Alert archive / California / Mesoscale Discussions
Mesoscale Discussions in California, 2023
17 mesoscale discussions in 2023. An alert counts here when it covered any part of the state, so the counties below add up to more than the state. The archive of mesoscale discussions reaches back to 2003.
Mesoscale Discussions by county
Each county as a circle sized by its count in 2023. Tap one for its archive.
- Mesoscale Discussions
- 17
- Busiest month
- February5 mesoscale discussions
- Busiest day
- February 24, 20232 mesoscale discussions
Over time
By month
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 | Counties | Lasted |
|---|---|---|---|---|
| Jan 9, 11:55 PM PST | Mesoscale Discussion | SPC | Marin, San Mateo, Santa Cruz, Sonoma | 4 hr |
| Feb 23, 3:09 PM PST | Mesoscale Discussion | SPC | Del Norte, Humboldt, Trinity | 6 hr |
| Feb 24, 5:18 AM PST | Mesoscale Discussion | SPC | Mariposa, Tuolumne | 4 hr |
| Feb 24, 7:00 AM PST | Mesoscale Discussion | SPC | Ventura | 4 hr |
| Feb 27, 2:17 AM PST | Mesoscale Discussion | SPC | Shasta, Siskiyou, Trinity | 5 hr |
| Feb 28, 4:27 AM PST | Mesoscale Discussion | SPC | Amador, El Dorado, Nevada, Placer | 4 hr |
| Mar 11, 12:50 PM PST | Mesoscale Discussion | SPC | Amador, Calaveras, Fresno, Madera, Mariposa, Merced and 3 more | 115 min |
| Mar 12, 1:50 PM PDT | Mesoscale Discussion | SPC | Amador, Calaveras, Fresno, Madera, Mariposa, Merced and 3 more | 2 hr |
| Mar 12, 4:49 PM PDT | Mesoscale Discussion | SPC | Fresno | 56 min |
| Mar 15, 3:23 PM PDT | Mesoscale Discussion | SPC | Riverside, San Bernardino | 3 hr |
| Jun 5, 1:26 PM PDT | Mesoscale Discussion | SPC | Butte, Glenn, Lassen, Plumas, Shasta, Siskiyou and 2 more | 2 hr |
| Jun 5, 4:43 PM PDT | Mesoscale Discussion | SPC | Fresno, Madera, Mariposa, Tuolumne | 92 min |
| Jun 6, 12:12 PM PDT | Mesoscale Discussion | SPC | Alpine, El Dorado, Nevada, Placer, Sierra | 2 hr |
| Aug 19, 1:19 PM PDT | Mesoscale Discussion | SPC | Fresno, Kern, Kings, Madera, Mariposa, Merced and 2 more | 2 hr |
| Aug 20, 11:09 AM PDT | Mesoscale Discussion | SPC | Imperial, Riverside, San Bernardino | 2 hr |
| Sep 1, 12:31 PM PDT | Mesoscale Discussion | SPC | Imperial, Riverside, San Bernardino | 2 hr |
| Dec 21, 1:56 AM PST | Mesoscale Discussion | SPC | Ventura | 94 min |
By county
Every county with at least one alert. A county page lists each alert that covered it.
- Mariposa County5
- Fresno County5
- Madera County4
- Trinity County3
- Amador County3
- Merced County3
- Stanislaus County3
- Riverside County3
- San Bernardino County3
- Tuolumne County2
- Ventura County2
- Shasta County2
- Siskiyou County2
- El Dorado County2
- Nevada County2
- Placer County2
- Calaveras County2
- Sacramento County2
- San Joaquin County2
- Imperial County2
- Marin County1
- San Mateo County1
- Santa Cruz County1
- Sonoma County1
- Del Norte County1
- Humboldt County1
- Butte County1
- Glenn County1
- Lassen County1
- Plumas County1
- Tehama County1
- Alpine County1
- Sierra County1
- Kern County1
- Kings County1
- Tulare County1
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordThe radar archive20222024
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.