Weather alerts in Pima County, Arizona, 2020

197 weather alerts in 2020, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Pima County and its neighbors

Each county as a circle sized by its count in 2020. Tap one for its archive.

Alerts: 197
Warnings: 90
Watches: 25
Advisories: 56
Busiest month: August83 alerts
Busiest day: July 23, 202017 alerts

Over time

By month

Warning verification

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

Pima County, 2020

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
Tornado warnings	0			0
Severe thunderstorm warnings	36	7	81%	14	64%	14 min
Flash flood warnings	24	5	79%	9	100%	82 min

Each office's whole area, 2020

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
NWS Tucson, AZ: severe thunderstorm warnings	79	12	85%	30	57%	14 min
NWS Tucson, AZ: flash flood warnings	34	6	82%	10	100%	74 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 23, 5:00 AM MST	Dense Fog Advisory	TWC	5 hr
Feb 1, 2:58 PM MST	High Wind Watch	TWC	22 hr
Feb 2, 3:00 AM MST	Freeze Watch	TWC	24 hr
Feb 2, 3:00 AM MST	Freeze Watch	TWC	24 hr
Feb 2, 3:00 AM MST	Hard Freeze Watch	TWC	24 hr
Feb 2, 3:00 AM MST	Hard Freeze Watch	TWC	24 hr
Feb 2, 12:42 PM MST	Wind Advisory	TWC	30 hr
Feb 3, 3:23 AM MST	Freeze Warning	TWC	30 hr
Feb 3, 3:23 AM MST	Freeze Warning	TWC	54 hr
Feb 3, 3:23 AM MST	Hard Freeze Warning	TWC	54 hr
Feb 5, 3:15 AM MST	Hard Freeze Warning	TWC	30 hr
Feb 9, 2:19 PM MST	Winter Weather Advisory	TWC	58 hr
Feb 21, 10:31 AM MST	Flash Flood Watch	TWC	34 hr
Feb 22, 8:14 PM MST	Areal Flood Advisory	TWC	3 hr
Mar 8, 6:23 AM MST	Areal Flood Advisory	TWC	9 hr
Mar 17, 2:26 PM MST	Winter Weather Advisory	TWC	36 hr
Mar 18, 1:17 PM MST	Mesoscale Discussion	SPC	2 hr
Apr 18, 4:55 AM MST	Red Flag Warning	TWC	14 hr
Apr 19, 2:04 PM MST	Fire Weather Watch	TWC	36 hr
Apr 26, 1:57 PM MST	Excessive Heat Watch	TWC	24 hr
Apr 27, 1:40 PM MST	Excessive Heat Warning	TWC	3 days
May 4, 2:07 PM MST	Excessive Heat Watch	TWC	13 hr
May 5, 3:10 AM MST	Excessive Heat Warning	TWC	41 hr
May 6, 9:25 AM MST	Excessive Heat Warning	TWC	35 hr
May 9, 6:17 PM MST	Special Weather Statement	TWC	28 min
May 23, 2:36 PM MST	Excessive Heat Watch	TWC	47 hr
May 25, 1:14 PM MST	Excessive Heat Warning	TWC	6 days
May 30, 3:42 PM MST	Special Weather Statement	TWC	33 min
May 31, 12:43 PM MST	Special Weather Statement	TWC	47 min
May 31, 2:34 PM MST	Severe Thunderstorm Warning	TWC	41 min
May 31, 4:24 PM MST	Areal Flood Advisory	TWC	3 hr
Jun 1, 2:36 AM MST	Excessive Heat Watch	TWC	24 hr
