As Hurricane Epsilon makes waves in the Atlantic Ocean, winter has made its presence felt across much of the United States. Very cold temperatures for this time of year are forecast to persist over the Midwest and Northeast for much of the week thanks to a trough in the upper level flow.
Light snow is currently falling over southern New England and should amount to a couple of inches when all is said and done. This little snow-maker is a prelude of things to come on Monday night and Tuesday for that region. If you haven't heard, a large Nor'easter could potentially dump moderate amounts of snow over chilly southern New England.
The ever-changeable forecast models continue to do what they do best a couple of days in advance of a large weather-maker. The GFS global model (Global Forecast System) indicated last night that this low pressure area would cross over the 40/70 benchmark. The 12Z run of the GFS is waaaay out to sea with this low and southern New England would barely get flurries with this system. However, the NAM (North American Mesoscale Model) is now forecasting the low to pass over the benchmark and provide significant snows. Yesterday, the NAM was forecasting the low to be out to sea. The MM5, which is a smaller and research-based mesoscale model, indicates that the low will pass within the benchmark.
NAM QPF (quantitative precipitation forecast) shows that southern New England could get between 0.5 and 1.0 inches of liquid. With cold temperatures over this region we can expect solid to liquid ratios of between 10:1 near coastal regions and 15:1 over southern New Hampshire. This would provide the region with 6-12 inches of snow.
Unfortunately, most broadcast weather forecasters are "model-huggers" and will likely forecast whatever the latest model run indicates so many people have heard a variety of forecast over the past couple of days in the Northeast. The best forecast for now is to stick with the mesoscale models (since we are inside 2 days) and to prepare for a moderate snow event.