The 12Z GFS indicates a long-duration snowfall event along and trailing a cold front which shifts eastward slowly this week. The snow begins tomorrow night in the south/east Great Plains and stretches to the Ohio Valley and then eastward into New England for later this week. GFS grinds out 1-2 feet of snow across this large area - which is likely excessive, but the model certainly makes its point.

Traditionally, a “bomb cyclone” is a low-pressure system deepening (strengthening) by more than 24 MB over a 24-hour period. The definition usually applies to middle/upper middle latitude. Although a “bomb cyclone” is not a tropical cyclone, these systems can reach category-1 hurricane force on the Saffir Simpson Scale.

NOAA issues a Winter Storm Watch for the Mid-Atlantic/southern New England coastline. ECMWF is most aggressive with the snowfall amount forecast for New England where 10-20 in. of snow acros southeast Massachusetts is indicated. Of note, the GFS forecast is considerably lower as the storm is farther offshore.

NOAA/NWS projects significant snow along the Northeast Corridor Coast FRI/FRI night and New England/northern Mid-Atlantic region SAT/SAT night. Forecast confidence is HIGH that this storm will occur.

Stratospheric cooling is projected for the 11-15-day period across Canada indicating that the troposphere (below) will expand and warm consequently preventing a frigid 11-15-day forecast as indicated by GFS and other models to validate.

Upper ocean heat in the equatorial Pacific Ocean to the east of Dateline has diminished to near normal implying fuel to maintain La Nina is diminishing rapidly.

In the morning Climate Impact Company U.S. Energy Report, both the GFS and ECM agree on a snowstorm for east/southeast New England for early in the upcoming weekend. Southeast Massachusetts may receive 1 foot of snow.

Proximity of snow cover in the Missouri Valley coupled with a northerly air mass trajectory drove over-achieving cold mornings this weekend in Louisiana.