2:00 PM | **Significant ice and snow for the DC metro region late Sunday night and Monday**

[Latest satellite image of the powerhouse Pacific Ocean storm; courtesy NASA]

Discussion

Overview The ingredients are coming together for another significant winter storm in the DC metro region that will likely include both an ice buildup and accumulating snow in the period from late Sunday night into Monday night. The first player in this upcoming event is a powerhouse storm system that will slam into California later today with substantial rainfall, thunderstorms, and strong wind gusts. This system will then cross the country over the weekend and its significant supply of moisture will arrive in the Mid-Atlantic region by Sunday night. A second crucial ingredient to the upcoming snowstorm is an extensive area of Arctic high pressure that will set up across the southern tier of Canada by the end of the weekend. One humongous high pressure system will be anchored over south-central Canada by Monday and there will be an extension of this into the southeastern part of Canada.

Preliminary storm details Light rain is likely to break out later on Sunday in the DC metro region and with temperatures up in the 40’s, there will be no problems on the roadways. Arctic cold air – anchored by strong Canadian high pressure – will slowly filter into the Mid-Atlantic region late Sunday night and early Monday and, as the colder air oozes in from the north, the rain will change to a wintry mix for awhile causing an icy build-up in the region. As the increasingly colder air continues to advance to the south and east, a changeover from a wintry mix to all snow will take place and accumulations of 3-7 inches are possible by the time the storm winds down later Monday evening with the higher amounts in the N and W suburbs of the District and the lower amounts on the southeast side. Temperatures will drop through the 20’s on Monday afternoon and will bottom out at very cold levels by early Tuesday morning – perhaps even down into the single digits in some spots. Bitter cold conditions will stick around for the rest of the day on Tuesday as clean-up efforts continue.

Updates will be posted this weekend at “thesiweather.com”.

7:00 AM | ****Brutal cold for today; winter storm watch for Sunday night and Monday with ice and snow a strong possibility****

6-Day Forecast

Today

Partly sunny, breezy, very cold for this time of year, highs struggle to reach 25 degrees (more than 20 degrees below normal)

Tonight

Mostly cloudy and very cold, lows in the upper teens

Saturday

Mostly cloudy, not nearly as cold, slight chance for a rain or snow shower, mid 40’s

Saturday Night

Mostly cloudy, cold, lows in the lower 30’s

Sunday

Mostly cloudy, cold, chance for rain late in the day or early at night, mid 40’s

Monday

Cloudy, breezy, colder, rain changes to ice and then to snow, can be a buildup of ice before the changeover to snow, low-to-mid 30’s

Tuesday

Becoming partly sunny, windy and cold, upper 20’s; brutal cold at night

Wednesday

Partly sunny, still very cold, near 30

Discussion

A powerful storm will slam into California later today and bring substantial rains to much of the state over the next 24-36 hours or so with as much as half a foot of rainfall in some areas. This strong storm will then cross the nation over the weekend with copious amounts of moisture and it will reach the Mid-Atlantic region by later Sunday. At the same time, very cold Arctic air will slowly drop southward into the Mid-Atlantic region and the result could be a substantial snowstorm on Monday north of the PA/MD border and a significant ice buildup just to the south of there across places like Virginia, Maryland and the DC metro region. In these areas that do indeed receive an ice buildup, there will be a changeover to accumulating snow as the colder air filters southward during the day on Monday. More bitter cold air will follow the early week storm in the Mid-Atlantic region and throughout much of the eastern U.S.

Video

httpv://youtu.be/omM90cCzeQE

2:15 PM | **Sunday night/Monday winter storm could produce significant snow across much of Pennsylvania and icing south of the PA/MD border**

Discussion

Overview One storm is hitting California today and a second and stronger system - currently still out over the Pacific Ocean - will hit that state from tomorrow into Saturday. Today’s storm will weaken as it crosses the country this weekend, but the second system will cause big problems in the Mid-Atlantic region on Sunday night and Monday. There is likely to be a dangerous combination early next week of brutally cold Arctic air slowly dropping southward into the Mid-Atlantic region at the same time copious amounts of moisture associated with the second California storm arrives here from our southwest. The result could be a major snowstorm across much of Pennsylvania and southern New York and significant ice and some snow is possible just south of the Pennsylvania/Maryland border including in the DC metro region.

