Published: November 27,2015
(MORE: Latest Impacts of Cara | The Science of Naming Winter Storms)
A textbook combination of Arctic air plunging south and tropical moisture surging north will set the stage for freezing rain across a swath of the southern and central Plains through at least the first half of the weekend. In some areas, accumulating ice will create dangerous driving and walking conditions and may even be enough to down trees and trigger power outages.
Winter Weather Alerts
(INTERACTIVE: Winter Alerts | Radar)
Arctic cold air is plunging south through the Plains while an accompanying upper-level storm system continues to spin in place over the Great Basin.
This system is directing its energy and moisture into the Plains, as well as the Mississippi Valley, and will continue to do so through much of the holiday weekend, bringing a mess of sleet and freezing rain, along with some leftover snow, not to mention heavy rain.
(MORE: Thanksgiving Travel Forecast)
As if this weren't enough, this is the coldest air mass of the season so far in the West and the Plains.
Plains Ice Storm
Latest Radar
Saturday's Forecast
Power Outage Potential
Arctic cold air has plunged south into the Plains behind a sharp cold front. The shallow layer of below-freezing arctic air near ground level will slide underneath a large plume of warm, moist air from the Gulf of Mexico, setting the stage for a wintry mess of freezing rain and sleet that will continue through at least part of the holiday weekend.
Freezing rain first developed in the early morning hours of Thanksgiving in parts of northeast Colorado, eastern Wyoming, Nebraska and southern Minnesota and has spread southward along with the advance of cold air.
Now, freezing rain has zeroed in on a part of the southern Plains from eastern New Mexico to West Texas, central to western Oklahoma and southern Kansas.
As a result, the National Weather Service continues an ice storm warning for the eastern New Mexico to north-central Oklahoma portion of the above-mentioned area, including the city of Lubbock, Texas. These warnings are valid into Saturday. Ice storm warnings have since been expanded east to include the Oklahoma City metro area.
(MORE: Ice Accumulations and Impacts)
Freezing rain advisories were posted further northeast across portions of the Middle Missouri Valley, including the Kansas City metropolitan area, where lighter accumulations of ice are expected.
Where the deeper cold air manages to dislodge the warm layer just above ground level, any precipitation will change to light snow, from the northern Texas panhandle northward. Overall, freezing and frozen precipitation is expected through Saturday, from the southern High Plains to the Missouri Valley.
(MAPS: Weekly Planner)
Despite recent warmth, and warmer early-season ground temperatures, the arriving arctic air mass will lead to significant impacts from ice accumulation:
- Most roads will become icy and hazardous. The first to ice up will be untreated roads, bridges and overpasses.
- Furthermore, precipitation may begin as rain in some of these areas, followed by the arctic front, which could cause flash freezing on roads, even before freezing precipitation begins.
- In a few areas, some limbs or trees may break, and power outages will result.
- Strong north winds from 15-30 mph will lead to additional stress on power lines and any trees planted in cities, towns or on farms.
Snowfall Forecast
However, with potential ice accumulation forecasts trending slightly further east into more populated portions of the Plains, the level of ice accumulation and wind may produce spotty power outages that could last more than a day.
We do expect precipitation types to change from freezing rain to sleet, perhaps to snow, rather than many hours of freezing rain over a large area, which will mitigate, to some extent, this event from becoming a paralyzing, crippling ice storm.
(FORECAST: Amarillo | Oklahoma City | Wichita
If that weren't enough, ahead of the cold front, rain and thunderstorms are expected and locally heavy rainfall will bring the threat of flash flooding from Texas to the Midwest.
Patchy areas of snow may persist over parts of the Rockies, High Plains and Plains to the north of the ice-threat area, with light accumulations, that may further slicken roads through Saturday.
The aforementioned stuck upper-level low over the Great Basin will finally get moving over the Rockies and into the Plains from late Sunday into Tuesday. This could bring another winter storm to parts of the central and northern Plains and western Great Lakes Sunday night through Tuesday.
(MORE: Next Winter Storm?)
Arctic Blast
Morning Forecast Lows
Forecast Highs
The upper-level trough, or southward dip in the jet stream, will dive across the West and combined with a strong area of high pressure from Canada, the result will be the first blast of arctic air arriving in the West and Plains.
