The San Diego Hurricane of October 2 1858

The San Diego Hurricane of October 2, 1858 Michael Chenoweth Independent Scholar Elkridge, Maryland, USA Chris Landsea NOAA/Hurricane Research Division Miami, Florida, USA AMS Forum: Living in the Coastal Zone January 11, 2005 Acknowledgements: Kerry Emanuel for modeling results 13 January, 2001 and a NOAA/OGP grant (GC 02 -093)

Northeast Pacific Hurricane Tracks

Data Sources Available in the 1850 s • Daily weather observations by US Army surgeons at Army forts • California newspapers (Daily Alta California, Los Angeles Star) • Ship observations included in COADS • US Coast Survey notebooks

Weather Station Data in 1858

The wind force scale in use by the U. S. Army (adopted from Smithsonian Institution practices) in 1858 1. Very light breeze 2 mph (2 kt) 2. Gentle breeze 4 mph (3 kt) 3. Fresh breeze 12 mph (10 kt) 4. Strong wind 25 mph (22 kt) 5. High wind 35 mph (30 kt) 6. Gale 45 mph (39 kt) 7. Strong gale 60 mph (52 kt) 8. Violent gale 75 mph (65 kt) 9. Hurricane 90 mph (78 kt) 10. Most violent hurricane 100 mph (87 kt)

Synoptic analysis in October 1858

Atlantic Hurricane Database Re-Analysis Project http: //www. aoml. noaa. gov/hrd/data_sub/re_anal. html Added 240 tropical storms and hurricanes – 1851 -1885 Revised/added 207 tropical storms and hurricanes – 1886 -1910 1992’s Hurricane Andrew upgraded to Category 5 Remainder of 20 th Century being reanalyzed currently Picture from: "Florida's Hurricane History", by Jay Barnes

Using Peripheral Observations to Estimate the Hurricane’s Location

Estimating Intensity with and without Aircraft Reconnaissance

NEWSPAPER ACCOUNTS The Daily Alta California’s correspondent in San Diego filed the following report. “One of the most terrific and violent hurricanes that has ever been noticed by the inhabitants of our quiet city, visited us on Saturday the 2 d inst. , at daylight; the appearance of weather was ominous, and portended a sudden change of some extraordinary character; . . . Soon after this I am informed by the gentlemanly keeper of the tide gauge in this place, … that the barometer went almost immediately down several degrees lower than has ever been known in this vicinity. From this time until 11 1 -2 o'clock, A. M. , the wind gradually increased, and the whole heavens seemed closing in with bank upon bank of dark, heavy, ominouslooking clouds, fleeting pretty close down to the ground, before the increasing gale. About the time above mentioned several very heavy gusts of wind came driving madly along, completely filling the whole atmosphere with thick and impenetrable clouds of dust and sand, so much so, that one who was in the street could no more see around him than if he was surrounded by an Egyptian darkness; this continued for a considerable length of time, the violence of the wind still increasing, until about one o'clock, when it came along in a perfect hurricane, tearing down houses and everything that was in its way. Roofs of houses, trees, fences, &c. , filled the air in all directions, doing a large amount of damage, in and about the city, and its immediate vicinity. From this time until dark a continuance of the above was experienced, interspersed now and then by a crash of some house, tree, fence, or something of the kind; with the sun the wind went down; . . . The streets, alleys, and roads, from a distance as far as yet heard from, were swept as clean as if a thousand brooms had been laboriously employed for months. The scenes of the next day were unpleasant to witness; persons were standing here and there in groups, discussing and relating the effects of the storm, and the private injuries or losses sustained by them. ”

October 1858 New San Diego Observations

Weather conditions observed at the New San Diego fort on October 1 -3, 1858 Weather Element 1 st/ 0700 1 st/ 1400 1 st/ 2100 2 nd/ 0700 2 nd/ 1400 2 nd/ 2100 3 rd/ 0700 3 rd/ 1400 3 rd/ 2100 Air Temp. 70 82 74 67 74 70 64 73 67 Wind Direction E SE SE SE SW SW Wind Force 1 3 2 3 8 5 2 4 3 Barometer 30. 05 30. 02 30. 01 29. 91 29. 50 29. 79 30. 04 30. 07 30. 10 Barometer Temp. 70 81 70 66 74 70 64 72 67 Fair Cloudy Cloudy State of Sky Additional notes: Rain began 5: 00 PM on 2 October and ended an unknown time later that night. Weather Remarks for 2 October: A great storm, causing the air to be filled with dense clouds of dust, some of the houses were unroofed and blown down, trees uprooted, and fences destroyed Force 8 wind – 65 kt estimate 994 mb SLP suggests winds of at least 58 kt

1400 LT, October 2, 1858

If the hurricane would hit San Diego today … ~$500 million & Significant Loss of Live

Synthetic Tracks – MIT Hurricane Risk Study

1997’s Hurricane Linda – Projected to impact San Diego as tropical storm/Cat 1 hurricane

The San Diego Hurricane of 2 October 1858 • Newspaper accounts of storm and its impact suggest a strong tropical cyclone struck the city • Instrumental records (barometric readings and visual wind speed estimates) also are consistent with a Category 1 hurricane strike • Historical records and modeling results suggest a return interval for Category 1 conditions in San Diego of a couple hundred years – most likely during an El Nino event • Damages from such an event today would be on the order of ~$500 million and have the potential for significant loss of life