Major storm system central and eastern US, lingering snows West

…Snow is expected from the Middle Missouri Valley into the Great Lakes…

…Snow will change over to freezing rain then to rain from parts of the Ohio/Tennessee Valleys to the Mid-Atlantic/Southern New England…

…Heavy rain possible from parts of the Lower Mississippi Valley/Central Gulf Coast to the Tennessee Valley…

A complex storm forming over the Central Gulf Coast/Tennessee Valley will move northward to the Great Lakes/Ohio Valley then into Southeastern Canada/New England by Monday evening. The system will pull moisture off the Gulf of Mexico northward overrunning the associated front over the Southeast/Central Gulf Coast into the cold air from the Middle Mississippi Valley to the Mid-Atlantic. A band of snow will develop over parts of the Middle Mississippi/Ohio Valleys into the Mid-Atlantic that will move northward into the Lower Great Lakes to New England by Monday morning. The snow will be forced out by a band of freezing rain/sleet that will, likewise, move northward from the Tennessee Valley/Southern Mid-Atlantic into the Northern Appalachians/Southern New England also by Monday morning. Rain will develop over parts of the Western Gulf Coast to the Carolinas that will similarly move northward into the Northern Mid-Atlantic/New England by Monday evening, with snow over the interior of Northern New England/Northern Appalachians, too. Showers and thunderstorms will develop along and ahead of the front over the Central Gulf Coast moving into the Southeast/Southern Mid-Atlantic by Monday evening. Behind the boundary, rain will continue over parts of the Western Gulf Coast to the interior Southeast/Southern Mid-Atlantic by Monday evening. Meanwhile, upper-level energy over the Southern Rockies will move northeastward to the Great Lakes/Southeastern Canada by Monday. The energy will trigger light snow over parts of the Southern/Central Rockies that will end by Sunday evening. A new area of snow will develop over parts of the Middle Missouri Valley that will expand into the Great Lakes by Sunday evening into Monday morning. Lake effect snow will develop over the Upper Great Lakes on Monday evening. Some additional upper-level energy will move over the Southwest/Southern Rockies by Monday evening. A small area of snow will develop over parts of the Southwest/Southern Rockies early Monday morning, that will begin to wane by Monday evening. In addition, a developing front over West-Central Canada will move southeastward into the Northern Plains by Monday evening. The system will produce light snow over parts of Northern High Plains early Monday morning, moving into parts of the Northern Plains/Upper Mississippi Valley by Monday evening.

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From the National Weathe rService

Broncos Game Day Forecast

Weak upper level disturbance moving through this morning will produce isolated light snow showers in the Denver Metro area through roughly noon then chances for snow decrease but do not completely diminish.  A snow flurry or two cannot be ruled out this afternoon with completely dry conditions developing this evening.  Any snow that falls during the game will only accumulate to a trace.  Arctic air mass remains in place and will result in temperatures only warming into the mid teens this afternoon.  Towards sunset temperatures will drop into the single digits.  Skies will remain cloudy to mostly cloudy today with light winds less than 10mph through the start of the game and then less than 5mph after halftime.  Wind chill values may dip into the single digits below zero but winds should not be a factor.  GO BRONCOS!!!

Widespread snows West, areas of rain East

…Freezing rain and sleet possible from parts of the Lower Mississippi Valley to the Central Appalachians/Northern Mid-Atlantic…

…Snow from the Middle Missouri Valley to the Upper Great Lakes and over parts of the Mid-Atlantic…

…Heavy rain possible from the Lower Mississippi Valley to the Tennessee Valley…

…Temperatures will be 10 to 35 degrees below average from the High Plains to Great Lakes/Central Gulf…

A storm over the Great Basin will move eastward to the Middle Mississippi Valley and merge with the system over the Southeast by Sunday evening. The system will produce snow over the Great Basin/Central Rockies and the higher elevations of California that will move eastward into the Central Rockies/Middle Missouri Valley by Sunday morning. The snow will wane to a few small areas over parts of the Central Rockies by Sunday evening. Rain will also develop over parts of Central/Southern California through Saturday evening. In the meantime, a front over the Southeast will begin to lift northward over the Central/Eastern Gulf Coast by Sunday evening and merge with the storm from the West. The system will produce showers and thunderstorms over parts of the Southeast/Southern Mid-Atlantic on Saturday. Rain will develop over parts of the Central Gulf Coast on Saturday and will lift northward into the Tennessee Valley/Southern Mid-Atlantic by Sunday. Snow will develop over parts of the Ohio Valley on Sunday morning that will expand into the Upper Great Lakes to the Northern Mid-Atlantic by Sunday evening. A band of freezing rain/sleet will develop over parts of the Tennessee Valley and the Mid-Atlantic on Sunday. Elsewhere, lake effect snow will develop over parts of the Upper Great Lakes through Sunday morning. In addition, high pressure will develop over the Pacific Northwest on Sunday. Another area of high pressure over the Northern Plains will move eastward to Northeast/Southeastern Canada by Sunday evening.

