A few features are worth pointing out:
- The height anomalies associated with temperature extremes are generally much larger in winter; this is because the height variance is much larger in the cold season.
- The winter maps consistently identify southeast Alaska and western Canada as the focal point for an upper-level ridge that can bring extreme warmth to Fairbanks in the cold season. This flow orientation advects warm air from the south and creates downsloping (chinook) flow off the Alaska range. The pressure gradient also creates wind that disturbs the low-level inversion.
- In April through August, the axis of a heat-generating ridge is much closer to Fairbanks and in July it's located right over the Alaskan interior. This indicates that unusual heat in summer is caused less by southerly chinook winds, and more by subsidence in place under high pressure aloft.
- The heat-generating pattern for September is unusual, showing a high pressure anomaly over far northwestern Canada. More investigation would be required to explain this.
- The wintertime cold pattern is not simply the inverse of the warm pattern: the trough axis is located closer to Fairbanks than the ridge in the warm composites, and there is a tendency for strong ridging over the Bering Sea in the cold events. These features reflect the optimal configuration to bring a cold airmass to Fairbanks along with surface high pressure and calm winds.
- The warm season cold composites emphasize a trough over the interior or North Slope of Alaska, which would be associated with both a cold airmass and an abundance of cloud and precipitation in Fairbanks.