NATIONAL STORM SUMMARY

DECEMBER 2023

3-9:  Heavy rain and melting snow sparked Northwestern flooding, especially in western sections of Washington and Oregon. Warm, wet weather extended as far inland as the northern Rockies and northern Intermountain West.

Late in the week, a potent cold front delivered suddenly unsettled weather from the Mississippi Valley eastward. Cool air trailing the front tempered a winter warm spell, while rain in the vicinity of the front totaled 2 inches or more in the southern Appalachians and environs. (Additional heavy rain fell in the eastern U.S. on Sunday, December 10.) The cold front also sparked a severe weather outbreak, which peaked across the South on December 9, with more than two dozen tornadoes and several fatalities reported.

Sudden warmth in the Northwest melted lower- and middleelevation snow that had fallen in late November and early December, adding runoff to already rain-swollen streams and rivers. On the night of December 5-6, the Skagit River at Concrete, WA, rose 5.83 feet above flood stage—the highest water level at that gauge site since mid-November 2021. In advance of the flooding, daily-record rainfall totals for December 4 in western Washington included 4.19 inches in Quillayute and 2.93 inches in Hoquiam. Daily records were set on December 5 with totals of 2.96 inches in Olympia, WA, and 2.52 inches in Astoria, OR. During the first 10 days of December, rainfall topped the 8-inch mark in Quillayute (8.95 inches), Olympia (8.75 inches), and Hoquiam (8.22 inches). Eventually, precipitation spread eastward, with Bismarck, ND, reporting a 2.5-inch snowfall on December 8. Meanwhile, cold weather lingered across northern New England, accompanied by a burst of snow. In Maine, Bangor received a daily-record snowfall of 6.4 inches on December 4.

Late in the week, showers and thunderstorms erupted across the lower Mississippi Valley and the mid-South. On December 9, a pair of deadly tornadoes touched down in Tennessee, with the first—an EF3 with estimated winds near 150 mph and a path length of more than 11 miles—tracking from Montgomery County, TN, where three fatalities occurred, into Todd County, KY. The second deadly tornado, an EF2 with estimated winds near 125 mph, also resulted in three fatalities (in Davidson County, TN) while traversing a nearly 30-mile path from about 5 miles north of Nashville into Sumner County.

10-16: The week began and ended with heavy precipitation in the Atlantic Coast States. The initial storm system, which primarily struck on December 10-11, featured a rainto-snow transition in portions of the middle and northern Atlantic States. The second storm, which arrived on December 16-17, delivered heavy rain from Florida northward. Before reaching the East, the late-week system also produced significant precipitation in the southcentral U.S. On the central and southern Plains, rain— or a mix of rain and wet snow.  Storm-total precipitation topped 2 inches on the High Plains from parts of northern Texas into southwestern Kansas. Much of the remainder of the country received little or no precipitation. Mostly light rain and snow showers were observed in the Midwest and Northwest, but dry weather prevailed from California and the Great Basin to the northern Plains.

