Thursday, 11:35 a.m.
2014 is off and running, and the first storm of the year is really a tale of at least two separate features, arguably three. That is splitting the available energy to the storm, resulting in somewhat limited snowfall totals compared to having one strong, large storm tracking from one place to another. Already snow has been fairly prolific from northern Illinois eastward into the southern tier of New York and the northern tier of Pennsylvania, with some places having already pick up 6 to 12 inches of the white stuff. More is on the way this afternoon into tonight, but as the upper-level trough moves from the Mississippi Valley this morning to off the East coast by midday tomorrow, there will be a steady tendency toward drying and ultimately clearing from west to east tonight into tomorrow.
I mentioned three pieces to this storm. Let's break it down to see if we can pick them all out. If you look at the latest surface pressure analysis, you can easily pick out where the surface low is right now:
Tied to this northern storm is the arctic boundary, which is depicted by the latest temperature analysis:
Basically, the boundary stretches from Boston to the Connecticut shoreline, then along Interstate 80 to near Pittsburgh to southwestern Ohio. Most of the snow over the past 24 hours has clearly been in the cold air mass north of this boundary, and it has been a pretty powdery snow at that. As the northern storm rolls eastward along this boundary this afternoon and evening, the arctic boundary will be pulled southeastward across the Ohio Valley and across northwestern Pennsylvania, pulling some of the snow farther south and east as well.
The final piece to all of this is the upper-level disturbance rounding the base of the large-scale upper-level trough. Here's the NAM 500mb forecast for this afternoon:
Bands of rain extend from the Florida Panhandle to the northern Florida Peninsula up to the northeast, including southeastern Alabama, much of Georgia and parts of the Carolinas, all tied to this upper-level trough. As the trough swings eastward, it will pop a storm off the North Carolina coast early tonight. And once that storm begins to develop, the northern low will collapse, and most all of the energy in this trough will transfer to the storm growing off the East coast. In turn, this will finish off the process of yanking all of the arctic air southeastward later tonight and tomorrow morning. In so doing, the atmosphere will be squeezed out of the atmosphere, resulting in snow.
In the mid-Atlantic, this may start out as a shower or even a period of rain, but as the cold air quickly takes over and temperatures plummet, snow will rapidly take over as the only form of precipitation.
The models have been all over the field in terms of precipitation forecasts. They're finally starting to come together now, and through tomorrow morning, this is what the 12z NAM is forecasting:
This will result in the heaviest snow along the Jersey shore up across eastern Long Island into southeastern New England. That's not to say there won't be heavier bands of snow farther north and west in the arctic air, but the former places are where you want to be if you want to see 6 to 12 inches of snow.
Once the storm passes, the arctic air will rush in, with temperatures going virtually nowhere during the day tomorrow in the mid-Atlantic into New England despite the return of sunshine from west to east. Look at the projected anomalies:
If you think that's cold (it will be), wait until early next week!
A more concentrated storm will track across the Tennessee Valley and into the Appalachians Sunday. It will pull much milder air northward up the Eastern Seaboard ahead of it, and that will mean seeing rain much of Sunday from the Southeast up into the mid-Atlantic states. There is a chance the low levels of the atmosphere remain cold enough to support some sleet and freezing rain for a time, but you will likely have to go to the Hudson Valley and northern New England for the cold to be deep enough long enough for there to be any snow on the front side of the storm.
In contrast, there will be plenty of cold air west of the track of the storm, and that means snow. There can be some some snow from northeastern Arkansas northeastward through western and northern Tennessee up across the Ohio Valley into western New York state, and the snow could be in the 4- to 8-inch range in many of these places.
The amount of snow, or ice and rain depending upon where you are, is somewhat immaterial. The cold that follows these storms is going to be severe. I won't go into the specifics yet, but the GFS anomalies continue trending colder, plain and simple. Here are the forecasts for Monday and Tuesday, respectively:
The lighter shades of pink? MORE than 30 below average! And we're essentially at the bottom of the curve, temperature wise, with maybe another 1 degree drop in the average temperature for most mid-latitude stations. That's just sick looking! It could well be the coldest of the entire winter season, and records are going to fall in the coming week.
With this being the start of the new year, many of you have made resolutions. I have more come up with goals, things to strive for, and will work on the process as a way of helping me achieve those as I try to do some crazy things to figure out where my limits are. For instance, I ran a 5K Resolution Run as part of our local First Night celebration. It's all part of my desire to stretch myself to try to run another half marathon, a full marathon, then compete in a half ironman, a 24-hour bicycle challenge, and then, finally, a full ironman. So far, I'm healthy, and I'm trusting my coach will keep me on an exercise regimen that will get me through this gauntlet of endurance activities! What might you be up for in 2014? Why not challenge yourself to do something you've never done before? Hey, they weather may be challenging records in the coming days, so maybe you could just say... 'Tis the season!
A dominant ridge will keep it hot from the Ohio Valley to the East into next week, while the disturbance north of Cuba is slow to develop as it approaches the southeastern Gulf of Mexico.
Two systems will delay the onset of warm weather in the Ohio Valley and the East over the next week or so, but then it should get warm all across the country heading into the Memorial Day weekend.
A turn to much colder air over the Northeast and mid-Atlantic states will set the stage for a rain and snow storm later this weekend before it turns much warmer later next week.
It's warm now, but will turn much colder this weekend, with a storm threat later Saturday into Sunday. Warmth will return by the second half of next week.
Though it is cold now east of the Mississippi, with a couple of opportunities for snow into the weekend, a blast of warmth is due for much of the country east of the Rockies next week.
Warm air will once again surge eastward from the Plains to the East Coast this weekend and early next week. A strong storm next Tuesday and Wednesday will then be followed by colder air later next week.