Overnight lows will dip below zero in some spots in the northern and central Rockies through Saturday morning.
This will lead to the coldest temperatures so far this season for many areas. A couple of examples include Helena, Montana, where the lowest temperature recorded so far this season had been 14 degrees on Nov. 21; Helena fell to 3 degrees below zero Thursday morning. Reno, Nevada has seen the mercury drop as low as 21 degrees on Nov. 11; lows in the teens are in the forecast Friday and Saturday nights.
The temperature at Big Piney, Wyoming crashed to 22 degrees below zero Friday morning, thanks to clear skies and fresh snow.
Oakland, California tied a record low Thursday morning when they fell to 35 degrees. Record lows were also tied or set Thanksgiving Day in Montague, California (13 degrees), and Quillayute, Washington (23 degrees). King City, about 90 miles southeast of San Jose, also tied a record low Friday morning (25 degrees).
(FORECAST: Great Falls, Montana | Casper, Wyoming | Denver)
High temperatures will remain very cold as well. Highs will be 10 to 30 degrees colder than what is normally expected for the end of November over parts of the Rockies and High Plains again on Saturday, while highs 10 to 20 degrees below average will persist over Nevada and parts of neighboring states.
Highs will only reach the teens and 20s in parts of the Rockies and adjacent High Plains, with 30s and 40s for the Pacific Northwest, Great Basin and portions of the central and southern Plains.
(FORECAST: Rapid City, South Dakota | Oklahoma City)
Ice Reports
As cooler air nudged south and east Friday, freezing rain was accumulating on many surfaces in Wichita, Kansas and Enid, Oklahoma. Up to one-quarter inch of ice accumulation was noted in several locations, including in Woodward and Berlin in Oklahoma. By Friday night, icing was beginning to take place across the Oklahoma City metro area, particularly on elevated surfaces as the temperature hovered around freezing.
Ice accumulating near Seiling
Other significant ice accumulation reports Friday included 3/8 inch on sidewalks in Blaine, Kansas, and 0.3 inch in both Beattie, Kansas and Wellington, Texas. Up to 1/4 inch of ice accumulation was reported at Omaha, Nebraska.
Snow Reports
Snow started to pile up on Tuesday across portions of the interior Northwest, Sierra Nevada and far northern Rockies. Some freezing rain was also reported in the Columbia Basin. Snow was reported in parts of Montana, Wyoming and Idaho on Wednesday.Bend, Oregon, reported 10 to 16 inches of new snow Tuesday night, with snowfall rates of 4 inches in 3 hours. This is quite impressive for this relatively dry plateau to the east of the Oregon Cascades, which only averages about 24 inches of snow each season. This heavy snow brought traffic to a standstill on U.S. 97 Tuesday night.
Farther south, up to 23 inches of snow fell around Crater Lake, which The Weather Channel recently named the snowiest place in Oregon.
Up to a foot of snow in the Sierra Nevada snarled traffic on Interstate 80 over Donner Summit in California Tuesday, as well. Up to 22 inches of snow was reported at Kirkwood Mountain Resort south of Lake Tahoe on the California side of the state line. On the Nevada side, Mount Rose Ski Area tallied 10 inches of snow, the top reported total in Nevada as of Wednesday afternoon.
Here are the top snowfall totals of at least 6 inches by state, so far:
- Nevada: 25 inches estimated on Tent Mountain, about 30 miles east of Elko
- Oregon: 23 inches near Crater Lake
- California: 22 inches at Kirkwood Mountain Resort
- Idaho: 14 inches in Buhl, about 100 miles southeast of Boise
- Wyoming: 14 inches at Sinks Canyon, near Lander in central Wyoming
- Colorado: 13 inches near Rye, about 25 miles southwest of Pueblo
- Montana: 8.5 inches near Clancy, which is just south of Helena
By Friday night, what little remained of Cara's snowfall was mainly confined to the Colorado Rockies and High Plains of western Kansas, as most of the precipitation over the Plains was either sleet or freezing rain.
(MORE: State-by-State Impacts)
Check back for updates and the latest information on Winter Storm Cara. The name Cara (CAH-ruh) is taken from the Latin word meaning "beloved."
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