Alert archive / California / Santa Clara County
Weather alerts in Santa Clara County, California, 2016
46 weather alerts in 2016, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.
Santa Clara County and its neighbors
Each county as a circle sized by its count in 2016. Tap one for its archive.
- Alerts
- 46
- Warnings
- 6
- Watches
- 8
- Advisories
- 31
- Busiest month
- December13 alerts
- Busiest day
- December 16, 20167 alerts
Over time
By month
Warning verification
How often warnings here had a storm report inside them, and how much warning the reports had.
Santa Clara County, 2016
| 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 | 4 | 1 | 75% | 7 | 0% |
Each office's whole area, 2016
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS San Francisco Bay Area, CA: tornado warnings | 0 | 2 | 0% | |||
| NWS San Francisco Bay Area, CA: severe thunderstorm warnings | 2 | 0 | 100% | 1 | 0% | |
| NWS San Francisco Bay Area, CA: flash flood warnings | 23 | 3 | 87% | 93 | 17% | 121 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 5, 1:57 PM PST | Coastal Flood Advisory | MTR | 20 hr |
| Jan 5, 2:04 PM PST | Flash Flood Watch | MTR | 28 hr |
| Jan 6, 6:09 AM PST | Areal Flood Advisory | MTR | 3 hr |
| Jan 6, 11:38 AM PST | Areal Flood Advisory | MTR | 52 min |
| Jan 6, 1:49 PM PST | Coastal Flood Advisory | MTR | 20 hr |
| Jan 19, 4:23 AM PST | Areal Flood Advisory | MTR | 5 hr |
| Jan 21, 8:29 AM PST | Coastal Flood Advisory | MTR | 29 hr |
| Jan 21, 12:20 PM PST | Wind Advisory | MTR | 40 hr |
| Jan 22, 1:01 PM PST | Coastal Flood Advisory | MTR | 24 hr |
| Jan 31, 2:31 AM PST | Wind Advisory | MTR | 25 hr |
| Jan 31, 6:19 PM PST | Special Weather Statement | MTR | 41 min |
| Feb 16, 2:08 PM PST | Wind Advisory | MTR | 38 hr |
| Mar 4, 3:14 AM PST | Wind Advisory | MTR | 46 hr |
| Mar 5, 7:28 AM PST | Flash Flood Watch | MTR | 15 hr |
| Mar 5, 4:17 PM PST | Areal Flood Advisory | MTR | 6 hr |
| Mar 5, 10:14 PM PST | Flash Flood Watch | MTR | 5 hr |
| Mar 6, 4:57 AM PST | Wind Advisory | MTR | 23 hr |
| Mar 6, 5:16 AM PST | Flash Flood Watch | MTR | 23 hr |
| Mar 6, 9:21 PM PST | Areal Flood Advisory | MTR | 6 hr |
| Mar 6, 10:41 PM PST | Areal Flood Advisory | MTR | 5 hr |
| Mar 9, 3:18 PM PST | Flash Flood Watch | MTR | 4 days |
| Mar 11, 3:28 AM PST | Wind Advisory | MTR | 18 hr |
| Mar 13, 2:41 PM PDT | Areal Flood Advisory | MTR | 3 hr |
| Mar 13, 5:49 PM PDT | Areal Flood Advisory | MTR | 116 min |
| Apr 24, 2:25 AM PDT | Wind Advisory | MTR | 22 hr |
| Apr 29, 2:45 AM PDT | Wind Advisory | MTR | 31 hr |
| Sep 23, 10:21 AM PDT | Heat Advisory | MTR | 58 hr |
| Sep 23, 10:21 AM PDT | Heat Advisory | MTR | 3 days |
| Oct 15, 1:50 PM PDT | Flash Flood Watch | MTR | 30 hr |
| Oct 16, 7:48 AM PDT | Areal Flood Advisory | MTR | 6 hr |
| Oct 16, 10:05 AM PDT | Flash Flood Warning | MTR | 8 hr |
| Nov 13, 11:04 PM PST | Dense Fog Advisory | MTR | 11 hr |
| Nov 18, 11:22 AM PST | Wind Advisory | MTR | 27 hr |
| Dec 13, 10:00 AM PST | Flash Flood Watch | MTR | 60 hr |
| Dec 14, 4:19 AM PST | High Wind Watch | MTR | 23 hr |
| Dec 15, 3:40 AM PST | Wind Advisory | MTR | 21 hr |
| Dec 15, 4:58 PM PST | Areal Flood Advisory | MTR | 4 hr |
| Dec 15, 5:29 PM PST | Flash Flood Warning | MTR | 46 min |
| Dec 15, 6:12 PM PST | Flash Flood Warning | MTR | 3 hr |
| Dec 15, 6:38 PM PST | Flash Flood Warning | MTR | 4 hr |
| Dec 16, 7:14 AM PST | Frost Advisory | MTR | 25 hr |
| Dec 16, 7:14 AM PST | Frost Advisory | MTR | 49 hr |
| Dec 16, 7:14 AM PST | Freeze Warning | MTR | 49 hr |
| Dec 18, 12:14 PM PST | Freeze Warning | MTR | 20 hr |
| Dec 18, 7:15 PM PST | Frost Advisory | MTR | 13 hr |
| Dec 24, 2:03 AM PST | Winter Weather Advisory | MTR | 11 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 | 1 |
| Flooding | |
| Flash Flood Warning | 4 |
| Flash Flood Watch | 7 |
| Areal Flood Advisory | 10 |
| Winter | |
| Winter Weather Advisory | 1 |
| Heat | |
| Heat Advisory | 2 |
| Cold | |
| Freeze Warning | 2 |
| Frost Advisory | 3 |
| Wind and dust | |
| High Wind Watch | 1 |
| Wind Advisory | 10 |
| Fog and smoke | |
| Dense Fog Advisory | 1 |
| Coast and beach | |
| Coastal Flood Advisory | 4 |
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordForecastThe radar archive20152017
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.