Alert archive / Virginia / Fairfax County

Weather alerts in Fairfax County, Virginia, 2023

153 weather alerts in 2023, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Fairfax County and its neighbors

Each county as a circle sized by its count in 2023. Tap one for its archive.

Alerts: 153
Warnings: 66
Watches: 33
Advisories: 18
Busiest month: July54 alerts
Busiest day: July 29, 202311 alerts

Over time

By month

Warning verification

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

0 of 1 tornado warnings covering Fairfax County in 2023 had a tornado report inside them.

Fairfax County, 2023

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
Tornado warnings	1	0	100%	0
Severe thunderstorm warnings	42	39	7%	63	92%	15 min
Flash flood warnings	8	5	38%	8	100%	42 min

Each office's whole area, 2023

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
NWS Baltimore/Washington: tornado warnings	15	1	93%	2	50%	0 min
NWS Baltimore/Washington: severe thunderstorm warnings	370	286	23%	992	89%	21 min
NWS Baltimore/Washington: flash flood warnings	48	23	52%	47	98%	48 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
Dec 31, 11:10 PM EST	Dense Fog Advisory	LWX	10 hr
Feb 17, 3:21 PM EST	Wind Advisory	LWX	4 hr
Feb 21, 3:58 AM EST	Wind Advisory	LWX	13 hr
Mar 3, 12:33 PM EST	Wind Advisory	LWX	26 hr
Mar 13, 2:38 PM EDT	Wind Advisory	LWX	33 hr
Mar 15, 10:38 AM EDT	Wind Advisory	LWX	2 hr
Mar 25, 11:17 PM EDT	Dense Fog Advisory	LWX	5 hr
Mar 30, 3:40 AM EDT	High Wind Watch	LWX	35 hr
Mar 31, 2:29 PM EDT	High Wind Warning	LWX	35 hr
Apr 2, 1:13 PM EDT	Frost Advisory	LWX	20 hr
Apr 6, 2:00 PM EDT	Mesoscale Discussion	SPC	90 min
Apr 6, 2:58 PM EDT	Severe Thunderstorm Watch	SPC	7 hr
Apr 6, 4:44 PM EDT	Mesoscale Discussion	SPC	91 min
Apr 6, 6:08 PM EDT	Mesoscale Discussion	SPC	2 hr
Apr 6, 6:18 PM EDT	Severe Thunderstorm Warning	LWX	42 min
Apr 6, 8:27 PM EDT	Mesoscale Discussion	SPC	93 min
Apr 8, 3:21 AM EDT	Frost Advisory	LWX	30 hr
Apr 9, 9:08 AM EDT	Freeze Warning	LWX	24 hr
Apr 17, 12:25 PM EDT	Fire Weather Watch	LWX	15 hr
Apr 18, 3:14 AM EDT	Red Flag Warning	LWX	17 hr
Apr 22, 9:34 AM EDT	Mesoscale Discussion	SPC	116 min
Apr 22, 10:07 AM EDT	Severe Thunderstorm Watch	SPC	10 hr
Apr 22, 1:20 PM EDT	Severe Thunderstorm Warning	LWX	40 min
Apr 22, 2:12 PM EDT	Mesoscale Discussion	SPC	93 min
Jun 16, 1:22 PM EDT	Severe Thunderstorm Watch	SPC	8 hr
Jun 16, 4:13 PM EDT	Mesoscale Discussion	SPC	92 min
Jun 16, 5:18 PM EDT	Severe Thunderstorm Warning	LWX	42 min
