Weather alerts in Weld County, Colorado, 2016

191 weather alerts in 2016, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Weld County and its neighbors

Each county as a circle sized by its count in 2016. Tap one for its archive.

Alerts: 191
Warnings: 92
Watches: 19
Advisories: 29
Busiest month: July66 alerts
Busiest day: July 18, 201615 alerts

Over time

By month

Warning verification

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

2 of 6 tornado warnings covering Weld County in 2016 had a tornado report inside them; 1 of 4 tornado reports fell inside a warning, on average 14 minutes after it went out.

Weld County, 2016

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
Tornado warnings	6	2	67%	4	25%	14 min
Severe thunderstorm warnings	62	30	52%	56	89%	26 min
Flash flood warnings	1	0	100%	0

Each office's whole area, 2016

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
NWS Denver/Boulder, CO: tornado warnings	30	6	80%	20	60%	12 min
NWS Denver/Boulder, CO: severe thunderstorm warnings	259	94	64%	230	72%	19 min
NWS Denver/Boulder, CO: flash flood warnings	8	1	88%	3	33%	18 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, Mountain Time. Each opens its own page with the text, the map, the radar and the sounding.

Issued	Product	Office	Lasted
Jan 9, 8:13 PM MST	Dense Fog Advisory	BOU	14 hr
Jan 30, 3:14 PM MST	Winter Storm Watch	BOU	20 hr
Jan 31, 11:43 AM MST	Winter Storm Warning	BOU	52 hr
Feb 13, 4:17 AM MST	Dense Fog Advisory	BOU	5 hr
Feb 14, 3:01 PM MST	High Wind Watch	BOU	19 hr
Feb 15, 9:35 AM MST	High Wind Warning	BOU	14 hr
Feb 17, 8:38 PM MST	High Wind Watch	BOU	20 hr
Feb 17, 8:38 PM MST	High Wind Warning	BOU	32 hr
Feb 24, 9:46 AM MST	Red Flag Warning	BOU	7 hr
Feb 27, 4:21 AM MST	Red Flag Warning	BOU	15 hr
Mar 1, 3:44 AM MST	Fire Weather Watch	BOU	11 hr
Mar 1, 2:41 PM MST	Red Flag Warning	BOU	28 hr
Mar 16, 3:02 PM MDT	Winter Storm Watch	BOU	13 hr
Mar 17, 3:55 AM MDT	Winter Weather Advisory	BOU	31 hr
Mar 17, 10:57 AM MDT	Winter Storm Warning	BOU	31 hr
Mar 22, 4:48 AM MDT	Winter Weather Advisory	BOU	37 hr
Mar 22, 3:34 PM MDT	Blizzard Warning	BOU	29 hr
Mar 22, 7:30 PM MDT	Winter Storm Warning	BOU	23 hr
Mar 23, 4:33 AM MDT	Mesoscale Discussion	SPC	5 hr
Mar 28, 3:48 PM MDT	Winter Weather Advisory	BOU	50 hr
Apr 12, 3:14 PM MDT	Special Weather Statement	BOU	61 min
Apr 13, 3:28 PM MDT	Red Flag Warning	BOU	28 hr
Apr 14, 6:04 AM MDT	Winter Storm Warning	BOU	3 days
Apr 14, 1:06 PM MDT	Winter Storm Watch	BOU	16 hr
