Alert archive / California / Orange County
Weather alerts in Orange County, California, 2020
99 weather alerts in 2020, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.
Orange County and its neighbors
Each county as a circle sized by its count in 2020. Tap one for its archive.
- Alerts
- 99
- Warnings
- 20
- Watches
- 17
- Advisories
- 47
- Busiest month
- December24 alerts
- Busiest day
- December 28, 20205 alerts
Over time
By month
Warning verification
How often warnings here had a storm report inside them, and how much warning the reports had.
Orange County, 2020
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 0 | 0 | ||||
| Severe thunderstorm warnings | 0 | 0 | ||||
| Flash flood warnings | 2 | 1 | 50% | 0 |
Each office's whole area, 2020
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS San Diego, CA: tornado warnings | 0 | 1 | 0% | |||
| NWS San Diego, CA: severe thunderstorm warnings | 9 | 0 | 100% | 4 | 0% | |
| NWS San Diego, CA: flash flood warnings | 14 | 7 | 50% | 34 | 65% | 91 min |
An office's figures cover every county it serves, including across state lines.
Verified by the Iowa Environmental Mesonet's Cow, which matches each storm-based warning with the local storm reports inside its polygon while it was in force, within 15 km of its edge: a tornado warning counts as verified on a tornado report, a severe thunderstorm warning on hail of 1 inch or more, a gust of 58 mph or more, or wind damage, a flash flood warning on a flash flood report. The false alarm ratio is the share of warnings with no such report; "inside a warning" is the probability of detection, the share of reports that fell inside one; lead time runs from the warning's issue to each report inside it, counting zero for a report that came first. A warning with no report is not proof nothing happened: reports come from spotters, the public and damage surveys, and are thin where few people live.
The alerts
Every alert, in the order issued. Times are local, Pacific Time. Each opens its own page with the text, the map, the radar and the sounding.
| Issued | Product | Office | Lasted |
|---|---|---|---|
| Jan 3, 1:00 PM PST | High Wind Watch | SGX | 24 hr |
| Jan 4, 1:00 PM PST | High Wind Warning | SGX | 49 hr |
| Jan 4, 1:00 PM PST | Wind Advisory | SGX | 56 hr |
| Jan 23, 2:56 PM PST | High Surf Advisory | SGX | 3 days |
| Jan 24, 8:10 PM PST | Dense Fog Advisory | SGX | 14 hr |
| Jan 27, 8:09 PM PST | High Wind Watch | SGX | 17 hr |
| Jan 27, 8:09 PM PST | Wind Advisory | SGX | 4 days |
| Jan 28, 1:07 PM PST | High Wind Warning | SGX | 48 hr |
| Feb 2, 1:37 AM PST | Beach Hazards Statement | SGX | 48 hr |
| Feb 3, 4:15 AM PST | High Wind Watch | SGX | 9 hr |
| Feb 3, 12:59 PM PST | Wind Advisory | SGX | 39 hr |
| Feb 5, 3:41 AM PST | Frost Advisory | SGX | 4 hr |
| Feb 9, 4:15 AM PST | Wind Advisory | SGX | 29 hr |
| Feb 10, 9:37 AM PST | High Wind Warning | SGX | 28 hr |
| Feb 22, 3:00 AM PST | Beach Hazards Statement | SGX | 13 hr |
| Feb 24, 12:09 PM PST | Wind Advisory | SGX | 72 hr |
| Feb 29, 3:03 AM PST | Wind Advisory | SGX | 57 hr |
