There used to be a waterpark in Orlando named Wet n’ Wild. That could also describe our forecast for the next 24 hours.
A rather potent storm system is moving toward the Great Lakes, producing blizzard conditions across the Plains and Upper Midwest. Behind the storm, arctic air is plunging southward from Canada. How cold is this airmass? When the front goes through, some places have dropped 30-40 degrees in an hour. In Denver, the temperature dropped to -24 this morning, just 1 degree off of their all-time record low for December. Up in the Northwest Territories of Canada, RabbitKettle Lake dropped to -64 this morning. That’s actual temperature, not wind chill. The airmass will moderate significantly before reaching us, but some colder air is definitely on the way.
Rain will move in this evening, and could be heavy at times overnight into Friday morning. Winds will start to pick up tonight, and should really be cranking Friday morning and into the afternoon. Sustained winds of 15-30 mph are likely, with gusts in excess of 50 mph possible, especially along the coast and in the hills. With strong winds and astronomical high tides, some coastal flooding is expected, mainly with the morning high tide on Friday. The rain may taper off for a while around midday Friday, but the cold front moves in from the afternoon. Unlike most cold fronts, this one will be moving from southwest to northeast, and the colder air will come in on southwest winds, which normally brings in milder air to our area. Temperatures will rapidly drop once the front moves through, and while they won’t drop 30-40 degrees in an hour, a drop of 20-30 degrees over a couple of hours is certainly possible. A line of showers will accompany the front, and as the colder air moves in, these showers could change to snow before ending in the evening. As temperatures plunge, any surfaces that are still wet will rapidly freeze up during the evening, so keep this in mind if you’re heading out.
As the storm pulls away on Christmas Eve, an upper-level low pressure system will move into the Northeast, keeping plenty of clouds around. Winds will remain gusty as the storm system meanders around in Quebec. With much colder air in place, and gusty southwest winds moving across the relatively mild ocean, some ocean-effect snow showers are possible across the South Coast, Cape Cod, and possibly Cape Ann as well. Some accumulations are possible across Cape Cod. High pressure builds in for Christmas Day and Monday with drier and chilly conditions, with winds gradually dying down during the day on Christmas.
Thursday night: Rain developing, becoming heavy at times overnight, becoming windy. Temperatures slowly rise overnight.
Friday: Rain tapers off to showers, more rain possible late in the day, possibly changing to snow toward evening, very windy. High 50-57 in the morning, temperatures drop sharply in the afternoon.
Friday night: Partly to mostly cloudy, snow showers end in the evening for most, but may continue near the South Coast and Cape Cod, still windy and turning much colder. Low 9-16.
Christmas Eve: Intervals of clouds and sun, breezy, more snow showers possible near the South Coast and Cape Cod. High 18-25.
Saturday night: Becoming partly cloudy, some lingering snow showers possible across Cape Cod, still breezy. Low 9-16.
Christmas Day: Becoming partly to mostly sunny, breezy again. High 21-28.
Sunday night: Clear skies. Low 14-21.
Monday: Sunshine and a few clouds. High 26-33.
Storm HQ 