A little storminess may develop along a cold front pressing through the region Friday night offering the next opportunity for rain and snow. Some snow accumulation cannot be ruled out but this is a particularly tricky situation to forecast.
There are a lot more questions than answers for this possible winter weather event, so it’s difficult to nail down details at this range. But here’s how, Wes Junker, our winter weather expert, sees the event unfolding:
This is another tough forecast. Precipitation will start rain during the evening with temperatures above freezing but could then transition to snow during the night. How much snow falls and accumulates will depend on the snowfall intensity and whether a heavier band sets up.
The highest snow accumulations are expected to the north and west where temperatures will be coldest but there may be more potential for heavy banding east and northeast of the city.
Right now, the best guess is for 1-3 inches in the colder suburbs and and coating to 2” in and around the city. However, if the system develops a little quicker and we get into a heavier band than amounts could be higher. Or, if no band of heavier precipitation develops, snowfall amounts could even be lighter
The reason the storm is especially difficult to forecast is because the wave of low pressure will be developing almost directly overhead. If it forms just a little earlier (to our southwest) or later (to our northeast) than forecast, that would result in higher or lower accumulation amounts.
“This is a bust waiting to happen,” Junker added.
With uncertainties this large, snowfall probabilities are best used in this situation.
No snow: 20 percent
“Car-topper” - conversational snow (up to a coating): 25 percent
Nuisance snow (up to 1 inch or so): 25 percent
Light snow (1-3 inches): 20 percent
Signficant snow (3 inches or more): 10 percent
This boils down to a 70 percent chance of 1 inch or less, and a 30 percent chance of something more.
We’ll try to sharpen forecast details further tomorrow.