Allen...just curious...how does the NWS typically put together a "long range" precipitation forecast for the upper mid west? Expected storm tracks from the Pacific, Canada, the arctic? Historical averages/La Nina? Just interesting to me...currently the 3-4 week forecast shows above average precip for MT/ND. Thanks man!
Please keep in mind that this is kind of out of my area of expertise, but I do rub elbows with the experts on a regular basis. Anyway, my understanding is that any time you go out past about a week and even moreso as you go into 3 week, or month, or seasonal outlooks, those are long range models and statistical analysis of prior times where certain, known climate drivers, are in place or expected to be in place. And then it's pretty much left up to the team of forecasters at the Climate Prediction Center's expertise to meld the modeled results with the statistical expectations.
Things that are taken into account along with the operational models are the El Nino Southern Oscillation, Pacific Decadal Oscillation, Arctic Oscillation, the North Atlantic Oscillation to just name a few. For example, if I remember correctly a negative Arctic Oscillation has a strong tendency to bring us cold weather. So it would be expected to be negative during that period of time if they are going to forecast cooler than normal temps.
Sometimes it works well, other times I am less impressed. Kind of like playing the horses. If you bet on the one with the best odds all the time, in theory you should do well. But for some unknown reasons, betting on the favorite isn't always the winning choice in hindsight.
Note, I also don't bet on horses. Just using my understanding of it as an analogy.
