into your "grades". Right now it's pure entertainment and cute pictures of dogs.


  2. Thanks, Kevin. I know in the case of MPR, the prediction was specifically for the MSP airport. That's the number that's thrown around on the news and everywhere else, so I still think that makes sense to use as the measuring stick and the one that forecasters are forecasting for unless otherwise noted.

    Again, I've never laid claim to this site being definitive in any sense. How would you suggest that more rigor be added to the grading process?

  3. Hmmmm...Douglas says we get a "thaw" next week. I've looked at the long term forecasts on and they give one day next week with temps flirting with the thawing mark. Does one day equal a thaw?! I always thought a winter thaw meant that a few days of above freezing temps during the day at least.

  4. I think that's a good idea for the next poll question. We'll see what people think.

  5. "Who's crystal clear and who's all wet when it to comes to Minnesota weather forecasters?" tends to suggest that you're some sort of authority on the subject.

    As for rigor, if you've taken some science classes, you should know how to add rigor. Otherwise, might be time to do a bit of research so you can be more thorough.

    Even so, this is still an entertaining website. Keep up the good work.