10:50 AM | ***Some snow is possible at the onset on Wednesday north of PA/MD border, but it turns into a rain event...some of the rain can get heavy...some amazing cold in China, Russia***

January 24, 2023Paul Dorian

A significant winter storm is developing today over Texas and this moisture-laden system will push northeastward over the next 24 hours bringing significant snowfall all the way from Texas to the Midwest.  In the Mid-Atlantic region, snow is likely to break out on Wednesday morning in areas to the north of the PA/MD border and there can be some minor accumulations before a changeover to rain later today as milder air surges northward along the coast.

Looking ahead, widespread colder-than-normal air is going to push into the northern and western US early next week and it’ll likely spread into the Mid-Atlantic/Northeast US by late next week.  Whether or not this change to colder-than-normal conditions is sustained in the Mid-Atlantic/Northeast US after next week will largely depend on the stubborn high pressure ridge aloft over the southwestern Atlantic/Southeast US. Elsewhere, there has been some amazing cold on the other side of the North Pole with the lowest temperature ever recorded in China on Monday and this follows some tremendous cold last week in Russia (Siberia). This frigid air is now spreading to the Korean Peninsula and on the way to Japan where there can also be some all-time low temperatures.

10:45 AM | ***Active pattern brings next storm to the Mid-Atlantic region at mid-week…accumulating snow at the onset in parts of the area***

January 23, 2023Paul Dorian

As one storm continues to impact the Mid-Atlantic region with lingering rain and snow, the seeds for the next system are rolling through the southwestern states in the form of a vigorous upper-level low. This feature will drift into Texas on Tuesday and help generate surface low pressure and abundant moisture will feed into the system from the Gulf of Mexico.  On Wednesday, this surface low pressure system will push northeastward with its large moisture field advancing to the Midwest and Mid-Atlantic. Another key player in the upcoming mid-week event will be strong high pressure that forms over southeastern Canada. This system will anchor an air mass that will be cold enough for widespread accumulating snow across the Midwest, interior Mid-Atlantic and Northeast US. There is likely to even be some accumulating snow at the onset in portions of the I-95 corridor of the Mid-Atlantic on Wednesday before the precipitation ultimately changes to plain rain.  

1:30 PM | ***Stratospheric temperature update…upcoming storm threats for the Mid-Atlantic/Northeast US***

January 19, 2023Paul Dorian

Stratospheric temperatures have risen noticeably during the past couple of weeks in parts of the polar region in the Northern Hemisphere and indications are there will be changes of location of the polar vortex 10-15 days out.  In addition, stratospheric warming looks like it could become centered right near or over the North Pole by the time we get into the early part of February. A stratospheric warming event such as this being forecasted could very well result in the displacement of cold air masses from the high latitudes into the middle latitudes sometime later in February.   

In the short term, two storm systems are on the way for the Mid-Atlantic/Northeast US in the early and middle parts of next week.  As has been the case in January, sufficient cold air for the generation of accumulating snow in the immediate I-95 corridor will be a struggle with both of these upcoming storms.  Having said that, it looks like a close call in terms of at least some snow and/or ice in the I-95 corridor during either of these storms and any small change in the overall pattern can make an important difference. Odds do favor accumulating snow in the interior, higher elevation locations of the Mid-Atlantic/Northeast US during each of these storms next week.

12:00 PM | ***Nationwide colder-than-normal conditions on the table by late next week...active pattern to bring multiple rain/snow threats to the Mid-Atlantic/Northeast US***

January 18, 2023Paul Dorian

While the western US may experience an extended quieter weather pattern beginning later this week, it’ll remain quite active across the central and eastern US.  The break in the action in the western US will be due to the development of an upper-level ridge of high pressure that will ultimately extend from the eastern Pacific Ocean northward into Alaska.  In response to this ridge, an upper-level trough of low pressure will form over the central US and Canada by later next week. The combination of the eastern Pacific-to-Alaska ridge and the trough over the central US/Canada will result in upper-level winds that can easily transport cold air masses from northern Canada into the US. In fact, signs point to widespread colder-than-normal conditions across most the nation by late next week. Nationwide colder-than-normal weather in late January is quite impressive considering this is when climatological averages are close to their lowest levels of the year.

Meanwhile, the southwestern Atlantic Ocean will feature a ridge of high pressure in coming days that will intensify at times and the corridor region between the upper-level low (cold) over the central states and the Atlantic Ocean ridge (warm) will become a “battle zone” region with multiple storms riding through it from southwest-to-northeast. Accumulating snow has been virtually non-existent so far this winter season in the immediate DC-to-Philly-to-NYC corridor, but this active pattern will at least be able to raise hope for snow lovers in that part of the country with a couple of storm systems next week.