Alert archive / Pennsylvania / Jefferson County
Weather alerts in Jefferson County, Pennsylvania, 2018
119 weather alerts in 2018, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.
Jefferson County and its neighbors
Each county as a circle sized by its count in 2018. Tap one for its archive.
- Alerts
- 119
- Warnings
- 41
- Watches
- 14
- Advisories
- 27
- Busiest month
- August18 alerts
- Busiest day
- October 2, 201813 alerts
Over time
By month
Warning verification
How often warnings here had a storm report inside them, and how much warning the reports had.
1 of 6 tornado warnings covering Jefferson County in 2018 had a tornado report inside them; 1 of 4 tornado reports fell inside a warning, on average 1 minutes after it went out.
Jefferson County, 2018
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 6 | 1 | 83% | 4 | 25% | 1 min |
| Severe thunderstorm warnings | 20 | 14 | 30% | 16 | 63% | 25 min |
| Flash flood warnings | 1 | 1 | 0% | 1 | 100% | 22 min |
Each office's whole area, 2018
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Pittsburgh, PA: tornado warnings | 21 | 4 | 81% | 14 | 43% | 12 min |
| NWS Pittsburgh, PA: severe thunderstorm warnings | 207 | 154 | 26% | 416 | 80% | 19 min |
| NWS Pittsburgh, PA: flash flood warnings | 79 | 54 | 32% | 204 | 84% | 62 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, Eastern Time. Each opens its own page with the text, the map, the radar and the sounding.
| Issued | Product | Office | Lasted |
|---|---|---|---|
| Jan 3, 3:42 PM EST | Wind Chill Advisory | PBZ | 4 days |
| Jan 7, 2:08 PM EST | Winter Weather Advisory | PBZ | 36 hr |
| Jan 11, 3:07 AM EST | Winter Storm Watch | PBZ | 12 hr |
| Jan 11, 12:45 PM EST | Flood Watch | PBZ | 32 hr |
| Jan 11, 3:06 PM EST | Winter Storm Warning | PBZ | 43 hr |
| Jan 12, 1:03 AM EST | Areal Flood Advisory | PBZ | 8 hr |
| Jan 12, 2:38 AM EST | Areal Flood Warning | PBZ | 12 hr |
| Jan 12, 9:40 AM EST | River Flood Warning | PBZ | 22 hr |
| Jan 12, 2:30 PM EST | Areal Flood Warning | PBZ | 3 hr |
| Jan 12, 5:21 PM EST | Areal Flood Warning | PBZ | 18 hr |
| Jan 12, 7:04 PM EST | Mesoscale Discussion | SPC | 6 hr |
| Jan 13, 1:43 PM EST | Wind Chill Advisory | PBZ | 20 hr |
| Jan 23, 2:59 AM EST | Special Weather Statement | PBZ | 61 min |
| Jan 29, 3:58 AM EST | Winter Weather Advisory | PBZ | 39 hr |
| Feb 2, 12:01 PM EST | Special Weather Statement | PBZ | 74 min |
| Feb 3, 3:18 PM EST | Winter Weather Advisory | PBZ | 24 hr |
| Feb 4, 10:16 PM EST | Special Weather Statement | PBZ | 119 min |
| Feb 6, 2:56 AM EST | Winter Weather Advisory | PBZ | 34 hr |
| Feb 6, 3:25 PM EST | Winter Storm Warning | PBZ | 24 hr |
| Feb 7, 5:28 AM EST | Mesoscale Discussion | SPC | 5 hr |
| Feb 10, 7:59 AM EST | Special Weather Statement | PBZ | 61 min |
| Feb 12, 2:16 AM EST | Special Weather Statement | PBZ | 59 min |
| Feb 16, 7:09 PM EST | Winter Weather Advisory | PBZ | 33 hr |
| Feb 21, 2:48 PM EST | Winter Weather Advisory | PBZ | 22 hr |
| Feb 22, 3:15 AM EST | Flood Watch | PBZ | 3 days |