Jun 1, 4:28 PM MST	Special Weather Statement	TWC	32 min
Jun 1, 5:01 PM MST	Severe Thunderstorm Warning	TWC	44 min
Jun 1, 5:21 PM MST	Areal Flood Advisory	TWC	84 min
Jun 1, 5:35 PM MST	Areal Flood Advisory	TWC	115 min
Jun 1, 5:40 PM MST	Special Weather Statement	TWC	50 min
Jun 1, 5:58 PM MST	Severe Thunderstorm Warning	TWC	47 min
Jun 1, 6:39 PM MST	Special Weather Statement	TWC	51 min
Jun 2, 2:41 AM MST	Excessive Heat Warning	TWC	4 days
Jun 15, 1:23 PM MST	Red Flag Warning	TWC	30 hr
Jun 16, 3:10 PM MST	Red Flag Warning	TWC	29 hr
Jun 26, 4:54 AM MST	Fire Weather Watch	TWC	23 hr
Jun 26, 4:54 AM MST	Fire Weather Watch	TWC	23 hr
Jun 27, 3:40 AM MST	Red Flag Warning	TWC	40 hr
Jun 27, 3:40 AM MST	Red Flag Warning	TWC	64 hr
Jun 29, 2:28 AM MST	Wind Advisory	TWC	18 hr
Jul 1, 1:47 PM MST	Flash Flood Watch	TWC	30 hr
Jul 2, 5:44 PM MST	Flash Flood Warning Considerable damage threat	TWC	110 min
Jul 6, 2:20 PM MST	Excessive Heat Watch	TWC	48 hr
Jul 8, 2:02 PM MST	Excessive Heat Warning	TWC	5 days
Jul 11, 6:37 PM MST	Severe Thunderstorm Warning	TWC	53 min
Jul 11, 7:01 PM MST	Severe Thunderstorm Warning	TWC	44 min
Jul 11, 7:06 PM MST	Dust Storm Warning	TWC	54 min
Jul 11, 7:30 PM MST	Flash Flood Warning Considerable damage threat	TWC	3 hr
Jul 11, 7:39 PM MST	Severe Thunderstorm Warning	TWC	51 min
Jul 11, 7:57 PM MST	Flash Flood Warning Considerable damage threat	TWC	2 hr
Jul 11, 8:06 PM MST	Dust Storm Warning	TWC	84 min
Jul 11, 8:23 PM MST	Severe Thunderstorm Warning	TWC	37 min
Jul 12, 7:39 PM MST	Areal Flood Advisory	TWC	77 min
Jul 15, 12:39 PM MST	Severe Thunderstorm Warning	TWC	26 min
Jul 15, 2:11 PM MST	Areal Flood Advisory	TWC	2 hr
Jul 15, 3:12 PM MST	Flash Flood Warning Considerable damage threat	TWC	3 hr
Jul 21, 1:40 PM MST	Special Weather Statement	TWC	50 min
Jul 21, 4:33 PM MST	Special Weather Statement	TWC	27 min
Jul 21, 5:02 PM MST	Special Weather Statement	TWC	43 min
Jul 22, 12:57 PM MST	Flash Flood Warning Considerable damage threat	TWC	3 hr
Jul 22, 1:35 PM MST	Flash Flood Watch	TWC	53 hr
Jul 23, 6:32 AM MST	Flash Flood Warning Considerable damage threat	TWC	118 min
Jul 23, 6:39 AM MST	Flash Flood Warning Considerable damage threat	TWC	111 min
Jul 23, 7:37 AM MST	Areal Flood Advisory	TWC	57 min
Jul 23, 7:48 AM MST	Areal Flood Advisory	TWC	2 hr
Jul 23, 7:53 AM MST	Flash Flood Warning Considerable damage threat	TWC	5 hr
Jul 23, 8:16 AM MST	Flash Flood Warning Considerable damage threat	TWC	5 hr
Jul 23, 9:03 AM MST	Severe Thunderstorm Warning	TWC	42 min
