Wild Week of Winter Weather Across Most of U.S.Temperatures updated Dec. 8
A large winter storm, designated as ‘Cleon’ by The Weather Channel, affected most of the U.S. Tuesday through Friday (November 3-6) and was followed by extreme cold in the Rocky Mountain States and Upper Midwest. Record warmth preceded the storm in the Southeast while an unrelated storm brought low-level snow to Oregon and California on Friday. Here is a brief summary of the main events.
Although winter is still officially two weeks away it has already commenced climatologically, and in reality, for much of the U.S. Arctic air began pouring into the Rocky Mountains on December 3rd and snow began to accumulate heavily in the northern portion of such:Surface weather conditions at 7 a.m. ET on Tuesday, December 3rd. The cold air begins to filter in from Canada and a series of low-pressure systems develop along the frontal boundary. Heavy snow begins to fall in the northern Rockies. Surface weather conditions at 7 a.m. ET on Wednesday, December 4th. The arctic air has plunged southwards and expanded to both the West Coast and east into the Upper Midwest. Heavy snow begins to fall in Minnesota. An unusually intense low pressure of 985 mb is stationed over Colorado.Surface weather conditions at 7 a.m. ET on Thursday, December 5th Even colder air plunges into the U.S. as the front stalls out along a line from Texas to Ohio. The heavy snowfall in Minnesota tapers off. A sharp division between cold and warm temperatures exists on either side of the front. At one point during the day the temperature ranged from 89° in southern Texas to 14° in the state’s Panhandle. An ice storm develops later in the day from northeast Texas to Missouri. Surface weather conditions at 7 a.m. ET on Friday, December 6th. The high-pressure dome over Canada strengthens to 1047 mb reinforcing the cold air that has now plunged all the way to the Gulf Coast. Heavy snow and ice covers a large area from Texas to Ohio. A small low-pressure system slides down the Oregon coast bringing snowfall to sea level locations there.
The most damaging aspect of Winter Storm ‘Cleon’ was the ice that accumulated in portions of Texas, Oklahoma, Arkansas, Missouri, and Kentucky. All in all about 500,000 homes lost power at one point or another during the storm. Of the 8 storm-related deaths reported at least three were related to the ice. The accumulations were actually not so great (the thickest being 1.25” at Greenwood, Arkansas) but a huge area was affected. The heavy snow in Minnesota on December 4-6 was responsible for 4 fatalities as a result of automobile accidents.Snowfall Totals
Here is a list of the top reported snowfalls by state for winter storm ‘Cleon’:MINNESOTA:
35.2” Two HarborsIDAHO:
30.0” Blind Bull Summit (snotel)COLORADO:
30.0” Douglas PassMISSOURI:
13.0” Mt. VernonARKANSAS:
12.0” Calico Rock and Mt. ShermanSOUTH DAKOTA:
6.0” Wetherington and WyomingKENTUCKY:
5.3” West PaducahOKLAHOMA:
5.0” Bethany plus four other locations
Residents of Redding, California celebrate the lighting of the city's Christmas tree while a rare heavy snowfall dropped 5" on the city. Photo by Andreas Fuhrmann.
The snowstorm that hit Oregon on Friday dropped up to 3” at sea level on the coast at Newport. Up to 10” was measured in the Eugene-Corvallis area in the southern Willamette Valley. Snow also fell at low elevations in northern and central California including Redding where 5.0" was measured and also in Ukiah where little, if any, accumulation occurred.Snowfall map for Oregon on December 6th.
NWS-Portland.Cold (and warm) Temperature Reports
Bitterly cold temperatures were measured from California to Minnesota over the course of the past four days. Here are some of the lowest temperatures observed by state:MONTANA:
-43° at Chinook (Dec. 8)WYOMNIG:
-37° at Old Faithful and Daniel Fish Hatchery (Dec. 6)MINNESOTA:
-35° at Hibbing (Dec. 8)COLORADO:
-32° at Walden (Dec. 5)WISCONSIN:
-30° at Minong (Dec. 8)NORTH DAKOTA:
-29° at Hettinger (Dec. 7)SOUTH DAKOTA:
-27° at Aberdeen (Dec. 7)OREGON:
-27° at Lakeview (Dec. 8) their all-time record cold. Unofficial -39° at Christmas Valley AGRIMET MESONET site (Dec. 8)NEBRASKA:
-26° at Valentine and Gordon (Dec. 7)NEVADA:
-23° at Ely (Dec. 5) and Winnemucca (Dec. 8)CALIFORNIA:
-22° at Alturas (Dec. 8). Unofficial -26° at RAWS Ash Valley.IOWA:
-17° at Sheldon (Dec. 7)
In Utah a reading of -45° was measured at Peter Sinks on December 5th. This site, however, is a sink depression used to research cold air drainage so cannot be compared to the temperatures in the list above. Daily record lows were set at hundreds of locations from California and Oregon to the Upper Midwest and Plains states. Perhaps the most impressive of these was the 16° recorded at Napa, California on December 6th which was just 2° short of their all-time record cold temperature on record for any month (the record being 14° on December 22, 1990). Redding, California bottomed out at 20° on the 6th, just 4° short of their all-time record low of 16° set on four different occasions in the past.
Ahead of the front record warmth occurred. In fact, on December 6th, Savannah, Georgia reached 83°, the tying its warmest December monthly high on record (last set on Dec. 20, 1967) as did Tallahassee, Florida with a 84° reading on December 7th (last set on Dec. 16, 1971 and Dec. 14, 1931). Temperatures reached 81° as far north as southeastern Virginia (Petersburg).
More ice and snow is forecast to affect many of the same areas just hit by Cleon over the next couple of days (Sunday-Monday).IMPORTANT UPDATE ABOUT HILO, HAWAII HEAT RECORD:
This potential all-time heat tying record (94°) has been disallowed by the NWS-Honolulu office as a result of a sensor malfunction at the Hilo site on Nov. 28.
Christopher C. Burt