| Mar 1, 10:10 AM EST | High Wind Watch | PBZ | 5 hr |
| Mar 1, 10:10 AM EST | High Wind Warning | PBZ | 28 hr |
| Mar 2, 1:54 AM EST | Areal Flood Warning | PBZ | 3 hr |
| Mar 6, 3:51 PM EST | Winter Weather Advisory | PBZ | 29 hr |
| Mar 7, 6:45 AM EST | Special Weather Statement | PBZ | 2 hr |
| Mar 8, 3:29 AM EST | Winter Weather Advisory | PBZ | 34 hr |
| Mar 15, 10:44 AM EDT | Snow Squall Warning | PBZ | 46 min |
| Mar 15, 11:18 AM EDT | Special Weather Statement | PBZ | 42 min |
| Mar 20, 12:06 PM EDT | Winter Weather Advisory | PBZ | 32 hr |
| Mar 28, 11:36 PM EDT | Dense Fog Advisory | PBZ | 7 hr |
| Apr 1, 1:32 PM EDT | Winter Weather Advisory | PBZ | 17 hr |
| Apr 3, 1:58 PM EDT | Wind Advisory | PBZ | 30 hr |
| Apr 3, 6:38 PM EDT | Mesoscale Discussion | SPC | 2 hr |
| Apr 7, 12:44 AM EDT | Special Weather Statement | PBZ | 61 min |
| Apr 13, 10:53 AM EDT | River Flood Watch | PBZ | 47 hr |
| Apr 27, 7:03 PM EDT | Special Weather Statement | PBZ | 42 min |
| May 3, 4:00 PM EDT | Special Weather Statement | PBZ | 60 min |
| May 4, 2:23 PM EDT | Mesoscale Discussion | SPC | 97 min |
| May 4, 2:44 PM EDT | Severe Thunderstorm Watch | SPC | 6 hr |
| May 4, 4:20 PM EDT | Mesoscale Discussion | SPC | 55 min |
| May 15, 11:43 AM EDT | Mesoscale Discussion | SPC | 3 hr |
| May 15, 11:56 AM EDT | Severe Thunderstorm Warning | PBZ | 34 min |
| May 15, 12:13 PM EDT | Special Weather Statement | PBZ | 32 min |
| May 15, 12:23 PM EDT | Severe Thunderstorm Warning | PBZ | 52 min |
| May 15, 12:26 PM EDT | Severe Thunderstorm Watch | SPC | 7 hr |
| May 15, 12:45 PM EDT | Severe Thunderstorm Warning | PBZ | 45 min |
| Jun 5, 3:05 PM EDT | Mesoscale Discussion | SPC | 2 hr |
| Jun 13, 6:10 PM EDT | Mesoscale Discussion | SPC | 95 min |
| Jun 13, 6:33 PM EDT | Severe Thunderstorm Watch | SPC | 4 hr |
| Jun 13, 6:53 PM EDT | Severe Thunderstorm Warning | PBZ | 52 min |
| Jun 13, 8:43 PM EDT | Mesoscale Discussion | SPC | 62 min |
| Jun 18, 3:19 PM EDT | Severe Thunderstorm Warning | PBZ | 26 min |
| Jun 18, 3:45 PM EDT | Severe Thunderstorm Warning | PBZ | 45 min |
| Jun 18, 4:29 PM EDT | Severe Thunderstorm Warning | PBZ | 16 min |
| Jun 18, 9:00 PM EDT | Severe Thunderstorm Warning | PBZ | 60 min |
| Jun 18, 9:27 PM EDT | Severe Thunderstorm Warning | PBZ | 63 min |
| Jun 18, 9:57 PM EDT | Severe Thunderstorm Warning | PBZ | 33 min |
| Jun 18, 10:26 PM EDT | Severe Thunderstorm Warning | PBZ | 34 min |
| Jun 18, 10:30 PM EDT | Severe Thunderstorm Warning | PBZ | 45 min |
| Jun 27, 7:37 PM EDT | Mesoscale Discussion | SPC | 3 hr |
| Jul 5, 4:10 AM EDT | Flash Flood Watch | PBZ | 19 hr |
| Jul 5, 2:50 PM EDT | Special Weather Statement | PBZ | 55 min |
| Aug 4, 6:55 AM EDT | Dense Fog Advisory | PBZ | 2 hr |
| Aug 11, 9:07 PM EDT | Areal Flood Advisory | PBZ | 113 min |
| Aug 13, 2:05 PM EDT | Areal Flood Advisory | PBZ | 115 min |
| Aug 16, 4:51 PM EDT | Special Weather Statement | PBZ | 24 min |
| Aug 16, 5:20 PM EDT | Special Weather Statement | PBZ | 25 min |
| Aug 21, 2:16 PM EDT | Mesoscale Discussion | SPC | 119 min |
