Alert archive / Pennsylvania / Jefferson County

Weather alerts in Jefferson County, Pennsylvania, 2026

198 weather alerts in 2026, 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 2026. Tap one for its archive.

Alerts: 198
Warnings: 93
Watches: 31
Advisories: 29
Busiest month: July43 alerts
Busiest day: July 18, 202613 alerts

Over time

By month

Warning verification

How often warnings here had a storm report inside them, and how much warning the reports had.

3 of 5 tornado warnings covering Jefferson County in 2026 had a tornado report inside them; 5 of 5 tornado reports fell inside a warning, on average 15 minutes after it went out.

Jefferson County, 2026

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
Tornado warnings	5	3	40%	5	100%	15 min
Severe thunderstorm warnings	38	34	11%	44	86%	18 min
Flash flood warnings	17	15	12%	26	92%	67 min

Each office's whole area, 2026

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
NWS Pittsburgh, PA: tornado warnings	62	18	71%	38	74%	11 min
NWS Pittsburgh, PA: severe thunderstorm warnings	372	274	26%	1,080	89%	24 min
NWS Pittsburgh, PA: flash flood warnings	153	112	27%	358	94%	70 min

An office's figures cover every county it serves, including across state lines.

The year is still running; reports filed late and damage surveys can still change these figures.

