We May Be In For a Snowy Saturday
While snowfall from Wednesday’s clipper system was limited to the southern half of New Jersey, a weekend storm looks to bring rain and accumulating snow to the entire state.
Yesterday's Alberta clipper system dropped upwards of 4 inches of snow on South Jersey, while the northern half of the state experienced little to no snowfall. As the storm departs, snow showers will taper off early this morning and skies will begin to clear.
We will get to enjoy exactly two quiet days between storm systems. Both today and tomorrow will feature partly to mostly sunny skies, relatively light winds, and near-normal temperatures, with highs both days around 40 degrees. Areas with fresh snow cover from yesterday’s storm may very well end up a few degrees colder today, tonight, and tomorrow as the snow helps to keep the air extra-cool.
It is clear that our atmosphere has transitioned to a more active pattern overall. We’re now in the middle of a series of storm systems, each of which has the chance to bring accumulating snow to at least part of New Jersey.
The next system is scheduled to arrive early Saturday morning (starting about 1am), and looks to bring snow and rain to New Jersey for about the entire day (through at least the evening). Here’s a breakdown of my latest thinking about this storm:
Storm Track: Compared to yesterday, the new model runs take the center of the storm further out to sea. This means we are less likely to see the heavier precipitation bands from this storm. I’m a bit surprised how well the 00Z GFS, NAM, and Euro models agree on the location and strength of the storm by Saturday night… but that gives decent confidence that the forecast storm track is not likely to change much.
Moisture: This is a coastal storm. Therefore, unlike Wednesday’s clipper system, Saturday’s storm will have plenty of moisture to work with as it slides up the coast. That would lend to some healthy rain and snow totals… at the moment, total QPF (Quantitative Precipitation Forecast, i.e. total liquid precipitation) could be as high as an inch in New Jersey.
Temperatures: An accurate temperature forecast will be key to forecasting the exact impacts of this storm. Temperatures are expected to be below freezing early Saturday morning as the storm first begins. Through the middle of the day, high temperatures are forecast to reach about 40 degrees, so we should see a period from late morning to mid afternoon of just rain. And then, as temperatures drop again, we’ll transition back to snow. That final snow period will be when any snow accumulation occurs.
Snow Accumulation: This storm is expected to have wide impacts across the entire eastern US, ranging from snow to rain. The challenge for determining a snow total forecast for New Jersey will be determining the logistics of the midday transition to rain. How much snow will accumulate early in the day, before the potential transition from snow to rain? How quickly will the snow will start to accumulate again as temperatures drop and the precipitation turns back to snow? Will the storm move at the current forecast speed, which would sustain precipitation through at least midnight on Saturday night? Maybe.
So... First crack at a snow forecast? Widespread 2 to 4 inches across most of the state. The exceptions would be North Jersey and the Jersey Shore, which I would currently put in the 1 to 2 inch range.
We will, as always, keep an eagle eye on the forecast, and will have much more later today and tomorrow (including a detailed snow forecast map).