Hurricane Kay (2022)

From September 4 to 9, Hurricane Kay's expansive rainbands brought rainfall to a cumulative 16 states across Mexico. Precipitation progressed from southern states, such as Oaxaca and Guerrero, to Baja California in the northwest portion of the nation. Maximum daily rainfall totals in Guerrero and Jalisco reached 140 and 135.4 mm (5.51 and 5.33 in), respectively, on September 4. Rainfall was most significant across the Baja California Peninsula, with three-day totals reaching 383 mm (15.1 in) in Guadeloupe and 370 mm (14.6 in) in Sierra de San Francisco. The majority of these totals fell within 24-hour spans. The storm struck Socorro Island on September 6, bringing 154 mm (6.1 in) of rain that day.[16] In addition to flooding, landslides, and falling trees, the hurricane was also responsible for three deaths in Guerrero.[17] Kay also damaged most of the Baja California peninsula with strong winds and heavy rain, which caused much flooding and mudslides, though there were no reports of injuries. Shortly before the storm hit, over 1,600 people evacuated to shelters according to Baja California Sur state officials.[18] Road and agricultural damage in Baja California Sur exceeded 72 million pesos (US$3.6 million), though again, no injuries were reported.[19][20]

Moisture associated with Hurricane Kay brought widespread heavy rain, flash floods, and damaging winds to the Southwestern United States.[21] The National Centers for Environmental Information tabulated $7.02 million in damage across four states in relation to the storm with the majority incurred by California. A mudflow in Southern California claimed the life of one person.[22][23][24][25]

Flash floods in Death Valley National Park washed out portions of Highway CA-190

Abundant moisture associated with the remnants of Kay led to scattered showers and thunderstorms in the Southwestern United States, particularly in California. Rainfall totals varied across the regions, with Mt. Laguna recording the highest rainfall amount of around 5 in (130 mm). In Imperial County, California, falling boulders created traffic along an area of I-8. Los Angeles set records for both a daily rainfall of 0.2 in (5.1 mm) as well as a daily heat record of 102 °F (39 °C) as Kay moved through on September 9.[21] Localized flooding in Death Valley National Park covered several roads, including a 6 mi (9.7 km) stretch of road in Badwater Basin. A section of Route 190 was washed out near Towne Pass. A bus became stuck in softened sand near this location, briefly stranding motorists.[26] A Major League Baseball game between the San Diego Padres and the Los Angeles Dodgers was delayed due to the rain.[27] The rainfall was beneficial to crews in Riverside County, California, battling the Fairview Fire, as it mitigated some of the threat posed by the high winds and dry conditions. This mitigated the risk to an estimated 18,000 homes.[21]

On September 12, mudflows affected several communities in the San Bernardino Mountains. A total of 2.4 in (61 mm) of rain fell within an hour over burn scars from the Apple and El Dorado fires. A series of flows impacted multiple valleys in Forest Falls, resulting in a cascade of water, mud, and debris. Initial evacuation orders were rescinded as travel became impossible. One person was killed when her home was crushed by debris.[28] A team of 120 personnel from various rescue departments were dispatched to search through mud piled 6 ft (1.8 m) deep for the killed person for several days. Heavy machinery and cadaver dogs were used throughout the search.[29] A total of six homes were destroyed in Forest Falls, two in Oak Glen, 22 other homes were otherwise damaged, and one business was severely damaged. Approximately 3,000 people were affected in the region.[30][31]

Powerful winds accompanied the storm's rainfall, particularly in San Diego County, reaching a maximum of 109 mph (175 km/h) at Cuyamaca Peak. Power outages affected tens of thousands across the Los Angeles Metro, though these generally lasted only a few hours.[21] Gale and surf warnings covered the southwestern counties of California, with officials in Long Beach providing sandbags to residents. Temporary berms were constructed in Alamitos Beach to protect coastal homes.[21] Severe beach erosion occurred in Southern California, with some coasts in the Los Angeles area losing 5 ft (1.5 m) of sand vertically.[32]

On September 16, California Governor Gavin Newsom declared a state of emergency for Imperial, Inyo, Los Angeles, Riverside, and San Bernardino counties owing to damage caused by Kay.[33]

Described as an "unusual setup" for Utah in particular, the National Weather Service issued slight and moderate flood-risk outlooks alongside flash flood watches for the aforementioned state along with Arizona, Nevada, and New Mexico. This rain followed deadly floods in the region just a month prior during one of the wettest monsoon seasons on record.[34] In Nevada, wind gusts associated with storms reached 62 mph (100 km/h) near Gold Hill.[35] Heavy rain across the Mojave Desert caused scattered flash floods. In Overton, Nevada, 1.89 in (48 mm) of rain fell, including 0.8 in (20 mm) in 20 minutes. This inundated roads in several parks and left vehicles stranded across Valley of Fire State Park.[36] Flood-related damage across the state was tabulated at $167,000.[24] Extensive flooding occurred in Mohave County, Arizona, along the border with Nevada, forcing the closure of multiple roads. In just under two hours, 3.86 in (98 mm) of rain fell in Getz which triggered flash floods. This inundated up to ten homes and necessitated eight water rescues in the community.[37] Another swift water rescue was performed along Oatman Highway.[38] Damage in Arizona reached $139,500.[23] In New Mexico, north-to-south propagating thunderstorms brought heavy rain and strong winds to the northern mountains. A peak gust of 67 mph (108 km/h) was observed near Stanley.[39] A nearly stationary thunderstorm produced over 2 in (51 mm) of rain over areas recently burned by the Calf Canyon fire in El Porvenir. The Beaver and Gallinas creeks flooded along Highway 65, leaving behind debris on the roads and inundating nearby homes.[40] Another storm similarly affected areas within the McBride Fire burn scar in Lincoln County.[41] Damage across New Mexico reached $220,000.[25]