As always, we put out outlooks with specific numbers that can be scored, and grade ourselves at the end. There are a lot of seasonal outlooks floating around these days, but you will find very few who hold themselves accountable when the season ends — especially if they did poorly.
In short, we did quite well this summer. While there was a bit of a spread in temperatures across the three airports, Reagan National, Dulles and BWI, we always make the forecast and grade it based on what happened at National, which Washington, D.C., official weather monitoring station. Our outlooks are made specifically National, and its biases are accounted for when formulating numbers. Whether we should change the way we do our outlooks to account for a broader area is a good question, but one to address another time. Having said that, here is what we got right and what we got wrong.
Our overall temperature prediction for the summer was around 1 degree above normal. We got really close. The average temperature this summer was 1.6 degrees above normal.
Our individual monthly temperature predictions were more of a mixed bag. We did decent in June, even if a bit too cold, as our call was for 1 to 2 degrees above normal, and June finished 2.9 degrees above normal. July was a near bulls-eye as we predicted a 2-degree above normal month and it finished 1.7 degrees above normal. August was a moderate miss, though we were correct in predicting it to be the coolest of the three months. We predicted August to finish 1 degree below normal and it finished 1.2 degrees above normal.
We place slightly less emphasis on precipitation, but in that area we did poorly, predicting normal precipitation (around 10-11 inches) and ending up with over 18 inches thanks to an extremely wet June.
We also predicted one 100 degree day and we didn’t have any. Not a forecast-breaker. We ended up with 38 90-degree days (for the period spanning June to August) versus our prediction of 28-34, which is an “okay” forecast, just on the low end. Not great, but not bad. Additionally, we called for a 90-degree streak of 8-10 days and we had an impressive streak of 13 days at the end of July into early August.
Overall, I would grade our outlook a B/B+. On our most important aspect, seasonal temperatures, we were within a degree of our prediction, and did well to very well on two of the three months. August was a miss, and our other secondary predictions were not great, which brings our grade down slightly from what otherwise would be a B+/A-.
Hopefully we settle into a sustained fall pattern soon. I can’t speak for everyone, but I enjoy average highs in the 70s (60s starting in mid-October), with some crisper nights. We aren’t committed to any preliminary winter thoughts yet, but with a strong El Niño possible through winter, our typically tough outlook will be no easier. But let’s enjoy autumn first!