August 2020 National Storm Summary
NATIONAL STORM SUMMARY
AUGUST 2020
2-8: Hurricane Isaias made landfall near Ocean Isle Beach, NC, around 11:10 pm EDT on August 3, with maximum sustained winds near 85 mph. Heavy rain fell along and near the path of Isaias, which accelerated toward the north-northeast on August 4, passing east of Washington, D.C., but west of New York City. East of the center of circulation, wind damage and power outages were widespread across the Atlantic coastal plain as far north as New England..
Prior to the arrival of Hurricane Isaias, widely scattered but locally heavy showers dotted the Midwest and Northeast. On August 2, for example, daily-record amounts reached 5.89 inches in Reading, PA, and 4.79 inches in Milwaukee, WI. Reading also set a record for its wettest August day (previously, 5.04 inches on August 17, 1919). For Milwaukee, it was the wettest day since July 22, 2010, when 5.61 inches fell—and the wettest August day since August 6, 1986, when rainfall totaled 6.81 inches. Before midnight on August 3, unofficial wind gusts in coastal North Carolina included 99 mph at Federal Point and 87 mph at Oak Island. Minutes after moving inland, Isaias produced a wind gust to 73 mph in Wilmington, NC. Before daybreak on August 4, similar gusts were reported in North Carolina locations such as Jacksonville (69 mph); Manteo (68 mph); and Southport (66 mph). Later in the day on August 4, wind gusts included 78 mph at Farmingdale Airport, NY; 70 mph at New York’s JFK Airport; 67 mph at Wallops Island, VA; and 65 mph in Atlantic City, NJ. In Connecticut, gusts reached 62 mph in Bridgeport and 61 mph in Hartford. New England’s highest peak, Mount Washington, NH, clocked a southeasterly wind gust to 147 mph on the 4th, exceeding its monthly record of 142 mph set in August 1954. Meanwhile, daily record rainfall totals for August 4 topped the 4-inch mark in Pennsylvania communities such as Allentown (4.92 inches), Mount Pocono (4.39 inches), and Philadelphia (4.16 inches), as well as Wilmington, DE (4.48 inches). Other daily-record amounts for August 4 reached 3.92 inches in Albany, NY, and 3.61 inches in Richmond, VA. Following Isaias’ departure, Southeastern showers lingered. Record-setting rainfall totals for August 5 included 2.77 inches in Fort Myers, FL, and 2.55 inches in Asheville, NC. Richmond reported another daily-record sum (2.57 inches) on the 6th, boosting its August 1-8 rainfall to 9.72 inches. Late in the week, an increase in rainfall across the nation’s mid-section was accompanied by locally severe thunderstorms. During the evening of August 8, a wind gust to 74 mph was reported in Valentine, NE. Any showers in the West were highly localized, although Montague, CA, netted a daily-record total of 1.76 inches on August 5.
9-15: On August 10, a high-wind (derecho) event swept across the Midwest, covering some 770 miles in about 14 hours. A west-to-east swath across the central one-third of Iowa was among the hardest-hit areas, with widespread wind gusts of 75 to 100 mph recorded in communities such as Marshalltown, Ankeny, Des Moines, and Davenport. A broader area, generally stretching from eastern Nebraska into western Ohio, noted wind gusts in excess of 60 mph, along with pockets of large hail and isolated tornadoes. In Iowa’s peak-impact zone, satellite imagery immediate captured major vegetation changes, such as flattened or snapped corn stalks. Ironically, the derecho provided minimal relief in Midwestern drought areas, including parts of Iowa and Ohio. Much more significant rain fell in the Southeast.
Early-week precipitation was loosely associated with a Midwestern cold front. Daily-record amounts for August 9 reached 2.03 inches in Saint Louis, MO, and 1.53 inches in Grand Forks, ND. The following day, derecho-related winds hammered nearly the entire length of the Midwest. Peak wind gusts in Iowa were clocked to 99 mph in Marshalltown; 86 mph in Davenport; 78 mph in Ankeny; and 75 mph in Des Moines. Unofficial gusts topped 100 mph in several Iowa communities, including Midway (Linn County), near Cedar Rapids; Atkins (Benton County); and Le Grand (Marshall County). Elsewhere, August 10 gusts included 79 mph in Moline, IL; 72 mph in Chicago (Midway Airport), IL; 66 mph in Omaha, NE, and Benton Harbor, MI; and 61 mph in Indianapolis, IN. Meanwhile, locally heavy showers dotted the South for much of the week. Texarkana, AR, experienced its second-wettest day on record on August 12, when 7.43 inches fell. The previous wettest day on record in August was August 31, 2001, when 4.46 inches fell. Texarkana’s wettest day during any month remains May 28, 1998, when rainfall totaled 10.48 inches. Daily-record amounts topped 3 inches in several other Southern cities, including Jacksonville, FL (3.50 inches on August 10); Fort Smith, AR (3.44 inches on August 14); and Elizabeth City, NC (3.15 inches on August 15). Late in the week, thunderstorms across the upper Midwest led to record-setting totals for August 14 in Minnesota locations such as Saint Cloud (3.09 inches) and Hibbing (2.60 inches). In the West, late week thunderstorms—aided in development by remnant moisture from former eastern Pacific Hurricane Elida—produced numerous lightning strikes but not much rain. Still, daily-record totals in California included 0.08 inch (on August 13) in Paso Robles and 0.05 inch (on August 15) in Santa Maria. By mid-August more than two dozen wildfires—in various stages of containment—were active in California, with several other Western States also reporting a surge in fire activity.
