NATIONAL STORM SUMMARY

AUGUST 2024

July 28-Aug. 3: Elsewhere, a Western break from extreme heat was short-lived, with record-setting high temperatures returning during the second half of the week. However, the fleeting cool spell allowed firefighters to work on containment efforts for some of the largest Western wildfires, including the 402,000 acre Park Fire near Chico, CA, which has destroyed more than 600 structures. Near- or above-normal temperatures covered much of the country, although weekly readings were close to normal levels in much of California, the Great Basin, and the Intermountain West, along with the western Gulf Coast region and the Southeast.  With a burned acreage of more than 400,000 acres, the Park Fire near Chico, CA, became the fourth-largest wildfire in modern California history, behind only the 1.03 million-acre August Complex (2020), the 963,000-acre Dixie Fire (2021), and the 459,000-acre Mendocino Complex (2018). The Park Fire was also responsible for the destruction of more than 600 structures.

Monsoon related showers dotted the West, including a few spots in southern California, where record-setting totals for August 2 included 0.58 inch at Big Bear Lake and 0.32 inch in Campo. Earlier, a few showers associated with a cold front had swept across the Northwest, with Hoquiam (0.65 inch) and Olympia (0.20 inch) netting daily record amounts for July 29. Meanwhile, heavy showers and locally severe thunderstorms frequently swept across the Midwest, often tracking from northwest to southeast. Some of late July’s most concentrated streaks of wind and hail damage stretched from the upper Midwest into the Ohio Valley. On July 31 in Nebraska, thunderstorm-driven wind gusts were clocked to 90 mph in Omaha and 83 mph in Lincoln. Meanwhile, Des Moines, IA, received 5.16 inches of rain during the last 4 days of the month, including a daily record sum of 3.55 inches on July 31. Other Midwestern daily record totals included 2.04 inches (on July 29) in Gaylord, MI, and 1.26 inches (on July 31) in Minneapolis-St. Paul, MN. Farther east, torrential rainfall in parts of Vermont resulted in significant flash flooding. St. Johnsbury, VT, received 8.04 inches of rain on July 29-30, including 5.90 inches on the latter date. A nearby, long-term climate site in St. Johnsbury measured 8.08 inches in a 24-hour period on July 29-30, breaking the 24-hour station record of 4.99 inches, set on July 27-28, 1913. In early August, heavy showers continued to pepper the Midwest and East. Rainfall records for August 1 included 2.30 inches in Harrisburg, PA; 1.91 inches in Green Bay, WI; and 1.82 inches in Knoxville, TN. With 3.45 inches, Danville, VA, tallied a record-setting total for August 2. Eastern daily-record amounts for August 3 reached 2.96 inches in Asheville, NC, and 1.72 inches in Concord, NH.

4-10: Hurricane Debby made landfall around daybreak on August 5 in Florida’s Big Bend; drifted across northern Florida and eastern Georgia before moving offshore; and made a final landfall (as a tropical storm) on August 8 northeast of Charleston, SC. Thereafter, the former hurricane accelerated northward, but still managed to trigger flash flooding as far north as New York. Farther south, rainfall totals of 8 to 16 inches or more resulted in extensive lowland flooding near Tampa Bay and from northeastern Florida into the eastern Carolinas Farther west, notable rainfall was mostly limited to portions of the Rockies, Plains, and Southwest, as the monsoon circulation interacted with a pair of cold fronts. There was also a streak of rain from the northern Plains into the Great Lakes region, while dry weather prevailed throughout the week in the lower and middle Mississippi Valley and neighboring regions.

 

