Isolated showers and thunderstorms developed each afternoon during the weekend of 9-10 September, mainly over areas south of US-50. Subtropical moisture steadily flowing north along the western periphery of a longwave ridge centered over the US/Mexico border moistened mid-levels across southern portions of our CWA increased storm chances to 20-30%.
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 REV wrote it up.
Isolated showers and thunderstorms developed each afternoon during the weekend of 9-10 September, mainly over areas south of US-50. Subtropical moisture steadily flowing north along the western periphery of a longwave ridge centered over the US/Mexico border moistened mid-levels across southern portions of our CWA increased storm chances to 20-30%. Hazards included stronger outflow winds, frequent lightning, localized areas of heavy rainfall, and the increased chance for small hail in stronger storm cores.
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 Reno, NV wrote its last area forecast discussion before the first event at Sep 10, 12:24 PM PST, 8 hours 21 minutes earlier.
Area Forecast Discussion National Weather Service Reno NV 124 PM PDT Sun Sep 10 2023 .SYNOPSIS... Isolated to scattered showers and thunderstorms will be possible today and Monday across portions of the Sierra and W.Nevada south of US-50. Otherwise a quiet week ahead with seasonable and dry conditions with typical west breezes prevailing. && .DISCUSSION... Lingering subtropical moisture will allow isolated showers and thunderstorms to develop across Mono and Mineral counties again this afternoon (10-20% chance). Any storms that develop may be capable of producing gusty outflow winds up to 45 mph, small hail, and brief heavy rains. Expect showers and storms to diminish an hour or two after sunset with one more day of isolated to scattered shower and storms Monday afternoon mainly south of US-50. Storms that develop on Monday may be more prone to stronger outflow winds (50+ mph) as low and mid-levels dry out as subtropical moisture departs the region. After Monday, a quiet southwest flow pattern will prevail across the region for the coming week which will result in seasonable temperatures, light afternoon zephyr breezes, and mostly sunny skies outside afternoon cumulus development. Expect afternoon highs this week to warm into the mid and upper 80s across western Nevada with mid to upper 70s for Sierra communities. Overnight temperatures will be on the mild side this week with lows around 5-10 degrees above average. Fuentes && .AVIATION... The primary weather concern is afternoon showers and thunderstorms generally south of US-50 and in the vicinity of KMMH/KHTH (30-40% chance of storms within 10 miles of terminals). Timeframe to consider for showers and storms is through 03Z, broadly. Potential hazards include heavy downpours and reduced CIGS/VIS, cloud-to- ground lightning, gusty outflow winds up to 40 kts, and very small hail. A few brief showers may develop as far north as the I-80 corridor and near KMEV/KCXP/KRNO terminals in the evening, but confidence is rather low on this scenario (~10% odds). The other concern is a brief window of BCFG and periods of IFR conditions for KTRK early Monday morning, mainly between 11Z-15Z. Otherwise, VFR conditions will prevail, accompanied by typical west- northwest breezes during the afternoon. -Salas && .REV Watches/Warnings/Advisories... NV...None. CA...None. &&
The Reno radar (KRGX), 186 km away, was scanning. The volume nearest the first event began at 04:41 UTC.
1 flash flood. Local standard time, as filed.
A relayed flash flood report from Mineral County Search and Rescue. A mixture of rocks, water, mud and debris of unknown depth closed NV-359 at milepost 9. Event time based on a separate NDOT report of water on the road near the same location, or 22.0 mi S of Hawthorne, NV.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Nevada in 2023Every state in 2023This day in weather historyWarnings in Nevada, September 2023
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: 1143013.