The WeatherBell Anayltics Forecast Comptetition is a monthly average temperature anomaly forecast for the next calendar month for a list of a seasonally selected cities:

Winter Cities (October to April):

Summer Cities (May-September):

Climatological Normals Data can be found here:

Between the 15th and 21st of each month, forecasters will enter their temperature anomaly forecast in tenths of a degree Fahrenheit (°F) for the next calendar month for all of the cities indicated on the forecast entry map. The forecast portal will open at Midnight Eastern Time (EST or EDT) on the 15th of the month and the portal will close at 11:59 p.m. Eastern Time (EST or EDT) on the 21st of the month. Failure to enter a forecast in time for all of the cities will result in disqualification for that particular forecast month.

A tabulation of the running scoring will commence on the second day of the month and close on the first day of the following month. All departures from normal will be taken off of the CF6 data, an example of which can be located here:

Standings will be updated daily and reference the entrant’s WeatherBell Username. Departures from normal will be based on the National Weather Service F-6 climate forms. The official error score will be the aggregate score as computed from the entrant’s forecast and the actual reported temperature anomaly (the sum of the absolute errors). The lower the error, the better the entrant’s position in the standings

The final standings, and any related prizes, shall be based on the F-6 forms as they appear on the 2nd day of the following calendar month. Should data for an individual weather station be missing or incomplete as of the 2nd day of the following month, the city may be eliminated if there are more than 5 days missing. If the integrity of the data is deemed to be questionable or unreliable by WeatherBell Analytics, WeatherBell Analytics reserves the right to remove the city/station from the scoring computation. All decisions involving data integrity and all declarations of the winner as of the 2nd day of the following month are final and the sole judgment of WeatherBell Analytics, even if there are subsequent changes to the official data.

WeatherBell Analytics reserves the right to change the forecast rules pertaining to the next forecast month at any time prior to the entry portal opening for the next month.

The winning forecaster each month will have the opportunity to consent to have their username and/or real name, approved photograph, and approved short biography (including a link to their LinkedIn profile) published on the forecasting competition website from the 5th of the following month until the end of that same month provided the information is received by the end of the day on the 2nd of the following month. WeatherBell Analytics reserves the right to wait at least 72 hours after the information is submitted to publish the information. For example, the winner of the March forecast will be declared on April 2. Upon being contacted, the winner of the March forecast can submit their username and/or real name, approved photograph, and an approved short biography to appear on the forecasting competition website from April 5 until April 30, provided that the information is received in time.

Beginning no earlier than the January 2024 forecast month, WeatherBell Analytics may begin offering prize money for the first-place winner each month. The prize money for that month will be indicated on the Forecast Competition website. Should the winning forecaster be an employee of WeatherBell Analytics, no prize money will be distributed for the competition pertaining to that month. Starting with the first competition for which prize money is offered and all subsequent months, forecasters will have to register separately for the Forecast Competition. It will be open to U.S. residents only.

Automated error scores for 30 year normals and forecast models will be displayed alongside other entrants for reference purposes only.