The week began with heavy rain, or rain changing to snow, along the Atlantic Coast. The 10th was the wettest December day on record in Richmond, VA, where 2.73 inches fell. Previously, Richmond’s wettest December day had occurred in 2008, when 2.62 inches fell on the 11th. Elsewhere in the East on December 10, daily-record totals ranged from 2 to 3 inches in locations such as Greensboro, NC (2.86 inches); Bridgeport, CT (2.75 inches); New York’s JFK Airport (2.38 inches); and Danville, VA (2.09 inches). The following day, December 11, daily-record totals in New England included 1.81 inches in Bangor, ME, and 1.75 inches in Boston, MA. Despite some wet snow at storm’s end, streaks of not experiencing a calendar-day snowfall of an inch or greater continued in several mid-Atlantic cities. In Washington, DC, and Richmond, VA, a 1-inch snowfall last occurred on January 16, 2022, with streaks reaching 699 days by December 16, 2023. In Maryland, Baltimore’s streak—which started on January 29, 2022—reached 687 days. Through December 16, other “snowless” streaks—no calendar-day totals of an inch or greater— climbed to 686 days in Philadelphia, PA, and 671 days at New York’s Central Park. Farther west, consecutive daily-record precipitation totals occurred on December 13-14 in locations such as Borger, TX (1.01 and 1.72 inches, respectively), and Guymon, OK (1.25 inches both days). Meanwhile in Colorado, December 13-14 snowfall totaled 5.4 inches in Pueblo and 4.1 inches in Colorado Springs. However, mostly rain fell as far north as the upper Great Lakes region, where— on December 15—Duluth, MN, noted a daily-record precipitation sum of 0.80 inch, including snowfall totaling 0.2 inch. At week’s end, an intensifying low-pressure system moving northward from the Gulf of Mexico delivered heavy rain and gusty winds across Florida. Leesburg, FL, experienced its wettest December day on record, with 2.97 inches falling on the 16th. Previously, Leesburg’s wettest December day occurred in 1983, with 2.38 inches falling on the 12th. Elsewhere in Florida, daily-record rainfall totals for December 16 reached 3.06 inches in Melbourne, 2.57 inches in Daytona Beach, 2.46 inches in Sarasota-Bradenton, and 2.33 inches in Orlando. More details on this storm, which moved northward near the Atlantic Seaboard on December 17-18, will appear next week.

17-23: Early in the week, an Atlantic coastal storm pounded portions of the East Coast States with heavy rain, high winds, and pounding surf, with areas from the Carolinas to New England taking the most significant hit. Once-in-ageneration flooding struck parts of Maine, with water rising to the highest levels since April 1987 along portions of the Androscoggin and Kennebec Rivers. In addition, tens of thousands of customers in Maine lost electrical service at the height of the storm.

A storm system passing near the Atlantic Seaboard early in the week generated an impressive storm surge. On December 17 in South Carolina, Charleston Harbor experienced its fourth-highest water level on record—2.86 feet above flood stage— behind only the hurricane-induced high-water marks of September 22, 1989 (Hugo); August 11, 1940 (unnamed hurricane); and September 11, 2017 (Irma). Meanwhile, daily-record rainfall totals for the 17th ranged from 3 to 4 inches or more in locations such as Lumberton, NC (4.08 inches); downtown Charleston, SC (3.92 inches); Wilmington, NC (3.23 inches); and Savannah, GA (3.16 inches). For Lumberton, it was the wettest December day on record, topping 3.30 inches on December 26, 1943. Downtown Charleston also had a historically wet day, edging the monthly record of 3.82 inches, originally set on December 18, 2009. For the second time this month, Richmond, VA, experienced its wettest December day on record. Richmond netted 2.73 and 2.74 inches, respectively, on December 10 and 17. Prior to this year, Richmond’s wettest December day had occurred in 2008, when 2.62 inches fell on the 11th. In North Carolina, peak wind gusts on December 17 were clocked to 66 mph on Cherry Point and 64 mph at Billy Mitchell Airport, near Cape Hatteras. The following day, the 18th, Northeastern peak gusts included 81 mph in Eastport, ME; 71 mph in Bangor, ME; 68 mph in Boston, MA; and 63 mph in Providence, RI. On December 17-18, Salisbury, MD, netted 5.18 inches of rain and reported a wind gust to 59 mph. With 4.04 inches on the 18th, it was also Salisbury’s wettest December day (previously, 3.56 inches on December 18, 1977). Elsewhere on the 18th, daily-record totals included 3.00 inches in Mount Pocono, PA; 2.83 inches in Worcester, MA; 2.75 inches in Newark, NJ; 2.73 inches in Concord, NH; 2.52 inches in Bangor, ME; and 2.43 inches in Providence, RI. Farther west, storminess clipping California produced daily-record totals on December 18 in Redding (2.45 inches) and Red Bluff (2.05 inches). By December 20, heavy showers shifted into southern California, where daily-record amounts reached 1.68 inches in Santa Maria and 1.37 inches in Paso Robles. Southern California’s wet weather continued through December 21, when dailyrecord amounts included 2.78 inches in Oxnard and 2.60 inchesin Santa Barbara. Parts of southern Arizona received more than an inch of rain on December 22-23, with 2-day totals reaching 1.27 inches in Tucson, 1.19 inches in Safford, and 1.15 inches in Nogales. Farther east, lateweek, daily-record amounts included 0.77 inch (on the 22nd) in Ottumwa, IA, and 0.57 inch (on the 23rd) in Pueblo, CO.

