Interview Questions - March 2011

Seasonal Forecasts

  1. Given that the globe is warming, why does the DJF outlook favor below-average temperatures in the southeastern U. S.?
  2. I just noticed that CPC’s winter outlook, made in November, indicated above average temperatures across the Northern Plains during DJF. Instead, temperatures during the winter were colder than average. Why was CPC’s outlook wrong? How do winter “wild cards” like the AO/NAO influence a seasonal forecast? How good are CPC’s typical seasonal temperature and precipitation forecasts?
  3. The DJF precipitation outlook favored wetter-than-median conditions across the southern tier of the country because of El Niño. Which forecast tools indicated that? How does abnormally warm waters in the equatorial Pacific make it wetter than average across the southern states?

Extended-Range Forecasts

  1. I’m not sure I believe in a weather forecast made past one week. Please explain how you are able to make forecasts for 6-10 and 8-14 days. What is the process? How good are these forecasts?
  2. What is an “ensemble” and why is it better to use than individual model runs when making a forecast? How are they created and used in a climate forecast? What additional information can we get from the ensemble members?
  3. What is the Arctic Oscillation and what are the associated impacts over the United States? How does it (and other teleconnections, like the PNA) influence these forecasts?

Last modified: Tuesday, September 18, 2012, 8:38 AM