Forecast of the Day • A National Weather Forecasting Contest
Tuesday March 24, 2020
Assignment: Predict the 24 hr minimum temperature (deg F) for Saranac Lake, NY (KSLK)
On Sunday morning the low temperature in Saranac Lake, New York ("The Capital of the Adirondacks") was only 3 F. But the forecasts for Tuesday are much warmer, in the 20's, about 5-10 F above average. So let's predict Tuesday's Tmin and see what happens.
Question: What is expected to be the big difference that will make Tuesday's minimum temperature so much warmer?
What Happened?
Look at the observations to see that on Monday night and Tuesday morning, the temperature only fell to 28 F because the skies stayed cloudy all night, with occasional snow showers. That shows the big difference between clear skies and calm winds (which produced the very cold 3 F night on Sunday morning) and overcast skies. The cloud cover blocks the outgoing longwave radiation emitted by the earth and re-radiates it back to the ground, keeping the temperatures up.
As it turns out, the 24-hr low temperature dropped much more at the very end of the day, because the cloud cover suddenly cleared out, allowing strong radiative cooling for at least a while. So this was a tough forecast challenge!
| Forecaster | Tmin, deg F (error) | Comment | Day Score |
|---|---|---|---|
| OBSERVED | 13 | Tmin FINAL. | |
| 1. Alex15 | 12.5 (-0.5) | 3.4 | |
| 2. Lizzie15 | 12 (-1) | 3.4 | |
| 2. Anna15 | 12 (-1) | 3.4 | |
| 4. Joscelyn15 | 15 (2) | 3.2 | |
| 4. Autumn15 | 11 (-2) | 3.2 | |
| 6. Dorothy15 | 10 (-3) | 3.0 | |
| 7. Gus15 | 16.2 (3.2) | 3.0 | |
| CLIMATE | 16.2 (3.2) | NCDC Climate Normals, 1981-2010 | 3.0 |
| PERSISTENCE | 17 (4) | 2.8 | |
| 8. Hannah15 | 17 (4) | 2.8 | |
| 8. Leah15 | 17 (4) | 2.8 | |
| GFS-MOS-00-DAY00 | 19 (6) | 2.5 | |
| NAM-MOS-00-DAY00 | 19 (6) | 2.5 | |
| GFS-MOS-18-DAY01 | 20 (7) | 2.3 | |
| GFS-MOS-12-DAY01 | 20 (7) | 2.3 | |
| 10. EmilyS15 | 21 (8) | 2.1 | |
| GFS-MOS-06-DAY01 | 21 (8) | 2.1 | |
| NAM-MOS-00-DAY01 | 21 (8) | 2.1 | |
| 11. Keith15 | 22 (9) | 2.0 | |
| 11. EmilyV15 | 22 (9) | 2.0 | |
| NAM-MOS-12-DAY01 | 22 (9) | 2.0 | |
| GFS-MOS-00-DAY01 | 22 (9) | 2.0 | |
| 13. Josh15 | 23 (10) | The difference I think is that The minimum temperature will go up because the snow system will be moving out. | 1.8 |
| NAM-MOS-12-DAY02 | 23 (10) | 1.8 | |
| 14. Django15 | 24 (11) | 1.6 | |
| 15. Elizabeth15 | 25 (12) | 1.4 | |
| GFS-MOS-18-DAY02 | 25 (12) | 1.4 | |
| GFS-MOS-12-DAY02 | 25 (12) | 1.4 | |
| 16. Hailey15 | 25.6 (12.6) | 1.3 | |
| 17. Grace15 | 26 (13) | Sunny or partly cloudy weather becomes more frequent so maybe there is going to be more of a warm front moving in. | 1.3 |
| GFS-MOS-06-DAY02 | 26 (13) | 1.3 | |
| 18. ashleigh15 | 28 (15) | 0.9 | |
| 18. Shyann15 | 28 (15) | 0.9 | |
| 20. Miles15 | 30 (17) | 0.6 | |
| 21. Jasper15 | 39 (26) | 0 | |
| 21. Shelby15 | 35 (22) | 0 |