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Snow across N Calif, OR, Rain, Ice, Snow eastern US

..Snow expected from the Middle Mississippi Valley to parts of New England…

…A band of sleet/freezing rain is expected from parts of the Lower Mississippi Valley to parts of Northern Mid-Atlantic…

…Temperatures will be 10 to 30 degrees below average from the Plains to parts of the Mississippi Valley…

A front extending from the Northeast Coast to the Western Gulf Coast will move southeastward to the Southeast Coast by Saturday evening. Moisture from the Gulf of Mexico will pool along the boundary producing a bands of snow, sleet, and rain over parts of the Southern Plains to the Western portions of the Ohio Valley through Friday afternoon. Showers and thunderstorms will develop along the front from the Western Gulf Coast to parts of the Southern Mid-Atlantic through Saturday morning. In addition, rain will develop over parts of the Tennessee and Ohio Valleys into the Northern Mid-Atlantic/New England, moving mostly off the Northeast Coast by Saturday. Snow will develop over parts of the Ohio Valley into the Lower Great Lakes moving into parts of Northern New England by late Friday night, before ending on Saturday morning. As the front settles over the Southeast, rain will develop over the Western/Central Gulf Coast into the Southeast and Southern Mid-Atlantic by Saturday evening. A new band of sleet/freezing rain will develop over parts of eastern Texas also on Saturday evening. Behind the front, high pressure over the West-Central Canada will move southeastward to the Upper Mississippi Valley bringing cold air to the Upper Midwest to the Southern Plains. The cold air and upper-level energy will produce lake effect snow over the Upper Great Lakes through Saturday. Meanwhile, energy over the Pacific Northwest will dig southeastward over the Great Basin/Central Rockies by Saturday. The system will produce snow down to the coast over part of the Northwest and rain along parts of the Northern California Coast with snow developing over the higher elevations of Northern California on Friday. Rain will move southward over parts of Central/Southern California with snow over the higher elevations on Saturday. Additionally, snow will move into parts of the Great Basin/Southwest and the Northern/Central Rockies on Saturday, too. Snow will also develop over parts of the Central Plains.

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From the National Weather Service

Major ice storm Texas into Ohio Valley, Bitter cold Colorado

…Major ice storm expected from the Central Texas to the Ohio Valley…

…Heavy snowfall expected from Oklahoma to Lower Great Lakes… .

..Very cold airmass overspreading the West and Central U.S. with temperatures 10 to 30 degrees below normal…

A classic ice storm pattern is taking shape from the Southern Plains to the Ohio Valley. A strong cold front surging south and east will be overrun by mild return flow off the Gulf of Mexico, leading to a prolonged period of freezing rain and sleet from central Texas to the Ohio valley. Precipitation is expected to develop in response to a strengthening upper-level jet that remains well behind the surface cold front. As a result, the majority of the precipitation will fall into the cold sector of the storm, where significant icing is expected. The northern portion of the precipitation will fall in the form of snow, with a band of moderate snowfall expected from Oklahoma to Central Ohio. The cold front will slowly push eastward with precipitation spreading into the Northeast and Mid-Atlantic. In wake of the cold front pushing through the eastern U.S., a very cold airmass will overspread the central and western U.S. Temperatures will be 10 to 30 degrees below normal for the next few days. High temperatures will remain below zero for some parts of the northern Plains. A reinforcing shot of cold air will arrive in the Pacific Northwest toward the end of the period. Snowfall will be possible even within coastal Washington and Oregon.