Jul 23, 9:24 AM MST	Flash Flood Warning Considerable damage threat	TWC	5 hr
Jul 23, 9:36 AM MST	Areal Flood Advisory	TWC	3 hr
Jul 23, 9:38 AM MST	Flash Flood Warning Considerable damage threat	TWC	4 hr
Jul 23, 9:45 AM MST	Areal Flood Warning	TWC	5 hr
Jul 23, 10:22 AM MST	Flash Flood Warning Considerable damage threat	TWC	3 hr
Jul 23, 11:03 AM MST	Areal Flood Advisory	TWC	5 hr
Jul 23, 11:57 AM MST	Areal Flood Advisory	TWC	3 hr
Jul 23, 11:59 AM MST	Flash Flood Warning Considerable damage threat	TWC	5 hr
Jul 23, 12:47 PM MST	Flash Flood Warning Considerable damage threat	TWC	3 hr
Jul 23, 1:49 PM MST	Areal Flood Warning	TWC	3 hr
Jul 23, 8:18 PM MST	Areal Flood Warning	TWC	6 hr
Jul 27, 2:25 AM MST	Excessive Heat Watch	TWC	24 hr
Jul 27, 1:23 PM MST	Areal Flood Advisory	TWC	2 hr
Jul 27, 3:24 PM MST	Severe Thunderstorm Warning	TWC	51 min
Jul 28, 2:30 AM MST	Excessive Heat Warning	TWC	5 days
Jul 28, 3:05 PM MST	Areal Flood Advisory	TWC	115 min
Jul 31, 5:44 PM MST	Areal Flood Advisory	TWC	107 min
Jul 31, 6:18 PM MST	Areal Flood Advisory	TWC	117 min
Jul 31, 7:14 PM MST	Flash Flood Warning Considerable damage threat	TWC	2 hr
Aug 1, 6:39 PM MST	Special Weather Statement	TWC	51 min
Aug 1, 8:37 PM MST	Areal Flood Advisory	TWC	119 min
Aug 3, 1:50 PM MST	Severe Thunderstorm Warning	TWC	40 min
Aug 3, 2:59 PM MST	Severe Thunderstorm Warning	TWC	26 min
Aug 10, 2:19 AM MST	Excessive Heat Watch	TWC	36 hr
Aug 11, 2:22 PM MST	Excessive Heat Warning	TWC	8 days
Aug 11, 3:49 PM MST	Special Weather Statement	TWC	41 min
Aug 11, 4:31 PM MST	Special Weather Statement	TWC	59 min
Aug 11, 5:28 PM MST	Special Weather Statement	TWC	62 min
Aug 12, 3:08 PM MST	Areal Flood Advisory	TWC	3 hr
Aug 13, 5:56 PM MST	Areal Flood Advisory	TWC	2 hr
Aug 15, 5:38 PM MST	Severe Thunderstorm Warning	TWC	52 min
Aug 15, 7:06 PM MST	Dust Storm Advisory	TWC	54 min
Aug 15, 8:20 PM MST	Special Weather Statement	TWC	55 min
Aug 15, 8:56 PM MST	Severe Thunderstorm Warning	TWC	26 min
Aug 16, 10:13 AM MST	Blowing Dust Advisory	TWC	11 hr
Aug 16, 1:21 PM MST	Mesoscale Discussion	SPC	114 min
Aug 16, 3:15 PM MST	Severe Thunderstorm Warning	TWC	45 min
Aug 16, 3:29 PM MST	Flash Flood Warning Considerable damage threat	TWC	2 hr
Aug 16, 3:53 PM MST	Severe Thunderstorm Warning	TWC	37 min
Aug 16, 4:11 PM MST	Dust Storm Warning	TWC	2 hr
Aug 16, 4:16 PM MST	Flash Flood Warning Considerable damage threat	TWC	119 min
Aug 16, 4:25 PM MST	Severe Thunderstorm Warning	TWC	50 min
Aug 16, 5:06 PM MST	Severe Thunderstorm Warning	TWC	39 min