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
Dec 31, 11:09 PM EST	Snow Squall Warning	PBZ	36 min
Dec 31, 11:26 PM EST	Mesoscale Discussion	SPC	4 hr
Dec 31, 11:38 PM EST	Snow Squall Warning	PBZ	37 min
Jan 1, 12:01 AM EST	Snow Squall Warning	PBZ	44 min
Jan 1, 12:36 AM EST	Snow Squall Warning	PBZ	39 min
Jan 11, 10:19 AM EST	Mesoscale Discussion	SPC	5 hr
Jan 11, 4:46 PM EST	Snow Squall Warning	PBZ	44 min
Jan 14, 12:23 AM EST	Winter Weather Advisory	PBZ	43 hr
Jan 16, 1:42 AM EST	Winter Weather Advisory	PBZ	40 hr
Jan 17, 11:00 AM EST	Mesoscale Discussion	SPC	4 hr
Jan 18, 1:18 PM EST	Cold Weather Advisory	PBZ	47 hr
Jan 19, 10:20 AM EST	Snow Squall Warning	PBZ	55 min
Jan 19, 10:27 AM EST	Snow Squall Warning	PBZ	63 min
Jan 19, 11:21 AM EST	Snow Squall Warning	PBZ	54 min
Jan 19, 11:29 AM EST	Snow Squall Warning	PBZ	61 min
Jan 19, 11:50 AM EST	Mesoscale Discussion	SPC	4 hr
Jan 19, 12:18 PM EST	Snow Squall Warning	PBZ	42 min
Jan 19, 1:00 PM EST	Snow Squall Warning	PBZ	75 min
Jan 19, 2:15 PM EST	Snow Squall Warning	PBZ	45 min
Jan 20, 1:33 PM EST	Winter Weather Advisory	PBZ	44 hr
Jan 21, 10:14 PM EST	Mesoscale Discussion	SPC	3 hr
Jan 22, 2:04 AM EST	Winter Storm Watch	PBZ	23 hr
Jan 22, 12:49 PM EST	Cold Weather Advisory	PBZ	45 hr
Jan 23, 12:53 AM EST	Winter Storm Warning	PBZ	3 days
Jan 25, 6:01 AM EST	Mesoscale Discussion	SPC	6 hr
Jan 25, 11:57 AM EST	Extreme Cold Watch	PBZ	12 hr
Jan 25, 11:52 PM EST	Extreme Cold Warning	PBZ	3 days
Jan 27, 12:02 AM EST	Cold Weather Advisory	PBZ	35 hr
Jan 27, 11:34 PM EST	Cold Weather Advisory	PBZ	59 hr
Jan 28, 11:48 PM EST	Cold Weather Advisory	PBZ	35 hr
Jan 29, 11:28 PM EST	Cold Weather Advisory	PBZ	36 hr
Jan 30, 10:32 PM EST	Extreme Cold Warning	PBZ	12 hr
Jan 30, 11:23 PM EST	Cold Weather Advisory	PBZ	36 hr
Feb 5, 2:09 AM EST	Extreme Cold Watch	PBZ	10 hr
Feb 5, 11:57 AM EST	Extreme Cold Warning	PBZ	70 hr
Feb 8, 12:31 PM EST	Cold Weather Advisory	PBZ	21 hr
Feb 15, 8:35 PM EST	Dense Fog Advisory	PBZ	15 hr
Feb 18, 8:13 PM EST	Dense Fog Advisory	PBZ	13 hr
Feb 19, 11:08 AM EST	Flood Watch	PBZ	46 hr
Feb 21, 12:00 PM EST	Winter Weather Advisory	PBZ	56 hr
Feb 24, 1:15 AM EST	Winter Weather Advisory	PBZ	36 hr
Mar 2, 2:10 AM EST	Winter Weather Advisory	PBZ	32 hr
Mar 3, 12:36 AM EST	Mesoscale Discussion	SPC	6 hr
Mar 3, 5:58 AM EST	Mesoscale Discussion	SPC	5 hr
Mar 4, 12:49 AM EST	Dense Fog Advisory	PBZ	10 hr
Mar 7, 1:23 PM EST	Tornado Watch	SPC	5 hr
Mar 7, 3:40 PM EST	Severe Thunderstorm Warning	PBZ	50 min
Mar 7, 3:55 PM EST	Mesoscale Discussion	SPC	2 hr
Mar 7, 4:41 PM EST	Severe Thunderstorm Warning	PBZ	28 min
Mar 7, 5:03 PM EST	Severe Thunderstorm Warning	PBZ	27 min
Mar 12, 1:38 AM EDT	Wind Advisory	PBZ	46 hr
Mar 13, 12:41 AM EDT	High Wind Warning	PBZ	28 hr
Mar 15, 1:55 AM EDT	Wind Advisory	PBZ	46 hr
