Warm Great Lakes + Arctic Air = Immense Lake-effect Snows!
12/01/2024, 8:13 am EST
Once Again, CFS V2 Bounces Higher with Jan. 3-9 U.S. HDD Forecast
12/04/2024, 8:59 am EST
Highlight: Warm medium range forecasts according to the 12Z GFS.
Fig. 1: Stratospheric temperatures according to GFS in 384 hours (16 days) indicate a cold regime over the North Pole while warming occurs in Asia.
Discussion: In 16 days (Dec. 18) the GFS indicates a very cold stratosphere in the polar region (Fig. 1). A classic stratospheric warming event causing mid-latitude arctic air outbreaks would be just the opposite of the forecast. There is some stratospheric warming across Asia in 16 days possibly inspiring some arctic air across parts of Russia to Tibet. The 12Z GFS is quite warm across North America as the cold of this week has completely eroded (Fig. 2-3).
Fig. 2-3: The 12Z GFS medium range temperature anomaly forecast.
| HDD EIA End Date | Forecast | 12-Hour Change | 24-Hour Change | 30-Year Normal | 10-Year Normal |
| 12/5 | 198.7 | +2.1 | +3.0 | 167.8 | 159.1 |
| 12/12 | 164.9 | +1.6 | -24.5 | 180.7 | 167.3 |
| 12/19 | 160.6 | -3.8 | -12.3 | 191.0 | 175.5 |
Table 1: The 12Z GFS U.S. gas population weight HDD forecast compared to 12 and 24 hours ago.