1:00 PM | ***Friday to Wednesday - the worst weather that winter has to offer***

[12Z GFS forecast map for next Tuesday early afternoon (blue=snow); map courtesy "tropicaltidbits.com", NOAA]

Discussion

Overview Get ready; it’s going to be a wild ride. The stretch from Friday to Wednesday will feature some of the worst weather that winter can offer in this part of the country. All of the following are on the table for the 6-day period from tomorrow through next Wednesday:

- Painful cold with 0 degrees within reach (Sunday AM, Monday AM) - Weekend accumulating snow (late Saturday, Saturday night) - Very strong winds with potentially damaging wind gusts (Sunday) - Dangerous sub-zero wind chills (Friday and especially on Sunday) - Significant snow threat (late Tuesday into early Wednesday)

Here are the details: Arctic air arrives today in the Mid-Atlantic region accompanied by snow showers and increasing winds. Those winds will remain strong tonight and temperatures will plunge in the overnight hours into the single digits in many suburban locations by early Friday. The winds remain strong through much of the day on Friday and this will produce sub-zero wind chills at times before the wind finally relaxes noticeably early tomorrow night.

On Saturday, another clipper system and Arctic front will be plowing towards the I-95 corridor from the Great Lakes region. This system has more potential in terms of snowfall in our area compared with today’s frontal system. In fact, snowfall on the order of a coating to two inches is possible late Saturday and Saturday night in the DC metro region, 1-3 inches in Philly, and 2-5 inches in NYC associated with this next Arctic blast. Then, Sunday promises to be the coldest day yet with painful cold, dangerous sub-zero wind chills, and potentially damaging wind gusts past 50 mph. The last thing we need on Sunday is for scattered power outages to develop, but that possibility cannot be ruled out with the most powerful winds likely late Saturday night and early Sunday.

After a bitter cold start on Monday - near 0 degrees in many portions of the I-95 corridor - moisture will begin streaming towards us from the south-central US. The combination of very cold ground temperatures, an entrenched Arctic air mass in the Northeast US and copious amounts of “southern” moisture does not bode well for the Mid-Atlantic region. Indeed, this could turn into a significant snow event for the Mid-Atlantic region from late Tuesday into early Wednesday, but since the storm track cannot be pinned down quite yet, it is just too early to make this call. And yes, this mid-week storm will be followed by more brutal cold.

Buckle up…the next 6 days will be quite interesting.

[12Z GFS forecast map for late Tuesday night (blue=snow); map courtesy "tropicaltidbits.com", NOAA]

Video

httpv://youtu.be/7vLfp462510

7:00 AM | ***An Arctic blast arrives later today only to be followed by another Arctic front late Saturday...the second blast will likely be accompanied by accumulating snow and the coldest air mass yet this season***

6-Day NYC Forecast

Today

Mostly cloudy, becoming windy, cold, occasional snow showers during the mid-day and afternoon hours, perhaps a heavier burst of snow producing a quick coating to an inch or two, highs in the middle 30’s

Tonight

Snow showers ending early, windy and becoming brutally cold, lows in the mid-to-upper single digits in many suburban locations with sub-zero wind chills

Friday

Mostly sunny, windy, bitter cold, mid-to-upper teens for highs with sub-zero wind chills

Friday Night

Partly cloudy, winds die down, brutal cold, low teens

Saturday

Increasing clouds, becoming windy, cold, snow late in the day and at night with accumulations likely, mid 20’s

Sunday

The coldest day of the winter so far…partly sunny, very windy with potential damaging wind gusts, painfully cold, low-to-mid teens for highs and dangerous sub-zero wind chills

Monday

Mostly sunny, breezy, very cold, near 20 degrees for highs after a bitter cold start

Tuesday

Mostly cloudy, quite cold, snow likely late, low 30’s

Discussion

A vigorous Arctic cold front is headed our way and it’ll generate scattered snow showers here during the mid-day and afternoon hours – perhaps even a brief heavier burst of snow in a snow squall. Accumulations from this frontal system should be on the order of a coating to an inch by early tonight and there can be slick spots for the evening commute. Temperatures will plunge in the overnight hours bottoming out in the upper single digits in many suburban locations by early tomorrow morning. Winds will pick up in intensity later today and remain strong through much of Friday generating sub-zero wind chills at times.

