2018-2019 Winter Discussion(Northern Hemisphere)

The precipitation forecast trends drier than normal for much of the CONUS, tied to the anticipated ridge-trough pattern helping to keep the Pacific jet away from the West coast, while the trough over the East imports continental polar airmasses that are relatively dry. One exception is above-normal precipitation being favored from the Gulf Coast through Mid-Atlantic, with a mean frontal zone possible here and increased storm activity possible along the baroclinic zone setting up along the eastern seaboard. While not directly implicated, this circulation could increase odds for a substantial winter storm across the major metropolitan areas in the East. Above-normal precipitation is slightly favored over the High Plains of Montana, where periods of upslope precipitation become more likely as the period progresses. Aforementioned anomalous southerly flow over southern Alaska increases the odds for above-normal precipitation there, though the panhandle is more likely to see below-normal precipitation downstream of the forecast 500-hPa ridge.