Apr 14, 1:06 PM MDT	Winter Weather Advisory	BOU	65 hr
Apr 15, 5:21 AM MDT	Winter Storm Watch	BOU	11 hr
May 6, 4:03 PM MDT	Special Weather Statement	BOU	27 min
May 7, 11:29 AM MDT	Mesoscale Discussion	SPC	91 min
May 7, 12:31 PM MDT	Tornado Watch	SPC	8 hr
May 7, 2:10 PM MDT	Severe Thunderstorm Warning	BOU	35 min
May 7, 2:14 PM MDT	Severe Thunderstorm Warning	BOU	31 min
May 7, 2:31 PM MDT	Severe Thunderstorm Warning	BOU	29 min
May 7, 2:46 PM MDT	Tornado Warning	BOU	29 min
May 7, 3:12 PM MDT	Tornado Warning	BOU	33 min
May 7, 3:36 PM MDT	Tornado Warning Tornado observed	BOU	24 min
May 7, 3:54 PM MDT	Tornado Warning	BOU	36 min
May 8, 5:57 PM MDT	Special Weather Statement	BOU	48 min
May 9, 10:15 AM MDT	River Flood Advisory	BOU	3 days
May 17, 10:34 AM MDT	River Flood Advisory	BOU	36 hr
May 17, 10:34 AM MDT	River Flood Advisory	BOU	30 hr
May 23, 10:47 AM MDT	River Flood Advisory	BOU	4 days
May 24, 11:31 AM MDT	Mesoscale Discussion	SPC	59 min
May 24, 12:45 PM MDT	Tornado Watch	SPC	7 hr
May 24, 2:30 PM MDT	Severe Thunderstorm Warning	BOU	45 min
May 24, 2:34 PM MDT	Mesoscale Discussion	SPC	86 min
May 24, 2:43 PM MDT	Severe Thunderstorm Warning	BOU	47 min
May 30, 12:49 PM MDT	Special Weather Statement	BOU	41 min
May 30, 1:56 PM MDT	Mesoscale Discussion	SPC	64 min
Jun 6, 4:29 PM MDT	Severe Thunderstorm Warning	BOU	46 min
Jun 6, 6:03 PM MDT	Severe Thunderstorm Warning	BOU	27 min
Jun 6, 6:17 PM MDT	Severe Thunderstorm Warning	BOU	28 min
Jun 6, 6:38 PM MDT	Severe Thunderstorm Warning	BOU	22 min
Jun 7, 1:37 PM MDT	Mesoscale Discussion	SPC	2 hr
Jun 10, 9:44 AM MDT	River Flood Advisory	BOU	8 days
Jun 12, 6:04 PM MDT	Areal Flood Advisory	BOU	116 min
Jun 13, 11:18 AM MDT	Mesoscale Discussion	SPC	117 min
Jun 13, 1:27 PM MDT	Tornado Watch	SPC	8 hr
Jun 13, 4:42 PM MDT	Severe Thunderstorm Warning	BOU	30 min
Jun 13, 5:10 PM MDT	Severe Thunderstorm Warning	BOU	38 min
Jun 14, 10:16 AM MDT	River Flood Advisory	BOU	27 hr
Jun 14, 10:16 AM MDT	River Flood Advisory	BOU	63 hr
Jun 23, 3:56 PM MDT	Severe Thunderstorm Warning	BOU	34 min
Jun 23, 4:30 PM MDT	Severe Thunderstorm Warning	BOU	45 min
Jun 23, 4:47 PM MDT	Severe Thunderstorm Warning	BOU	30 min
Jun 26, 4:46 PM MDT	Mesoscale Discussion	SPC	119 min
Jun 27, 12:36 PM MDT	Mesoscale Discussion	SPC	54 min
Jun 27, 1:22 PM MDT	Tornado Watch	SPC	8 hr
Jun 27, 4:00 PM MDT	Mesoscale Discussion	SPC	60 min
Jun 27, 6:44 PM MDT	Mesoscale Discussion	SPC	61 min
Jun 27, 7:47 PM MDT	Severe Thunderstorm Warning	BOU	28 min