Before this Arctic air mass even has a chance to modify, another one will be fast-approaching as we begin the weekend and this one will be downright painful. By late Saturday, a clipper system and its associated Arctic front will be dropping southeastward across the Great Lakes and this will generate some snow in the area from late Saturday into early Sunday and perhaps even a period of steadier accumulating snow (2-5 inches of accumulation on the table for this event). The clipper system will intensify rapidly off the Northeast US coastline once it passes over the relatively warm waters of the western Atlantic Ocean late Saturday and brutally cold air will flood into the Mid-Atlantic region by Sunday. In fact, Sunday should turn out to be the coldest day of the winter so far in the eastern US all the way from Maine to Florida and low temperatures on Sunday and Monday could flirt with the 0 degree mark in many I-95 corridor locations. Winds will be very strong on Sunday and could be potentially damaging - power outages are the last thing we need on Sunday, but that possibility cannot be ruled out. Another accumulating snow threat will come Tuesday into Wednesday as tons of “southern” moisture heads right towards the Mid-Atlantic region. This storm could also produce significant ice and perhaps even plain rain in the area...just too early to make that call yet.

Video

httpv://youtu.be/7vLfp462510

1:30 PM | **Back-to-back Arctic invasions to produce amazing cold around here by early Sunday**

Discussion

Overview The normal high temperature for today at Philly’s International Airport is 43 degrees and we are going to end the day several degrees below that mark, but this cold is nothing compared to the type of cold that is coming. Back-to-back Arctic invasions will send temperatures plummeting in the Mid-Atlantic region over the next few days and the second blast is likely to feature the coldest air of the season so far in much of the area from Maine to Florida. The last time temperatures dropped to less than 10 degrees in Philly during the month of February was in 1996 (6 degrees on 2/6/96). There is little doubt that Philly will see temperatures that low on Sunday morning (and again on Monday morning). The last time sub-zero readings occurred in Philly during the month of February was in 1979 (-2 degrees on 2/11/79) and this is not out of the question for the Sunday/Monday Arctic blast.

Thursday night/Friday Arctic blast A clipper system and its associated Arctic frontal system will arrive in the Mid-Atlantic region later tomorrow with scattered snow showers - perhaps even a heavier burst of snow - along with strengthening winds and then it’ll turn brutally cold behind it late tomorrow night and Friday. Temperatures early Friday could bottom out in the upper single digits in some suburban locations along I-95 and they will struggle to reach the 20’s on Friday along with much lower wind chill values.

Sunday/Monday Arctic blast Before that late work week Arctic air mass even has a chance to modify, another clipper system and its associated Arctic front will be plowing towards the Mid-Atlantic region. This system will be accompanied by snow for the I-95 corridor along with strengthening winds from later Saturday into early Sunday and it will usher in absolute frigid air for Sunday and Monday. The snow could turn out to be rather significant in portions of the Northeast US; especially, from New York City north and east. Sunday is liable to turn out to be the coldest day of the winter so far in much of the region between Maine and Florida. Low temperatures early Sunday morning and again early Monday morning could plunge to 0 degrees in many parts of the Mid-Atlantic region. High temperatures on Sunday will be confined to the teens in the I-95 corridor and with winds gusting up to 40 mph or so, there will be dangerously low (sub-zero) wind chill values.

The 12Z GFS 96-hour forecast map for low temperatures on Sunday morning (above) show below zero readings just to the west of the NYC metro region, near zero in the Philly suburbs, and low-to-mid single digits near DC (map courtesy Weather Bell Analytics). The 12Z GFS 96-hour 2-meter temperature anomaly forecast map for Sunday (below) shows the entire eastern half of the nation in a deep freeze and some sections (in purple) are more than thirty degrees below normal for this time of year (map courtesy Weather Bell Analytics).

7:00 AM | **Two Arctic invasions over the next few days with the first producing snow showers here later tomorrow and then the second can generate significant accumulating snow from late Saturday into early Sunday**

6-Day Forecast

Today

Mostly sunny, cold, highs in the low 30's

Tonight

Mostly cloudy, cold, lows in the middle 20’s

Thursday

Cloudy, becoming windy, cold, occasional snow likely during the afternoon, low 30’s

Thursday Night

Snow showers ending early with total accumulations on the order of a coating to an inch or two, windy and turning brutally cold, lows in the upper single digits

Friday

Mostly sunny, windy, bitter cold, upper teens for highs with below zero wind chills

Saturday

Increasing clouds, becoming windy, cold, snow likely late in the day and at night, low 20’s

Sunday

Perhaps the coldest day of the winter so far…snow possible early then becoming partly sunny, windy, bitter cold with dangerous wind chills, highs only reaching the middle teens with dangerous wind chills