Very preliminary details Precipitation should arrive in the Mid-Atlantic region on Sunday night and it may be in the form of rain or sleet for awhile, but as colder air filters in from the north, the precipitation is likely to change to all snow across much of Pennsylvania and southern New York and eventually to all snow south of the PA/MD border, but perhaps not until after an extended period of icing. Precipitation continues through the day on Monday and likely winds down Monday night or very early Tuesday. Brutally cold air will follow by mid-week in much of the eastern half of the nation.

Model comparisons The GFS computer forecast model has been predicting a relatively “colder’ solution for this upcoming event in recent model runs with more in the way of frozen precipitation across much of the Mid-Atlantic I-95 corridor whereas the European computer forecast model has been going back and forth between a “cold” and “warm” solution. Today, the Euro model has blinked and has now joined the GFS with a “colder” solution indicating more in the way of frozen precipitation for the Mid-Atlantic I-95 corridor and less in the way of plain rain. Stay tuned, this event is still days away, and the storm is not yet over the "data-rich" land mass of the western U.S. which can have an impact on computer model forecast output.

Short-term forecast on the Siberian express A “Siberian” cold front is currently plowing across central Pennsylvania and is causing snow showers and heavier snow squalls in the central mountains (e.g. near State College). Some of these snow showers - and perhaps even a heavier snow squall - will make it into the eastern part of Pennsylvania, New Jersey, southeastern New York later today along with gusty winds of up to 40 mph. Single digit temperatures can be expected for overnight lows in many locations along the I-95 corridor and brutally cold weather conditions will continue on Friday.

7:00 AM | Another strong cold front moves in today with Siberian air behind it...bitter cold for tonight and Friday...ice is a threat for Monday

6-Day Forecast

Today

Mainly sunny, increasingly windy and cold, a snow shower is possible this afternoon, highs in the mid-to-upper 30’s

Tonight

Mostly clear, breezy and brutally cold, lows not far from 10 degrees

Friday

Partly sunny, still brutally cold with highs temperatures in the mid-to-upper 20’s – more than 20 degrees below normal for this time of year

Friday Night

Mostly cloudy, very cold, lows near 20

Saturday

Mostly cloudy, not as cold, chance for snow or rain showers, upper 30’s

Sunday

Mostly cloudy, cold, chance for some rain late in the day, heavier precipitation arrives overnight, low 40’s

Monday

Mostly cloudy, cold, a wintry mix is likely and precipitation could eventually change to all snow, mid-to-upper 30’s

Tuesday

Mostly cloudy, cold, low-to-mid 30’s

Discussion

A strong cold front will arrive later today with increasing winds and a possible snow shower; especially, across the northern suburbs. The air mass behind this front originated in Siberia last week, crossed the North Pole, and will drop temperatures overnight to near 10 degrees in many locations. Friday will continue with the brutally cold conditions as high temperatures struggle to pass the 25 degree mark - some 20 degrees below normal for this time of year - and wind chills will be even lower.

By the weekend, attention will turn to the west as the remnants of two California storms will head towards the east coast. The first system will weaken as it crosses the country and might only produce some scattered snow or rain showers in the eastern states on Saturday. The second and stronger system will arrive late Sunday into Monday at the same time Arctic cold is slowly filtering southward from our north. The result could be a situation around here that features rain at the onset of this upcoming storm later Sunday and then a changeover to ice early Monday that could ultimately end up as all snow by late Monday. More brutally cold air will follow this upcoming storm by the middle of next week.