Jun 28, 1:37 PM MDT	Severe Thunderstorm Watch	SPC	7 hr
Jun 29, 1:53 PM MDT	Special Weather Statement	BOU	37 min
Jun 29, 2:52 PM MDT	Mesoscale Discussion	SPC	53 min
Jun 29, 2:53 PM MDT	Severe Thunderstorm Warning	BOU	37 min
Jun 29, 3:20 PM MDT	Special Weather Statement	BOU	40 min
Jun 29, 3:28 PM MDT	Severe Thunderstorm Warning	BOU	30 min
Jun 29, 3:43 PM MDT	Special Weather Statement	BOU	47 min
Jun 29, 4:13 PM MDT	Severe Thunderstorm Warning	BOU	20 min
Jun 30, 2:13 PM MDT	Flash Flood Watch	BOU	10 hr
Jun 30, 2:27 PM MDT	Severe Thunderstorm Warning	BOU	19 min
Jun 30, 2:46 PM MDT	Areal Flood Advisory	BOU	3 hr
Jun 30, 3:25 PM MDT	Severe Thunderstorm Warning	BOU	35 min
Jul 1, 9:57 AM MDT	Flash Flood Watch	BOU	11 hr
Jul 1, 3:29 PM MDT	Special Weather Statement	BOU	46 min
Jul 7, 1:40 PM MDT	Mesoscale Discussion	SPC	2 hr
Jul 8, 3:02 PM MDT	Special Weather Statement	BOU	28 min
Jul 8, 4:13 PM MDT	Severe Thunderstorm Warning	BOU	32 min
Jul 8, 4:31 PM MDT	Mesoscale Discussion	SPC	59 min
Jul 8, 4:51 PM MDT	Areal Flood Advisory	BOU	84 min
Jul 8, 6:42 PM MDT	Areal Flood Advisory	BOU	2 hr
Jul 11, 3:58 AM MDT	Red Flag Warning	BOU	16 hr
Jul 16, 2:45 PM MDT	Special Weather Statement	BOU	30 min
Jul 16, 3:21 PM MDT	Special Weather Statement	BOU	24 min
Jul 17, 2:03 PM MDT	Mesoscale Discussion	SPC	57 min
Jul 17, 4:46 PM MDT	Severe Thunderstorm Warning	BOU	44 min
Jul 17, 5:23 PM MDT	Severe Thunderstorm Warning	BOU	52 min
Jul 17, 5:42 PM MDT	Tornado Warning	BOU	33 min
Jul 17, 6:11 PM MDT	Tornado Warning	BOU	34 min
Jul 17, 6:42 PM MDT	Severe Thunderstorm Warning	BOU	48 min
Jul 17, 7:45 PM MDT	Flash Flood Warning	BOU	2 hr
Jul 17, 10:04 PM MDT	Severe Thunderstorm Warning	BOU	41 min
Jul 17, 10:44 PM MDT	Severe Thunderstorm Warning	BOU	24 min
Jul 17, 10:49 PM MDT	Areal Flood Advisory	BOU	3 hr
Jul 17, 11:10 PM MDT	Severe Thunderstorm Warning	BOU	29 min
Jul 18, 3:33 PM MDT	Severe Thunderstorm Warning	BOU	42 min
Jul 18, 4:16 PM MDT	Special Weather Statement	BOU	44 min
Jul 18, 4:48 PM MDT	Special Weather Statement	BOU	42 min
Jul 18, 4:51 PM MDT	Special Weather Statement	BOU	39 min
Jul 18, 5:02 PM MDT	Severe Thunderstorm Warning	BOU	43 min
Jul 18, 5:19 PM MDT	Severe Thunderstorm Warning	BOU	41 min
Jul 18, 5:22 PM MDT	Areal Flood Advisory	BOU	3 hr
Jul 18, 5:38 PM MDT	Areal Flood Advisory	BOU	3 hr
Jul 20, 6:15 PM MDT	Areal Flood Advisory	BOU	90 min
Jul 23, 5:12 PM MDT	Special Weather Statement	BOU	48 min
