Sadly this week we've seen some examples of how this record-setting El Niño+Blob fueled weather is already impacting the southwestern United States, giving us some idea of how parts of the rest of the 2015 Pacific Hurricane Season, and indeed, likely a very tropically-connected winter and spring, could play out.
"I've lived here all my life, never seen anything like it... By the time we had the National Weather Service on the phone, it had already happened."
At least 16 deaths have now been confirmed in a flash flood tragedy this week near the Utah-Arizona border, including Zion National Park, in storms that were fueled by significant remnant moisture of former Hurricane Linda. (Still-updating story on KLS.com)
Additionally, today, September 15, 2015, the remnants of Category 3 Hurricane Linda conspired with an upper-level low off the California coast to deliver the most rain for any day in the month of September in Los Angeles since the September 1939 El Cordonazo~Lash of St. Francis Long Beach Tropical Storm, also making it the "second wettest September day on record at the downtown observation station where records date back to 1877," according to Weather.com
Past is prologue, and history does have a few examples of how El Niños can impact this part of the country, a part that is far more accustomed to seeing an Excessive Heat Warning, than warnings related to moisture or remnant circulations of tropical cyclones.
Here are a few of the more significant historical examples, sourced from Wikipedia:
October 2, 1858: The 1858 San Diego hurricane was a very rare California hurricane. It is the only known tropical cyclone to impact California as a hurricane, although other systems impacted California as tropical storms. The storm caused damage to many homes and other constructions in San Diego. San Pedro experienced heavy rainfall, El Monte experienced high winds that damaged its corn crops and trees, and Los Angeles and Visalia experienced large amounts of rain but low wind. A later estimate stated that if a similar storm happened in 2004, it would have caused $500 million in damage.
September 4–7, 1939: The remnants of a hurricane brought over a year's worth of rain to parts of southern California
September 25, 1939: The 1939 California tropical storm, also called the 1939 Long Beach tropical storm, El Cordonazo, The Lash of St. Francis was a tropical cyclone that hit Southern California in September, 1939. Formerly a hurricane, it was the only tropical storm to make landfall in California in the twentieth century... The flooding killed 45 in Southern California, although some of these may be attributable to the rain immediately before the tropical storm. At sea, 48 were killed. The National Hurricane Center only attributes 45 deaths to this system. Six people caught on beaches drowned during the storm. Most other deaths were at sea. Twenty-four died aboard a vessel called the Spray as it attempted to dock at Point Mugu. The two survivors, a man and a woman, swam ashore and then walked five miles (8 km) to Oxnard. Fifteen people from Ventura drowned aboard a fishing boat called the Lur. Many other vessels were sunk, capsized, or blown ashore. Many low-lying areas were flooded. The Hamilton Bowl overflowed, flooding the Signal Hill area. Along the shore from Malibu to Huntington Beach houses were flooded. Throughout the area, thousands of people were stranded in their homes. Streets in Los Angeles proper were covered with water, flooding buildings and stalling cars. Flooding in Inglewood and Los Angeles reached a depth of 2 to 3 feet. Construction on a flood control project in the Los Angeles River's channel by the Army Corps of Engineers was stopped by the flooding. In Long Beach windows throughout that city were smashed by the wind. At Belmont Shore, waves undermined ten homes before washing them away. Debris was scattered throughout the coast. Agriculture was disrupted. Crop damage in the Coachella Valley reached 75%.
September 1970: Tropical Storm Norma was the fourteenth named tropical cyclone of the 1970 Pacific hurricane season. The storm formed off the coast of Mexico and intensified rapidly, peaking as a strong tropical storm on September 3 before starting a weakening trend which saw it dissipate before making landfall on Baja California. While the storm never made landfall, the remnants from the storm fueled the Labor Day Storm of 1970, which caused floods in Arizona that resulted in heavy damage and loss of life. The rainfall from this storm broke records, mostly for 24-hour rainfall totals. Despite not being tropical when the damages were done, Norma is considered to be the deadliest system in Arizona history.
September 10–11, 1976: Hurricane Kathleen was a tropical cyclone that caused destructive impacts in California. On September 7, 1976, a tropical depression formed; two days later it accelerated north towards the Baja California Peninsula. Kathleen brushed the Pacific coast of the peninsula as a hurricane on September 9 and made landfall as a fast-moving tropical storm the next day. With its circulation intact and still a tropical storm, Kathleen headed north into the United States and affected California and Arizona. Kathleen finally dissipated late on September 11... Damage in the United States was considerable. California received record rainfall, with over a foot of rain falling in some areas. Flooding caused catastrophic destruction to Ocotillo, and six people drowned. Flooding extended west; railway tracks were destroyed in Palm Desert and high winds and severe flooding were recorded in Arizona. Overall, the damage total was $160 million (1976 USD) and 12 deaths were attributed to the storm.
October 1983: Tropical Storm Octave was considered the worst tropical cyclone in the history of Arizona... In Arizona, the highest rainfall total was 12.0 in (300 mm) at Mount Graham. In Tucson, flood waters were reportedly 8 ft (2.4 m) high. Throughout the state, excessive rainfall caused many rivers to overflow. After the rain ended, the Santa Cruz, Rillito, and Gila rivers experienced their highest crests on record. Five towns – Clifton, Duncan, Winkelman, Hayden, and Marana – were almost completely flooded. In Marana, many homes were submerged, forcing residents to be evacuated. Over 700 homes were destroyed in Clifton. In addition, 86 of the town's 126 business were heavily damaged due to the flooding. Around 3,000 buildings were destroyed due to Octave. A total of 853 houses, mobile homes, and apartments were destroyed while 2,052 others were damaged. About 10,000 people were temporarily left homeless. Damage in Arizona totaled $500 million (1983 USD), which was above the preliminary estimate of $300 million. Fourteen people drowned and 975 persons were injured. Elsewhere, Octave was responsible for $12.5 million in damage in New Mexico.
September 25–26, 1997: Hurricane Nora was only the third tropical cyclone on record to reach Arizona as a tropical storm. Nora was the fourteenth named tropical cyclone and seventh hurricane of the 1997 Pacific hurricane season. The September storm formed off the Pacific coast of Mexico, and aided by waters warmed by El Niño, eventually peaked at Category 4... In the United States, there were no direct deaths blamed on the hurricane. However, the California Highway Patrol attributed three or four traffic fatalities in southern California to the weather. Damage totals in the United States are not fully known, although media summaries of Nora included a loss to agriculture preliminarily estimated at several hundred million dollars, and at least one study places the figure at $150–200 million (1997 USD). It is estimated that $30–40 million (1997 USD) in damage to lemon trees occurred. Although Nora was significantly weakened, near hurricane-force winds were observed at the Dixie National Forest in southwestern Utah, where strong gusts sheared off the tops of large trees.