In advance of Hurricane Debby’s landfall, torrential rain erupted across west-central Florida. With 11.06 inches (and a peak wind gust to 64 mph) on August 4, Sarasota-Bradenton, FL, experienced its wettest day on record (previously, 10.80 inches on June 23, 1945). Other daily record totals on the 4th in the Tampa Bay area included 6.19 inches in Ruskin and 4.85 inches in Tampa. Ruskin’s 2-day (August 4-5) sum climbed to 10.26 inches. On the 5th, the day of Debby’s landfall, daily record amounts included 5.41 inches in Gainesville, FL; 4.71 inches in Charleston, SC; 4.46 inches in Jacksonville, FL; and 4.32 inches in Alma, GA. Peak gusts topped 50 mph on August 5 in numerous locations, including Jacksonville, FL (58 mph); Valdosta, GA (57 mph); Savannah, GA (55 mph); Charleston, SC (51 mph). On August 6, daily-record totals topped the 3-inch mark in North Myrtle Beach, SC (3.99 inches); Savannah, GA (3.21 inches); and Columbia, SC (3.14 inches). Separately, heavy rain and severe thunderstorms raced across the northern Corn Belt and the mid-Atlantic. Northern Ohio was hit particularly hard by high winds and power outages; peak gusts on August 6 included 70 mph in Cleveland and 58 mph in Youngstown. Cleveland’s Burke Lakefront Airport recorded 79 mph. In New Jersey, heavy rain sparked flash flooding, with Trenton netting a daily-record sum (4.45 inches) for August 6. As Tropical Storm Debby lurked offshore, daily-record totals for August 7 included 5.66 inches in Wilmington, NC; 3.11 inches in Fayetteville, NC; and 2.98 inches in North Myrtle Beach, SC. Martinsburg, WV, measured daily-record totals (2.43 and 3.41 inches, respectively) on August 7-8. On the 8th, the day of Debby’s final landfall, daily-record amounts in North Carolina reached 4.02 inches in Raleigh-Durham and 3.91 inches in Greensboro. As rain shifted into the Northeast on August 9, record-setting amounts included 3.30 inches in Williamsport, PA, and 3.24 inches in Massena, NY. In the wake of the Southeastern deluge, top-three crests occurred on the Ogeechee River near Eden, GA, and the Edisto River near Givhans Ferry, SC. The water level in Eden peaked at 6.97 feet above flood stage on August 10, highest since 1929. The August 11 crest in Givhans Ferry, 7.21 feet above flood stage, was the highest since September 21, 1945. At week’s end, heavy showers were scattered across the southern Plains, with daily-record totals being set in Texas locations such as Dalhart (1.88 inches on August 9) and Lubbock (1.32 inches on August 8). Dalhart set another daily record, with 1.41 inches, on August 10.

11-17: Midwestern rain, mainly during the second half of the week, provided much-needed moisture for filling summer crops. The Corn Belt, parts of which had been trending dry in recent weeks, also benefited from another week of mild weather, with temperatures remaining well below stressful levels for corn and soybeans. Locally heavy showers extended to other regions, including the Plains, East, and Southwest.

At week’s end, showers associated with a cold front overspread the Pacific Northwest, boosting topsoil moisture and aiding wildfire containment efforts. Still, more than 50 active Western wildfires were in various stages of containment, with those fires accounting for 2.2 of 5.4 million year to-date burned acres across the country.

As the week began, downpours dotted the central Plains and neighboring areas. Oklahoma City, OK, experienced its wettest August day on record, with a 6.59-inch sum on the 11th; previously, the record had been 5.06 inches on August 14, 2018. Elsewhere in Oklahoma, August 11-12 rainfall totals included 6.60 inches in Muskogee; 4.41 inches in Jenks, south of Tulsa; and 3.53 inches in McAlester. Isolated downpours also occurred across Florida’s peninsula, where Sarasota-Bradenton netted a daily-record sum (3.00 inches) for August 11. A few days later, monsoon-related showers were generally heaviest in Utah, where 72-hour totals (from August 11-14) at the Hans Flat Ranger Station in The Maze section of Canyonlands National Park reached 2.82 inches. By the middle of the week, thunderstorms overspread portions of the Plains and Midwest, with daily-record totals for August 14 being set in Aberdeen, SD (2.87 inches), and West Plains, MO (2.44 inches). West Plains went on to measure another daily record (2.47 inches) on August 16, lifting the weekly sum to 6.54 inches. Meanwhile, daily-record amounts across the North included 1.65 inches (on August 15) in Grand Forks, ND, and 2.10 inches (on August 16) in Marquette, MI. Elsewhere on the 16th, London, KY, also netted a daily-record sum (1.82 inches). Outside the contiguous U.S., Tropical Storm Ernesto passed over the U.S. Virgin Islands (USVI) late August 13 while packing sustained winds near 65 mph. That evening, wind gusts were clocked to 70 mph at King Airport on St. Thomas and 65 mph at Rohlsen Airport on St. Croix. In neighboring Puerto Rico, a gust to 74 mph was recorded early on the 14th at former Roosevelt Roads Naval Station. Storm-total rainfall broadly reached 4 to 8 inches or more across both Puerto Rico and the USVI, while some storm-surge flooding was reported on south facing shores, especially in the latter territory. At week’s end, precipitation overspread the Pacific Northwest. Record-setting rainfall totals for August 17 included 0.58 inch in Olympia, WA, and 0.50 inch in Hillsboro, OR.

