An area of severe thunderstorms including a confirmed tornado occurred in Cochise County. Severe wind gusts, hail and flash flooding also occurred with these storms.
Every event with a place to put it. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS TWC wrote it up.
An area of severe thunderstorms including a confirmed tornado occurred in Cochise County. Severe wind gusts, hail and flash flooding also occurred with these storms.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Tucson, AZ wrote its last area forecast discussion before the first event at Aug 21, 9:07 AM MST, 1 hour 13 minutes earlier.
Area Forecast Discussion National Weather Service Tucson AZ 907 AM MST Wed Aug 21 2024 .SYNOPSIS...An active monsoon period through Thursday across much of southeast Arizona. Thereafter, some drying Friday into the weekend will result in isolated thunderstorms mainly east of Tucson. Thunderstorms each day will be accompanied by the typical monsoon threats of strong wind gusts, localized heavy rainfall and flash flooding, and blowing dust. High temperatures near to slightly above normal through the forecast period. && .UPDATE... This morning we've got an MCV moving into our area, sticking mainly to the south and west of Tucson, from Mexico that is bringing storms and showers along with it. The complex is moving to the northwest and will continue to bring showers for much of the morning. Outside of the MCV, to the north and east of Tucson skies are mostly sunny this morning. This afternoon, thunderstorm activity is still expected and will be stronger than this morning. With increasing PWAT's of 1-1.8 inches across the area and substantial DCAPE of 1000-2000 J/kg, storms that develop will be capable of producing strong to severe winds and locally heavy rainfall that can lead to flash flooding. Convection looks to begin around 1 to 2 PM MST focused to the south and east of Tucson becoming more widespread across southern AZ as the afternoon progresses. Chance for storms and showers in Tucson will be around 4 to 7 PM. Heat will not be as much of a concern as it was yesterday with high temperatures decreased slightly. We are in Minor HeatRisk today, meaning that only those who are extremely sensitive to heat and those who do not have a way to stay hydrated or properly cooled will be impacted. && .PREV DISCUSSION... /issued 227 AM MST Wed Aug 21 2024/ .DISCUSSION...Mostly clear skies this morning east of Tucson with partly cloudy skies west of Tucson. Radar is mostly quiet at this time with the exception of a lone shower or two over the T.O. Nation and SE Pinal County. The ingredients are coming together nicely for an active monsoon day today across much of southeast Arizona. PWAT values are trending a bit higher for much of the forecast area (1.4 to 1.8 inches from Tucson westward), though a bit drier out east near the NM border still hanging around 1 inch. We'll be under south- southeast flow aloft between high pressure over New Mexico and a trough across the west coast. While there are no discernible large scale features embedded in this flow on water vapor imagery, it's certainly likely smaller mesoscale features could help enhance lift today. Given that we'll be starting out with considerable solar insolation, that will result in destabilization with MLCAPE values per the HREF increasing to around 1000 to 2000 J/KG for much of the area later. Focus area for most widespread convection this afternoon into evening will generally be west of a Douglas-Safford line and east of a line from Sells-Eloy. Expect a hybrid of both severe threat due to strong winds (blowing dust as well W/NW of Tucson) and a flash flood threat as well. The flash flood threat will be focused on Pima and Santa Cruz Counties where the deepest moisture resides. We did consider a Flash Flood Watch but confidence is low in large scale clustering to produce widespread flash flooding with storm motions also around 15 mph. Will continue to message localized flash flooding. The Weather Prediction Center (WPC) and Storm Prediction Center (SPC) have placed our area under a slight risk for excessive rainfall and a marginal risk for severe thunderstorms, respectively. Still plenty of moisture to work with for Thursday for scattered showers and thunderstorms for most of the forecast area. A more noticeable drying trend starts on Friday as the flow aloft becomes more southwesterly which allows for additional drying aloft. Still isolated to scattered showers and thunderstorms from Tucson eastward Friday, then just isolated showers and thunderstorms south and east of Tucson this weekend. By early to mid next week, the flow pattern will become more southerly to southeasterly again allowing an increase in thunderstorm coverage back to seasonable levels for late August. Temperatures will be near to slightly above normal through the forecast period. && .AVIATION...Valid through 22/12Z. SCT clouds at 6k-9k ft AGL this morning. Aft 21/19Z, SCT-BKN clouds at 6k-9k ft AGL and SCT SHRA/TSRA for much of the forecast area thru 22/034, then diminishing thru the end of the forecast period. MVFR conditions near TSRA, with VSBY restrictions, wind gusts to 45+ kts, heavy rain and mountain obscurations. Outside of thunderstorm wind gusts, wind speeds will be 12 kts or less, favoring a SELY direction this morning, then SWLY thru NWLY direction this afternoon into evening. SFC wind variable in direction at other times. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...Mainly afternoon and evening showers and thunderstorms can be expected across southeast Arizona through Thursday, with a drying trend Friday through the weekend resulting in a reduction in thunderstorm activity. High temperatures will be near to slightly above normal through the forecast period. Min RH values will be in the 25-35 percent range in most valleys locations through Thursday, lowering to around 18-28 percent Friday through the weekend as drier air overspreads the area. Outside of any thunderstorm outflow winds, 20-foot winds will generally be 15 mph or less, with afternoon/early evening gusts to 20-25 mph and light winds overnight. && && .TWC WATCHES/WARNINGS/ADVISORIES... None. && Public...Malarkey Aviation...Aviation Forecaster Fire Weather....Fire Weather Forecaster Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson
The Tucson radar (KEMX), 66 km away, was scanning. The volume nearest the first event began at 17:20 UTC.
3 hail, 1 flash flood, 1 thunderstorm wind, 1 tornado. Local standard time, as filed.
Flooding of Nogales Wash in adjacent roadway.
Report from trained spotter of 1 inch diameter hail.
Report from trained spotter of 1.25 inch diameter hail.
Video on social media showing accumulating hail with largest hail 1.5 inch in diameter. Video also showed damage to car windshield and dents in hood and roof of car.
A personal weather station recorded a wind gust of 58 mph.
Storm chaser live streamed video of tornado in the distance. Location estimated by radar.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Arizona in 2024Every state in 2024This day in weather historyThe tornado archive for Arizona, 2024Warnings in Arizona, August 2024
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 1211528, 1211529, 1211530, 1211532, 1211537, 1211536.