See below for update
Jonas, (and no, I do not condone naming of storms that are not tropical cyclones) is going to do bad things to the US East Coast and hinterland.
Imma let you get back to setting your hair on fire over this storm, but first I want to 'splain something to you.
A big No'reaster like this is a big swirling fast moving low pressure system that is drawing potentially huge quantities of moisture off of a global warming and El Niño over-heated Atlantic ocean, driving that moisture inland where it will mix with cold air and turn into various forms of liquid and non-liquid precipitation.
Predicting where rain, sleet, freezing rain, or snow will fall, and how much, in such a storm is probably one of the hardest things to predict in weather. Even if the center of the storm's track is accurately predicted, and the overall size of the storm is accurately predicted, values of actual precip will not be known until it is known from direct measurements after the fact.
Also, people will get this wrong, and some will use that wrongness for evil purposes. Remember when the Great New England Blizzard of 2015 (almost exactly one year ago, and it too had a name but I forgot it) was predicted to hammer New York City and didn't? Climate science deniers and other morons went apoplectic over that. But what really happened is that a storm larger than most countries arrived as predicted, dropped about the amount of precip as predicted, but was about 10% offset to the North, sparing the greater New York City area, with it's New York Ideals and all, from any major snowfall. In other words, that storm was actually very accurately predicted, but because one tiny bit of the landscape that happened to be occupied by 20 million people got several inches less than expected, the science of meteorology was declared dead by the usual nefarious anti-science yahoos. (See this for an account of that.)
Paul Douglas, who is my go-to source for sane commentary about big storms like this, suggests that there will be more rain and mixed precip east of I-95, and more snow west of I-95, and that travel and power and such are likely to be affected. This storm, like most Nor'easters, will be windy, and that may be the biggest problem for may in its path. That wind could also be a problem in coastal areas where winds can cause flooding.
The heaviest snow may fall north and west of DC and Baltimore, and there may be some places, here and there, that will have something close to 24 inches. New York City and Boston could get decent snowfalls as well, with New York likely to get more, Boston being spared more than the usual annoying few inches. But, again, the exact distribution of snow depends on the highly unpredictable mixture of moist air coming off the ocean and cold continental air turning rain to white matter.
So, if you live in Virgina, West Virgina, Pennsylvania, New Jersey, near New York City or the Southern Tier, keep an eye on the weather, you might anywhere from just under a foot to much more. This is all going to happen from Friday into the weekend.
It is not clear that Senator "Science is a hoax" Inhofe will have ready access to Global Warming Alarmist Killing Snowballs this time around.
As Jonas T. Storm approaches, weather forecasters are tightening up their predictions. There is now a blizzard watch (not warning, watch, not as certain as a warning) for Washington DC. This is the first blizzard watch for that location since 1986.
The 1-2 foot snowstorm region at present, according to well accepted models, now includes Washington DC and Philadelphia. It is possible that this amount of snowfall will extend to New York City. The heaviest snowfall may be in DC for Friday evening rush hour. Meanwhile, Boston is not likely to receive too much snow.
From Friday night through much of the day Sunday you might expect transportation systems including by air and by land to be seriously impacted in that region.
It is still the case that the most snow will likely fall west of the I-95 corridor, with perhaps 3 feet in areas on the Piedmont in western Virginia. But, again, these things are very hard to predict. If you live anywhere from a triangle running from Louisville/Cincinnati to New York and down to Asheville/Knoxville you are likely to see snowfall ranging from several inches to a foot or so, and in some areas more, according to NOAA.
Multiple models are putting more than 20 inches right on DC with more than 30 inches along the Virginia/West Virginia border. Again, your actual mileage will vary.
Meanwhile, the wind predictions are still indicating severe conditions, with winds over 35 mph all along the coast from the Chesapeake up through Gloucester, and a concentration of 50 mph winds offshore of Long Island and on the Delmarva coast.
But again, if you are on the edge of the predicted Great Blob of Snow and not much happens at your house, realize that this is a rough prediction, and don't come complaining. Just be happy you dodged the bullet.
The biggest uncertainty is probably how far north (up to and beyond New York City) significant snow will fall. Also, all the areas near water, such as DC, New York, and Boston are probably harder to predict because interactions with the ocean may cause warmer conditions, more rain or wet snow instead of fluffy snow, etc.
The sea surface temperatures in the Atlantic are very high, and this is contributing significantly to the amount of precipitation this storm will bring. Notice the very high temps right where extra warm water would be feeding into this storm (hat tip, Paul Douglas):
The sea surface temperatures in the Atlantic have been very high in this region for a long time now, since before El Niño started, though it is likely that El Niño has contributed to this a bit.
This snowball proves bacon.
I already canceled a trip to PA this weekend. Now I'm going to stock up on toilet paper, chips and beer.
A couple of my east coast friends were complaining about the lack of a winter this year (through December). I knew that was temporary. I'm not an expert, but it seems to me with that huge area of really warm water off the coast, you either get abnormally warm weather (when the polar vortex is bottling the cold up north) or abnormally snowy weather (when the polar vortex breaks down).
BTW (spoiler alert: pedantry ahead), it's nor'easter, since "th" are the removed letters. I think "noreaster" is also OK, although my spell check is flagging it. Also, "its" has no apostrophe unless it's standing in for "it is".
Go here for the latest post on Jonas: http://scienceblogs.com/gregladen/2016/01/21/moreeaster-jonas-looks-lik…
Where did you get that first map? Who made it?
I guess the clue is in the illustration NCEP.
Cue Inhofe wheeling in a snowman next time he performs.
A denialist on YouTube has already used the Jonas storm and its "ice" as an argument against human-caused warming of Earth.... and against the not pale enough USA president..... and the storm isn't even here yet. Good grief. I made a reply video. :-)