Nov 25, 2020, 10:51:13 AM11/25/20
NATIONAL STORM SUMMARY
4-10: Category 2 Hurricane Delta made landfall on October 9 at 6:00 pm CDT with sustained winds of 100 mph near Creole, LA, located in the same parish (Cameron) as the town of Cameron, where Hurricane Laura moved ashore 43 days earlier. Shortly before landfall, the tide station at Calcasieu Pass, LA, reported a water level of 7.40 feet, the sixth-highest surge on record. During Laura, a height of 11.07 feet was recorded at that location. Once inland, Delta quickly weakened, although heavy rain spread across the Southeast and stretched as far north as the Tennessee Valley.
During the evening of October 9, hurricane-force wind gusts (74 mph) or greater were common across southern and central Louisiana. Lake Charles, LA, slammed by wind gusts in excess of 130 mph during Hurricane Laura, endured a gust to 96 mph during Hurricane Delta. Elsewhere in Louisiana, gusts included 90 mph in New Iberia and at Calcasieu Pass; 81 mph in Jennings; and 75 mph in Lafayette and Opelousas. Hurricane-force winds extended westward to the Texas state line, where a gust to 100 mph was clocked at Texas Point National Wildlife Refuge. On the night of October 9-10, tropical storm-force wind gusts (39 to 73 mph) were common across the southern Mississippi Delta and environs. In Mississippi, gusts to 54 mph were reported early on October 10 in Greenville and Jackson. Delta’s rain totaled 10 to 18 inches in parts of southwestern and central Louisiana, leading to major flooding in the Calcasieu River basin. On the 9th, official rainfall totals included 9.53 inches in Lake Charles and 8.62 inches in Alexandria. For Lake Charles, it was the wettest October day on record (previously, 7.20 inches on October 27, 1970) and the wettest day during any month since May 16, 1980, when 15.67 inches fell. Farther east, the 10th was the wettest October day on record in Greenville, MS, where 5.18 inches fell (previously, 4.58 inches on October 17, 1984). Flooding rains also soaked the southern Appalachians and adjacent foothills, where 4- to 8-inch totals were common. In Atlanta, GA, where 4.55 inches fell on October 10, it was the wettest day since July 11, 2005, and the wettest October day since October 4, 1995, when 6.68 inches fell. In other areas of the country, rainfall was scarce. Through week’s end, Indianapolis, IN, experienced 53 consecutive days (August 19 – October 10) with rainfall totaling less than 0.10 inch. Indianapolis’ previous record of 47 such days was set from June 1 – July 17, 2012. Locally severe thunderstorms swept across the Northeast on October 7, when hail was reported in Binghamton and Syracuse, NY. Elsewhere in New York, Albany reported an October record with a wind gust to 67 mph. Meanwhile in the Northwest, a precipitation total of 0.62 inch in Stanley, ID, on October 10 set a record for the date.
11-17: Early in the week, remnant moisture from former Hurricane Delta—interacting with a cold front—exited the middle and northern Atlantic States.
Following the passage of Hurricane Delta, flooding continued for several days in Louisiana’s Calcasieu River basin and neighboring areas. On October 11, the second-highest crest on record occurred at Bayou Cocodrie near Clearwater, LA. The record crest in that location remains 7.72 feet above flood stage on May 18, 1953; the 2020 crest was 5.17 feet above flood stage. Similarly, the Calcasieu River at White Oak Park, LA, crested 7.41 feet above flood stage on October 14—the fifth-highest water level on record. Higher crests in White Oak Park were observed on May 21, 1953; July 2, 1989; August 10, 1940; and September 2, 2017. Farther east, heavy rain lingered in the Carolinas, where daily-record totals for October 11 reached 3.95 inches in Lumberton, NC; 2.91 inches in Charlotte, NC; and 1.75 inches in North Myrtle Beach, SC. Two days later, a separate weather system produced record-setting amounts for October 13 in Maine locations such as Millinocket (1.73 inches) and Bangor (1.44 inches). Millinocket and Bangor also received more than an inch of rain on October 17. Meanwhile in Indianapolis, IN, a record-setting streak of 57 days (August 19 – October 14) with daily amounts of less than one-tenth of an inch of precipitation ended with a 0.18-inch total on October 15. As the week progressed, Northern precipitation expanded and intensified. In the Northwest, daily-record amounts for October 13 included 0.68 inch in Kalispell, MT, and 0.55 inch in Stanley, ID. By October 16- 17, widespread snow developed. In fact, daily-record snowfall totals for October 17 included 1.7 inches in East Rapid City, SD, and 1.6 inches in Marquette, MI. In Montana, record-setting totals for the 17th reached 6.6 inches in Helena, 5.2 inches in Billings, and 4.2 inches in Great Falls. The following day, October 18, was the snowiest October day on record in Great Falls, where 8.2 inches fell (previously, 6.6 inches on October 13, 1975).
18-24: Locally heavy precipitation in the form of rain and snow fell in the Midwest. mostly dry weather persisted through week’s end from California to the central and southern High Plains, maintaining stress on rangeland, pastures, and winter wheat.
