Wednesday, 11:55 A.M.
I'm seeing more and more people adding to the chorus of calling the winter "over" in the wake of the snowicane now lashing Cape Cod and aiming for Nova Scotia and New Brunswick. This is one nasty storm, one of the stronger ones you will ever see rolling through the Northwest Atlantic. I've been looking at observations and web cams from Nantucket Island and parts of the cape, and the images that you can make out are simply wild! Nantucket has picked up over a half foot of snow thus far, and winds have gusted just over 80 mph in two separate locations on the island. This will deepen to the point where it would be considered a Category 2 or even a Category 3 hurricane!
It is driving extraordinarily cold air all the way to the Gulf Coast and off the coast, with temperatures some 20 degrees or more below normal. Look at the morning lows:
High pressure moving into the East tonight will mean a clear, calm, cold night with record lows in much of the East, but then there will be a turnaround in temperatures starting tomorrow afternoon, particularly in the Tennessee and Ohio valleys.
A storm forming over the eastern Rockies and western Plains late tonight will head northeastward toward Wisconsin tomorrow, and I'm here to tell you the air mass north and west of the track of the storm is hardly warm. Look at the 12z March 26 NAM 850mb temperature forecast for early tomorrow afternoon:
That means it will snow north and west of the track of the storm, impacting parts of eastern South Dakota and Minnesota into northern and western Wisconsin. This is not unheard of for late March, and for most areas from Chicago on south and east, it's not a concern with this first storm.
There will be a cold front behind this storm, and some of the cold air over the northern Plains and Upper Midwest will slide southeastward behind it. It won't get very far to the south, but far enough that it may come into play when storm number two rolls around.
And by Saturday morning, that second storm will move into Kentucky. Here's the NAM forecast for Saturday morning:
And the corresponding 850 mb temperatures:
That implies it could snow in or near Chicago late Friday night into Saturday morning. And as this storm gets better organized, it will have enough cold air on the northern flank of it that snow is a possibility across parts of Michigan and northernmost Ohio into upstate New York and northern New England later Saturday and Saturday night, then into Sunday.
And that's just the second storm. A weaker one follows into the western Great Lakes late Monday, and there may be some snow with that system in parts of the northern Plains and Upper Midwest, and perhaps across parts of upstate New York and northern New England on Tuesday. Again, it may not be outside of the normal areas where snow would typically be found in late March, but it suggests that some places a little farther south won't be far from seeing snow.
As we go into April, it wouldn't shock me to see another amplifying trough develop that would tap some of the remaining arctic air in Canada. In turn, if there's a well placed storm, I could see how it snows in places that think the snow is now over. Right now that seems like a low probability event, and the pattern overall won't be nearly as far below normal in the coming days as it has been most of 2104 to this point. Still, in the back of my mind, I'm not sure I'm ready to throw the towel in completely on winter.
Despite the current chill, warmth is becoming more certain this weekend and beyond from the Plains to the Northeast, even as Erika threatens Florida Sunday night and Monday.
While Danny has been declared an open wave, the low pressure area trailing it will likely have at least a passing impact on the weather along the East Coast next week.
It may be hot now in the Northeast, but much cooler air is drilling into the Rockies and is heading eastward. An even cooler air mass this weekend and early next week will be followed by a stronger warming trend.
The retreat of the jet stream will lead to more warmth than not in much of the country heading into the second half of August.
More concentrated areas of active weather will be the rule into the early part of next week across the country as weak storms move steadily eastward.
A building upper-level ridge over the southern Plains will escalate the heat, while diverting disturbances with showers and thunderstorms around it through the northern Plains into the Great Lakes.