Unseasonable Tropical Storm Rachel Delivers Extreme Rain and Flood Risks to Arizona

2026-10-11 general

Phoenix, Sunday, 11 October 2026.
Fueled by record-warm Pacific waters, Tropical Storm Rachel is driving rare October torrential rains, high winds, and flash flooding risks across Arizona and the Desert Southwest.

Storm Landfall and Current Status

Tropical Storm Rachel is expected to make landfall early Sunday, Oct. 11, 2026, bringing moderate to heavy rainfall and gusty winds to Arizona through Tuesday, Oct. 13, 2026 [1]. The storm is racing northeast and headed for landfall over northern Baja California on Saturday night, impacting the Southwest region [4]. Unseasonable tropical moisture is pushing into Arizona, bringing widespread rainfall and cooler temperatures across the region [1]. Local authorities and weather services have issued First Alert Days as heavy rain threatens regional transport networks and outdoor infrastructure operations throughout the Southwest [1].

Storm Landfall and Current Status

A flood watch is active from 11 a.m. Oct. 10, 2026, through 5 a.m. Oct. 12, 2026, for Mojave, Yavapai, western Coconino, northern Gila, and far southern Navajo counties due to potential excessive runoff [1]. Metro Phoenix rainfall estimates range from 6.35 mm to 38.1 mm (0.25 to 1.50 inches), while Mohave County remains under a flood alert from 5 a.m. Oct. 11 to 5 a.m. Oct. 12 [1]. Additionally, 1 to 3 inches of rain is possible across portions of the interior Southwest over the next 48 hours, with isolated rainfall totals over 3 inches possible in mountainous areas [4].

Regional Weather Alerts and Timelines

Wind advisories for Oct. 11, 2026, cover most of the state with sustained winds up to 56 km/h (35 mph) and gusts reaching 89 km/h (55 mph) [1]. The difference between peak gusts and sustained winds is significant, calculated as 33 km/h [1]. Wind Advisories are in effect on Sunday across most of the state, with sustained winds could reach 35 mph with peak gusts between 40 and 50 mph [2]. The Storm Prediction Center identified a marginal risk for severe storms across central, southern, and western Arizona, noting that while gusty winds are the primary threat, an isolated tornado cannot be ruled out [1].

Regional Weather Alerts and Timelines

Scattered showers and storms are expected to persist through Oct. 13, 2026, with a brief lull Sunday night into Monday [1]. High temperatures are forecasted to drop from the lower 90s on Oct. 10 to upper 70s by Oct. 13–14, 2026 [1]. Highs will reach 103 this afternoon, with clouds increasing tonight, before dropping significantly over the next few days to the 70s by Tuesday and Wednesday [3]. Rain chances will remain around 30% Monday (Columbus Day), followed by only a slight chance of showers Tuesday morning [3].

Economic and Infrastructure Implications

Heavy rain threatens regional transport networks, local supply chains, and outdoor infrastructure operations throughout the Southwest [1]. Specific road closures are anticipated at Midway area’s Frontage Road and Pacific Coast Highway as part of flood mitigation efforts [6]. Orange County beaches in Southern California were preparing for the impacts through the distribution of sandbags and even the brief closure of entire beaches [4]. The City of Newport Beach on Saturday declared a local emergency in response to coastal flooding, saying all piers were closed until further notice [4].

Economic and Infrastructure Implications

SDG&E is actively monitoring conditions and positioning personnel and equipment in response to Tropical Storm Rachel [6]. Kevin Geraghty, Chief Operating and Safety Officer of SDG&E, stated teams are preparing for changing weather conditions and are ready to respond if impacts occur [6]. Downed power lines should be reported to 911 and SDG&E at 1-800-411-7343 [6]. Residents are instructed to prepare by clearing debris from storm drains and securing trash or recycling bin lids to mitigate infrastructure damage [6].

Historical Context and Climate Factors

San Diego, California, is under a tropical storm watch, marking only the second time this has occurred in its history, following Hurricane Hilary in 2023 [1]. Ocean temperatures are 5.5 °C to 7.2 °C (10 to 13 °F) higher than normal due to El Niño and a marine heat wave, allowing the storm to maintain strength in typically cooler waters [7]. California coastal water levels are currently elevated due to a near-record strong super El Niño event, exacerbating the risk of coastal flooding from Rachel’s storm surge and waves [5]. The National Oceanic and Atmospheric Administration’s Climate Prediction Center announced on 2026-10-08 that there is a nearly 100% probability of a very strong El Niño season [7].

Historical Context and Climate Factors

Historical data includes El Cordonazo in September 1939, which caused 93 total deaths and dumped 142.7 mm (5.62 inches) of rain on Los Angeles [7]. Hurricane Nora in September 1997 caused street flooding in Imperial County, Coachella Valley, and San Diego, plus damage to 48 homes in Seal Beach [7]. Rainfall totals in San Diego and Las Vegas are projected at 25.4 mm (1 inch) or more, representing double the typical October rainfall for San Diego and triple for Las Vegas [5]. This unusual event is being made possible by both coincidence of this early arriving low-pressure trough off the coast of California and the record warm ocean temperatures [7].

Public Safety and Preparation

Residents can obtain up to 10 empty sandbags at 11 designated recreation centers with proof of residency, or report storm issues via the Get It Done app or 619-527-7500 [6]. San Diego residents are advised to report storm-related issues such as flooding or downed trees via the Get It Done app or by calling 619-527-7500 [6]. Flash flooding will be possible in creeks, normally dry washes, swimming holes, and over recently burned areas [2]. Low-water crossings may be flooded, so drivers should not attempt to drive through them [2].

Public Safety and Preparation

Tropical Storm Rachel will bring hazardous conditions to Baja California and the Southwest this weekend, including damaging winds, flash flooding, and life-threatening surf and rip currents [8]. Life-threatening surf and rip current conditions are expected due to the storm’s impact [5]. Major coastal flooding has already been occurring in some areas, with observed water levels running as much as 1.5 feet above predictions [5]. Life-threatening emergencies must be reported to 911 [6].

Sources

Tropical Storm Rachel Arizona Weather