Friday, 11:30 A.M.
We have put the month of January behind us, now. The month as a whole was very cold - in the Rockies. A Great Basin high set up camp, and wouldn't budge most of the month, and any time it did, it was replaced by a deep trough that promoted overall chill throughout the West. East of the Rockies, it was a mild month overall. The core of the mild weather was across the South and Southeast, with temperatures three to as much as eight degrees above normal from Mississippi to Florida up to Virginia and Maryland. Even the area from eastern Kansas, Missouri, and southern Iowa into northern Illinois, Michigan and upstate New York saw temperatures end up a solid three degrees above normal for the month, despite the outbreak of arctic air more than a week ago.
With the last of the record warmth wiped out of New England by the passage of a cold front yesterday, the arctic air is once again well established from the northern Plains and Midwest to the mid-Atlantic and New England. The full force of it is now drilling into the East behind that little clipper system that dumped 1 to as much as 6 inches of snow across parts of Maryland, northern Virginia and Delaware into South Jersey early this morning. The highest total was 5.9 inches in Dover, Del., most of which fell in about three hours.
Look at the morning pressure and thickness analysis:
The dashed, light blue lines represent 1,000-500 mb thickness values, and the lower they are, the colder the air mass is. The thermal trough, if you will, stretches from Ontario through Michigan into Ohio. Look at the 850 mb temperature forecast this evening:
Now we're set up for a continuation of the series of relatively weak upper-level disturbances, started today that mini snowstorm in the mid-Atlantic, to parade from the northern Plains and Midwest to off the mid-Atlantic and New England coast through the first half of next week. Two are worth noting. The first of these will actually be preceded by a weak system that will deposit an inch or two of snow from southern Minnesota, southern Wisconsin and northeastern Iowa all the way to the spine of the Appalachians tonight and tomorrow. As it gives up the ghost tomorrow night crossing the mountains, the second feature comes right in behind it, and carves out a weak storm off the mid-Atlantic coast Sunday. As it deepens, and the air aloft cools, there will be some fitful bursts of snow (not as well organized as we saw this morning in the mid-Atlantic) from the mid-Atlantic coast to southern and eastern New England. While most places will not get more than an inch or two of snow, a few spots get get it the right spot and double that. It will be hard to know specifically who will get that extra bit of snow, but it's still on table.
Following that another feature darts across the Midwest to the Northeast Sunday night to Monday night with limited moisture. But the one behind that moving into the Midwest Monday night and Tuesday bears watching. It may well behave more like a true clipper system, with several inches of snow north of the track of the low. That could include portions of Minnesota, Wisconsin and Michigan to the northern mid-Atlantic and southern New England.
Once that feature exits the Northeast and mid-Atlantic later Wednesday, more and more of that mild air over the eastern Rockies and Plains will be poised to come eastward. The warmth should spread into the Ohio and Tennessee valleys with minimal resistance on Thursday, and then reach the mid-Atlantic and New England with some resistance by next weekend.
All of this, of course, is just secondary to the countdown to spring, which begins Saturday when Punxsutawney Phil exits his home and makes his annual forecast for the arrival of spring! Will he see his shadow, or will he not? We'll find out tomorrow. From a pure astronomical standpoint, we're only halfway to spring, so whether he sees his shadow or night, we'll technically have a little more than six weeks of winter to go before the vernal equinox on March 20.
I start ticking off dates to get me through the cold and sometimes snowy days of the remainder of winter. And they are as follows:
February 2 - Groundhog Day
February 5 - End of "Solar" winter (three month period with lowest sun angles)
February 11-12 - "Pitchers and Catchers report" (best one of all)
February 24 - Daytona 500 (late this year!)
March 1 - beginning of meteorological spring
March 20 - beginning of astronomical spring
April 1 - Opening Day of Baseball (don't talk to be about Sunday night or the World Baseball classic!)
That's my annual "Countdown to Spring." I've made it through the coldest month of the year. We're over 10 hours of daylight now. Average temperatures have begun to rise. It will still get cold, and it will still snow, but soon it will all be melting away into the warmer, longer days of spring!
Snow is ending in the Upper Midwest, and outside of the high ground of the Rockies and maybe the Sierra and the Cascades, snow chance are about over for most of the nation.
Record cold prevails in the East today. While the cold will quickly fade west of the Appalachians, it will be slower to modify east of the mountains, and in no place will it be warm east of the Mississippi through the Easter Weekend. However, much warmer air will start building on the Plains by early next week, and it should spread eastward later in the week.
Several waves of low pressure will challenge forecasters in the coming days and lead to potentially large busts in weather forecasts. In the end, though the warmth in the coming days will be replaced by a much colder air mass from west to east by the middle of next week.
It's getting warmer and looking and feeling more like spring across the country, but after this surge of warmth will come a blast of cold air from the past, one that can include snow from the northern and eastern Rockies to parts of the Great Lakes and even the northern Appalachians.
The upper-level trough coming through the eastern half of the country will leave tomorrow night, opening up the door to a nice, mild stretch of weather late this week into the weekend from the Plains on east.