| Aug 21, 2:35 PM EDT | Tornado Warning | PBZ | 25 min |
| Aug 21, 2:41 PM EDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Aug 21, 3:11 PM EDT | Severe Thunderstorm Warning | PBZ | 34 min |
| Aug 21, 3:30 PM EDT | Areal Flood Advisory | PBZ | 3 hr |
| Aug 21, 3:42 PM EDT | Areal Flood Advisory | PBZ | 3 hr |
| Aug 21, 4:04 PM EDT | Special Weather Statement | PBZ | 26 min |
| Aug 21, 4:56 PM EDT | Mesoscale Discussion | SPC | 2 hr |
| Aug 21, 7:13 PM EDT | Flash Flood Warning | PBZ | 3 hr |
| Aug 21, 8:02 PM EDT | Tornado Warning | PBZ | 28 min |
| Aug 21, 10:37 PM EDT | Areal Flood Advisory | PBZ | 2 hr |
| Aug 29, 6:40 PM EDT | Severe Thunderstorm Warning | PBZ | 35 min |
| Aug 29, 7:16 PM EDT | Special Weather Statement | PBZ | 29 min |
| Sep 3, 5:40 PM EDT | Special Weather Statement | PBZ | 50 min |
| Sep 6, 11:29 AM EDT | Special Weather Statement | PBZ | 46 min |
| Sep 8, 3:34 AM EDT | Flood Watch | PBZ | 49 hr |
| Sep 9, 4:15 PM EDT | Areal Flood Warning | PBZ | 18 hr |
| Sep 9, 9:48 PM EDT | Areal Flood Advisory | PBZ | 116 min |
| Sep 9, 11:44 PM EDT | Areal Flood Warning | PBZ | 12 hr |
| Sep 10, 3:03 PM EDT | Areal Flood Warning | PBZ | 7 hr |
| Sep 17, 3:50 AM EDT | Flood Watch | PBZ | 15 hr |
| Sep 21, 4:32 PM EDT | Severe Thunderstorm Watch | SPC | 4 hr |
| Sep 21, 7:04 PM EDT | Mesoscale Discussion | SPC | 116 min |
| Sep 21, 7:14 PM EDT | Severe Thunderstorm Warning | PBZ | 46 min |
| Sep 21, 8:15 PM EDT | Severe Thunderstorm Warning | PBZ | 45 min |
| Oct 2, 2:26 PM EDT | Mesoscale Discussion | SPC | 2 hr |
| Oct 2, 2:55 PM EDT | Tornado Watch | SPC | 8 hr |
| Oct 2, 4:16 PM EDT | Severe Thunderstorm Warning | PBZ | 13 min |
| Oct 2, 4:17 PM EDT | Severe Thunderstorm Warning | PBZ | 28 min |
| Oct 2, 4:43 PM EDT | Mesoscale Discussion | SPC | 2 hr |
| Oct 2, 4:44 PM EDT | Special Weather Statement | PBZ | 31 min |
| Oct 2, 5:03 PM EDT | Severe Thunderstorm Warning | PBZ | 42 min |
| Oct 2, 5:19 PM EDT | Tornado Warning | PBZ | 26 min |
| Oct 2, 5:36 PM EDT | Tornado Warning | PBZ | 24 min |
| Oct 2, 5:49 PM EDT | Severe Thunderstorm Warning | PBZ | 26 min |
| Oct 2, 5:59 PM EDT | Tornado Warning | PBZ | 16 min |
| Oct 2, 6:18 PM EDT | Tornado Warning | PBZ | 27 min |
| Oct 2, 7:24 PM EDT | Mesoscale Discussion | SPC | 81 min |
| Oct 13, 2:18 PM EDT | Frost Advisory | PBZ | 13 hr |
| Oct 15, 2:22 PM EDT | Frost Advisory | PBZ | 13 hr |
| Oct 17, 2:12 PM EDT | Freeze Warning | PBZ | 19 hr |
| Nov 14, 2:47 PM EST | Winter Storm Warning | PBZ | 38 hr |
| Nov 14, 2:47 PM EST | Winter Weather Advisory | PBZ | 34 hr |
| Nov 15, 9:56 AM EST | Mesoscale Discussion | SPC | 6 hr |
| Nov 15, 4:39 PM EST | Mesoscale Discussion | SPC | 6 hr |
| Nov 23, 3:46 AM EST | Winter Weather Advisory | PBZ | 32 hr |
| Nov 27, 2:00 AM EST | Winter Weather Advisory | PBZ | 32 hr |
By product
Every kind of product issued here, grouped by hazard. Each opens the same place narrowed to that product.
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordForecastThe radar archive20172019
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.