A look at the current NYS radar loop may cause you to look out your window and ask “is this thing broken?”
Most locations are currently cloudy, damp and cold… with temps in the mid to upper 30s. A few locations may be seeing some light rain or light wet snow showers… but most locations are dry at the moment.
The radar tells a MUCH different story, implying that the entire region is seeing periods of light to moderate wet snow (mixing with rain in the valley). The reason for the difference is that wet snow is in fact falling from the cloud, but it is evaporating before reaching the ground (VIRGA). This phenomenon usually occurs on the front end of storms, with dry air in place… precipitation falls from the cloud, taking time for the air to fully saturate before the precipitation can reach the ground.
In this case… cold, DRY air has invaded the Hudson Valley, and undercut the warm moist air that brought us an inch or more of rainfall in some areas, over the past 24 hours. That cold, dry air has dropped temperatures, but also dramatically lowered the humidity in the low levels of the atmosphere. The result is that the radar continues to reflect areas of steady precipitation falling across the Hudson Valley and Catskills, while the surface is dry in most places because the precipitation is evaporating before reaching the ground. It’s a rather unusual situation, that we don’t see all that often… because the low level dry air arrival usually coincides with the frontal boundary pushing east more quickly. But today… this band of precipitation continues to linger a bit longer.
??LOOKING FORWARD…
So… when we talk about the next several hours of weather, we have to offer the possibility of a period of wet snow developing across portions of the region. This precipitation should gradually push to our east… but it’s very possible that before that happens… the atmosphere becomes saturated once again, and a period of wet snow falls. The best chance for this is areas further south and east… and as we approach sunset, it could result in some icy spots.
We’re not currently projecting widespread snow… or widespread accumulation… but we’ll need to monitor this VERY closely. We’re beginning to see some heavier areas of precipitation moving toward the lower Hudson Valley… so this could become an issue for the evening commute. We’ll have more updates as needed.