Jun 23, 5:23 PM EDT	Areal Flood Warning	LWX	3 hr
Jun 26, 12:36 PM EDT	Mesoscale Discussion	SPC	2 hr
Jun 26, 2:20 PM EDT	Severe Thunderstorm Watch	SPC	9 hr
Jun 26, 4:30 PM EDT	Mesoscale Discussion	SPC	90 min
Jun 26, 8:03 PM EDT	Mesoscale Discussion	SPC	87 min
Jun 27, 2:11 PM EDT	Severe Thunderstorm Warning	LWX	49 min
Jul 1, 1:37 PM EDT	Mesoscale Discussion	SPC	113 min
Jul 2, 2:06 PM EDT	Mesoscale Discussion	SPC	114 min
Jul 2, 4:31 PM EDT	Severe Thunderstorm Watch	SPC	6 hr
Jul 3, 1:42 PM EDT	Mesoscale Discussion	SPC	2 hr
Jul 3, 2:55 PM EDT	Severe Thunderstorm Watch	SPC	7 hr
Jul 3, 4:49 PM EDT	Mesoscale Discussion	SPC	116 min
Jul 3, 5:24 PM EDT	Severe Thunderstorm Warning	LWX	40 min
Jul 4, 1:11 AM EDT	Areal Flood Warning	LWX	2 hr
Jul 5, 3:25 PM EDT	Flash Flood Warning	LWX	93 min
Jul 5, 4:59 PM EDT	Areal Flood Warning	LWX	3 hr
Jul 6, 12:48 PM EDT	Flash Flood Warning	LWX	44 min
Jul 7, 11:26 AM EDT	Flood Watch	LWX	8 hr
Jul 8, 3:23 PM EDT	Flood Watch	LWX	25 hr
Jul 9, 12:55 PM EDT	Mesoscale Discussion	SPC	65 min
Jul 9, 1:19 PM EDT	Severe Thunderstorm Watch	SPC	7 hr
Jul 13, 2:36 PM EDT	Mesoscale Discussion	SPC	2 hr
Jul 14, 2:02 PM EDT	Mesoscale Discussion	SPC	2 hr
Jul 14, 5:24 PM EDT	Severe Thunderstorm Warning	LWX	51 min
Jul 14, 5:38 PM EDT	Severe Thunderstorm Warning	LWX	52 min
Jul 14, 5:59 PM EDT	Flash Flood Warning	LWX	2 hr
Jul 14, 6:20 PM EDT	Severe Thunderstorm Warning	LWX	40 min
Jul 14, 6:37 PM EDT	Severe Thunderstorm Warning	LWX	53 min
Jul 15, 3:50 PM EDT	Mesoscale Discussion	SPC	2 hr
Jul 15, 6:38 PM EDT	Flood Watch	LWX	23 hr
Jul 15, 10:12 PM EDT	Areal Flood Warning	LWX	4 hr
Jul 19, 4:48 PM EDT	Mesoscale Discussion	SPC	87 min
Jul 25, 12:13 PM EDT	Severe Thunderstorm Watch	SPC	10 hr
Jul 25, 12:44 PM EDT	Flood Watch	LWX	9 hr
Jul 26, 9:01 AM EDT	Heat Advisory	LWX	35 hr
Jul 26, 1:57 PM EDT	Excessive Heat Watch	LWX	24 hr
Jul 27, 1:48 PM EDT	Excessive Heat Warning	LWX	29 hr
Jul 27, 3:18 PM EDT	Severe Thunderstorm Watch	SPC	5 hr
Jul 27, 4:46 PM EDT	Mesoscale Discussion	SPC	89 min
Jul 27, 6:24 PM EDT	Severe Thunderstorm Warning	LWX	32 min
Jul 27, 6:54 PM EDT	Severe Thunderstorm Warning	LWX	25 min
Jul 28, 8:33 AM EDT	Excessive Heat Warning	LWX	34 hr
Jul 28, 8:33 AM EDT	Heat Advisory	LWX	34 hr
Jul 28, 1:54 PM EDT	Mesoscale Discussion	SPC	2 hr
Jul 28, 4:48 PM EDT	Severe Thunderstorm Watch	SPC	5 hr
Jul 28, 5:43 PM EDT	Severe Thunderstorm Warning	LWX	47 min
Jul 28, 6:28 PM EDT	Severe Thunderstorm Warning	LWX	32 min
Jul 28, 6:33 PM EDT	Mesoscale Discussion	SPC	87 min
