NATIONAL STORM SUMMARY

AUGUST 2026

2-8: scattered to widespread Eastern showers further eased any remaining drought and generally benefited pastures and immature summer crops. Weekly rainfall totals of 2 to 4 inches or more were common throughout the Atlantic Coast States.

Northeastern downpours on the 2nd included the wettest August day on record in Williamsport, PA, where 5.28 inches fell. Williamsport’s wettest August day had been August 24, 1933, with 5.22 inches. The only 4 wetter days in Williamsport had been associated with tropical cyclones: Agnes on June 22, 1972; Lee on September 7, 2011; Dennis on September 7, 1999, and Ivan on September 17, 2004. Northeastern wetness lingered into August 3, when daily record totals included 3.59 inches in Hartford, CT; 2.75 inches at New York’s JFK Airport; and 2.52 inches in Providence, RI. Later, mid-week thunderstorms swept eastward from the Midwest, leading to record-setting totals for August 5 in Alpena, MI (1.73 inches), and Elkins, WV (1.56 inches). On August 6, during a southward shift in heavy showers, daily-record amounts reached 3.28 inches in Columbia, MO; 2.78 inches in Jackson, MS; and 1.91 inches in Daytona Beach, FL. Farther west, however, the surface elevation of Lake Mead on August 6 fell to a record-low level since the reservoir above Hoover Dam was filled in the late 1930s. The previous record low elevation of 1040.58 feet had been set on July 28, 2022. Late in the week, spotty showers mainly affected the South, East, and Midwest. Selected daily-record totals included 2.12 inches (on August 7) in Harrison, AR, and 1.22 inches (on August 8) in Burlington, VT. Alaska’s generally wet summer continued, although warm, mostly dry weather prevailed in some remote northern locations. In south-central Alaska, Talkeetna completed its wettest July on record, with rainfall totaling 10.59 inches (previously, 8.96 inches in 2003), followed by 2.14 inches during the first 6 days of August. Farther north, McGrath received 1.46 inches during the week, aided by a daily-record sum of 0.90 inch on August 3. Meanwhile in Hawaii, windward showers and leeward dryness continued into early August. Honolulu, Oahu, received only a trace of rain during the first 8 days of August, following a record-tying low July total of 0.02 inch (4 percent of normal).

9-15: The complex interaction between the North American monsoon circulation and several cold fronts led to excessive rainfall (locally 4 to 12 inches or more) across the northern periphery of a ridge of high pressure parked over the south-central and southeastern U.S. The band of heaviest rain stretched from parts of Iowa to the central Appalachians, with locally major flooding developing across east-central Indiana. By week’s end, minor to moderate flooding broadly encompassed central sections of Illinois and Indiana. Meaningful rainfall extended to the northwestern half of the Plains. Daily-record totals included 1.28 inches (on the 14th) in Cut Bank, MT; 1.26 inches (on the 13th) in Casper, WY; and 1.23 inches (on the 15th) at Lake Yellowstone, WY. Farther east, multiple thunderstorms pounded the Midwest, with daily-record totals being set in locations such as Norfolk, NE (3.30 inches on the 13th); Grand Rapids, MI (2.55 inches on the 9th); and Dayton, OH (2.19 inches on the 11th). On August 13, the White River at Muncie, IN, rose to its highest level since January 1937 and crested just 3.96 feet below the March 1913 high-water mark. Heavy showers extended as far south as Kentucky, where Lexington measured a daily-record sum (2.59 inches) for August 12. During the second half of the week, rainfall intensified across the northern half of the Plains. With a 3.04-inch total on August 15, Alliance, NE, experienced its wettest day on record (previously, 2.81 inches on August 30, 1963). Late-week showers also dotted the Southeast, where Gainesville, FL, netted a daily-record sum of 2.12 inches on August 14.

Significant Alaskan precipitation was scarce, although King Salmon received rainfall totaling 1.26 inches from August 12-15. Farther south, Hurricane Lala grazed Hawaii on August 15, passing about 50 miles south of South Point and slamming the Big Island with heavy rain bands that caused extensive flooding and debris flows. Event-total rainfall ranged from 24 to 36 inches at several Big Island locations, with 43.55 inches measured at Laupahoehoe. Hilo officially received 14.18 inches from August 14-16—and clocked an easterly wind gust to 56 mph on the middle date. Several hurricane-force wind gusts were reported on the Big Island and in Maui County. Big Island gusts reached 140 mph on August 15 at the 13,803-foot Mauna Kea summit; 84 mph at Kohala Ranch; and 73 mph at the Kona Airport. Gusts at other locations included 67 mph at Kaneohe, Oahu; 62 mph at Kahului, Maui; and 61 mph at Molokai Airport.

16-22: For the second week in a row, monsoon-related moisture interacting with Northern cold fronts delivered heavy showers (1 to 4 inches or more) and locally severe thunderstorms from the central Plains to the middle Atlantic Coast. Wet weather perpetuated lowland flooding in parts of the eastern Corn Belt but further eased drought on the central Plains.

