From James Munley@21:1/5 to All on Wed Feb 17 17:36:14 2021
NATIONAL WEATHER SUMMARY
3-9: Large sections of the country, including much of the Southwest, Plains, Midwest, and Northeast, experienced dry weather. Late in the week, however, a developing storm system across southern sections of the Rockies and Plains produced some snow, much
of which fell on January 10.
Arctic air was again blocked from reaching the United States, resulting in near- or above-normal temperatures across most of the country. Pockets of cooler-than normal conditions were mostly confined to the central Rockies and environs. The warmest
weather, relative to normal, again affected the nation’s northern tier. Weekly temperatures averaged 10 to 20°F above normal from northern Montana to Lake Superior, including parts of the Dakotas. With Arctic air bottled up, far away from the Lower 48
States, there were few temperature records set in early January. In western Montana, the Bozeman Yellowstone International Airport posted a daily record high of 50°F on January 3. Bozeman had not attained a 50-degree reading in January since January 26,
2015. On January 4 in Minnesota, daily-record highs included 39°F in Hibbing and 38°F in International Falls. Late in the week, dry air settled across California and the Southwest, contributing to large diurnal temperature variations. On January 8,
Santa Barbara, CA, notched a daily-record high of 79°F—a sharp rise from that morning’s low of 36°F. Similarly, Ramona, CA, began a string of days with high temperatures above 70°F, starting on the 6th, but also notched a daily record-tying low of
24°F on January 9.
Extremely tranquil weather prevailed in many areas of the country during the first 9 days of January. From January 1-9, no measurable snow fell in locations such as Des Moines, IA, and Minneapolis-St. Paul, MN, although upper Midwestern snow remained on
the ground in the wake of late-December storms.
10-16: Despite the storminess, atypically mild weather dominated the North, continuing a trend that developed late last year. Weekly temperatures averaged 10 to 20°F above normal across large sections of the northern Plains and upper Midwest, with
warmth extending eastward into New England. Above-normal temperatures also covered the Far West. In contrast, chilly conditions across the South held temperatures more than 5°F below normal in many locations.
The week’s first surge of significant warmth occurred in advance of the Northern storm. January 12-13 featured consecutive daily-record highs in Oregon location such as Roseburg (63 and 62°F, respectively) and Pendleton (61 and 63°F). Warmth also
overspread the northern Plains, where record-setting highs for January 14 included 66°F in Sheridan, WY; 58°F in Havre, MT; and 55°F in Dickinson, ND. During the second half of the week, temperatures soared across California and environs. By January
15, a monthly record was set in Vista, CA, where the high temperature climbed to 94°F (previously, 90°F on January 31, 2003, and January 29, 2018). Elsewhere in California on the 15th, monthly records were tied in Camarillo (94°F), El Cajon (93°F),
and San Diego (88°F). San Diego previously attained 88°F on January 10, 1953. On the 16th, Death Valley reached the 90-degree mark in January for the first time on record; the previous monthly record had been 87°F on January 8, 1962, and January 25,
2015. The week ended (from January 14-16) with a trio of daily-record highs in Yuma, AZ (81, 81, and 84°F). Consecutive daily-record highs occurred on January 15-16 in California locations such as Palm Springs (89 and 90°F, respectively) and downtown
Los Angeles (88°F both days).
17-23: Across California, the Great Basin, and the Southwest, cool, showery weather replaced previously warm, dry conditions.
Most of the country continued to experience near- or above-normal temperatures, although warmth across the North was less pronounced compared to recent weeks. Still, weekly temperatures averaged at least 5 to 10°F above normal in several areas,
including large sections of the Plains and from the western Gulf Coast region into the lower Mississippi Valley. Pockets of cooler-than-normal conditions were generally limited to the Rockies, Southeast, Pacific Northwest, and upper Midwest. As the week
progressed, however, notably cooler air overspread the West. Sub-zero temperatures were mostly limited to the Rockies and the nation’s northern tier from North Dakota and the upper Mississippi Valley to northern New England. From January 16-20,
lingering warmth in Stockton, CA, resulted in five consecutive daily-record highs (72, 72, 78, 72, and 68°F). With its January 18 high of 78°F, Stockton also set a monthly record (previously, 75°F on January 9, 1953). Elsewhere in California,
consecutive daily-record highs occurred on January 17-18 in locations such as Ukiah (78 and 80°F, respectively) and downtown San Francisco (74 and 76°F). The last time Ukiah attained an 80-degree reading in January was 1984, when a high of 82°F
occurred on January 27.
Windy weather accompanied a surge of colder air across the northern Plains. On January 19, a gust to 74 mph was clocked in Cut Bank, MT. Despite the colder conditions across the northern Plains—and later the Midwest and East— temperatures were not
extreme by historical standards. Duluth, MN, noted three sub-zero readings during the week (and for the month to date), including a low of -6°F on January 22. However, three sub-zero temperatures in Duluth during the first month of the year would
represent the second-lowest January total on record (tied with 1889, 1891, and 1932), behind one such day in 2006. Elsewhere, sharply cooler conditions in California resulted in Santa Ana reporting a January 23 high of 53°F, down from 94°F on January
24-30: California’s most powerful storm of the season to date delivered drought-easing precipitation, including heavy mountain snow, but caused local flooding and landslides. Impacts from the multi-day storm system extended beyond California, reaching
into the Northwest, Southwest, and the Great Basin. Late in the week, the Western storm finally turned eastward, resulting in wintry precipitation in the Midwest and rain showers across the South.
Mostly dry weather covered other areas of the country, including the northern Plains, upper Midwest, and southern sections of Florida and Texas. Meanwhile, colder air settled across large parts of the country, although lingering warmth covered much of
the South. Weekly temperatures averaged at least 5 to 10°F below normal in several areas, including portions of the Pacific Coast States and the Southwest, as well as snow-covered sections of the central Plains. Cold weather (as much as 5 to 10°F below
normal) also gripped the middle and northern Atlantic States, excluding Maine. Although sub-zero temperatures were common along and north of a line from the central High Plains to southern New England, frigid conditions (below -20°F) were mostly limited
to northern portions of Minnesota and North Dakota. In contrast, weekly readings averaged 5 to 10°F or more above normal in the western and central Gulf Coast States.
Despite a surge of cold air across the West, as well as several other regions, few temperature records were set. In advance of the earlyweek storm, Southern daily-record highs included 76°F in Tupelo, MS, and 73°F in North Little Rock, AR. In Florida,
a brief spell of record-setting warmth produced January 27 highs of 86°F in West Palm Beach and Fort Pierce. Meanwhile, cool air was already in place across the West before stormy weather arrived. Daily-record lows for January 25 dipped to 10°F in Twin
Falls, ID, and 36°F in downtown Oakland, CA. Late in the week, however, mild weather developed across northern sections of the Rockies and High Plains. Record-setting highs for January 29 rose to 63°F in Sidney, NE, and 56°F in Worland, WY. Colder air
settled across much of Alaska, although mild weather lingered in the southwestern part of the state.