Forecast of the Day • A National Weather Forecasting Contest
Friday March 13, 2020
Assignment: Predict the 24 hr maximum temperature (deg F) for Roswell, NM (KROW)
We show automated forecasts from the two main U.S. weather models, the Global Forecast System (GFS) and the North American Mesoscale model (NAM). Usually their forecasts for the next couple of days are fairly similar, but occasionally they diverge quite a bit. For Friday's high temperature in Roswell, New Mexico, the two models are not in agreement. So let's make our own forecast and see which model does better in this case. Question: What is the likely reason that models differ for this type of day? Roswell is famous for a past UFO incident, and it still attracts tourists from around the world.
What Happened?
Initially the GFS and NAM models were far apart on Roswell's high (from 57 to 73 F), but then they got closer. Friday turned out to be a cloudy day with some rain, but not enough to hold down the high temperature to 57 F. Instead, it climbed to 67 F, so kind of in the middle of the various forecasts. When models disagree, sometimes forecasters will choose the one they think will do better for the particular situation, but other times they choose a "consensus" (such as a simple average) of a set of different forecasts.
| Forecaster | Tmax, deg F (error) | Comment | Day Score |
|---|---|---|---|
| OBSERVED | 67 | Tmax FINAL. | |
| 1. Jasper15 | 67 (0) | sorry first one messed up | 3.3 |
| 1. Gus15 | 67 (0) | 3.3 | |
| 1. Sara15 | 67 (0) | Brings rain | 3.3 |
| CLIMATE | 67.4 (0.4) | NCDC Climate Normals, 1981-2010 | 3.2 |
| 4. Anna15 | 68 (1) | 3.1 | |
| 4. Abbygale15 | 68 (1) | 3.1 | |
| 4. Mikayleigh15 | 68 (1) | 3.1 | |
| 4. Hannah15 | 66 (-1) | 3.1 | |
| NAM-MOS-00-DAY00 | 69 (2) | 2.8 | |
| 8. Grace15 | 65 (-2) | 2.8 | |
| 8. Mathison15 | 69 (2) | 2.8 | |
| 8. Ashleigh15 | 69 (2) | 2.8 | |
| GFS-MOS-06-DAY02 | 69 (2) | 2.8 | |
| 11. Taylor15 | 70 (3) | 2.6 | |
| 11. Shyann15 | 70 (3) | 2.6 | |
| 11. Miles15 | 70 (3) | ~(0-o)~ | 2.6 |
| NAM-MOS-00-DAY01 | 70 (3) | 2.6 | |
| GFS-MOS-12-DAY01 | 71 (4) | 2.3 | |
| GFS-MOS-18-DAY01 | 71 (4) | 2.3 | |
| 14. Autumn15 | 63 (-4) | 2.3 | |
| 14. kendra15 | 71 (4) | 2.3 | |
| 14. Elizabeth15 | 71 (4) | 2.3 | |
| GFS-MOS-06-DAY01 | 71 (4) | 2.3 | |
| GFS-MOS-18-DAY02 | 71 (4) | 2.3 | |
| NAM-MOS-12-DAY01 | 72 (5) | 2.1 | |
| 17. EmilyS15 | 72 (5) | 2.1 | |
| 17. abigail15 | 72 (5) | 2.1 | |
| 17. Blake15 | 62 (-5) | 2.1 | |
| 20. Eavenly15 | 73 (6) | 1.9 | |
| 20. Alex15 | 73 (6) | My best guess, thank u! | 1.9 |
| 20. Josh15 | 73 (6) | 1.9 | |
| GFS-MOS-00-DAY01 | 73 (6) | 1.9 | |
| GFS-MOS-12-DAY02 | 73 (6) | 1.9 | |
| PERSISTENCE | 74 (7) | 1.6 | |
| 23. Emily15 | 60 (-7) | 1.6 | |
| 23. Dorothy15 | 74 (7) | 1.6 | |
| 25. T-Dawg15 | 75 (8) | 1.4 | |
| 25. EmilyV15 | 75 (8) | 1.4 | |
| 25. Django15 | 75 (8) | 1.4 | |
| 25. Gianni15 | 75 (8) | i haven't got a clue | 1.4 |
| 25. Hailey15 | 75 (8) | 1.4 | |
| 25. Shelby15 | 75 (8) | 1.4 | |
| 31. Keith15 | 76 (9) | 1.2 | |
| 31. Austin15 | 76 (9) | I guess I'm right | 1.2 |
| 31. Briley15 | 76 (9) | YEET! | 1.2 |
| 34. Joscelyn15 | 77 (10) | It's going to be rainy | 0.9 |
| NAM-MOS-12-DAY02 | 57 (-10) | 0.9 | |
| 35. Karlie15 | 54 (-13) | 0.2 | |
| 36. Lizzie15 | 45 (-22) | 0 | |
| 36. Leah15 | 50 (-17) | heavy thunderstorms | 0 |