A significant ice and snow storm is likely this weekend. It has been named “Jacob” by TheWeatherChannel. Heavy snowfall accumulations are likely from this storm system, in the order of 6 to 12 inches for many parts of the Great Lakes and North East (inland). Severe ice accumulation is also possible, especially just to the south of the Lakes and near the North East coast. In some places, a switch from ice to snow and back to ice again is possible, meaning there’s a real risk of nasty traveling conditions this weekend.
The following snow accumulation chart courtesy of Pivotalweather.com shows how much snow is expected to fall between now and midday on Sunday. Notice the large, expansive area of snowfall spanning from the east of the Dakotas, through the Lakes, and into parts of the North East.
Freezing rain is also a significant hazard from this storm system. In some places, between 0.25 and 0.5 inches of ice accumulation is possible. This phenomenon occurs as rain falls within the atmosphere but the surface (ground) temperatures remain largely below freezing, meaning any rain droplets, usually supercooled, freeze upon contact with the ground. Be aware of this risk if you are traveling this weekend.
Our snowfall accumulation futurecast can be seen below. Importantly – don’t take any weather map too literally. Please use them as a rough guide.
In places that receive “pure snow”, in other words miss out on the freezing rain, drifting of snow is a real issue this weekend. For example on Saturday, when the storm will be over the Lakes and heading into the North East, wind speeds could well reach over 50mph (in gusts) over the North, meaning some large snow drifts are possible. As well as this, ice accumulation could produce power outages. A combination of strong winds and ice accumulation puts a high amount of pressure on power lines, so be aware of this risk.
As the storm system clears into Sunday, it will leave behind a very cold legacy. A bit of an Arctic blast is expected, with temperatures a bit below normal to start next week. Especially over the Lakes and North East, where lake effect snow showers are entirely possible from this storm. In fact, some significant lake effect snow accumulations are possible early next week. This following temperature anomaly map from Pivotalweather.com shows where these below average temperature anomalies are expected by Tuesday.
To summarize, Winter Storm Jacob is expected to be very active, and please prepare for the severe weather hazards expected in your area. It’s also going to be turning cold next week, so wrap up warm.