| Mar 1, 11:48 AM PST | High Wind Watch | SGX | 14 hr |
| Mar 2, 11:57 AM PST | High Wind Warning | SGX | 24 hr |
| Mar 6, 2:38 AM PST | Dense Fog Advisory | SGX | 6 hr |
| Mar 10, 2:18 AM PDT | Beach Hazards Statement | SGX | 24 hr |
| Mar 12, 10:39 AM PDT | Areal Flood Advisory | SGX | 3 hr |
| Mar 12, 12:31 PM PDT | Areal Flood Advisory | SGX | 6 hr |
| Mar 12, 2:22 PM PDT | Flash Flood Warning | SGX | 3 hr |
| Apr 6, 8:07 AM PDT | Areal Flood Advisory | SGX | 3 hr |
| Apr 6, 10:23 AM PDT | Flash Flood Warning | SGX | 3 hr |
| Apr 6, 1:02 PM PDT | Flash Flood Watch | SGX | 4 days |
| Apr 7, 7:08 PM PDT | Areal Flood Advisory | SGX | 112 min |
| Apr 10, 3:54 AM PDT | Areal Flood Advisory | SGX | 4 hr |
| Apr 10, 7:43 AM PDT | Areal Flood Advisory | SGX | 3 hr |
| Apr 22, 1:01 PM PDT | Heat Advisory | SGX | 3 days |
| Apr 25, 6:19 PM PDT | Dense Fog Advisory | SGX | 14 hr |
| Apr 26, 8:32 PM PDT | Dense Fog Advisory | SGX | 11 hr |
| May 3, 1:22 PM PDT | Heat Advisory | SGX | 5 days |
| May 10, 1:48 AM PDT | Beach Hazards Statement | SGX | 66 hr |
| May 29, 2:04 AM PDT | Beach Hazards Statement | SGX | 60 hr |
| Jun 7, 2:35 AM PDT | Wind Advisory | SGX | 36 hr |
| Jun 7, 12:29 PM PDT | Heat Advisory | SGX | 55 hr |
| Jun 10, 2:59 AM PDT | Heat Advisory | SGX | 16 hr |
| Jul 2, 2:46 AM PDT | Beach Hazards Statement | SGX | 49 hr |
| Jul 2, 12:49 PM PDT | High Surf Advisory | SGX | 4 days |
| Jul 4, 3:40 AM PDT | Coastal Flood Advisory | SGX | 22 hr |
| Jul 9, 1:29 PM PDT | Heat Advisory | SGX | 3 days |
| Jul 29, 2:19 AM PDT | Heat Advisory | SGX | 4 days |
| Aug 2, 4:52 AM PDT | Dense Fog Advisory | SGX | 3 hr |
| Aug 11, 12:38 PM PDT | Excessive Heat Watch | SGX | 25 hr |
| Aug 12, 1:39 PM PDT | Excessive Heat Warning | SGX | 9 days |
| Sep 1, 2:44 AM PDT | Excessive Heat Watch | SGX | 33 hr |
| Sep 2, 12:12 PM PDT | Excessive Heat Warning | SGX | 5 days |
| Sep 6, 2:09 PM PDT | Fire Weather Watch | SGX | 23 hr |
| Sep 7, 1:09 PM PDT | Red Flag Warning | SGX | 55 hr |
| Sep 27, 1:10 PM PDT | Heat Advisory | SGX | 4 days |
| Sep 30, 1:30 PM PDT | Excessive Heat Warning | SGX | 55 hr |
| Sep 30, 1:30 PM PDT | Heat Advisory | SGX | 55 hr |
| Oct 11, 12:32 PM PDT | Heat Advisory | SGX | 5 days |
| Oct 14, 12:40 PM PDT | Fire Weather Watch | SGX | 21 hr |
| Oct 15, 10:00 AM PDT | Red Flag Warning | SGX | 32 hr |
| Oct 17, 1:50 AM PDT | Dense Fog Advisory | SGX | 8 hr |
| Oct 17, 9:08 PM PDT | Dense Fog Advisory | SGX | 13 hr |
| Oct 23, 1:26 PM PDT | Fire Weather Watch | SGX | 24 hr |
| Oct 23, 1:38 PM PDT | High Wind Watch | SGX | 24 hr |
| Oct 24, 1:40 PM PDT | Red Flag Warning | SGX | 3 days |
| Oct 24, 1:55 PM PDT | High Wind Warning | SGX | 3 days |
| Oct 24, 1:55 PM PDT | Wind Advisory | SGX | 51 hr |
| Oct 31, 2:33 AM PDT | Dense Fog Advisory | SGX | 6 hr |
| Nov 5, 1:30 PM PST | Beach Hazards Statement | SGX | 39 hr |
| Nov 5, 1:37 PM PST | Wind Advisory | SGX | 3 days |
| Nov 7, 4:13 AM PST | High Surf Advisory | SGX | 46 hr |
| Nov 12, 1:57 PM PST | Beach Hazards Statement | SGX | 5 days |
