Arroyo Grande

Every recorded tornado

1. Injuries and deaths are for the tornado’s whole path, which may extend beyond this area.
2. Weak tornadoes were under-recorded before Doppler radar coverage became national in the early 1990s, so earlier decades read low. Ratings use the Fujita scale before February 2007 and the Enhanced Fujita scale after.

Storm Prediction Center severe weather database, 1950 to 2025.

Every large fire

1. Large fires mapped by the Monitoring Trends in Burn Severity program since 1984: 1,000 acres or more in the West, 500 or more in the East. Prescribed burns are excluded. Acres here are the part of each perimeter inside this place.

Monitoring Trends in Burn Severity (USGS and U.S. Forest Service), 1984 to 2026.

Smoke overhead

1. A smoke day is a date on which a smoke plume traced by NOAA Hazard Mapping System analysts from satellite imagery covered this place's point (the county's population centre or the city centre). Counts here are of medium or heavy smoke. Since 2018 analysts have often drawn light smoke as one area over most of the continent, so light-smoke counts are not comparable from year to year. The plumes show smoke anywhere in the air above, not air quality at the ground, and smoke hidden by cloud is missed.

NOAA Hazard Mapping System smoke analysis, 2011 to 2026, retrieved October 30, 2026.

Flood insurance figures are for San Luis Obispo County, the county that contains Arroyo Grande.

Claims by ZIP code

This product uses the Federal Emergency Management Agency's OpenFEMA API, but is not endorsed by FEMA. The Federal Government or FEMA cannot vouch for the data or analyses derived from these data after the data have been retrieved from the Agency's website(s).

OpenFEMA NFIP Redacted Claims v3, refreshed August 4, 2026. NOAA Storm Events through 2026.

River crests

River gauges in San Luis Obispo County, the county that contains Arroyo Grande.

River gauges

1. Crests are the highest and the recent crests the National Weather Service lists for each river gauge in the county that has a flood stage, not every flood. Flood categories use each gauge's current flood stages; crests from before levees, dams or channel changes may not be comparable. Crests measured on an old datum are left out of the rankings.

NOAA National Water Prediction Service gauge records, retrieved October 30, 2026.

High tide flooding

Tide gauges in San Luis Obispo County.

1. High tide flooding days are days on which a NOAA tide gauge recorded water at or above NOAA's minor flood threshold, set from the gauge's tide range, counted by meteorological year (May to April). These are the counts in NOAA's annual high tide flooding reports; they are not National Weather Service flood stages. Years with less than 80 percent of data are left out.

NOAA CO-OPS high tide flooding counts, through April 2026, retrieved October 30, 2026.

The drought index is for San Luis Obispo County, the county that contains Arroyo Grande.

1. The Palmer Drought Severity Index is computed by NOAA each month from the county's average temperature and precipitation, relative to the county's own climate. Zero is normal; -3 or lower is severe drought and -4 or lower extreme drought. It describes the long-term balance of moisture, not water supply or crop losses.

NOAA NCEI nClimDiv county Palmer Drought Severity Index, 1895 to September 2026, issued October 6, 2026.

Every earthquake of magnitude 4 or more within 50 miles

1. Earthquakes of magnitude 2.5 or more in the USGS Comprehensive Catalog since 1900. Within 50 miles means the epicentre lies within 50 miles of the city centre.
2. Small earthquakes were under-recorded before the modern seismic networks of the 1970s and are still missed in remote areas, so early decades read low. Magnitudes are as the catalogue reports them and mix scales (moment, local and body-wave).

USGS ANSS Comprehensive Earthquake Catalog, 1900 to present, retrieved October 30, 2026.

Tsunamis

Tsunami records for San Luis Obispo County.

1. Places where NOAA's Global Historical Tsunami Database records a tsunami's water arriving, with the greatest height it reached above sea level at the time. Only tsunamis NOAA rates probable or definite are counted. Heights from eyewitness accounts and tide gauges are mixed, and older events are less completely recorded.

NOAA NCEI/WDS Global Historical Tsunami Database, retrieved October 30, 2026.

Mapped landslides

Landslides mapped in San Luis Obispo County.

Mapped by CA GS (118), NASA (12), West Coast Slow Moving (Yuankun and others, 2021) (1).

1. Landslides mapped in the USGS compilation of landslide inventories across the United States (version 3.0, 2025), rated probable or better. The compilation joins inventories made by federal and state agencies for different purposes and areas, so the number mapped in a county reflects how closely it has been surveyed as much as how often its slopes fail. An area with few records may simply not have been mapped. Deaths are as recorded in the inventories; a slide listed in two inventories is counted once.