Jul 24, 1:50 PM MDT	Mesoscale Discussion	SPC	115 min
Jul 24, 3:06 PM MDT	Severe Thunderstorm Warning	BOU	39 min
Jul 24, 3:44 PM MDT	Severe Thunderstorm Warning	BOU	46 min
Jul 24, 3:51 PM MDT	Severe Thunderstorm Warning	BOU	39 min
Jul 24, 4:01 PM MDT	Severe Thunderstorm Warning	BOU	44 min
Jul 24, 4:06 PM MDT	Severe Thunderstorm Warning	BOU	39 min
Jul 24, 4:25 PM MDT	Severe Thunderstorm Warning	BOU	50 min
Jul 24, 4:25 PM MDT	Severe Thunderstorm Watch	SPC	5 hr
Jul 24, 4:41 PM MDT	Severe Thunderstorm Warning	BOU	49 min
Jul 24, 4:53 PM MDT	Severe Thunderstorm Warning	BOU	37 min
Jul 24, 5:07 PM MDT	Severe Thunderstorm Warning	BOU	38 min
Jul 27, 2:41 PM MDT	Mesoscale Discussion	SPC	3 hr
Jul 27, 4:23 PM MDT	Severe Thunderstorm Warning	BOU	37 min
Jul 27, 4:54 PM MDT	Severe Thunderstorm Warning	BOU	51 min
Jul 27, 5:38 PM MDT	Severe Thunderstorm Warning	BOU	37 min
Jul 27, 6:07 PM MDT	Severe Thunderstorm Warning	BOU	24 min
Jul 28, 1:58 PM MDT	Mesoscale Discussion	SPC	2 hr
Jul 28, 6:00 PM MDT	Special Weather Statement	BOU	30 min
Jul 29, 12:34 PM MDT	Mesoscale Discussion	SPC	116 min
Jul 29, 1:08 PM MDT	Severe Thunderstorm Watch	SPC	9 hr
Jul 29, 4:35 PM MDT	Severe Thunderstorm Warning	BOU	40 min
Jul 29, 5:12 PM MDT	Severe Thunderstorm Warning	BOU	48 min
Jul 29, 5:27 PM MDT	Mesoscale Discussion	SPC	108 min
Jul 29, 5:57 PM MDT	Severe Thunderstorm Warning	BOU	63 min
Jul 29, 6:14 PM MDT	Severe Thunderstorm Warning	BOU	31 min
Jul 29, 6:41 PM MDT	Severe Thunderstorm Warning	BOU	49 min
Jul 29, 7:18 PM MDT	Severe Thunderstorm Warning	BOU	57 min
Jul 29, 8:28 PM MDT	Mesoscale Discussion	SPC	92 min
Jul 29, 8:44 PM MDT	Severe Thunderstorm Warning	BOU	31 min
Jul 29, 10:01 PM MDT	Special Weather Statement	BOU	29 min
Jul 29, 10:06 PM MDT	Severe Thunderstorm Warning	BOU	39 min
Jul 29, 11:11 PM MDT	Severe Thunderstorm Warning	BOU	49 min
Jul 30, 12:02 AM MDT	Severe Thunderstorm Warning	BOU	43 min
Jul 30, 3:48 PM MDT	Special Weather Statement	BOU	42 min
Aug 2, 1:23 PM MDT	Mesoscale Discussion	SPC	2 hr
Aug 2, 4:16 PM MDT	Severe Thunderstorm Warning	BOU	44 min
Aug 2, 5:16 PM MDT	Severe Thunderstorm Warning	BOU	44 min
Aug 7, 5:47 AM MDT	Dense Fog Advisory	BOU	4 hr
Aug 13, 7:36 PM MDT	Special Weather Statement	BOU	54 min
Aug 15, 3:27 PM MDT	Special Weather Statement	BOU	48 min
Aug 15, 4:14 PM MDT	Special Weather Statement	BOU	61 min
Aug 16, 4:56 PM MDT	Mesoscale Discussion	SPC	64 min
Aug 19, 2:37 PM MDT	Severe Thunderstorm Warning	BOU	23 min
Aug 19, 2:59 PM MDT	Severe Thunderstorm Warning	BOU	46 min
