Flood — Monterey, California

2024-03-30 · near Notleys Lndg, Monterey, California

$10

Property damage

Event narrative

A landslide along California Highway 1 near the Rocky Creek Bridge on March 30 forced the closure of the road at Palo Colorado. The landslide took out parts of the southbound lane of Highway 1 with the northbound lane also in danger. Combined with earlier closures of Highway 1 at Limekiln State Park near Lucia and the Nacimiento-Ferguson Road due to the Dolan Fire, the closure left the area around Big Sur isolated from the outside world. As of March 31, vehicles are only allowed to travel to the north in corridors at 8 AM and 4 PM daily.

The event followed a very active 48 hours of weather with heavy rain, strong winds and a rare severe thunderstorm warning. MRMS rainfall rates were as high as 1.9/hour on the 29th and a nearby gauge recorded 3.9 in 48 hours. Winds were also strong, with radar velocity data suggesting up to 60 mph gusts and nearby observations as high as 48 mph. A gale warning was issued for the coastal zone at 235AM on Thursday, March 28th. Valid 9AM-9PM Friday, easily verified by radar data, but no in situ observations are available. A wind advisory was issued at 205AM Thursday, March 28th and upgraded to a high wind warning at 215AM on Friday, March 29th. The high wind warning was valid 1AM-9PM Friday, and verified by a 62 mph gusts recorded at Lime Creek Road (741 ft). 5 separate Special Marine Warnings were issued for the affected coastline on Friday for winds greater than 40 kts and possible waterspouts. The issue times were 1226PM, 143PM, 243PM, 430PM, and 457PM. Again, these were only verified with radar data due to limited in-situ measurements over the water. A Severe Thunderstorm Warning was issued at 312PM Friday for 60 mph wind gusts and a possible tornado based on radar indicated rotation. There were no reports of a tornado, and the highest observed wind gusts at the time of the warning were 46 mph, although a 62 mph gust was recorded at 540PM, after the warning expired (see high wind warning above). A Flood Advisory was issued at 448PM Friday that covered the slide area for urban and small stream flooding. While most of the severe weather in this area occurred on Friday, there were 2 Special Weather Statements issued at 221AM and 402AM for 30-40 mph wind and pea sized hail just south of the slide. The first was verified with a 31mph gust at 250AM from Pfeiffer Ridge Road.

Wider weather episode

A deepening low with an associated mature cyclone came to California on March 29, with widespread rain associated with the system. Continuing instability the next day resulted in noticeable thunderstorms with hail reported in several places across the Bay Area, including Walnut Creek, Belmont, and south of San Jose. In Monterey County, significant rainfall contributed to a landslide that forced the closure of California Highway 1 north of Big Sur.

View location on OpenStreetMap → (36.3791, -121.9031)

Source: NOAA Storm Events Database, event_id 1161089. Narrative written by the NWS forecast office that issued the report.