Monday

Mostly sunny, breezy, still very cold, near 20 degrees

Discussion

A vigorous Arctic cold front is headed our way and it is likely to generate snow showers during the mid-day and afternoon hours on Thursday along with increasing winds. There can even be a burst of heavier snow with a quick coating to an inch or two possible in the area by early tomorrow night. Temperatures by early Friday morning will likely bottom out in the upper single digits in many of the N and W suburbs of the NYC metro region. Before that late week Arctic air mass even has a chance to modify, another blast will be fast-approaching right on its heels. By late Saturday, a clipper system and its associated powerful Arctic front will be dropping southeastward across the Great Lakes and it is likely to generate increasing winds and snow showers around here from later Saturday into early Sunday and there can even be a period of steadier snow with several inches of accumulation possible. The Arctic invasion that arrives here by Sunday morning will likely be the coldest of the season so far for much of the eastern US from Maine to Florida. Sunday is likely to be the coldest day here so far this winter with dangerous wind chills. The bitter cold will continue into early next week and accumulating snow is quite possible here from Tuesday into Wednesday of next week.

Video

httpv://youtu.be/kEBA4RVvvdI

7:00 AM | **Next Arctic blast arrives late Thursday and then a second - perhaps the coldest yet - arrives on Saturday night...both Arctic blasts to be accompanied by some snow**

6-Day Forecast

Today

Mostly cloudy this morning, some clearing this afternoon, cold, highs in the low-to-middle 30’s

Tonight

Partly cloudy, cold, lows in the lower 20’s

Wednesday

Mostly sunny, cold, near 30 degrees

Wednesday Night

Mostly cloudy, cold, mid 20’s

Thursday

Mostly cloudy, becoming windy, cold, snow showers or even a period of steadier snow during the afternoon and evening, low 30’s; brutal cold at night

Friday

Mostly sunny, windy, bitter cold, upper teens

Saturday

Increasing clouds, becoming windy, cold, snow likely late in the day and at night, low 20’s

Sunday

Perhaps the coldest day of the winter so far...Mostly sunny, windy, brutal cold, dangerous wind chills, middle teens

Discussion

The low pressure system responsible for yesterday’s precipitation will move away today and high pressure will edge into the Mid-Atlantic region. As a result, it’ll be relatively tranquil around here for the next couple of days with moderately cold conditions. By late Thursday, however, a vigorous Arctic cold front will be headed our way and it is likely to generate strong winds and snow showers Thursday afternoon and evening – perhaps even a heavier snow burst. Temperatures by early Friday are likely to bottom out in the single digits in many I-95 corridor suburban locations.

Before that late week Arctic air mass even has a chance to modify, another one will be approaching on its heels and this one could be the worst of the season so far in the eastern US from Maine to Florida. By late Saturday, a clipper system and its associated Arctic front will be dropping southeastward across the Great Lakes and it is likely to generate strong winds here late Saturday into early Sunday along with snow showers or even a period of steady accumulating snow. Sunday could turn out to be the coldest day of the winter so far in the much of the eastern US with strong winds and seriously cold wind chill values.

12:00 PM | **Stormy and cold pattern developing for the next few weeks with multiple Arctic air outbreaks and numerous storm threats**

Discussion

Overview The pattern setting up for the next few weeks looks quite active and cold with multiple Arctic air outbreaks and storm threats. The southern branch of the jet stream will become more active and this will push Pacific Ocean moisture into the southern US which can move across the nation into the eastern US. After today’s precipitation event, there will be a couple of tranquil days in the Mid-Atlantic region with moderately cold conditions, but then the next clipper type of low pressure system and its associated Arctic blast will be ready to pounce on the area by Thursday night. Before that late week Arctic air mass even has a chance to modify, another clipper system and associated Arctic invasion will be plunging towards the Mid-Atlantic region by Saturday night. Beyond that, it appears yet another storm threat is likely around Tuesday or so of next week and this one will feature lots of moisture from the southern states. That storm next week could ultimately turn into a significant winter storm for the Mid-Atlantic region, but the storm track is, of course, still uncertain this far in advance.

This afternoon and tonight Colder air continues to trickle into the I-95 corridor as our Monday progresses and this will lead to mainly frozen precipitation in the Philly and NYC metro regions for the rest of this event. In Philly, the intermittent precipitation should fall as sleet and/or snow this afternoon with a change to all snow likely tonight. Accumulations by later tonight can be on the order of a coating to an inch with slick spots on untreated surfaces. In the NYC metro region, any wintry mix early this afternoon is likely to become all snow by later this afternoon and accumulations of snow and ice by later tonight should be on the order of 1-2 inches with slick spots on untreated surfaces. In DC, any plain rain that falls this afternoon is likely to turn into a wintry mix of freezing rain and sleet tonight, perhaps even ending briefly as all snow late tonight. Slick spots are likely on untreated surfaces in the overnight hours and there can be a coating of snow and/or ice.