Aug 16, 5:24 PM MST	Areal Flood Advisory	TWC	2 hr
Aug 16, 5:35 PM MST	Flash Flood Warning Considerable damage threat	TWC	115 min
Aug 16, 5:38 PM MST	Severe Thunderstorm Warning	TWC	37 min
Aug 16, 5:47 PM MST	Dust Storm Warning	TWC	118 min
Aug 16, 6:15 PM MST	Severe Thunderstorm Warning	TWC	45 min
Aug 16, 6:16 PM MST	Areal Flood Advisory	TWC	3 hr
Aug 16, 7:18 PM MST	Areal Flood Advisory	TWC	117 min
Aug 17, 4:48 PM MST	Mesoscale Discussion	SPC	87 min
Aug 17, 8:17 PM MST	Special Weather Statement	TWC	43 min
Aug 17, 9:28 PM MST	Severe Thunderstorm Warning	TWC	47 min
Aug 20, 3:23 PM MST	Severe Thunderstorm Warning	TWC	52 min
Aug 20, 4:17 PM MST	Severe Thunderstorm Warning	TWC	43 min
Aug 20, 4:25 PM MST	Areal Flood Advisory	TWC	110 min
Aug 20, 4:41 PM MST	Flash Flood Warning Considerable damage threat	TWC	2 hr
Aug 20, 5:07 PM MST	Dust Storm Advisory	TWC	36 min
Aug 20, 6:00 PM MST	Areal Flood Advisory	TWC	3 hr
Aug 20, 6:18 PM MST	Dust Storm Advisory	TWC	57 min
Aug 20, 6:31 PM MST	Severe Thunderstorm Warning	TWC	44 min
Aug 20, 6:38 PM MST	Areal Flood Advisory	TWC	3 hr
Aug 20, 6:51 PM MST	Dust Storm Advisory	TWC	54 min
Aug 20, 6:57 PM MST	Flash Flood Warning Considerable damage threat	TWC	2 hr
Aug 20, 7:39 PM MST	Areal Flood Advisory	TWC	111 min
Aug 20, 7:50 PM MST	Areal Flood Advisory	TWC	115 min
Aug 20, 8:05 PM MST	Flash Flood Warning Considerable damage threat	TWC	85 min
Aug 20, 8:21 PM MST	Areal Flood Advisory	TWC	92 min
Aug 20, 9:17 PM MST	Severe Thunderstorm Warning	TWC	28 min
Aug 20, 10:30 PM MST	Severe Thunderstorm Warning	TWC	60 min
Aug 20, 11:08 PM MST	Special Weather Statement	TWC	37 min
Aug 22, 2:56 AM MST	Excessive Heat Watch	TWC	23 hr
Aug 22, 9:14 PM MST	Severe Thunderstorm Warning	TWC	46 min
Aug 22, 9:25 PM MST	Areal Flood Advisory	TWC	2 hr
Aug 23, 2:19 AM MST	Excessive Heat Warning	TWC	5 days
Aug 24, 9:46 AM MST	Blowing Dust Advisory	TWC	11 hr
Aug 24, 1:37 PM MST	Special Weather Statement	TWC	38 min
Aug 25, 1:00 PM MST	Mesoscale Discussion	SPC	3 hr
Aug 26, 1:51 PM MST	Special Weather Statement	TWC	24 min
Aug 26, 2:16 PM MST	Special Weather Statement	TWC	44 min
Aug 26, 3:33 PM MST	Severe Thunderstorm Warning	TWC	42 min
Aug 26, 3:51 PM MST	Areal Flood Advisory	TWC	114 min
Aug 26, 5:49 PM MST	Areal Flood Advisory	TWC	116 min
Aug 27, 2:09 PM MST	Special Weather Statement	TWC	36 min
Aug 27, 4:04 PM MST	Areal Flood Advisory	TWC	3 hr
Aug 27, 4:07 PM MST	Special Weather Statement	TWC	38 min
Aug 27, 4:19 PM MST	Special Weather Statement	TWC	41 min
Aug 27, 4:51 PM MST	Areal Flood Advisory	TWC	114 min
