•Most guidance now agrees that the heavier snow associated with an approaching storm will remain south of our region, this means the only snow that falls across the HV will be associated with the passing frontal boundary on Sunday, and not the main storm
•Snow showers and light snow develop Sunday afternoon into Sunday evening as a cold front passes through the region, this will cause 1-3 inches of snow to fall during the day on Sunday across the region and taper off tomorrow evening
•Some of the southern most zones may be brushed by the northern fringe of the precipitation from the storm passing to our south, this may result in snow linger later in these zones, and slightly more accumulation (see zone map)
•All but one forecast model keep the moderate to heavy snow to our south, the NAM model is alone in its projections of a moderate to heavy snowfall across the HV
•Our main storm is coming ashore on the West coast today, and we will need to keep a close eye on the model guidance to ensure that there are no fluctuations in the axis of moderate to heavy snow, basically make sure that the NAM model isn’t sniffing out something before its friends.
•It will not take a very big shift in the models to increase snowfall accumulations across the region, for that reason we will need to continue to monitor the data through out the day, as of this morning this is the most realistic snowfall projections
•With the main storm passing to the South, we would no longer be expecting any snow across the region on Monday, only snow from the passing front on Sunday into Sunday Evening, the exception may be regions to the south of the dashed red line, where they may see some snow from the passing storm.
A look at the European model highlights what most models are currently showing for the upcoming storm, you can clearly see the axis of heavier snow is to our south with the region only seeing a grazing snowfall across the southern zones. The snow to the North across the mid and upper HV is not even from the storm itself, but from the passing cold front, it is important to stay vigilant when the heavier snow is only 100 miles away, and your main storm has not even come ashore on the West coast yet. This leaves a lot of room for minor shifts in the forecasted location of the heavier snow, so we will stress the importance of staying tuned for any possible shifts.
The NAM model below is the only forecast model showing a moderate to heavy snowfall across the region, while one model against 4 others is not enough to change the forecast, it certainly cannot be totally ignored, especially when our storm is still coming ashore in California. So while this is still considered an outlier scenario it is worth sharing to highlight what a small change in the track of the storm and placement of the cold front can have on our forecast.
Above the red dashed line- 1″-4″
Below the red dashed line- 2″-5″
This is the current HVW forecast for the upcoming storm, we have to follow what the majority of the data suggests and at this point write of the NAM solution, but as mentioned above we will need to keep a close eye on the trends over the day to make sure that other models do not begin to shift the storm back north and in return increase our snowfall potential.