7:00 AM | Big warmup coming with 60+ degrees on both weekend days

6-Day Forecast

Today

Mostly sunny, breezy, cold, highs near 40 degrees

Tonight

Partly cloudy, quite cold, lows upper 20's

Thursday

Mostly sunny, milder, near 50

Thursday Night

Mostly cloudy, chilly, mid-to-upper 30’s

Friday

Partly sunny, milder, mid-to-upper 50’s

Saturday

Mostly cloudy, very mild, chance for showers, low 60’s

Sunday

Mostly cloudy, very mild, rain likely, mid-to-upper 60’s

Monday

Cloudy, colder, more showers possible, low-to-mid 50's

Discussion

Our active weather pattern of recent days will finally settle down for the next few days and we’ll experience a significant warm up by the weekend. Unfortunately, the warmup is going to come with some rain attached to it, but temperatures should actually reach 60+ degrees by the time Sunday afternoon rolls around which will, of course, cause a massive meltdown of our current snowcover. A cold front will usher in colder air early next week after the wet and mild weekend and this will make for a quite cold Christmas Eve and a chilly Christmas Day.

2:15 PM | *Round two of our "doubleheader" winter event now getting underway*

Discussion

Round two of our latest winter storm event is now underway. One wave of low pressure passed through the Mid-Atlantic region this morning with a period of steady snow followed by scattered snow shower activity that was mixed with sleet and freezing rain at times. A second and more potent upper-level feature is following on its heels and will reach the east coast early tonight. This upper-level jet streak will cause an intensification of surface low pressure along the Mid-Atlantic coast and the precipitation shield will intensify and expand at the same time the low pressure system deepens. In fact, the area across southeastern Pennsylvania will experience steady snow over the next few hours and then the area from the southeastern side of the DC metro region eastward across the Delmarva Peninsula and northward through New Jersey will likely experience a period of steadier and heavier precipitation from late today through the evening. This is the type of setup that could throw a few surprises early tonight in terms of accumulating snowfall to the region from I-95 to the coastline. While there was a mixture of sleet and freezing rain at times earlier today, increasingly colder air aloft will increase the odds for all snow in much of this region - even down to the coastline of New Jersey by later tonight. Bottom line…all areas from near DC to the Delmarva to New Jersey and back inland to southeastern PA can expect more in the way of frozen precipitation over the next several hours with likely additional snow accumulations and slippery road conditions.

7:00 AM | Upper-level energy keeps us unsettled through tonight with the threat for rain and/or snow shower activity; big time warm up for the weekend

6-Day Forecast

Today

Mostly cloudy skies, chilly, a few rain or snow showers possible, highs near 40 degrees

Tonight

Rain or snow showers possible; otherwise, mostly cloudy, cold, lows in the upper 20’s

Wednesday

Mostly sunny, breezy, cold, upper 30’s

Wednesday Night

Partly cloudy, cold, upper 20’s

Thursday

Mostly sunny, milder, upper 40’s

Friday

Partly sunny, even milder, upper 50’s

Saturday

Mostly cloudy, very mild, chance for showers, near 60

Sunday

Cloudy, very mild, more rain possible, low 60's

Discussion

Our active weather pattern continues with a couple of clipper systems affecting the region through tonight with the threat for some rain or snow shower activity. Once these two features get out of here, the next couple of days look rather quiet and increasingly mild. Very mild weather is likely by the weekend with 60 degrees within reach for highs on both weekend days. The warm up will be associated with some rain as well, and then colder weather will return early next week.

Video

httpv://youtu.be/y3nOYOesNdo

1:45 PM | *Clipper doubleheader to bring more snow to the I-95 corridor*

[12Z NAM forecast map for early tomorrow evening showing precipitation associated with both clipper systems]

Discussion

It has been quite an active period in the Mid-Atlantic region over the past week or so with three different accumulating snow events to deal with and now two separate clipper systems will bring more snow to the region on Tuesday and Tuesday night.

The first clipper will push snow into the I-95 corridor region after about 4 am or so and it will likely have an impact on the Tuesday morning rush hour in Philly and New York City and perhaps even as far south as the DC metro region where they will be on the southern edge of the precipitation shield. The snow will continue in Philly through the morning and a brand new 1-3 inches can accumulate by mid-day with the tendency for the higher amounts to be north of Philly. Snow will last into the early-to-mid afternoon hours across the New York City region where 2-4 inches can accumulate as the clipper intensifies somewhat upon reaching the still relatively warm waters of the Atlantic Ocean. Then there will be a break for several hours across the I-95 corridor with just cloudy, cold and dry conditions before the second clipper races into the region from the northwest.

The second clipper is likely to move slightly farther south than the first system giving the DC region, Delmarva Peninsula, and the southern part of New Jersey a better shot at small accumulations later tomorrow night. While the Philly region may very well get more snow shower activity later tomorrow night from this second clipper, it is possible the bulk of its snowfall stays south of New York City. One final note - the typical 10-to-1 ratio of snow-to-precipitable water (e.g., 1 inch of rain equals 10 inches of snow) may be on the low side for these two events; especially, for the system coming tomorrow night. Upper air temperatures will be quite cold and dropping on Tuesday so the snow-to-rain ratio may be more on the order of 15-to-1 or so. The result of this: a light, fluffy type of snowfall that sweeps away rather easily.

