1:45 PM | Now on to the next storm…weekend coastal threat; an update on the impressive and widespread nationwide cold
Snow is winding down across the I-95 corridor from DC-to-NYC and road conditions should improve quite a bit in time for the late afternoon rush hour. Very cold and dry conditions will prevail from tonight through Friday with low temperatures in the teens in many of the northern and western suburbs of the big cities, and single digits cannot be ruled out for lows later this week in some of these locations. By the weekend, our attention will turn to the next storm and this could be a significant storm with copious amounts of moisture. Low pressure will pull out of the south-central part of the country at the end of the week and will likely consolidate into a strong storm along the Northeast US coast. While very cold weather prevails through Friday, a wintry mix along the I-95 corridor is a possibility. Stay tuned on this as there are still several days to go before the event (Saturday-into-Sunday time frame) and I believe that the forecast models will likely trend colder as the event time nears which would lead to a greater chance for snow.
In terms of how cold and snowy we have been across the nation over the past week or so, here are some interesting stats from many different locations with a focus on the western US:
• Nationwide: The nationwide average temperature of 14.8°F early Saturday morning was the 5th coldest reading since 2000. Preliminary readings suggest that the CONUS average temperature for the last 6 days was 20.8°F which is about 14 degrees below normal and the coldest since 1979 (source Ryan Maue at weatherbell.com)
• Chicago, IL: This morning featured the earliest sub-zero temperature (-6 degrees at O'Hare) in 18 years
• Philly Airport: has now received about as much snow in the past three days as in the last two winters combined
• Great Falls, MT: low temperature of -33°F this weekend was their coldest ever recorded so early in the season
• Medford, OR: record low last week of 14°F was their coldest temperature in 15 years
• Pullman, WA: Sunday morning's low of -11 degrees was the city's sixth consecutive daily record low and the earliest it has been that cold in 74 years of recordkeeping
• Denver, CO: Record low of -13°F on Wednesday smashed the old record of -5 degrees set in 2008. Thursday's low of -15°F tied the daily record and then Denver dropped to -13 degrees on Saturday morning, tying another record low
• Caspar, WY: Record low of -22°F on Wednesday smashed the old record of -11 degrees set in 1972
• Bishop, CA: recorded a record low of 8°F on Sunday morning
• Spokane, WA: the high temperature held in the teens last week for the first time since 2011
• Ely, NV: Record low of -17°F on Wednesday crushed the old record of -5 degrees. Record lows were also set on Thursday (-23°F) and Friday morning (-19°F).
More bitter cold is in store for much of the nation during the next couple of weeks.
Cloudy and cold with periods of snow, the snow will come down fast and furious for about a 6-hour period during the morning and early afternoon hours, the snow ends by mid-afternoon with accumulations of 2-4 inches, highs in the low 30’s
Becoming partly cloudy, very cold, lows near 20 degrees
Mostly sunny, very cold, near 30
Mostly clear, very cold, near 20
Mostly sunny and very cold, upper 20’s
Mostly sunny, cold, mid 30's
Mostly cloudy, cold, chance for rain or snow late, near 40
Partly sunny, windy, cold, snow showers possible, upper 30’s
If you are at work, stay at work; if you are at home stay at home as a wall of snow has moved into the region and it will snow hard through the morning and into the early afternoon hours. This “fast-moving” and "quick-thumping" system will end by early-to-mid-afternoon after dumping 2-4 inches of snow on the area. Once this storm passes by the weather will be dry and very cold in the Wednesday through Friday time frame. A significant storm will then pull out of the Deep South and head towards the Mid-Atlantic coast this weekend, but it is too early to tell if there will be enough cold air around for snow from that next system so rain is a possibility or some kind of mix.
Here we go again for the Mid-Atlantic I-95 corridor region with more accumulating snow on the way. A temperature gradient boundary zone that has been hanging around the eastern states for several days will again act as a conduit for moisture later tonight and Tuesday. This next batch of moisture will move in a southwest-to-northeast fashion reaching the Mid-Atlantic region early tomorrow. Tomorrow’s event should be primarily, if not completely, in the form of snow in Philly and NYC, but there is a chance that the precipitation begins as sleet in the DC metro region before quickly changing to all snow. Precipitation should break out near or just before daybreak in the DC metro region and then in the early-to-mid morning hours across Philly and NYC. This will be a “fast-moving, quick thumping” type of snowfall with a burst of heavy snow in DC during the morning hours, and in the late morning/mid-day hours in Philly and NYC. The snow should then end quickly from northwest-to-southeast by early tomorrow night.
The upper level pattern for this upcoming event is rather impressive with a strong jet streak playing a key role. It appears that the I-95 corridor region will be in the right/rear quadrant region of a strong upper level jet streak which is conducive to upward motion. Snow accumulations should be on average in the 3-6 inch range from DC-to-Philly, and 2-4 inches in the New York City metro region. We’ll have to see if any small-scale heavier snow bands set up on Tuesday which is quite possible given the expected strong dynamics associated with this powerful upper level jet streak. [12Z NAM 300 millibar winds forecast map for early Tuesday depicting the strong upper level jet streak at 150+ knots across the Northeast US (purple region)].
A few notes about yesterday's snowfall in Philly...Philly Int’l Airport officially recorded 8.6 inches which was only the 8th time in which 8 inches or more has fallen in the month of December and 3 of those 8 events have occurred in just the last 5 years. Also, yesterday's 8.6 inches of snow at PHL was more than recorded for the entire 2012-2013 winter season.
Finally, another storm threatens the Mid-Atlantic region this weekend with more significant snow and/or rain possible.
Cloudy and cold with occasional light rain or drizzle, highs in the low-to-mid 40’s
Cloudy and cold, snow possible towards morning, lows in the low 30’s
Mostly cloudy, cold, periods of snow with several inches of accumulation possible by nightfall, mid 30’s
Becoming mostly clear, very cold, low 20’s
Mostly sunny and very cold, low 30’s
Mostly sunny and still very cold, upper 20’s
Partly sunny, very cold, low 30’s
Mostly cloudy, cold, maybe snow showers, low-to-mid 30’s
Slightly milder air moved in overnight changing our wintry precipitation to plain rain and we'll continue to have some light rain or drizzle for part of the day. More moisture to our southwest will ride up an old frontal boundary zone on Tuesday in a southwest-to-northeast fashion and it looks like it'll be cold enough for all snow for this event across the NYC metro region. Snow is likely to begin during the early-to-mid morning hours on Tuesday and continue for much of the day with preliminary accumulation estimates on the order of 3-5 inches. Once this next system passes by, the second half of the week will be dry and very cold for this time of year.