16-22: In some areas of the country, thunderstorms produced gusty winds but little rain. On August 16, Dallas-Fort Worth (DFW), TX, reported a wind gust to 68 mph but received rainfall totaling only 0.29 inch. Still, it was the first measurable rainfall at DFW since July 29. A few days later, on August 20, Havre, MT, reported no rain but experienced a wind gust to 62 mph. August 1-22 rainfall in Havre totaled 0.01 inch (1 percent of normal). Meanwhile, spotty showers in the West were not enough to offset the effects of extreme heat, low humidity levels, and gusty winds. In California, daily-record rainfall totals included 0.10 inch (on August 17) in Alturas and 0.02 inch (on August 16) in downtown Sacramento. On August 20 in Arizona, Phoenix netted 0.90 inch—the first measurable rain in that location since July 24 and the wettest day since February 22—while Tucson collected 0.78 inch. Tucson had not experienced a wetter day since November 29, 2019, when 0.81 inch fell. In southwestern Utah, the first meaningful rain of the monsoon season fell on August 23-24, when Saint George measured 2.00 inches in a 24-hour period. Meanwhile, much more widespread showers affected the Southeast. On August 18, daily-record totals topped the 2-inch mark in Frankfort, KY (2.58 inches), and Alma, GA (2.38 inches). In Florida, month-to-date rainfall in Fort Myers climbed to 11.35 inches, aided by totals in excess of an inch on August 5, 9, 10, 11, 14, 21, and 22. Pockets of heavy rain affected other areas, including New England, the Pacific Northwest, the upper Midwest, and parts of Texas. Bangor, ME, netted a daily-record sum of 1.74 inches on August 18. Later, Quillayute, WA, noted a record-setting total (2.00 inches) for August 20. In Texas, daily-record amounts for August 22 reached 1.35 inches in San Angelo and 1.25 inches in Austin (Camp Mabry).
23-29: Category 4 Hurricane Laura came ashore on August 27 at 1:00 am CDT near Cameron, LA, delivering nearly unimaginable damage due to high winds and a coastal storm surge. At landfall, Laura featured sustained winds near 150 mph—the most powerful hurricane to make landfall in Louisiana since the 1856 Last Island (Isle Dernière) storm. Significant wind damage spread far inland and was especially notable in Lake Charles, LA, which had gusts above 130 mph. Heavy rain and gusty winds associated with Laura reached as far north as Arkansas, but the former hurricane rapidly weakened after turning eastward toward the mid-Atlantic Coast. Meanwhile, heavy showers spread from the Great Lakes region into the Northeast, but bypassed drought stricken sections of the western Corn Belt.
Prior to Laura’s arrival, Hurricane Marco briefly threatened the Gulf Coast and technically made landfall near the mouth of the Mississippi River as a decaying tropical storm on August 24. Rainfall loosely associated with Marco’s circulation soaked a few areas along the Gulf Coast, with Apalachicola, FL, experiencing its third-wettest day (7.85 inches on August 23) in the last 45 years. August 23-25 rainfall reached 6.15 inches in Pensacola, FL, and 10.20 inches in Apalachicola. Meanwhile, spotty thundershowers affected the West, where daily-record totals included 0.59 inch (on August 23) in Desert Rock (Mercury), NV, and 0.27 inch (on August 26) in Challis, ID. Saint George, UT, received 2.00 inches of rain in a 24-hour period on August 23-24. Around mid-week, locally heavy showers in the Great Lakes region led to daily-record totals in locations such as Milwaukee, WI (2..14 inches on August 25), and Sault Sainte Marie, MI (1.57 inches on August 26). Hurricane Laura roared ashore in southwestern Louisiana in the dead of night on August 27, resulting in measured wind gusts to 133 mph in Lake Charles and 127 mph at Calcasieu Pass. The water level at the tide station at Calcasieu Pass climbed 7.07 feet above flood stage as Laura moved ashore, the fourth-highest surge on record behind 11.00 feet with Hurricane Rita on September 24, 2005; 9.30 feet with Hurricane Audrey on June 27, 1957; and 7.90 feet with Hurricane Ike on September 13, 2008. Coastal Texas, which escaped a direct hit, experienced wind gusts to 90 mph at Texas Point National Wildlife Refuge and 72 mph in Beaumont-Port Arthur. During the morning of the 27th, hurricane-force wind gusts were reported in Louisiana communities such as Alexandria (86 mph), De Ridder (82 mph), New Iberia (76 mph), and Vernon (74 mph). Farther inland, tropical storm-force gusts included 65 mph in Shreveport, LA; 57 mph in El Dorado, AR; 56 mph in Monroe and Lafayette, LA; and 53 mph in Gulfport, MS. Although much wind and rainfall information in the areas hardest hit by Laura was lost, daily record precipitation totals for August 27 in Arkansas included 4.18 inches in North Little Rock, 3.74 inches in El Dorado, 2.79 inches in Pine Bluff, and 2.59 inches in Texarkana. Monthly rainfall totaled 19.70 inches near Big Fork, Polk County, AR, breaking a state record for August (previously, 19.55 inches in Hardy, Sharp County, in 1915). Late in the week, heavy showers returned across portions of the Great Lakes States and spread into the Northeast. Record-setting totals for August 28 reached 2.85 inches in Pittsburgh, PA, and 2.83 inches in Detroit, MI. In West Virginia, daily record amounts included 2.20 inches (on August 28) in Wheeling and 2.04 inches (on August 29) in Elkins. Elsewhere on the 29th, rainfall across the central and southern Plains resulted in daily-record amounts in Russell, KS (1.58 inches), and Amarillo, TX (1.41 inches). With warmth dominating the country, daily-record highs were scattered across several regions.
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