Mar 16, 2:13 AM EDT	Winter Weather Advisory	PBZ	39 hr
Mar 16, 6:13 PM EDT	Mesoscale Discussion	SPC	4 hr
Mar 17, 6:35 PM EDT	Snow Squall Warning	PBZ	25 min
Mar 17, 7:01 PM EDT	Snow Squall Warning	PBZ	44 min
Mar 22, 4:44 PM EDT	Severe Thunderstorm Warning	PBZ	46 min
Mar 22, 6:36 PM EDT	Mesoscale Discussion	SPC	114 min
Mar 22, 6:46 PM EDT	Severe Thunderstorm Warning	PBZ	29 min
Mar 22, 7:28 PM EDT	Severe Thunderstorm Warning	PBZ	22 min
Mar 31, 6:26 PM EDT	Severe Thunderstorm Watch	SPC	6 hr
Mar 31, 8:57 PM EDT	Severe Thunderstorm Warning	PBZ	67 min
Mar 31, 9:58 PM EDT	Mesoscale Discussion	SPC	2 hr
Apr 3, 4:15 PM EDT	Mesoscale Discussion	SPC	2 hr
Apr 15, 2:56 PM EDT	Severe Thunderstorm Watch	SPC	6 hr
Apr 15, 4:53 PM EDT	Mesoscale Discussion	SPC	2 hr
Apr 15, 6:56 PM EDT	Severe Thunderstorm Warning Considerable damage threat	PBZ	43 min
Apr 16, 2:36 PM EDT	Mesoscale Discussion	SPC	84 min
Apr 16, 4:57 PM EDT	Mesoscale Discussion	SPC	63 min
Apr 18, 12:56 PM EDT	Freeze Watch	PBZ	12 hr
Apr 19, 12:29 AM EDT	Freeze Warning	PBZ	32 hr
Apr 19, 12:17 PM EDT	Freeze Watch	PBZ	13 hr
Apr 20, 12:48 AM EDT	Freeze Warning	PBZ	32 hr
Apr 29, 1:48 PM EDT	Mesoscale Discussion	SPC	117 min
Apr 30, 1:06 AM EDT	Frost Advisory	PBZ	32 hr
May 1, 12:53 PM EDT	Freeze Warning	PBZ	19 hr
May 2, 12:27 PM EDT	Freeze Warning	PBZ	21 hr
May 6, 12:52 PM EDT	Frost Advisory	PBZ	19 hr
May 7, 12:08 PM EDT	Frost Advisory	PBZ	20 hr
May 10, 1:20 PM EDT	Frost Advisory	PBZ	19 hr
May 10, 1:20 PM EDT	Freeze Watch	PBZ	23 hr
May 11, 12:45 PM EDT	Freeze Warning	PBZ	19 hr
May 13, 11:56 AM EDT	Mesoscale Discussion	SPC	3 hr
May 13, 2:13 PM EDT	Severe Thunderstorm Warning	PBZ	29 min
May 13, 2:14 PM EDT	Severe Thunderstorm Warning	PBZ	21 min
May 25, 2:11 AM EDT	Dense Fog Advisory	PBZ	7 hr
Jun 6, 11:07 AM EDT	Mesoscale Discussion	SPC	2 hr
Jun 6, 11:54 AM EDT	Severe Thunderstorm Watch	SPC	6 hr
Jun 6, 1:03 PM EDT	Mesoscale Discussion	SPC	87 min
Jun 11, 12:27 PM EDT	Mesoscale Discussion	SPC	2 hr
Jun 11, 1:20 PM EDT	Severe Thunderstorm Watch	SPC	6 hr
Jun 11, 3:46 PM EDT	Severe Thunderstorm Warning Considerable damage threat	PBZ	59 min
Jun 11, 3:48 PM EDT	Mesoscale Discussion	SPC	117 min
Jun 11, 3:55 PM EDT	Severe Thunderstorm Warning	PBZ	65 min
Jun 11, 4:41 PM EDT	Severe Thunderstorm Warning Considerable damage threat	PBZ	29 min
Jun 14, 1:25 PM EDT	Severe Thunderstorm Watch	SPC	8 hr
Jun 14, 4:20 PM EDT	Tornado Warning	PBZ	40 min
Jun 14, 4:52 PM EDT	Mesoscale Discussion	SPC	113 min
Jun 14, 5:41 PM EDT	Tornado Watch	SPC	4 hr
Jun 14, 5:51 PM EDT	Severe Thunderstorm Warning	PBZ	54 min
Jun 14, 5:54 PM EDT	Tornado Warning	PBZ	41 min
Jun 14, 5:54 PM EDT	Mesoscale Discussion	SPC	96 min
Jun 14, 6:44 PM EDT	Severe Thunderstorm Warning	PBZ	76 min
Jun 21, 4:03 AM EDT	Dense Fog Advisory	PBZ	4 hr
Jun 25, 5:02 PM EDT	Severe Thunderstorm Warning	PBZ	40 min