7:00 AM | *A couple of shots at some snow (early Tuesday and Tuesday night); much milder weather returns later this week after a cold start*

6-Day Forecast

Today

Mostly cloudy, breezy, cold, highs in the mid 30’s

Tonight

Cloudy, cold, snow possible after 3 or 4am; especially, in the northern suburbs, lows in the mid 20’s

Tuesday

Snow showers possible early then remaining mostly cloudy, a bit milder, low 40’s

Tuesday Night

Snow showers or even a period of steadier snow possible; otherwise, mostly cloudy upper 20’s

Wednesday

Mostly sunny, cold, near 40

Thursday

Partly sunny, milder, upper 40’s

Friday

Mostly cloudy, even milder, showers possible, mid-to-upper 50’s

Saturday

Cloudy, mild with showers likely, mid-to-upper 50’s

Discussion

Cold air is firmly entrenched in the Mid-Atlantic region following the weekend storm and temperatures today will stay well below normal for this time of year. A couple of quick-moving clipper systems will track in our direction on Tuesday generating two possibilities for snow around here. The first possibility will occur late tonight and early Tuesday and then round two will come tomorrow night. While small accumulations are possible with either event, perhaps they will be more likely with the second system tomorrow night as that system moves farther south than the first and closer to our region. The next couple of days this week will be dry and moderately cold and then it’ll turn noticeably milder at the end of the week with showers likely.

Video

httpv://youtu.be/cyk8wAvyWzE

1:30 PM | **Saturday snowstorm focuses on the N and W suburbs of Philly and NYC**

Discussion

Here we go again! Another significant snow event is coming on Saturday to the Mid-Atlantic region from the PA/MD border across most of central and eastern Pennsylvania, northern New Jersey and southern New York State - and this includes the northern and western suburbs of Philly and New York City. Last weekend it was the Eagles football game that showcased to the nation a Philly snow event and tomorrow the Army/Navy game may do the honors. In fact, this will be the third accumulating snow event in just six days for the Philly metro region which is quite an accomplishment for any time of year, and especially for this early in the winter season. Low pressure will move from the Lower Mississippi Valley on Saturday northeastward to just off the Mid-Atlantic coast by early Sunday where it will strengthen. Snow will develop in the I-95 corridor on Saturday morning and continue through the day north of the PA/MD border before slightly milder air changes the snow to a wintry mix Saturday night that'll add a layer of ice on top; however, that changeover to a wintry mix won’t happen until significant snow accumulations occur in the N and W suburbs of Philly and NYC.

This will be a “conventional” snow event in the Philly and NYC metro regions in that there will be higher snowfall amounts as one goes farther and farther north and west of I-95 and lesser amounts closer and closer to the coastline. Accumulations on Saturday are likely to fall in the 3-6 inch range across most suburban locations N and W of Philly (e.g., Bucks, Montgomery and Chester Counties) with 1-3 inches in and around the immediate Philly metro region (e.g., Delaware and Philadelphia Counties), and an inch or less at the Jersey Shore. Elsewhere, 6-12 inches of snow can fall from northeastern PA (including the Pocono Mountains) to areas not far to the N and W of the NYC metro region, and 3-6 inches are likely in the immediate NYC metro region. Farther south, this does not look like a significant snow producer in the immediate DC metro region.

The Canadian forecast model has done a good job with the recent snow events and it certainly suggests significant snow will fall just to the N and W of Philly and NYC and also as far south as extreme northern Maryland near the Mason Dixon line. The forecast map is for early tomorrow evening and it depicts heavy snowfall just to the N and W of Philly and NYC. A wintry mix is likely for awhile later tomorrow evening in the N and W suburbs, but the damage will have been done with respect to snow accumulations.

7:00 AM | **Snow on Saturday morning is followed by a wintry mix and then plain rain**

6-Day Forecast

Today

Some sun early, clouds late, cold, highs in the upper 30’s

Tonight

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

Saturday

Cloudy, cold, snow in the morning that should then change first to a wintry mix and then to plain rain by later in the day, upper 30’s

Saturday Night

Cloudy, cold with rain or a wintry mix in the far northern and western suburbs, near 32

Sunday

Mostly cloudy, cold, upper 30’s

Monday

Partly sunny, breezy, very cold, low 30’s

Tuesday

Partly sunny, cold, low 40's

Wednesday

Partly sunny, cold, near 40

Discussion

This will be the third snow event in just six days for the DC metro region which is quite an accomplishment for any time of year, and especially for this early in the winter season. Low pressure will move from the lower Mississippi Valley on Saturday northeastward to off the Northeast coast by early Sunday where it will strengthen. Snow will develop in the DC metro region early Saturday and then change to a wintry mix followed by plain rain by later in the day as slightly milder air moves into the region. The precipitation will wind down late Saturday night and then more cold and dry weather will develop for the early part of next week.