Thursday night clipper and powerful Arctic blast By late Thursday, the next clipper and powerful Arctic front will blast into the Mid-Atlantic region with strengthening winds and numerous snow showers which could even include a heavier snow squall and/or a period of steadier snow. The upper-level pattern at 500 millibars for Thursday night is quite impressive with a deep trough of low pressure situated right on top of the Mid-Atlantic region (below). This will allow for rapid development of the clipper system once it reaches the warmer waters of the western Atlantic and this could lead to an all-out blizzard for – you guessed it – portions of New England. Temperatures by early Friday will bottom out in the single digits in many suburban locations along the I-95 corridor.

[500 millibar height anomaly forecast map for late Thursday night with deep upper-level trough over the Mid-Atlantic; map courtesy "tropicaltidbits.com"]

Saturday night clipper and powerful Arctic blast By late Saturday, another clipper system will be dropping southeastward from the Great Lakes region into the Mid-Atlantic and this system could generate numerous snow showers in the I-95 corridor late Saturday into early Sunday – perhaps even a period of steadier snow. Once again, a deep upper-level trough will develop in the Mid-Atlantic region (below) in very similar fashion to the Thursday night Arctic blast. As with the Thursday night event, this type of upper-level pattern may allow for rapid development of the clipper system once it reaches the warmer waters of the western Atlantic. This clipper will usher in another brutally cold Arctic air mass for the latter part of the weekend and the early part of next week. In fact, it may turn out that the temperatures early Sunday morning are at the lowest levels seen so far this winter in much of the Northeast US.

[500 millibar height anomaly forecast map for Sunday morning with deep upper-level trough over the Mid-Atlantic; map courtesy "tropicaltidbits.com"]

7:00 AM | Wintry mix changes to all snow and small accumulations are likely...another bitter Arctic air mass arrives late Thursday

6-Day Forecast

Today

A wintry mix of sleet and/or freezing rain becoming mainly snow by later today, cold, temperatures hold in the low-to-mid 20's

Tonight

Snow and/or sleet becoming all snow, total accumulations of snow and/or ice on the order of 1-2 inches by later tonight, cold, temperatures hold near 20 degrees

Tuesday

Partly sunny, cold, low 30’s

Tuesday Night

Mostly clear, quite cold, mid-to-upper teens

Wednesday

Partly sunny, cold, low 30’s

Thursday

Mostly cloudy, becoming windy, cold, snow showers likely late and perhaps a heavier snow squall, near 35 degrees

Friday

Mostly cloudy, windy, bitter cold, upper teens

Saturday

Increasing clouds, windy, quite cold, snow showers possible late or at night, low-to-mid 20’s

Discussion

Colder air will continue to filter into the NYC metro region today and this is likely to cause a changeover of the intermittent wintry mix of sleet and/or freezing rain to mainly just snow by later today or early tonight. Temperatures will hold at levels well below freezing and there can be accumulations of snow and/or ice by late tonight on the order of 1-2 inches. The low pressure system responsible for today’s precipitation will move away by early Tuesday and high pressure will edge in keeping us moderately cold for the next few days. A powerful Arctic front will arrive late Thursday with strong winds, snow showers and perhaps even a heavier snow squall and low temperatures by early Friday are likely to re-visit the single digits. A clipper system with a reinforcing Arctic shot is likely to arrive late Saturday into early Sunday with more brutal cold air and possible snow showers. Overall, the unfolding weather pattern looks quite stormy and cold for the next couple of weeks with multiple Arctic air outbreaks and multiple storm threats.