USGS Landslide Inventories across the United States, version 3.0, retrieved October 27, 2026.

More event types since 1996

Costliest events since 1996

1. Jan 7, 2005Heavy Rain$5.0 million
   National Weather Service narrative

   A powerful Pacific storm brought heavy rain, snow, flash flooding, high winds and landslides to Central and Southern California. During the 5 day event, rainfall totals ranged from 3 to 10 inches over coastal areas with up to 32 inches in the mountains. With such copious rainfall, flash flooding was a serious problem across Santa Barbara, Ventura and Los Angeles counties. In Santa Barbara county, flash flooding and mudslides closed Gibraltar Road at Mt. Calvary Road, stranding several vehicles, while mudslides inundated 3 homes in Lake Casitas. Across Ventura county, flash flooding and mudslides closed down Creek Road at Hermosa Road. In addition, the Ventura Beach RV Resort was…

2. Aug 17, 2002Wildfire$290,000
   National Weather Service narrative

   A wildfire burned 715 acres of forest in San Luis Obispo County, about 12 miles east of Paso Robles. The fire cost about $290,000 to fight, but resulted in no deaths or injuries.

3. Sep 24, 2025Thunderstorm Wind$2,000
   National Weather Service narrative

   Strong thunderstorms generated gusty winds around the 7400 block of Vineyard Drive in the community of Templeton. A couple trees and power lines were knocked down.

4. Oct 13, 2025Thunderstorm Wind$1,000
   National Weather Service narrative

   Strong thunderstorms generated gusty winds. A large tree was knocked down across Santa Rosa Creek Road.

5. Sep 24, 2025Thunderstorm Wind$1,000
   National Weather Service narrative

   Strong thunderstorms generated gusty winds in the community of Cambria. Law enforcement reported a tree was knocked down.

1. Storm Events records before 1996 cover only tornadoes, thunderstorm wind and hail. Damage figures are as reported by the National Weather Service at the time, not adjusted for inflation.

NOAA NCEI Storm Events Database, 1950 to 2026, issued October 26, 2026.

All-time high

110°FJun 20, 2008

All-time low

20°F2 times, most recently Dec 7, 1978

Warmest night

71°FSep 2, 2017

Coldest day

43°FDec 21, 1990

Wettest day

3.46 inMar 20, 2011

Hottest year

2014mean 63.0°F

Coldest year

1971mean 54.7°F

Wettest year

199828.24 in

Driest year

20132.99 in

Station Santa Maria Public Airport (USW00023273), 243 ft elevation, 17.6 miles from the city centre. Daily records from 1948 to October 27, 2026; 99.9% of days in the last 30 years are complete. Records at a single station can differ from a city’s official threaded record, which may combine several stations.

NOAA NCEI Global Historical Climatology Network Daily.

Declarations for San Luis Obispo County.

This product uses the Federal Emergency Management Agency's OpenFEMA API, but is not endorsed by FEMA. The Federal Government or FEMA cannot vouch for the data or analyses derived from these data after the data have been retrieved from the Agency's website(s).

OpenFEMA Disaster Declarations Summaries, retrieved October 30, 2026. Statewide declarations are not listed.

• Tornadoes NOAA Storm Prediction Center severe weather database, through 2025.
• Tropical cyclones NOAA National Hurricane Center HURDAT2 (Atlantic; Northeast and Central Pacific), through 2025.
• Wildfire USGS/USFS Monitoring Trends in Burn Severity, through 2026.
• Storm events NOAA NCEI Storm Events Database, through 2026.
• Flood insurance OpenFEMA NFIP Redacted Claims v3, refreshed August 4, 2026.
• Declarations OpenFEMA Disaster Declarations Summaries v2, retrieved October 30, 2026.
• Weather records NOAA NCEI Global Historical Climatology Network Daily, station USW00023273.
• River crests NOAA National Weather Service, National Water Prediction Service river gauges, retrieved October 30, 2026.
• Tide gauges NOAA CO-OPS high tide flooding counts, retrieved October 30, 2026.
• Drought NOAA NCEI nClimDiv county Palmer Drought Severity Index, through September 2026.
• Smoke NOAA NESDIS Hazard Mapping System smoke analysis, retrieved October 30, 2026.
• Tsunamis NOAA NCEI/WDS Global Historical Tsunami Database.
• Landslides USGS Landslide Inventories across the United States, version 3.0 (2025).
• Earthquakes USGS ANSS Comprehensive Earthquake Catalog (ComCat), retrieved October 30, 2026.

Joins, thresholds and known limits are set out in the methodology. Found an error? Report it. Page built October 30, 2026.