This should be more of a “conventional” snow event around here with higher snowfall amounts as one goes farther and farther north and west of I-95. Accumulations on Saturday are likely to fall in the 1-3 inch range in and around the immediate DC metro region, an inch or less south and east of the District, but 3-6 inches are possible in the far northern and western suburbs across northern Maryland and western sections of Virginia.

Video

httpv://youtu.be/78Z416O3AqA

7:00 AM | Very cold air moves in today with teens likely overnight; snow on Saturday changes to a wintry mix or rain

6-Day Forecast

Today

Mostly cloudy early today and then mostly sunny, becoming breezy and remaining quite cold, highs only reaching near 30 degrees(normal high at DCA is 49 degrees)

Tonight

Mostly clear, bitter cold, lows in the mid-to-upper teens in many suburban locations

Friday

Increasing clouds, cold, mid-to-upper 30’s

Friday Night

Mostly cloudy, cold, mid-to-upper 20’s

Saturday

Cloudy, cold, snow likely at first then changing to a wintry mix or rain, upper 30’s

Sunday

Mostly cloudy, cold, upper 30’s

Monday

Partly sunny, windy, cold, low 30's

Tuesday

Partly sunny, windy, cold, near 40

Discussion

Cloudy skies this morning signal the arrival of another Arctic air mass that will send temperatures way down into the teens by late tonight. Clouds will thicken up later Friday and then moisture will slide into the region on Saturday from the Midwest and Deep South. It should be cold enough at the start of this next event for snow, but then enough milder air should move in to change the precipitation to a wintry mix or rain by Saturday night which would then wind down by early Sunday. If it does indeed snow on Saturday then that would be the third time in six days which does not happen often around here; especially, this early in the winter season. Preliminary snowfall estimates for this upcoming event: 1-2 inches in the suburbs with slightly lesser amounts in the District and points south and east of there. Another cold air mass will follow the weekend system for the early part of next week. Looking ahead, there are signs that the cold pattern will continue through December and some extremely cold air is possible during Christmas week in much of the country...not sure at this point if that will include the East or if it would be confined to the heartland and still on its way here.

Video

httpv://youtu.be/7rFJY3m4N54

2:00 PM | Coldest temperature ever recorded

Discussion

The hottest temperature ever recorded on Earth was 134°F just over a century ago in Death Valley, CA and now newly analyzed NASA satellite data from East Antarctica shows Earth set a new record for coldest temperature ever at -135.8°F. This new record is 50 degrees colder than anything that has ever been seen in Alaska or Siberia. It happened in August 2010 and was nearly matched on July 31st of this year when the temperature dropped to -135.3°F. The previous cold temperature record of -128.6°F, which was measured using a thermometer, had been set in July 1983 at a Russian research station in East Antarctica.

This news concerning the coldest temperature ever recorded has hit the news in recent days since it was presented earlier this week at a scientific conference in California. “It’s more like you’d see on Mars on a nice summer day in the poles” said the scientist presenting the results. He added “I’m confident that these pockets are the coldest places on Earth”.

The discovery was made by analyzing global surface temperature maps using data from remote sensing satellites. Specifically, the Antarctica measurements were made by the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor on board NASA's Aqua satellite and by Landsat 8, a satellite launched early this year by NASA and the U.S. Geological Survey. In many respects, satellite observations for temperatures are now preferred over conventional measurements made by thermometers which often have, for example, “urban heat island” effects to deal with when comparisons are made to other time periods in the past. After studying 32 years’ worth of satellite data they found that temperatures had plunged to record lows many times on a high ridge between Dome Argus and Dome Fuji on the East Antarctica Plateau. The report also maintains that the winters of 1997, 2001, 2003 and 2004 showed several temperature minima below -90°C.

Despite the new recorded low temperature, it will not be entered into the Guinness Book of World Records because the temperature was satellite measured. The official record low temperature will continue to be the -128.6°F measured (by thermometer) in July 1983 and, of course, the Death Valley high temperature record was based on a thermometer reading a century ago.

7:00 AM | Dry and very cold weather through Friday; weekend storm threat with snow, ice and rain possible

6-Day Forecast

Today

Mostly sunny and very cold, highs near freezing (normal high at DCA is 49 degrees)

Tonight

Becoming partly cloudy, bitter cold, lows in the upper teens

Thursday

Mostly sunny, very cold, mid 20’s

Thursday Night

Mostly clear, bitter cold, middle teens

Friday

Mostly sunny, still very cold, mid-to-upper 30’s

Saturday

Cloudy, cold, snow likely that could then mix with or change to sleet and/or rain, near 40

Sunday

Chance for rain, sleet and/or snow early, cold, near 40

Monday

Partly sunny, windy, very cold, low-to-mid 30’s

Discussion

Dry and very cold weather will dominate through Friday and then attention will turn to a developing low pressure system across the south-central US. That low looks like it will intensify as it consolidates near the Northeast US coastline during the upcoming weekend. It is still too early to call the precipitation-type for this next storm and a wintry mix of rain, sleet and/or snow is a possibility for the metro region.

Video

httpv://youtu.be/HkUM-zNYqyE