Forecast of the Day • A National Weather Forecasting Contest
Tuesday April 7, 2020
Assignment: Predict the 24 hr maximum temperature (deg F) for Las Vegas-McCarran, NV (KLAS)
An upper level low pressure center is expected to move very slowly eastward in the next couple of days, bringing significant rainfall to Southern California and Nevada. Temperature forecasts for Las Vegas, Nevada are about 10-20 F cooler than average. So let's forecast Tmax for Las Vegas.
Question: Why do you think that the GFS forecasts are cooler than the NAM forecasts?
What Happened?
The early runs of the GFS predicted more rainfall, and so also lower temperatures. But later GFS runs shifted to agree with the NAM, with less precip and the chance for warming into the 60's. The obs show that they had a little light rain in the middle of the day, but then partial clearing, and it was able to warm to 65 F.
| Forecaster | Tmax, deg F (error) | Comment | Day Score |
|---|---|---|---|
| OBSERVED | 65 | Tmax FINAL. | |
| 1. Jasper15 | 65 (0) | 3.2 | |
| GFS-MOS-00-DAY00 | 66 (1) | 3.0 | |
| 2. T-Dawg15 | 66 (1) | 3.0 | |
| NAM-MOS-00-DAY01 | 64 (-1) | 3.0 | |
| GFS-MOS-18-DAY01 | 63 (-2) | 2.7 | |
| NAM-MOS-12-DAY02 | 67 (2) | 2.7 | |
| PERSISTENCE | 68 (3) | 2.5 | |
| 3. kendra15 | 62 (-3) | 2.5 | |
| NAM-MOS-00-DAY00 | 69 (4) | 2.3 | |
| 4. Hailey15 | 70 (5) | 2.1 | |
| GFS-MOS-12-DAY01 | 60 (-5) | 2.1 | |
| 4. Keith15 | 60 (-5) | 2.1 | |
| GFS-MOS-06-DAY02 | 59 (-6) | 1.9 | |
| 6. Leah15 | 58 (-7) | 1.7 | |
| GFS-MOS-06-DAY01 | 56 (-9) | 1.2 | |
| GFS-MOS-00-DAY01 | 56 (-9) | 1.2 | |
| GFS-MOS-12-DAY02 | 56 (-9) | 1.2 | |
| CLIMATE | 75.6 (10.6) | NCDC Climate Normals, 1981-2010 | 0.9 |
| 7. Lizzie15 | 45 (-20) | 0 |