Jul 28, 7:01 PM EDT	Severe Thunderstorm Warning	LWX	59 min
Jul 28, 9:12 PM EDT	Severe Thunderstorm Warning	LWX	33 min
Jul 29, 1:56 PM EDT	Mesoscale Discussion	SPC	64 min
Jul 29, 2:48 PM EDT	Severe Thunderstorm Watch	SPC	6 hr
Jul 29, 3:40 PM EDT	Severe Thunderstorm Warning	LWX	50 min
Jul 29, 4:02 PM EDT	Severe Thunderstorm Warning	LWX	43 min
Jul 29, 4:09 PM EDT	Severe Thunderstorm Warning	LWX	21 min
Jul 29, 4:24 PM EDT	Severe Thunderstorm Warning Considerable damage threat	LWX	81 min
Jul 29, 4:37 PM EDT	Severe Thunderstorm Warning	LWX	38 min
Jul 29, 4:45 PM EDT	Mesoscale Discussion	SPC	2 hr
Jul 29, 5:00 PM EDT	Severe Thunderstorm Warning	LWX	45 min
Jul 29, 5:09 PM EDT	Severe Thunderstorm Warning Destructive damage threat	LWX	21 min
Aug 6, 2:39 PM EDT	Flood Watch	LWX	9 hr
Aug 7, 8:18 AM EDT	Mesoscale Discussion	SPC	117 min
Aug 7, 12:14 PM EDT	Mesoscale Discussion	SPC	2 hr
Aug 7, 1:20 PM EDT	Tornado Watch	SPC	11 hr
Aug 7, 3:17 PM EDT	Mesoscale Discussion	SPC	88 min
Aug 7, 4:25 PM EDT	Severe Thunderstorm Warning Considerable damage threat	LWX	50 min
Aug 7, 4:29 PM EDT	Severe Thunderstorm Warning	LWX	46 min
Aug 7, 4:40 PM EDT	Mesoscale Discussion	SPC	95 min
Aug 7, 5:11 PM EDT	Severe Thunderstorm Warning	LWX	34 min
Aug 7, 5:14 PM EDT	Severe Thunderstorm Warning	LWX	46 min
Aug 7, 5:19 PM EDT	Severe Thunderstorm Warning Destructive damage threat	LWX	26 min
Aug 7, 5:43 PM EDT	Severe Thunderstorm Warning	LWX	62 min
Aug 7, 11:37 PM EDT	Flash Flood Warning	LWX	3 hr
Aug 14, 1:55 PM EDT	Flood Watch	LWX	9 hr
Aug 14, 3:53 PM EDT	Flash Flood Warning	LWX	3 hr
Aug 14, 3:59 PM EDT	Severe Thunderstorm Warning	LWX	31 min
Aug 14, 4:02 PM EDT	Severe Thunderstorm Warning	LWX	28 min
Aug 14, 4:14 PM EDT	Flash Flood Warning	LWX	3 hr
Aug 14, 4:19 PM EDT	Tornado Warning	LWX	13 min
Aug 14, 4:25 PM EDT	Severe Thunderstorm Warning	LWX	35 min
Aug 14, 4:36 PM EDT	Flash Flood Warning Considerable damage threat	LWX	3 hr
Aug 15, 12:29 PM EDT	Flood Watch	LWX	6 hr
Aug 15, 1:28 PM EDT	Mesoscale Discussion	SPC	3 hr
Aug 15, 2:08 PM EDT	Severe Thunderstorm Watch	SPC	6 hr
Aug 15, 4:32 PM EDT	Flash Flood Warning	LWX	62 min
Aug 25, 6:36 PM EDT	Severe Thunderstorm Warning	LWX	24 min
Aug 25, 6:59 PM EDT	Severe Thunderstorm Warning	LWX	46 min
Sep 5, 12:36 AM EDT	Heat Advisory	LWX	18 hr
Sep 6, 3:11 AM EDT	Heat Advisory	LWX	16 hr
Sep 7, 11:58 AM EDT	Mesoscale Discussion	SPC	3 hr
Sep 7, 1:14 PM EDT	Severe Thunderstorm Watch	SPC	8 hr
Sep 7, 1:42 PM EDT	Severe Thunderstorm Warning	LWX	33 min