18-24: Locally heavy rain also fell in Florida, the Northeast, and the Pacific Northwest. Much of the Northeastern rain fell early in the week, leading to flash flooding in southwestern Connecticut. Soon the focus for heavy showers shifted to the northern Plains. The Northern rain was enhanced by the interaction between cold fronts and the Southwestern monsoon circulation. With seasonal changes taking place, precipitation frequency and intensity increased in the Northwest, extending as far south as northern California.

the week began, a deluge from New York City into Connecticut led to flash flooding. New York’s LaGuardia Airport netted a daily-record total (2.96 inches) on August 18, while several 9- to 12-inch totals were observed from central Long Island, NY, into southwestern Connecticut. An unofficial observation site near Newtown, CT, received 12.17 inches in a 24-hour period on August 18-19. Another round of rain on August 19 led to daily-record totals in New York locations such as Albany (1.89 inches) and Watertown (1.03 inches). Meanwhile, scattered showers swept from the Pacific Northwest to the northern Plains. By August 20, record-setting rainfall totals in South Dakota included 2.09 inches in Pierre and 1.37 inches in Huron. Heavy showers also dotted Florida, where daily-record totals included 2.13 inches (on August 21) in Punta Gorda; 1.96 inches (on August 22) in West Palm Beach; and 2.99 inches (on August 24) in Miami. Concurrently, August 23 rainfall in northwestern California resulted in daily-record totals of 2.05 inches in Crescent City and 1.19 inches in Eureka. On August 24, daily record totals also topped an inch in Bellingham, WA (1.19 inches), and Blue Canyon, CA (1.06 inches). Rare August rain fell as far south as central California, where record-setting totals for August 24 reached 0.10 in San Francisco (SFO Airport) and 0.05 inch in Stockton.

Early Sunday, August 25, Hurricane Hone—with sustained winds near 85 mph—passed about 40 miles south of South Point on the Big Island of Hawaii. Impacts on the Big Island, where Hilo netted 6.31 inches of rain on August 24-25, included tropical showers, gusty winds, and pounding surf. August 25 peak wind gusts indirectly associated with Hone were clocked to 47 mph in Kahului, Maui, and 43 mph in Honolulu, Oahu. A gust to 72 mph was reported late on the 24th on the Big Island at Kohala Ranch. Meanwhile, 48-hour rainfall totals ending at 6 am HST on August 26 ranged from 10 to 20 inches or more at several Big Island locations, with Hakalau reporting 28.82 inches and Mountain View receiving 21.30 inches.

25-31: Midwestern rain provided beneficial moisture for immature corn and soybeans, although heavier showers bypassed drier sections of the eastern Corn Belt. Some of the most substantial rain, 1 to 3 inches or more, fell in the upper Mississippi Valley. Meanwhile, drought-stricken areas of the central Appalachians also received much-needed rain, although totals were mostly under 2 inches. Farther south, disorganized tropical moisture contributed to locally heavy showers, especially in the central Gulf Coast region and along the upper Texas coast. Heavy showers also dotted Florida’s peninsula.

Early in the week, heavy showers were scarce, although Jacksonville Executive at Craig Airport, FL, netted a daily-record sum of 3.23 inches on August 25. A day later, Northwestern record-setting totals for August 26 included 0.93 inch in Miles City, MT, and 0.60 inch in Bellingham, WA. By August 27, thunderstorms sweeping through the Midwest resulted in gusts to 66 mph in Toledo, OH, and 65 mph in Lansing, MI, while South Bend, IN, collected a daily record sum of 1.19 inches. Two days later, another round of Midwestern storms contributed to record-setting amounts for the 29th in Wisconsin locations such as La Crosse (2.02 inches) and Eau Claire (1.49 inches). Late-month thunderstorms also pelted parts of the mid-Atlantic and central Appalachians, resulting in daily-record amounts in Parkersburg, WV (3.58 inches on August 31), and Virginia’s Dulles International Airport (1.92 inches). Prior to the late-month rain, Parkersburg had received rainfall totaling just 0.07 inch from August 4-27. Spotty showers also developed near the Gulf Coast, where Lafayette, LA, measured 1.15 inches on August 31, a record for the date.

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