A surge of warmth accompanied the early-week Eastern storminess, with daily-record highs for December 18 soaring to 64°F in Hartford, CT; 63°F in Boston, MA; 62°F in Concord, NH, and 61°F in Bangor, ME. Meanwhile, warmth in the Pacific Coast States expanded eastward. In California, daily-record highs rose to 78°F (on the 17th) in Santa Barbara and 71°F (on the 18th) in Hanford. By December 19 on the High Plains, daily-record highs topped the 65-degree mark in locations such as Goodland, KS (68°F); Denver, CO (67°F); and Sidney, NE(66°F). During the second half of the week, rampant warmth prevailed in advance of a Western storm system. On December 21, Phoenix, AZ, logged a daily-record high of 78°F. From December 20- 22, Livington, MT, tallied a trio of daily-record highs (56, 57, and 56°F). At week’s end, warmth shifted further into the Midwest, where dailyrecord highs for the 23rd reached 56°F in Aberdeen, SD, and 52°F in Waterloo, IA.

24-30: Widespread precipitation fell from the Plains eastward, but causing regional issues due to blizzard conditions (in the north-central U.S.), accumulations of freezing rain (in North Dakota and environs), and flash flooding (in parts of the East). The stormy weather also hampered holiday travel, especially in areas affected by snow, ice, or flooding.

Western storminess remained predominantly offshore, powerful lowpressure systems over the eastern Pacific Ocean generated massive waves, some of which inundated coastal communities. Parts of coastal California endured the brunt of the pounding surf, which lasted for several days.

the holidays, a slow-moving, unusually wet weather system unfolded across the northern Plains and upper Midwest. December 23-27 precipitation totals reached 3.36 inches in Sisseton, SD; 2.83 inches in Fargo, ND; and 2.40 inches in St. Cloud, MN. The storm helped to propel all three locations to their wettest December on record, with 3.61 inches (602 percent of normal) in Sisseton, 3.35 inches (372 percent) in St. Cloud, and 3.00 inches (337 percent) in Fargo. In those locations, only a small amount of the precipitation fell as snow, with totals reaching 1.8 inches in Sisseton, 0.6 inch in Fargo, and a trace in St. Cloud. However, December 24-26 snowfall reached at least 5 inches in several locations in Nebraska, including North Platte (7.0 inches) and Valentine (5.4 inches), as well as many places in South Dakota. Huron, SD, received 6.5 inches of snow from December 24- 26, while exactly 5 inches fell in Aberdeen and Mitchell. Christmas Day featured wind gusts to 50 mph or higher in several communities, including Valentine (55 mph) and Aberdeen (50 mph). Meanwhile, heavy showers in portions of the Gulf Coast States boosted dailyrecord totals for the 24th above 2 inches in Beaumont-Port Arthur, TX (2.65 inches), and New Orleans, LA (2.05 inches). It was the wettest December 25 on record in Florida locations such as Fort Pierce (1.45 inches) and Vero Beach (1.08 inches). Significant rain fell in the Southeast on December 26, when daily-record totals reached exactly 2.74 inches in Marathon, FL, and Athens, GA. On December 27, Eastern daily-record amounts included 3.02 inches in Wilmington, NC; 2.05 inches in Allentown, PA; and 1.46 inches in Richmond, VA. Allentown (8.62 inches) and Richmond (8.87 inches) also noted record-high December precipitation totals. Finally, by December 28, rain began to exit the East Coast. However, Islip, NY—with 3.04 inches of rain on the 28th—experienced its wettest December day, surpassing 2.65 inches on December 11, 1992.

Jim G. Munley, jr.
http://www.jimmunleywx.com