Video

httpv://youtu.be/N9MKo5iiF0Y

7:00 AM | Unsettled weather later this weekend into Monday...rain showers should evolve into a wintry mix and then all snow...bitter cold outlook for the end of next week and beyond

6-Day Forecast

Today

Partly sunny, blustery, very cold, highs in the low-to-mid 20’s with lower wind chills

Tonight

Mostly cloudy, cold, lows in the lower 20’s

Saturday

Mostly cloudy, milder, snow showers possible, mid 30’s

Saturday Night

Mostly cloudy, mild, chance for snow or rain showers, low 30's

Sunday

Mostly cloudy, mild, chance for rain showers, near 40 degrees

Monday

Mostly cloudy, colder, a wintry mix becomes all snow with minor-to-moderate accumulations possible, low 30's

Tuesday

Mostly cloudy, cold, low 30’s

Wednesday

Partly sunny, cold, near 30 degrees

Discussion

Single digit temperatures were quite prevalent early this morning in N and W suburban locations up and down the I-95 corridor (e.g., Dulles Airport, VA at 9 degrees, Pottstown, PA at 6 degrees). In fact, temperatures reached zero or below this morning in many locations across upstate Pennsylvania (e.g., State College at 0 degrees, -12 degrees at Bradford, PA). This entrenched Arctic cold will keep temperatures well below normal today to close out the work week, but there will be a noticeable modification in temperatures on Saturday. It'll remain relatively mild on Sunday as well, but then colder air will trickle in during the Sunday night and Monday time period. As a result, rain showers on Sunday in the I-95 corridor could evolve into a wintry mix by late Sunday night or Monday and there can even be a changeover to all snow as the new work week begins. Looking ahead, it looks like an incredibly cold air mass will arrive in the Northeast US late next week and the 7-days centered around the middle of the month could turn out to be one of the coldest weeks around here in a long, long time.

Video

httpv://youtu.be/rc0PL_QBwUg

7:00 AM | *Another Arctic blast rides in with snow showers and strengthening winds...single digits possible late tonight

6-Day Forecast

Today

Snow likely early with a quick coating to an inch or two and some slick spots, gradually becoming partly sunny and windy during the mid-day and afternoon hours, temperatures drop through the 20’s during the day, much lower wind chill values

Tonight

Windy and brutally cold with partial clearing, lows in the single digits, wind chills below zero

Friday

Mostly sunny, blustery, very cold, low 20’s

Friday Night

Mostly cloudy, quite cold, mid-to-upper teens

Saturday

Mostly cloudy, not as cold, upper 30’s

Sunday

Mostly cloudy, cold, chance for snow or a mixed bag of precipitation, low-to-mid 30’s

Monday

Mostly cloudy, cold, chance for snow, near 30 degrees

Tuesday

Mostly cloudy, cold, chance for snow, near 30 degrees

Discussion

Another Arctic blast has arrived with snow showers likely and a quick coating to an inch or two is possible. Winds will pick up as the day progresses and temperatures will slowly drop through the 20’s. By late tonight, single digits will be common in suburban locations and the wind chill values will be below zero. Friday remains quite cold, but there will be a noticeable moderation in temperatures on Saturday. That moderation will be short-lived; however, as another cold shot will arrive later in the weekend leading to an extended period of unsettled weather. Snow or a mixed bag of precipitation is likely on Sunday and then, as it turns colder early next week, snow might become more prevalent with low pressure organizing near the Mid-Atlantic coastline.

7:00 AM | Moderation in temperatures this afternoon, but Arctic cold returns early tomorrow; some snow accompanies the cold blast with a coating to an inch or two possible

6-Day Forecast

Today

Mostly cloudy, becoming milder this afternoon, highs will flirt with the 40 degree mark

Tonight

Mostly cloudy, turning colder, some snow likely late, lows in the upper 20’s by morning

Thursday

Some snow likely in the morning with new accumulations of a coating to an inch or two, becoming windy during the afternoon and partly sunny with temperatures slowly dropping after early day highs near 30 degrees

Thursday Night

Windy and brutally cold with partial clearing, lows in the single digits

Friday

Mostly sunny, very cold, low 20’s

Saturday

Mostly cloudy, milder, upper 30’s

Sunday

Mostly cloudy, cold, chance for snow or perhaps a mixed bag of precipitation, near 30 degrees

Monday

Mostly cloudy, cold, chance for snow, upper 20’s

Discussion

Temperatures will moderate today – perhaps reaching the 40 degree mark in parts of the metro region – but another Arctic invasion is ready to pounce on the northeastern US. A strong Arctic front will arrive early tomorrow and it will generate some snow late tonight and early Thursday that can produce a coating to an inch or two of new accumulations. More bone-chilling cold will follow with strong winds from later tomorrow into Friday before moderation takes place to begin the weekend. That moderation on Saturday will be short-lived; however, as another cold shot will arrive later in the weekend leading to an unsettled period of weather early next week. Snow or a mixed bag of precipitation is possible on Sunday and then, as it gradually turns colder, snow is more likely to be the precipitation-type on Monday as low pressure tries to form near the Mid-Atlantic coastline.

Video

httpv://youtu.be/AUZS20v35Vc