During the 10 days from October 16-25, snowfall in Montana totaled 28.0 inches in Great Falls and 25.4 inches in Helena. On October 17- 18, Great Falls received 10.3 inches of snow in a 24-hour period; the previous October record in that location had been 8.3 inches on October 3-4, 1957. In addition, Great Falls set an October record with 10 inches of snow on the ground on October 19; the previous earliest depth of 10 inches or greater had been achieved on November 9, 2012. Midwestern weekly (October 18-24) snowfall totals included 12.3 inches in Mobridge, SD; 10.2 inches in Aberdeen, SD; 8.7 inches in Minneapolis-St. Paul (MSP), MN; and 7.2 inches in Eau Claire, WI. October 20 snowfall totals reached 7.9 inches at MSP and 6.9 inches in Eau Claire; in the latter location it was the snowiest October day on record, surpassing 5.0 inches on October 18, 1925. Another round of heavy snow on October 22 dumped daily-record amounts in South Dakota locations such as Aberdeen (7.2 inches), Mobridge (5.9 inches), and Sisseton (4.7 inches). Helena, MT, reported a daily-record snowfall of 8.7 inches on October 23. Elsewhere on the 23rd, Spokane, WA, experienced its snowiest October day; the 6.9-inch total exceeded 5.9 inches on October 22, 1957. Farther east, locally heavy rain affected several areas. On October 19, daily-record totals reached 3.93 inches in Paducah, KY, and 1.49 inches in Cape Girardeau, MO. Three days later, on October 22, daily-record Midwestern totals included 3.07 inches in Traverse City, MI; 2.94 inches in Waterloo, IA; and 2.72 inches in Green Bay, WI. It was the wettest October day on record in Traverse City (previously, 2.30 inches on October 23, 2017) and Waterloo (previously, 2.65 inches on October 29, 1961). Toward week’s end, heavy showers shifted southward; daily-record amounts totaled 3.36 inches (on October 23) in Monroe, LA, and 1.32 inches (on October 24) in Knoxville, TN.
25-30: Category 2 Hurricane Zeta moved ashore in southeastern Louisiana near Cocodrie around 4 pm CDT on October 28, bearing sustained winds of 110 mph. Zeta’s rapid forward motion limited flood impacts, but tropical storm-force winds (39 to 73 mph) spread northeastward from the central Gulf Coast across the southern Appalachians to the middle Atlantic Coast.
A system caused heavy rain from the mid-South into the Ohio Valley, in part due to interaction with the remnants of Zeta.
In southern California, gusty winds accompanied the surge of colder air, contributing to the rapid spread of a couple of wildfires.
Oklahoma City (and other areas in central Oklahoma) also experienced a significant ice storm, with precipitation totaling 4.51 inches from October 26- 28. Amarillo, TX, received 7.4 inches of snow from October 26-29, with a peak depth of 5 inches on the 29th. Farther east, daily-record rainfall totals for October 28 reached 3.78 inches in Hattiesburg, MS; 3.02 inches in Batesville, AR; 2.93 inches in New Orleans, LA; and 2.87 inches in Huntsville, AL. On October 28, peak wind gusts associated with Hurricane Zeta were clocked to 104 mph in Waveland, MS; 95 mph in Gulfport, MS, and 87 mph in Belle Chasse, LA. Elsewhere in Louisiana, gusts to 68 mph were noted in Boothville and Slidell, while New Orleans reported 71 mph. On October 29 in Georgia, gusts included 56 mph in Columbus and 55 mph in Rome. Daily-record rainfall totals for the 29th reached 3.66 inches in Evansville, IN; 2.67 inches in Clarksburg, WV; and 2.28 inches in Lynchburg, VA. Farther north, snow ended early in the week, capping an exceptionally stormy period across the northern and central Plains and upper Midwest. Still, October 25 featured daily-record snowfall amounts in Cheyenne, WY (14.0 inches); Pueblo, CO (7.8 inches); Sioux City, IA (4.2 inches); and Norfolk, NE (3.7 inches). With a 4.1-inch snowfall on the 25th, Grand Junction, CO, reported its snowiest October day (previously, 3.4 inches on October 24, 1975). Snow lingered in some areas into October 26, when daily-record amounts reached 7.8 inches in Alamosa, CO, and 1.3 inches in Wichita, KS. From October 16-25, snowfall totaled 28.0 inches in Great Falls, MT, and 9.3 inches in Minneapolis-St. Paul, MN. Both totals set respective October records (previously, 18.5 inches in 1925 in Great Falls and 8.2 inches in 1991 in Minneapolis). October snowfall records were also broken in locations such as Marquette, MI (22.1 inches); Timber Lake, SD (18.4 inches); and Eau Claire, WI (8.4 inches). On October 30, snow blanketed parts of the Northeast, where Boston, MA (4.3 inches), and Providence, RI (1.6 inches), reported single-day records for October. Elsewhere, highs winds in southern California on October 26 fanned the newly sparked Silverado and Blue Ridge Fires; collectively, those wildfires consumed more than 26,000 acres of vegetation and were fanned by winds that reached 88 mph in Fremont Canyon.