Finally, more information as to how cold this winter has been for the Upper Midwest...Chicago, Illinois is likely to end up with its third coldest winter ever (December through February time period) and Duluth, Minnesota is having its coldest winter since the 70's...thats the 1870's!

Video

httpv://youtu.be/x9SPyPQM6IY

3:00 PM Winter storm potential for early next week

Discussion

One storm is hitting California today and a second and stronger storm - currently out over the central Pacific - will hit that “drought-stricken” region from Friday into Saturday. Both of these systems will cross the country, but it is the second storm that is likely to cause big problems in the Northeast U.S. in terms of snow and ice early next week. There is likely to be a dangerous combination early next week with brutally cold Arctic air just to our north anchored by extremely strong high pressure and copious amounts of moisture heading this way from our west associated with the second California system.

On Saturday, the remnants of the first California storm will move into the eastern U.S. with clouds and some possible light snow, but it appears that nothing too significant will come from this system around here. By Sunday, an Arctic frontal boundary zone will be setting up shop in an east-to-west fashion across Pennsylvania backed up by a very strong Arctic high pressure system extending from south-central Canada to the Northern Plains. At the same time, moisture will be riding along the Arctic frontal boundary zone and the end result could be significant snow and/or ice for parts of the Mid-Atlantic region; especially, to the northwest of the big cities. There are still lots of details to be ironed out, but there is likely to be a battle in the big cities between rain and something frozen – at least for awhile – but even in those areas “all-frozen” precipitation is possible as colder air slowly filters southward early next week. This could end up being a two-part affair with one storm affecting the Mid-Atlantic region on Sunday night and Monday and then a second system from Monday night into Tuesday. The trend in some of the computer forecast models has been for a colder and colder solution for the upcoming event (i.e., increasing chances for frozen precipitation); however, the European model is noticeably on the "warmer" side and, in this case, it is an outlier. No matter what the result is precipitation-wise, brutal cold air will follow by mid-week throughout the eastern half of the nation anchored by strong Arctic high pressure. Stay tuned.

Finally, for some good news…the Phillies are playing in their 1st spring training game of the season.

7:00 AM | More snow during the early and mid-morning hours that can include heavier bursts of snow; very cold air air follows

6-Day Forecast

Today

Cloudy with some snow continuing into late-morning hours, new accumulations of a coating to an inch or two, watch for slick spots on roadways and occasional heavier bursts of snow, gradual clearing this afternoon, breezy, remaining cold, highs in the low-to-mid 30’s

Tonight

Partly cloudy, very cold, lows in the middle teens

Thursday

Mostly sunny, becoming quite breezy, still cold, mid 30’s

Thursday Night

Mostly clear, brutal cold, lows not far from 10 degrees

Friday

Sunny, very cold, mid-to-upper 20’s (more than 20 degrees below normal for this time of year)

Saturday

Mostly cloudy, cold, chance for some snow shower activity, mid-to-upper 30’s

Sunday

Mostly cloudy, cold, chance for some snow, sleet and/or rain, mid-to-upper 30’s

Monday

Mostly cloudy, cold, chance for some snow, sleet and/or rain, mid-to-upper 30’s

Discussion

Our active weather pattern continues today with another fast-moving upper-level disturbance generating some accumulating snow in the region this morning on the order of a coating to an inch or two. Watch for slick spots on roadways as temperatures will be well below freezing during the snowfall. This latest system departs by late morning with clearing skies this afternoon and it'll become very cold tonight with lows in the middle teens in some spots. Winds will increase on Thursday as the next strong cold front approaches and bitter cold temperatures are likely Thursday night and Friday with lows near 10 degrees in many of the subrubs and highs on Friday more than 20 degrees below normal for this time of year.