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Heavy snows Great Lakes, Bitter Cold West with snow Colorado

…Heavy snow and icing will continue to affect the Upper Midwest and Upper Great Lakes on Wednesday…

…A major icing event is expected across the Arklatex and into southern sections of Missouri and Illinois beginning midday Thursday…

…An arctic intrusion will bring well below normal temperatures to much of the western/central states…

The active period of weather will persist through the short range forecast period extending until the end of the work week. The current National Weather Service hazards graphic is quite colorful with winter storm warnings and advisories extending from the Wasatch and Central/Southern Rockies up through the Northern Plains and Upper Midwest. Areas of Minnesota have already reported 1 to 2 feet of snow with more to come as a surface wave deepens while tracking from the Middle Mississippi Valley to the Upper Great Lakes on Wednesday. Strong vertical motions occurring to the north and west of this low track will bring another round of heavy snowfall to the northern tier of the country. The current WPC winter weather graphics indicate another 1 to 4 inches will be possible over northeastern Minnesota and extending into the Upper Peninsula of Michigan. Low-level temperature profiles will also remain favorable for a wintry mix along the rain/snow line interface. It appears the best chance for ice accumulations will occur from southeastern Minnesota up through sections of the Upper Great Lakes. Beginning midday Thursday, a potentially major icing event will be possible anywhere from the Southern Plains through the Ozarks and into the Lower Ohio Valley. The upper trof which has settled over much of the western and central U.S. has brought a significant shot of arctic air to these regions. The depth of this cold air will be rather shallow in nature with milder return flow from the Gulf of Mexico overriding this air mass. As precipitation will be ongoing when this occurs, many locations across the Arklatex will begin to see a wintry mix with freezing rain being of paramount concern. A quarter inch of ice accumulations are in the forecast from northeastern Texas through the Ozarks and into southeastern Missouri. Of course any sufficient icing may lead to a disruption in infrastructure including treacherous travel on roads and issues with aviation. Please visit the National Weather Service homepage at www.weather.gov for the most up to date information for more local concerns. The aforementioned arctic intrusion has brought temperatures to dangerously low values, particularly across the Northern Rockies and Northern Plains. During the next couple of days, forecast highs over these regions are in the negative single digits while lows plunge into the -20s Fahrenheit. Adding the element of wind will lower the apparent/wind chill temperatures to the -30s over areas of Montana and North Dakota. There will be quite the temperature contrast along the arctic front with upper 70s/lower 80s along the Gulf Coast while the northern tier is plagued by the frigid readings. Not even southern California will be spared from the surge of cold air. Hard freeze warnings are in effect for much of the Central Valley and cities such as San Diego will near record low temperatures. Elsewhere, a frontal system working its way through the Four Corners region will bring steady snowfall to the Central/Southern Rockies with accumulations being maximized across the San Juans. Looking out to the eastern states, the arctic boundary will eventually become a focal point for light to moderate rainfall over much of the Tennessee/Ohio valleys by Thursday afternoon/evening and continue into Friday. With colder air slowly filtering into the region a changeover to snow will occur on Friday across the lower Great Lakes.

 

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From the National Weather Service

Arctic air mass headed into Colorado

Arctic air will blast into Colorado by Tuesday, beginning a very long and protracted cold period for the region.  The initial cold front is expected to move through the Denver metro area by late Tuesday morning with snow and blowing snow developing by late Tuesday afternoon.   Snow and blowing snow will then continue through Wednesday, before diminishing Wednesday night.   This airmass will be the coldest of the season and persist through at least next weekend.   In fact, this could be the coldest airmass to overtake northeast Colorado since February 2011 when two separate bouts of frigid air brought below zero temperatures.

In the meantime, it would be prudent to prepare for the protracted cold spell and frigid temperatures now.  Prepare your home, auto, or business by checking your furnace and insulating or draining any exposed water pipes.  Make sure your car has a strong battery, proper antifreeze protection, and a good set of all season or snow tires.  Make sure your kids dress warmly before heading to school and give your pets or livestock adequate shelter from the cold.  This will be an unusually long period to be in the deep freeze. Get ready for it now while the temperatures are still mild.

From the National Weather Service

Rain NW Coast, heavy snows and bitter cold northern Rocky Mtns

…Winter storm to bring heavy snow to the higher terrain of the Central Rockies, as well as across the Northern High Plains and Upper Midwest…

…Well below normal temperatures move into the West and Central U.S….