Impacts from the previous week’s Midwestern storms lingered into the new week, with tens of thousands of electrical customers remaining without power in northwestern Indiana and flood crests moving through creeks and streams to larger rivers in central sections of Illinois and Indiana. The August 11 derecho that swept from eastern Iowa to the central Appalachians and caused widespread power outages had produced official wind gusts to 99 mph in Gary, IN, and 82 mph in Columbus, OH, along with more than 1,000 reports of wind damage. Meanwhile, the White River at Noblesville, IN, achieved a record crest on August 15, topping the March 1913 high-water mark by 0.8 foot. As the week began, heavy showers continued to pepper the Midwest, with daily-record totals for August 16 being set in New Philadelphia, OH (2.51 inches), and Rapid City, SD (1.14 inches). Muskegon, MI, measured a daily-record sum (3.35 inches) for August 18. In West Virginia, Charleston (4.23 inches on August 16) experienced its wettest August day and second-wettest day during any month, behind only 5.60 inches on July 19, 1961. Columbus, OH, secured its second-wettest August, with the month-to-date total of 9.91 inches ranking behind only 11.46 inches in 2003. As the week progressed, heavy showers moved into other areas, including the central Plains and the East. Pueblo, CO, posted a record-setting total (1.60 inches) for August 17. Three days later, daily-record amounts for August 20 reached 3.27 inches in Islip, NY; 2.87 inches in Columbus, OH; and 2.35 inches in both Paducah, KY; and Wheeling, WV. With 5.31 inches on the 21st, Wilmington, NC, experienced its wettest day since August 7, 2024, when 5.66 inches fell. Late-summer warmth lingered across northern and eastern Alaska, where weekly temperatures averaged as much as 5°F above normal. On the 16th, the daily-record high of 75°F in Kotzebue marked the warmest August day in that location since August 4, 2021, when it was 80°F. Despite the warmth, precipitation was widespread, even in areas of southeastern Alaska that had been trending very dry. Yakutat measured weekly rainfall totaling 3.59 inches, boosting the August 1-22 sum to 3.64 inches (40 percent of normal). Farther south, Tropical Storm Moke threatened Hawaii, about a week after Hurricane Lala dumped at least 24 to 36 inches of rain on parts of the Big Island and caused extensive flooding and debris flows. Early Sunday, August 23, Moke made its closest pass to the Big Island, about 300 miles south of Hilo. Prior to Moke’s approach, weather conditions on the Big Island had favored hurricane recovery efforts. Still, Hilo’s month-to-date rainfall through the 22nd totaled 17.62 inches (217 percent of normal), with 14.18 inches occurring from August 14-16.

23-29: Remnant moisture associated with former Tropical Storm Iselle was drawn into the North American monsoon circulation, contributing to a late-week increase in Western shower activity. Sudden and deadly flooding developed Saturday in Grand Canyon National Park’s Bright Angel Canyon, despite Iselle having been a short-lived storm that remained 0well off the Mexican Pacific Coast during its August 23-26 life cycle. 

Early in the week, thunderstorms were scattered across areas from the Plains eastward. Record-setting rainfall totals for August 23 topped the 2-inch mark in Bridgeport, CT (2.36 inches); Brooksville, FL (2.15 inches); and Broken Bow, NE (2.14 niches). Bridgeport also secured its wettest summer on record, with a June-August total of 21.24 inches, or 192 percent of normal (previously, 20.23 inches in 1972). Watertown, NY, collected a daily-record sum of 2.16 inches on August 24. Spotty relief from heat and dryness occurred across the Plains and South, with daily-record totals being set in locations such as Amarillo, TX (1.78 inches on August 25), and McComb, MS (2.46 inches on August 27). For Amarillo, the rain on the 25th accounted for more than 80 percent of the monthly total of 2.13 inches. For McComb, the rain on the 27th accounted for more than two-thirds of the August sum of 3.46 inches. Farther west, a few showers developed across California—0.01 inch fell in Santa Barbara and Paso Robles on August 27, and in Stockton and Modesto on August 28—but meaningful late-week Western totals were mostly limited to the Four Corners States. Much of Alaska ended the month on a stormy note, capping a wet August. In fact, August 27 featured daily-record rainfall totals in Bethel (1.49 inches) and Nome (0.91 inch). Bethel ended the month with rainfall totaling 5.36 inches, 160 percent of normal. Other August totals included 4.57 inches (169 percent of normal) in Bettles; 4.68 inches (161 percent) in McGrath; and 6.31 inches (196 percent) in Nome. In contrast, August rainfall was less than one-half of normal in Yakutat (5.78 inches, or 42 percent of normal) and Ketchikan (4.15 inches, or 37 percent). Farther south, Hawaii’s active August ended on a mostly quiet note. Still, due to earlier downpours, Hilo—on the Big Island—noted August rainfall totaling 20.85 inches (185 percent of normal). Rainfall was less impressive in leeward locations, with Honolulu, Oahu, measuring an August sum of 0.91 inch (108 percent of normal).

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