Alert archive / Arizona

Weather alerts in Graham County, Arizona

2,420 weather alerts since 1986, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Graham County and its neighbors

Each county as a circle sized by its count since 1986. Tap one for its archive.

Alerts
2,420
Warnings
929
Watches
325
Advisories
696
Busiest year
2021214 alerts
Average year
64over 38 years on file

Over time

By year

Before late 2005 the archive holds only tornado, severe thunderstorm, flash flood and marine warnings, and from 1997 SPC's watches, so the jump that year is the archive widening, not the weather.

By month of the year

Warning verification

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

From 2008 to 2025, 0% of tornado reports in Graham County fell inside a tornado warning, and 100% of the tornado warnings had no report inside them.

Tornado warnings by year

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
2015010%
201910100%0
202410100%0

Severe thunderstorm warnings by year

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
200810460%475%25 min
20097357%560%10 min
201011191%0
201117194%250%0 min
201250100%0
201310370%250%13 min
20149189%20%
201517665%580%15 min
201611555%875%23 min
201711191%425%5 min
201810190%1100%3 min
201911282%250%3 min
202014193%520%31 min
202136489%1283%30 min
202217288%1100%4 min
202313285%425%21 min
202439587%425%25 min
202524579%3100%11 min

Flash flood warnings by year

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
20089189%250%35 min
200910100%10%
20104325%3100%14897 min
201110100%0
201210100%0
201340100%0
2014110%333%110 min
201540100%0
2016110%1100%16 min
201711282%2100%59 min
201890100%0
201930100%0
202010100%0
202118478%580%37 min
202260100%10%
202310100%0
202460100%10%
202530100%0

Years from 2008, the first full year of storm-based warnings. The year still running is on its own page.

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.

By product

Every kind of product issued here, grouped by hazard. Each opens the same place narrowed to that product.

The latest warnings

The most recent on file, newest first.

IssuedProductOfficeLasted
Sep 11, 9:20 PM MSTFlash Flood WarningTWC3 hr
Sep 9, 4:47 PM MSTSevere Thunderstorm WarningTWC43 min
Sep 3, 3:17 PM MSTFlash Flood WarningTWC3 hr
Sep 3, 2:26 PM MSTFlash Flood WarningTWC5 hr
Aug 31, 1:46 AM MSTSevere Thunderstorm WarningTWC59 min
Aug 29, 5:49 PM MSTFlash Flood Warning Considerable damage threatTWC7 hr
Aug 19, 2:15 PM MSTSevere Thunderstorm Warning Considerable damage threatTWC48 min
Aug 19, 1:33 PM MSTSevere Thunderstorm WarningTWC57 min
Aug 15, 9:12 AM MSTExtreme Heat WarningTWC14 days
Aug 13, 1:00 PM MSTFlash Flood WarningTWC3 hr
Aug 10, 9:23 PM MSTSevere Thunderstorm WarningTWC52 min
Aug 10, 8:35 PM MSTSevere Thunderstorm WarningTWC40 min

Nearby

Alerts in force nowTornadoes on recordForecastThe radar archive

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.