Aug 28, 2:01 PM MST	Flash Flood Watch	TWC	54 hr
Aug 29, 3:22 PM MST	Areal Flood Advisory	TWC	113 min
Aug 29, 3:36 PM MST	Severe Thunderstorm Warning	TWC	39 min
Aug 29, 4:53 PM MST	Severe Thunderstorm Warning	TWC	37 min
Aug 29, 5:17 PM MST	Areal Flood Advisory	TWC	118 min
Aug 29, 5:20 PM MST	Areal Flood Advisory	TWC	3 hr
Aug 29, 5:56 PM MST	Flash Flood Warning Considerable damage threat	TWC	3 hr
Aug 29, 6:57 PM MST	Areal Flood Advisory	TWC	3 hr
Aug 29, 9:52 PM MST	Areal Flood Advisory	TWC	3 hr
Aug 30, 2:41 PM MST	Areal Flood Advisory	TWC	3 hr
Aug 31, 1:55 PM MST	Areal Flood Advisory	TWC	3 hr
Aug 31, 5:34 PM MST	Severe Thunderstorm Warning	TWC	41 min
Sep 1, 3:00 AM MST	Excessive Heat Watch	TWC	35 hr
Sep 2, 2:18 PM MST	Excessive Heat Warning	TWC	5 days
Sep 8, 5:50 PM MST	Severe Thunderstorm Warning	TWC	40 min
Sep 8, 6:08 PM MST	Areal Flood Advisory	TWC	112 min
Sep 8, 6:24 PM MST	Severe Thunderstorm Warning	TWC	51 min
Sep 8, 6:31 PM MST	Flash Flood Warning Considerable damage threat	TWC	89 min
Sep 8, 7:55 PM MST	Flash Flood Warning Considerable damage threat	TWC	3 hr
Sep 8, 9:02 PM MST	Severe Thunderstorm Warning	TWC	43 min
Sep 8, 9:37 PM MST	Severe Thunderstorm Warning	TWC	53 min
Sep 8, 10:28 PM MST	Severe Thunderstorm Warning	TWC	32 min
Oct 25, 3:11 AM MST	Freeze Watch	TWC	24 hr
Oct 25, 3:11 AM MST	Freeze Watch	TWC	24 hr
Oct 25, 3:19 PM MST	Hard Freeze Watch	TWC	12 hr
Oct 25, 3:19 PM MST	Hard Freeze Watch	TWC	12 hr
Oct 26, 3:31 AM MST	Freeze Warning	TWC	28 hr
Oct 26, 3:31 AM MST	Freeze Warning	TWC	52 hr
Oct 26, 3:31 AM MST	Hard Freeze Warning	TWC	28 hr
Oct 26, 3:31 AM MST	Hard Freeze Warning	TWC	52 hr
Nov 6, 2:03 PM MST	Wind Advisory	TWC	28 hr
Nov 8, 2:50 AM MST	Winter Weather Advisory	TWC	32 hr
Nov 29, 1:59 PM MST	Wind Advisory	TWC	22 hr
Dec 3, 4:42 AM MST	Wind Advisory	TWC	10 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	36
Mesoscale Discussion	4
Special Weather Statement	22
Flooding
Areal Flood Warning	3
Flash Flood Warning	24
Flash Flood Watch	4
Areal Flood Advisory	41
Winter
Winter Weather Advisory	3
Heat
Excessive Heat Warning	10
Excessive Heat Watch	9
Cold
Freeze Warning	4
Hard Freeze Warning	4
Freeze Watch	4
Hard Freeze Watch	4
Wind and dust
Dust Storm Warning	4
High Wind Watch	1
Blowing Dust Advisory	2
Dust Storm Advisory	4
Wind Advisory	5
Fire
Red Flag Warning	5
Fire Weather Watch	3
Fog and smoke
Dense Fog 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 2019 2021

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.