Looking ahead, two storms will slam into California over the next few days and they will both subsequently cross the country in a west-to-east fashion. The first of these systems could throw some clouds our way early in the weekend with light snow possible and then the second system is likely to bring more significant precipitation into the Mid-Atlantic region later this weekend and early next week. It is too early to tell the exact details of this particular storm that'll come to the region in the Sunday night-Tuesday time frame as there can be snow, sleet and/or rain, but precipitation amounts look to be significant.

Video

httpv://youtu.be/SXq4PfRs7kY

7:00 AM | Snow this morning and mid-day and then a break in the action and then more snow late tonight/early Wednesday

6-Day Forecast

Today

Mostly cloudy skies with occasional snow during the morning and mid-day hours, a coating to an inch or two likely, cold, highs in the mid-to-upper 30’s

Tonight

Mostly cloudy, cold, chance for some more snow late, lows in the low-to-mid 20’s

Wednesday

Mostly cloudy with some snow in the morning hours and small accumulations possible on the order of a coating to an inch or so, becoming mostly sunny during the afternoon, cold, low 30’s

Wednesday Night

Mostly clear, bitter cold, upper teens for lows

Thursday

Sunny, windy, cold, mid 30’s; bitter cold at night

Friday

Partly sunny, very cold, near 30

Saturday

Mostly cloudy, cold, chance for snow showers, mid 30’s

Sunday

Mostly cloudy, very cold, chance for some snow, low 30's

Discussion

A fast-moving impulse of energy will generate snow in the area this morning and mid-day with a coating to an inch or two possible and then, as a reinforcing cold air mass approaches the region late tonight, a wave of low pressure will form just off the Mid-Atlantic coastline. Snow is likely to break out again late tonight and continue into Wednesday morning as this low pressure system organizes near the coast and additional small accumulations are possible on the order of a coating to an inch or so. Once this mid-week low pressure system departs, very cold air that had its origins in Siberia will move into the Mid-Atlantic region.

Looking ahead, two storms will slam into California later this week and they will subsequently cross the country in a west-to-east fashion. The first and weaker system could spread some light snow into the eastern states early this weekend and then the second and stronger system could play an important role here in the Mid-Atlantic region late in the weekend or early next week.

Video

httpv://youtu.be/UHcwMbbI11o

12:45 PM | Follow the California storms this week for potential snow in the East early next week

Discussion

An important change is taking place this week with respect to the southern branch of the jet stream that will allow for two separate Pacific Ocean storms to slam into drought-ridden California with some much needed rain and snow. Both of these California systems will then travel across the country and, while the first system may be inhibited in growth by an extensive Arctic air mass, the second system may end up playing an important role in the eastern U.S. in about a week or so.

The first storm to hit California this week from the Pacific Ocean is destined to arrive in the Wednesday/Thursday time frame. The second, and most likely stronger system, should move into California in the Friday/Saturday time frame. The combination of these two systems will probably dump several inches of rain on coastal and low-lying sections of California over the next 5 or 6 days along with several feet of snow on the Sierra Nevada Mountains. This rainfall will not end the drought, but it will help quite a bit and perhaps be a sign of better things to come.

The first (weaker) system will then cross the country and it could spread some snow into the eastern states early in the weekend. However, an extensive cold and dry Arctic air mass will be entrenched in the eastern states at this time and this will likely reduce the threat for anything too significant although there are still several days to go and this system needs to be monitored.

The second and stronger system that should hit California at the end of the week is likely to have a bigger impact in the eastern states early next week. This system will also traverse the country in a west-to-east fashion and it should generate precipitation in the eastern states in about a week’s time. Strong high pressure to our north appears to be part of this potential atmospheric scenario early next week and this would increase the odds that enough cold air sticks around for at least some snow in the eastern states and it also would help to set up a “cold air damming” environment that can lead to significant “overrunning” precipitation.

Bottom line… it appears that the second and stronger system to hit California later this week in an newly activated southern branch of the jet stream could produce important precipitation amounts in the eastern U.S. in about a week’s time. The 00Z Euro model forecast maps show the location of the second California storm in the west on Friday night (above) and then in the east on Monday night (below). Stay tuned.