| Nov 22, 8:49 PM PST | Dense Fog Advisory | SGX | 6 hr |
| Nov 24, 1:26 PM PST | Fire Weather Watch | SGX | 24 hr |
| Nov 25, 1:25 PM PST | Red Flag Warning | SGX | 68 hr |
| Nov 26, 10:02 AM PST | High Wind Warning | SGX | 27 hr |
| Nov 26, 10:02 AM PST | Wind Advisory | SGX | 27 hr |
| Nov 30, 12:50 PM PST | Fire Weather Watch | SGX | 23 hr |
| Dec 1, 12:11 PM PST | Red Flag Warning | SGX | 71 hr |
| Dec 1, 12:12 PM PST | High Wind Watch | SGX | 15 hr |
| Dec 2, 2:45 AM PST | High Wind Warning | SGX | 39 hr |
| Dec 2, 5:06 PM PST | Beach Hazards Statement | SGX | 59 hr |
| Dec 4, 1:07 PM PST | Fire Weather Watch | SGX | 24 hr |
| Dec 5, 12:59 PM PST | Red Flag Warning | SGX | 3 days |
| Dec 6, 2:10 AM PST | Beach Hazards Statement | SGX | 24 hr |
| Dec 6, 1:11 PM PST | High Wind Watch | SGX | 15 hr |
| Dec 7, 1:49 AM PST | High Surf Advisory | SGX | 72 hr |
| Dec 7, 4:30 AM PST | High Wind Warning | SGX | 33 hr |
| Dec 12, 12:37 PM PST | Beach Hazards Statement | SGX | 5 days |
| Dec 21, 1:08 PM PST | Fire Weather Watch | SGX | 21 hr |
| Dec 21, 8:47 PM PST | Dense Fog Advisory | SGX | 9 hr |
| Dec 22, 9:55 AM PST | Red Flag Warning | SGX | 50 hr |
| Dec 24, 1:18 PM PST | Beach Hazards Statement | SGX | 61 hr |
| Dec 27, 1:48 AM PST | High Surf Advisory | SGX | 3 days |
| Dec 28, 1:22 AM PST | Areal Flood Advisory | SGX | 3 hr |
| Dec 28, 12:43 PM PST | Special Weather Statement | SGX | 47 min |
| Dec 28, 1:17 PM PST | Areal Flood Advisory | SGX | 3 hr |
| Dec 28, 2:58 PM PST | Special Weather Statement | SGX | 47 min |
| Dec 28, 3:51 PM PST | Special Weather Statement | SGX | 54 min |
| Dec 28, 4:08 PM PST | Areal Flood Advisory | SGX | 4 hr |
| Dec 28, 6:11 PM PST | Areal Flood Advisory | SGX | 4 hr |
| Dec 31, 2:53 AM PST | Wind Advisory | SGX | 33 hr |
By product
Every kind of product issued here, grouped by hazard. Each opens the same place narrowed to that product.
| Product | Alerts |
|---|---|
| Severe storms | |
| Special Weather Statement | 3 |
| Flooding | |
| Flash Flood Warning | 2 |
| Flash Flood Watch | 1 |
| Areal Flood Advisory | 10 |
| Heat | |
| Excessive Heat Warning | 3 |
| Excessive Heat Watch | 2 |
| Heat Advisory | 9 |
| Cold | |
| Frost Advisory | 1 |
| Wind and dust | |
| High Wind Warning | 8 |
| High Wind Watch | 7 |
| Wind Advisory | 11 |
| Fire | |
| Red Flag Warning | 7 |
| Fire Weather Watch | 7 |
| Fog and smoke | |
| Dense Fog Advisory | 10 |
| Coast and beach | |
| Coastal Flood Advisory | 1 |
| High Surf Advisory | 5 |
| Beach Hazards Statement | 12 |
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordForecastThe radar archive20192021
Sources
National Weather Service watches, warnings, advisories and statements from the Iowa Environmental Mesonet's VTEC archive, which reconstructs tornado, severe thunderstorm, flash flood and marine warnings back to 1986 from the NWS text archive. Storm Prediction Center watches and mesoscale discussions from SPC's archive through the Mesonet. County centers from the US Census Bureau. Warning verification from the Mesonet's Cow. Rebuilt daily.