The chart to remember, heading into the weekend, is the 12Z GFS snow depth forecast for day-13 (Dec 3rd). Unlike the over-forecasting of snow tendency of the GFS (and ECM), snow depth forecasts are conservative and (more) reliable. On Dec. 3rd the 12Z GFS projects substantial snow cover pushing southward through the Great Plains and across New England.

The latest NOAA/CPC Seasonal Drought Outlook indicates expanding drought from the Southwest U.S. across the 4-Corners region and Western Texas plus into the Mid-Atlantic region from the Southeast U.S. The Florida Peninsula is added to the developing drought forecast. Drought erosion is indicated across the northeast quadrant of Texas northeastward to the Midwest States. New England drought also eases. The Northwest U.S. drought is forecast to weaken (and end in some locations). Except for south coastal areas, drought development in California is not expected.

According to GFS, a semi-permanent upper-level longwave low-pressure trough anchors over Europe during the remainder of November causing a chilly pattern to develop also featuring heavy precipitation. At night, widespread 20’s (F) cover Europe into early December with teens (F) across Scandinavia and Northwest Russia. <32F reaches the British Isles.

La Nina suddenly displays life with notable strengthening during the past 1-2 weeks. All Nino SSTA regions are within the La Nina threshold. The catalyst to the cooler change is a consistent and strengthening positive phase of the southern oscillation index (+SOI) causing a steady increase in up-welling trade winds and shifting the global climate convincingly into a cold ENSO regime.

A wet weather shift from Argentina and more recently central continent into Central/East Brazil initiates in the 6-10-day period according to the "most likely" mega-cluster ensemble. The wetter shift should remain in-place well through early meteorological summer 2025-26 while Argentina shifts drier.