7:00 AM | Big changes this week with the return of cold and snow and the chill will last well into March

6-Day Forecast

Today

Mostly sunny skies, quite breezy and noticeably colder, highs in the low 40’s

Tonight

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

Tuesday

Mostly cloudy, cold, occasional morning snow with small accumulations possible, mid-to-upper 30’s

Tuesday Night

Mostly cloudy, cold, chance for some more snow late, mid 20’s

Wednesday

Cloudy, cold, more snow during the morning hours, low 30’s

Thursday

Partly sunny, breezy, quite cold, mid 30’s

Friday

Partly sunny, quite cold, mid 30’s

Saturday

Mostly cloudy, cold, chance for snow showers, mid 30’s

Discussion

After a very mild weekend, noticeably colder air has moved into the Mid-Atlantic region during the overnight hours and a reinforcing cold air mass will push into the area for the second half of the week. One impulse of energy should generate some snow activity on Tuesday with small accumulations possible and then, as the next cold air mass approaches the region, a wave of low pressure is likely to form near the Mid-Atlantic coastline early Wednesday. Some snow is likely to break out late Tuesday night/early Wednesday as this low pressure system organizes near the coast and additional small accumulations are possible. Once this mid-week low pressure system departs, another cold air mass that had its origins in Siberia will move into the Mid-Atlantic region.

Looking elsewhere, a change in the overall pattern over the Pacific Ocean will bring two separate systems into California later this week (Wed/Thurs) and during the early part of the weekend (Fri/Sat). The result should be substantial rainfall to coastal California over the next 5 or 6 days along with several feet of snow to the interior mountain locations (Sierra Nevada). The second system is likely to be the stronger one at the end of the week, but both systems could ultimately affect the weather in the eastern U.S. Specifically, the first (weaker) system could produce some light snow in the eastern states early this weekend and then the second (stronger) system has a chance to cause big problems in the eastern states in about a week's time. Stay tuned on that one.

Video

httpv://youtu.be/1MMsyLOZu90

2:25 PM | **Brutal cold returns later next week and it should be preceded by more accumulating snow**

Discussion

Brutal cold air is headed back to the Mid-Atlantic region for the second half of next week and it should be preceded by more accumulating snow. In fact, there are as many as four separate threats for snow next week as we make the transition from our current mild weather pattern to some more painful cold.

The first threat for snow does not look too significant at the current time, but it still has to be closely monitored. This threat for snow is for Sunday night/early Monday and will occur when an initial blast of cold air pushes into the Mid-Atlantic region ending the mild weather pattern. The second threat for snow in The Mid-Atlantic region comes during the day on Tuesday as an upper-level disturbance drops southeastward from the Great Lakes towards the east coast.

A third threat comes early Wednesday for the Mid-Atlantic region. By mid-week, a brutally cold air mass will have already invaded the Upper Midwest and it will have its eye set on the Mid-Atlantic region. In fact, temperatures in the Upper Midwest could be an amazing 40-50 degrees below normal by Wednesday in an area that has suffered the most during this widespread cold winter. As this brutally cold air mass - which had its origins in Siberia - approaches the east coast, it is likely to help generate low pressure near the Mid-Atlantic coastline and the result could be accumulating snow early Wednesday in the I-95 corridor from DC-to-Philly-to-NYC. Once that low pressure system departs, bone-crushing cold will take over in the Mid-Atlantic region for Wednesday night, Thursday and Thursday night.

Finally, a fourth threat for snow comes around Saturday of next week as a strong wave of energy pulls out of the Deep South towards the southeast U.S. coastline. It is way too early to tell; however, if this system will then make a ride up the east coast or if it will be suppressed to the south as a result of the extensive Arctic air mass that will be entrenched in much of the eastern U.S. at that time.

One final note: only 37 days till Opening Day.