Thursday 10 a.m.
A low pressure area will develop west of the Great Lakes tonight, then elongate north to south tomorrow as it moves into the Middle Atlantic states. So far, it does not look like it will consolidate into a strong storm until it is well off the East Coast on Saturday. This leaves us with the prospect of a system that will cause snow over a large area, but which may not deliver more than an inch or two in much of the affected areas. Usually with such storms we wind up with some hot spots where accumulations are greater than expected (of course the way I worded that leaves much to the imagination). Here is the preliminary snow map from this morning:
Once the storm leaves, another cold high pressure area will move into the Northeast for the weekend. However, the computer models have consistently shown a switch to southwesterly flow aloft early next week. If correct, a place like Philadelphia could have a high temperature of 40 on Monday, 50 on Tuesday and even higher on Wednesday. Cold air should return by the end of the week, but at least for a while, the river of Arctic air will be flowing somewhere else.
In my quest to find ways of succinctly distilling wide-ranging thoughts into concise, quick prose, here is my description of the current situation in the Northeast. (Fortunately for my Twitter followers on accuElliot, I cannot turn this description into a tweet.)
Today: Sharp blasts of face-freezing breezings, thumb-numbing bitter blusters with the low winter sun a hapless bystander who gives up in disgust after around 5 p.m. The feeble sun can do little to stem the freezer-full of air from the arctic snowfields when the Hudson Bay wind tunnel is open. We're certainly be in winter's kingdom this week.
We are in a time when cold and wind are constant companions; times when barren tree limbs snap brittly in the unforgiving blusters of winter's dim domain... the cold night ahead of us with the melancholy moon stands silent sentinel over the frozen ground. Icy needles of wind are marauding through the Midwest, whistling through Wisconsin, irritating Illinois, icing Iowa and mesmerizing Michigan. Now, too, the cold penetrates Pennsylvania, nips New Jersey, cools Connecticut, rushes through Rhode Island, marches through Massachusetts and Maryland, dashes through Delaware and torques through New York (not to mention vaulting into Vermont, turning temperatures negative in New Hampshire and minusing Maine).
As we feel the chill driving us to January's gelid jailhouse, our thoughts might wander to spring. One day, some day, the sun will coax us back toward milder times. One day, some day, the cautious crocus and daring daffodil will show their bright flowers to the first tender warm breezes.
But those times will seem all too remote and inaccessible the next few days, with mornings for the mittens and scarves, parkas and hoods, a wintry wakeup inside the gates of January's jailhouse. We were late to reach the great gulf of winter, but its uncharted waters of cold waves loom larger this morning, the ice water plenty deep.
We are in the midst of a classic, bitterly cold, ice-bound day of winter, when face freezing winds run rampant across the winterscape as the sun is just a feeble bystander an eternity away.
Here is one snapshot from this morning's NAM run, depicting the precipitation it predicts for Saturday between 1 and 7 p.m. ET. The rain/snow line should be close to the Pennsylvania-Maryland border.
it appears a storm will form the Southeast and trek toward eastern New England this weekend. Current models suggest this will turn into a mostly rain event in the I-95 corridor...
This map shows a draft of our starting time lines and expected accumulation from tomorrow's quick-moving East Coast storm.
A storm that has brought hardship and danger to parts of Texas and Arkansas with an assortment of ice and snow will send a swath of snow northeastward today and tonight. Here is a map showing our overall estimates as of 10 a.m. ET:
That could lead to tough travel at the end of the weekend. This map for Sunday at 7 p.m. ET shows where those troubles could be (north of the line with the label "snow rain line.")
This table shows the ensemble means for the next two weeks at Philadelphia: It suggests that whereas it does turn cold, any snowfall looks quite limited.