The season's first push of monsoon moisture brought scattered thunderstorms to the Mojave Desert. Some storms produced severe weather and flash flooding.
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 VEF wrote it up.
The season's first push of monsoon moisture brought scattered thunderstorms to the Mojave Desert. Some storms produced severe weather and flash flooding.
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 Las Vegas, NV wrote its last area forecast discussion before the first event at Jul 8, 6:48 PM MST, 57 minutes earlier.
Area Forecast Discussion National Weather Service Las Vegas NV 648 PM PDT Sat Jul 8 2017 .SYNOPSIS...The first significant push of monsoon moisture is expected to bring expanding thunderstorm chances to the area over the next few days. With the increasing moisture and cloud debris, daytime temperatures for Sunday and Monday are expected to be cooler before most of the area gradually warms up and drys out Tuesday onward. && .UPDATE...Scattered thunderstorms extending from Dolan Springs to south of Wikieup are slowly moving to west and are expected to move over the Colorado River Valley over the next couple of hours. The latest HRRR supports tstorm activity from this line moving to eastern San Bernardino County before diminishing. Expanded thunderstorm chances further west to account for this. -Salmen && PREVIOUS DISCUSSION...253 PM PDT... .SHORT TERM...through Monday night. Thunderstorm activity will be on the increase through Monday as monsoon moisture pushes into the area from Arizona. Precipitable water values greater than an inch currently encompass much of the SE CWA and are forecast to expand to much of the southern half of the area on Sunday and Monday. A juicer airmass is on our southern doorstep with surface dewpoint temperatures in the 50-60 degree range. A large thunderstorm complex over south central Arizona this afternoon is moving westward with the general 850-700MB flow directing it towards our area. The latest HRRR surface wind analysis and forecast suggests outflow winds from this activity as well as other convection over central Arizona reaching the eastern Mohave County border late this afternoon and spreading west into Clark County this evening. In addition, the HRRR brings thunderstorm outflow winds to Lincoln and Clark counties from storm activity over southwestern Utah which could bring storm activity to the Las Vegas Valley later this evening. All and all, it should be interesting to see how this all plays out. .LONG TERM...Tuesday through Saturday. Upper high shifts further east into the central states Tuesday- Thursday allowing southwest flow associated with Pacific Northwest trough to bring a drier/more stable air mass to parts of the region. The probability of thunderstorms decrease Tuesday-Thursday across San Bernardino County and southern Nevada, more so across Mohave County Wednesday and Thursday. The troughing influence will allow for a slight chances of thunderstorms across northern portions of Inyo and Esmeralda Counties. The models show the high center shifting west becoming established once again over northern Utah Friday/Saturday. Easterly flow south of the high center combined with an inverted trough over northwest Mexico should have low level moisture pushing back west into Mohave County by next weekend. Near to slightly above normal temperatures early-midweek will begin to rise late week. Tropical Storm Eugene in the eastern Pacific is forecast to become a Hurricane Sunday. Then Hurricane Eugene will move northwest well away from the Baja Peninsula through Monday before dissipating in colder waters by Wednesday. None of the models at this time show any injection of moisture into the region from Eugene but its something we'll be monitoring closely. Temperatures will be around normal Tuesday through Thursday, but will once again warm to around 5-7 degrees above normal by Friday as the high rebuilds back to the west. && .AVIATION...For McCarran...Gusty outflow winds will impact the airport early this evening. South winds around 20-30 kts are likely with the initial outflow boundary late this afternoon, but its possible that a second outflow boundary from Arizona will impact the terminal early this evening. Models are indicating the potential for southeast winds 20-30 kts occurring between 01-03z this evening. If they occur they would likely last through 04-05z before shifting back to the southwest with speeds around 10 kts overnight. Thunderstorms are likely to be more scattered Sunday with gusty and erratic outflow winds impacting the terminal at times during the afternoon and early evening. No operationally significant ceilings are forecast, but localized turbulence and icing hazards can be expected with any shower/thunderstorm activity. For the rest of southern Nevada, northwest Arizona and southeast California...Generally light winds following typical summertime diurnal trends expected at most terminals once again, outside of thunderstorm influences. Thunderstorms are possible once late this afternoon and evening, mainly focused on higher terrain, with low chances of impacting the terminals. Gustier winds are possible by the evening, especially east of a DAG-LAS-CDC line where consolidated thunderstorm outflow looks likely. Isolated to scattered thunderstorms are forecast Sunday with slightly better coverage. Gusty outflow winds will be the main impact, but brief heavy rain will be possible. && .FIRE WEATHER...Monsoon moisture will bring an increase in lightning activity to the area over the next few days with the initial round of storm activity possibly dropping very little rain resulting in an increasing potential for new fire starts. As moisture increases and deepens, there will be better chances for wetting rains from thunderstorms. A drying and warming trend will commence by Tuesday through the end of the week. && .HYDROLOGY...Isolated thunderstorms over the eastern Sierra over the next few days may aid snowmelt runoff and keep some drainages elevated with ongoing minor flooding possible. Remember, never drive through flooded roadways or around barricades. Also, pastureland or farmland adjacent to creeks, streams or rivers could experience areas of standing water. && .SPOTTER INFORMATION STATEMENT...Increasing monsoonal moisture will lead to increasing thunderstorm chances and cooler temperatures Sunday and Monday. Conditions are not currently forecast to be favorable for widespread flash flooding risks, however, spotters are always encouraged to report significant rainfall amounts as well as any reports of damage or flooding. && Short Term...Salmen Long Term/Aviation...Gorelow For more forecast information...see us on our webpage: http://weather.gov/lasvegas or follow us on Facebook and Twitter
The Las Vegas radar (KESX), 144 km away, was scanning. The volume nearest the first event began at 02:46 UTC.
1 thunderstorm wind, 1 lightning. Local standard time, as filed.
Several trees were blown down, at least two roofs and awnings were damaged, a large sign was knocked down, one boat was sunk, and four others had to be towed to shore.
Lightning destroyed a trailer with equipment used to sell Christmas trees.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Arizona in 2017Every state in 2017This day in weather historyWarnings in Arizona, July 2017
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: 707209, 707210.