Sep 7, 2:09 PM EDT	Severe Thunderstorm Warning	LWX	51 min
Sep 7, 3:39 PM EDT	Severe Thunderstorm Warning	LWX	30 min
Sep 7, 5:16 PM EDT	Severe Thunderstorm Warning	LWX	44 min
Sep 8, 2:46 PM EDT	Mesoscale Discussion	SPC	119 min
Sep 8, 3:11 PM EDT	Severe Thunderstorm Watch	SPC	8 hr
Sep 8, 5:19 PM EDT	Severe Thunderstorm Warning	LWX	26 min
Sep 8, 5:34 PM EDT	Severe Thunderstorm Warning	LWX	26 min
Sep 8, 5:59 PM EDT	Severe Thunderstorm Warning	LWX	46 min
Sep 8, 6:34 PM EDT	Mesoscale Discussion	SPC	86 min
Sep 8, 6:39 PM EDT	Severe Thunderstorm Warning Considerable damage threat	LWX	36 min
Sep 8, 10:31 PM EDT	Mesoscale Discussion	SPC	59 min
Sep 9, 2:04 PM EDT	Flood Watch	LWX	5 hr
Sep 9, 2:08 PM EDT	Mesoscale Discussion	SPC	3 hr
Sep 9, 3:18 PM EDT	Severe Thunderstorm Warning	LWX	42 min
Sep 9, 4:23 PM EDT	Severe Thunderstorm Watch	SPC	5 hr
Sep 9, 6:06 PM EDT	Mesoscale Discussion	SPC	114 min
Sep 9, 8:08 PM EDT	Mesoscale Discussion	SPC	2 hr
Sep 21, 2:46 PM EDT	Coastal Flood Watch	LWX	31 hr
Sep 22, 4:20 AM EDT	Wind Advisory	LWX	39 hr
Sep 22, 8:50 AM EDT	Coastal Flood Advisory	LWX	69 hr
Sep 23, 2:17 PM EDT	Flood Watch	LWX	13 hr
Oct 23, 9:52 AM EDT	Frost Advisory	LWX	24 hr
Oct 31, 3:48 AM EDT	Freeze Watch	LWX	23 hr
Nov 1, 2:26 AM EDT	Freeze Warning	LWX	32 hr
Nov 17, 11:25 AM EST	Fire Weather Watch	LWX	16 hr
Dec 2, 2:13 AM EST	Dense Fog Advisory	LWX	9 hr
Dec 8, 8:16 PM EST	Flood Watch	LWX	46 hr
Dec 16, 1:32 PM EST	Flood Watch	LWX	39 hr
Dec 17, 3:51 AM EST	Wind Advisory	LWX	34 hr
Dec 17, 9:49 PM EST	Areal Flood Warning	LWX	12 hr
Dec 17, 11:12 PM EST	Areal Flood Warning	LWX	8 hr
Dec 17, 11:35 PM EST	Areal Flood Warning	LWX	7 hr
Dec 17, 11:41 PM EST	Areal Flood Warning	LWX	15 hr
Dec 17, 11:54 PM EST	Areal Flood Warning	LWX	7 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	42
Tornado Warning	1
Severe Thunderstorm Watch	15
Tornado Watch	1
Mesoscale Discussion	36
Flooding
Areal Flood Warning	9
Flash Flood Warning	8
Flood Watch	11
Heat
Excessive Heat Warning	2
Excessive Heat Watch	1
Heat Advisory	4
Cold
Freeze Warning	2
Freeze Watch	1
Frost Advisory	3
Wind and dust
High Wind Warning	1
High Wind Watch	1
Wind Advisory	7
Fire
Red Flag Warning	1
Fire Weather Watch	2
Fog and smoke
Dense Fog Advisory	3
Coast and beach
Coastal Flood Watch	1
Coastal Flood Advisory	1

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force now Tornadoes on record Forecast The radar archive 2022 2024

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.