Jun 25, 5:52 PM EDT	Mesoscale Discussion	SPC	23 min
Jun 25, 5:56 PM EDT	Severe Thunderstorm Watch	SPC	4 hr
Jun 25, 8:43 PM EDT	Mesoscale Discussion	SPC	62 min
Jun 29, 12:53 PM EDT	Heat Advisory	PBZ	5 days
Jun 30, 1:30 AM EDT	Extreme Heat Warning	PBZ	5 days
Jul 3, 12:25 PM EDT	Mesoscale Discussion	SPC	2 hr
Jul 3, 3:25 PM EDT	Severe Thunderstorm Watch	SPC	7 hr
Jul 3, 4:07 PM EDT	Severe Thunderstorm Warning	PBZ	23 min
Jul 3, 8:37 PM EDT	Severe Thunderstorm Warning	PBZ	38 min
Jul 3, 9:04 PM EDT	Severe Thunderstorm Warning	PBZ	26 min
Jul 3, 9:17 PM EDT	Severe Thunderstorm Warning	PBZ	31 min
Jul 3, 9:30 PM EDT	Severe Thunderstorm Warning	PBZ	15 min
Jul 3, 9:53 PM EDT	Severe Thunderstorm Warning	PBZ	23 min
Jul 3, 11:33 PM EDT	Severe Thunderstorm Warning	PBZ	42 min
Jul 4, 1:36 PM EDT	Mesoscale Discussion	SPC	2 hr
Jul 4, 1:59 PM EDT	Severe Thunderstorm Watch	SPC	6 hr
Jul 4, 4:26 PM EDT	Severe Thunderstorm Warning	PBZ	70 min
Jul 4, 4:48 PM EDT	Severe Thunderstorm Warning	PBZ	30 min
Jul 5, 2:44 AM EDT	Dense Fog Advisory	PBZ	6 hr
Jul 5, 11:03 AM EDT	Flood Watch	PBZ	11 hr
Jul 5, 3:51 PM EDT	Flash Flood Warning	PBZ	3 hr
Jul 5, 4:17 PM EDT	Flash Flood Warning	PBZ	3 hr
Jul 6, 2:09 AM EDT	Flood Watch	PBZ	21 hr
Jul 6, 5:58 PM EDT	Flash Flood Warning	PBZ	107 min
Jul 6, 5:58 PM EDT	Mesoscale Discussion	SPC	2 hr
Jul 6, 7:24 PM EDT	Flash Flood Warning	PBZ	2 hr
Jul 6, 8:51 PM EDT	Flash Flood Warning	PBZ	2 hr
Jul 10, 1:56 AM EDT	Flood Watch	PBZ	20 hr
Jul 10, 3:04 PM EDT	Flash Flood Warning	PBZ	2 hr
Jul 18, 9:42 AM EDT	Flood Watch	PBZ	13 hr
Jul 18, 12:18 PM EDT	Mesoscale Discussion	SPC	117 min
Jul 18, 1:02 PM EDT	Severe Thunderstorm Watch	SPC	8 hr
Jul 18, 3:50 PM EDT	Severe Thunderstorm Warning	PBZ	55 min
Jul 18, 3:56 PM EDT	Tornado Warning	PBZ	34 min
Jul 18, 4:27 PM EDT	Tornado Warning	PBZ	48 min
Jul 18, 4:41 PM EDT	Flash Flood Warning	PBZ	5 hr
Jul 18, 5:33 PM EDT	Severe Thunderstorm Warning	PBZ	38 min
Jul 18, 6:47 PM EDT	Mesoscale Discussion	SPC	118 min
Jul 18, 7:03 PM EDT	Flash Flood Warning	PBZ	3 hr
Jul 18, 7:05 PM EDT	Severe Thunderstorm Warning	PBZ	55 min
Jul 18, 7:11 PM EDT	Flash Flood Warning	PBZ	3 hr
Jul 18, 7:52 PM EDT	Severe Thunderstorm Warning	PBZ	38 min
Jul 18, 8:27 PM EDT	Flash Flood Warning	PBZ	94 min
Jul 18, 9:42 PM EDT	Areal Flood Warning	PBZ	11 hr
Jul 18, 9:46 PM EDT	Areal Flood Warning	PBZ	11 hr
Jul 18, 10:01 PM EDT	Areal Flood Warning	PBZ	8 hr
Jul 21, 7:13 PM EDT	Severe Thunderstorm Warning Considerable damage threat	PBZ	47 min
Jul 21, 7:26 PM EDT	Tornado Warning	PBZ	34 min
Aug 2, 2:04 AM EDT	Flood Watch	PBZ	21 hr
Aug 7, 9:28 AM EDT	Flash Flood Warning	PBZ	3 hr
Aug 7, 11:45 AM EDT	Flash Flood Warning	PBZ	94 min
Aug 7, 12:27 PM EDT	Areal Flood Warning	PBZ	6 hr
Aug 7, 1:17 PM EDT	Areal Flood Warning	PBZ	6 hr
Aug 7, 1:19 PM EDT	Areal Flood Warning	PBZ	6 hr