A rather strong upper level low currently over the Pacific Northwest is forecast to continue dropping southeastward into the Northern Rockies by Wednesday, pushing a surface cold front south and east ahead of it. Very cold temperatures drawn in from Canada, combined with strong vertical lift, should be enough to support widespread heavy snow from the Northern and Central Rockies into the Northern Plains and Upper Midwest. Winter Storm watches, warnings, and advisories are currently in effect for much of the Intermountain West, Northern Plains, and Upper Midwest. Light to moderate snow will begin across the Northern Rockies, Northern Plains, and Upper Midwest on Monday night, and eventually spread into the higher terrain of the Central Rockies by Tuesday afternoon. At this point, it appears the heaviest of the snow accumulations should be confined to the highest terrain of the Central Rockies with storm totals ranging from 12 to 18 inches across the Wasatch range of Utah, to as much as 24 or more inches in the Central Rockies. Farther east across extreme Northern Minnesota and Wisconsin, anywhere from 10 to 18 inches of snow is possible. Behind the surface front, frigid temperatures are expected to move into much of the Western and Central U.S as a strong surface high pressure moves south from Northern Canada. By Wednesday, temperatures could be as much as 20 to 30 degrees below normal with daytime highs struggling to make it out of the single digits across the Upper Intermountain West, Northern Rockies, and parts of the Northern Plains. Gusty winds associated with a strong pressure gradient behind the front is also possible across these regions as the system continues to push eastward. Elsewhere, a coastal storm moving north in the Atlantic should be just far enough offshore to keep most of the precipitation out to sea. The exception to this is across Northern New England where some light to moderate precipitation could clip the coast lines, however the heaviest of the rain should remain over the open waters. Across the southeast, some scattered showers or thunderstorms may also be possible as clockwise flow around a surface high pressure brings southerly surface winds and limited moisture from the Gulf of Mexico into the region.

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Rain and snows across NW, and portions of the NE today

…Heavy snow and cold temperatures will impact the northwestern sector of the country…

…A potential coastal storm may bring moderate to heavy rainfall to the Outer Banks of North Carolina…

The initial low amplitude mid-latitude flow is forecast to quickly amplify as a strong trof surges southward into the Pacific Northwest. Before this system moves into the U.S…there will be quite the anomalous moisture content in place over Oregon/Washington with origins in the tropical Pacific. This abundant moisture working in accordance with strong onshore flow should produce quite the precipitation event over the topography of Washington and stretching into Oregon. During the next couple of days, over a half a foot of precipitation is expected across much of the Cascades, with snow dominating later on as colder air arrives from the north. Through Tuesday morning, the WPC winter weather forecast suggests over a foot of snow over the Cascades with somewhat higher amounts possible further inland across the Bitterroots, Sawtooth, Northern Rockies over Montana, and the Tetons. The intensity of the precipitation should gradually diminish by early Monday as the powerful upper low drops down from British Columbia. The arctic frontal boundary accompanying this system will erode much of the moisture in place although snow should persist given the lift from the upper low itself along with the usual upslope effects. This change in air mass will be rather pronounced with temperatures falling in excess of 15 degrees Fahrenheit from Sunday into Monday. However, the bigger changes lurk just beyond this period entering early/mid next week. As this dynamic system impacts much of the Western U.S., a warm front at the surface will gradually lift northward as moisture return from the Gulf of Mexico commences by Monday afternoon. As the aforementioned upper low begins to dominate the Pacific Northwest, multiple impulses will slide eastward off this low center which will help spawn areas of rain/snow showers across the Northern Plains/Upper Midwest. The fact the precipitation will be of the mixed bag variety should limit the snowfall accumulations with only a widespread 2 to 4 inches expected through early Tuesday. Elsewhere, a developing coastal low may bring some impacts to the eastern seaboard. However, the heaviest precipitation is forecast to stay just off the coast although some impacts cannot be ruled out across the Outer Banks.

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From the National Weather Service

Relatively quiet weather today across the US

…A fairly significant precipitation event is setting itself up for the Pacific Northwest…

…Light and scattered snow showers possible for the Great Lakes and into New England by Sunday…

Saturday should be another day of light and scattered snow or rain showers for the Washington Cascades and Northern Rockies. By Sunday however, a closed upper level vortex will begin dropping south from the Gulf of Alaska and precipitation will be on the increase across much of the Pacific Northwest and into the Northern Rockies. Strong onshore flow will stream plenty of moisture inland to fuel moderate to heavy rain for coastal areas of Washington and Oregon overnight Saturday and into Sunday, and heavy accumulating snow for parts of the Northern Rockies by Sunday afternoon. A few widely scattered snow showers also should not be ruled out for parts of the Northern Great Plains as the system moves farther inland, but little to no accumulation is expected there. Across the rest of the nation, the weather should remain fairly quiet. A clipper system moving into the Great Lakes region on Saturday could trigger a few scattered snow showers downwind of the lakes and across New England… with rain expected for the coastal regions. With the exception of extreme Northern New England, any accumulation of snow should remain north of the U.S./Canadian border. Down south, northeasterly flow off the Atlantic could bring a few scattered showers or thunderstorms for the coastal Southeast U.S.

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From the National Weather Service