Aug 19, 3:45 PM MDT	Severe Thunderstorm Warning	BOU	45 min
Aug 19, 4:06 PM MDT	Severe Thunderstorm Warning	BOU	24 min
Aug 19, 4:29 PM MDT	Severe Thunderstorm Warning	BOU	46 min
Aug 23, 9:36 AM MDT	Red Flag Warning	BOU	8 hr
Aug 26, 2:42 PM MDT	Special Weather Statement	BOU	48 min
Aug 26, 3:23 PM MDT	Severe Thunderstorm Warning	BOU	27 min
Aug 29, 5:05 PM MDT	Areal Flood Advisory	BOU	3 hr
Sep 3, 2:39 PM MDT	Special Weather Statement	BOU	36 min
Sep 4, 4:28 PM MDT	Special Weather Statement	BOU	47 min
Sep 6, 1:34 PM MDT	Mesoscale Discussion	SPC	2 hr
Sep 14, 12:26 PM MDT	Mesoscale Discussion	SPC	3 hr
Sep 14, 5:14 PM MDT	Special Weather Statement	BOU	46 min
Sep 14, 6:46 PM MDT	Severe Thunderstorm Warning	BOU	44 min
Sep 17, 3:03 PM MDT	Red Flag Warning	BOU	28 hr
Sep 23, 1:23 PM MDT	Mesoscale Discussion	SPC	67 min
Sep 25, 3:45 PM MDT	Frost Advisory	BOU	16 hr
Oct 4, 2:56 PM MDT	Freeze Warning	BOU	18 hr
Oct 6, 4:05 AM MDT	Freeze Warning	BOU	29 hr
Oct 7, 3:29 AM MDT	Dense Fog Advisory	BOU	8 hr
Oct 15, 2:14 PM MDT	Fire Weather Watch	BOU	25 hr
Oct 15, 2:14 PM MDT	Red Flag Warning	BOU	29 hr
Oct 16, 2:51 PM MDT	Red Flag Warning	BOU	28 hr
Oct 19, 6:00 AM MDT	Freeze Watch	BOU	8 hr
Oct 19, 2:04 PM MDT	Freeze Warning	BOU	18 hr
Oct 22, 3:30 AM MDT	Red Flag Warning	BOU	15 hr
Oct 30, 3:36 AM MDT	Dense Fog Advisory	BOU	6 hr
Dec 5, 2:48 PM MST	Winter Weather Advisory	BOU	44 hr
Dec 5, 3:17 PM MST	High Wind Warning	BOU	3 hr
Dec 16, 12:58 PM MST	Wind Chill Advisory	BOU	23 hr
Dec 16, 5:57 PM MST	Wind Chill Warning	BOU	18 hr
Dec 16, 9:04 PM MST	Winter Weather Advisory	BOU	11 hr
Dec 23, 2:38 PM MST	High Wind Watch	BOU	24 hr
Dec 24, 2:39 PM MST	High Wind Warning	BOU	33 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	62
Tornado Warning	6
Severe Thunderstorm Watch	3
Tornado Watch	4
Mesoscale Discussion	26
Special Weather Statement	25
Flooding
Flash Flood Warning	1
Flash Flood Watch	2
Areal Flood Advisory	9
River Flood Advisory	7
Winter
Blizzard Warning	1
Winter Storm Warning	4
Winter Storm Watch	4
Winter Weather Advisory	6
Cold
Freeze Warning	3
Wind Chill Warning	1
Freeze Watch	1
Frost Advisory	1
Wind Chill Advisory	1
Wind and dust
High Wind Warning	4
High Wind Watch	3
Fire
Red Flag Warning	10
Fire Weather Watch	2
Fog and smoke
Dense Fog Advisory	5

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force now Tornadoes on record Forecast The radar archive 2015 2017

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.