Aug 8, 5:54 PM EDT	Mesoscale Discussion	SPC	2 hr
Aug 8, 8:39 PM EDT	Severe Thunderstorm Warning	PBZ	66 min
Aug 10, 8:41 AM EDT	Mesoscale Discussion	SPC	2 hr
Aug 10, 9:29 AM EDT	Severe Thunderstorm Watch	SPC	6 hr
Aug 16, 1:05 PM EDT	Severe Thunderstorm Watch	SPC	9 hr
Aug 16, 7:17 PM EDT	Flash Flood Warning	PBZ	3 hr
Aug 20, 9:59 AM EDT	Flash Flood Warning	PBZ	3 hr
Aug 20, 11:29 AM EDT	Flash Flood Warning	PBZ	3 hr
Aug 20, 2:12 PM EDT	Areal Flood Warning	PBZ	3 hr
Aug 21, 1:50 AM EDT	Dense Fog Advisory	PBZ	7 hr
Aug 22, 11:38 AM EDT	Mesoscale Discussion	SPC	3 hr
Aug 22, 1:22 PM EDT	Severe Thunderstorm Watch	SPC	8 hr
Aug 22, 6:59 PM EDT	Flash Flood Warning	PBZ	3 hr
Aug 22, 7:00 PM EDT	Mesoscale Discussion	SPC	90 min
Aug 22, 7:01 PM EDT	Severe Thunderstorm Warning	PBZ	34 min
Sep 1, 6:00 PM EDT	Mesoscale Discussion	SPC	90 min
Sep 1, 6:40 PM EDT	Severe Thunderstorm Warning Considerable damage threat	PBZ	73 min
Sep 2, 8:36 AM EDT	Severe Thunderstorm Warning	PBZ	54 min
Sep 2, 8:51 AM EDT	Mesoscale Discussion	SPC	84 min
Sep 2, 9:27 AM EDT	Severe Thunderstorm Warning	PBZ	48 min
Sep 2, 3:58 PM EDT	Mesoscale Discussion	SPC	92 min
Sep 2, 4:56 PM EDT	Severe Thunderstorm Watch	SPC	9 hr
Sep 2, 5:53 PM EDT	Severe Thunderstorm Warning	PBZ	26 min
Sep 2, 8:48 PM EDT	Mesoscale Discussion	SPC	87 min
Sep 3, 2:07 AM EDT	Mesoscale Discussion	SPC	113 min
Sep 3, 3:05 AM EDT	Flash Flood Warning	PBZ	3 hr
Sep 3, 11:15 AM EDT	Flood Watch	PBZ	11 hr
Sep 3, 3:03 PM EDT	Severe Thunderstorm Watch	SPC	9 hr
Sep 3, 4:16 PM EDT	Mesoscale Discussion	SPC	119 min
Sep 3, 5:12 PM EDT	Severe Thunderstorm Warning Considerable damage threat	PBZ	48 min
Sep 9, 2:06 PM EDT	Mesoscale Discussion	SPC	84 min
Sep 9, 2:51 PM EDT	Severe Thunderstorm Watch	SPC	8 hr
Sep 9, 4:42 PM EDT	Mesoscale Discussion	SPC	93 min
Sep 11, 1:26 PM EDT	Flood Watch	PBZ	40 hr
Sep 12, 2:22 PM EDT	Mesoscale Discussion	SPC	113 min
Sep 12, 4:20 PM EDT	Severe Thunderstorm Warning	PBZ	55 min
Sep 12, 7:48 PM EDT	Areal Flood Warning	PBZ	3 hr
Sep 13, 3:59 PM EDT	Mesoscale Discussion	SPC	2 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
Severe Thunderstorm Warning	38
Tornado Warning	5
Severe Thunderstorm Watch	15
Tornado Watch	2
Mesoscale Discussion	45
Flooding
Areal Flood Warning	8
Flash Flood Warning	17
Flood Watch	8
Winter
Snow Squall Warning	14
Winter Storm Warning	1
Winter Storm Watch	1
Winter Weather Advisory	7
Heat
Extreme Heat Warning	1
Heat Advisory	1
Cold
Extreme Cold Warning	3
Freeze Warning	5
Extreme Cold Watch	2
Freeze Watch	3
Cold Weather Advisory	8
Frost Advisory	4
Wind and dust
High Wind Warning	1
Wind Advisory	2
Fog and smoke
Dense Fog Advisory	7

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force now Tornadoes on record Forecast The radar archive 2025

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.