A Pacific storm system brought widespread rain and patchy dense fog on December 4. Patchy dense fog also formed on the 5th and 6th.
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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.
A Pacific storm system brought widespread rain and patchy dense fog on December 4. Patchy dense fog also formed on the 5th and 6th.
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 Dec 4, 9:24 AM PST, 3 hours 6 minutes earlier.
Area Forecast Discussion National Weather Service Las Vegas NV 924 AM PST Wed Dec 4 2019 .SYNOPSIS...Wet day in store for much of the region with mountain snow confined to elevations above 7,000 feet. Improving conditions are expected Thursday but another system will move in late Friday into the weekend with additional mountain snow in the Sierra and light shower activity possible across the Southern Great Basin and higher terrain of the Mojave Desert. && .UPDATE...Light rain showers have picked up across southern Nevada and northwestern Arizona this morning. Light showers are expected to continue through the morning as the brunt of the moisture pushes on shore and through southeastern California. Region-wide, precipitation has begun in the form of rain, though as temperatures drop through the day in the higher elevations, precip should transition into snow in the Sierra and Spring Mountains above 7000 ft. Regarding the Owens Valley, surface temperatures remained a few degrees above freezing through the early morning hours resulting in all-liquid precip. Temperatures will continue to increase in the Owens Valley today, so chances of snowfall at this point are unlikely. Storm total rainfall amounts remain with a widespread 0.25-0.50" in the forecast. An area of focus today will be the Morongo Basin. A lot of the moisture is expected to wring out over the San Bernardino Mountains before reaching the Morongo Basin. However, spill over is possible, which would result in Yucca Valley and Morongo Valley with overachieving rainfall amounts. We will keep an eye on this and update as necessary. No changes made to the forecast this morning as it looks to be in good shape. && .PREVIOUS DISCUSSION... /issued at 201 AM PST Wed Dec 4 2019/ .SHORT TERM...through Thursday. The much anticipated storm system slated to bring widespread rain and high elevation snow to the region today is still on track. Current radar and satellite imagery indicate light, warm advection driven shower activity already breaking out across the Mojave Desert, with Daggett and Bicycle Lake both reporting light rain in the past hour. Heavier rainfall is currently moving ashore across coastal California and will gradually shift inland today. Dewpoint depressions across most of the forecast area are within ten degrees, so don't suspect it will take long to moisten the lower atmosphere and start seeing reports of measurable rainfall. Temperatures in the Owens Valley are currently hovering 1-3 degrees above the freezing mark, and suspect those temperatures will hold through the morning. As such, aside from a brief rain/snow mix this morning, anticipate most of the precipitation in the Owens Valley and near Bishop will remain in the liquid form, but will continue to monitor closely. Elsewhere, precipitation amounts were generally unchanged overnight, with a widespread 0.25-0.50" expected across the region. Given the already moist lower atmosphere and tropical origin of the incoming moisture, won't be surprised if we overachieve a bit. There could also be a few very isolated thunderstorms later this morning through the afternoon which could result in briefly heavier rain rates, though coverage looks very limited. As precipitation shield shifts east tonight, next concern will be lingering low level moisture and the potential for fog development. Retained mention of patchy dense fog for the overnight Wednesday into Thursday morning periods, especially for valley locations. Surface winds will ultimately make or break the fog potential, as some model guidance suggests winds remaining just elevated enough to limit development beyond a low stratus layer. Drier conditions resume on Thursday, though scattered clouds will linger across the area. Temperatures will hover near the seasonal average across most of the region. .LONG TERM...Friday through early next week. Another closed low is progged to reach the Pacific NW by Saturday and bring another round of Sierra snowfall Saturday through Monday morning. The orientation of this next system is quite a bit farther north and will be lacking the tropical moisture tap from earlier in the week, so valley rainfall should be considerably less impactful, if at all. However, the prospect for more winter products may be on the horizon again for the higher elevations of Inyo, Esmeralda, Nye, and Lincoln. By early next week, a rather high amplitude ridge is progged to set up over the western coast. This will likely keep weather impacts minimal through at least the middle of next week. && .HYDROLOGY...regarding the Taboose burn scar. While this next system is expecting to bring widespread rainfall to the region, rainfall rates in the vicinity of the Taboose burn scar are expected to stay relatively light. Additionally, there could be some effects due to rain falling on snow, but believe the impacts along HWY 395 should be minimally impactful given the rates expected. && .AVIATION...For McCarran...CIGS will continue to lower today as a low pressure system off the southern California coast moves inland this morning and across southern Nevada this afternoon and tonight. Expected impacts include low CIGs between 1k-1.5k feet in moderate rain beginning between 12pm-1pm and lasting through 4pm-5pm before steady rain is replaced by scattered light showers. There remains a decent chance, CIGS could drop briefly to 500-700 feet at times. Visibility during this time should generally be 3-5SM but could drop to 1-2SM at times. 2-3k foot CIGS are expected overnight into early Thursday morning with areas of fog possible within the Las Vegas Valley before conditions vastly improve later Thursday morning as the low moves further east. For the rest of southern Nevada, northwest Arizona and southeast California...A Pacific system off the southern California coast will move inland this morning and across the forecast area this afternoon and overnight. Widespread precipitation, mountain obscuration and low CIGS are expected at all terminals. Ceilings between 3-5k feet and rain will spread in from west to east between 12Z and 18Z today with the brunt of the system impacting the region this afternoon into the early evening. Precipitation coverage decreases tonight but extensive low clouds will remain in some areas. Locations that clear out could see areas of fog and low visibility develop overnight tonight and into the early morning hours on Thursday. && .SPOTTER INFORMATION STATEMENT...Another system will move across the area Today. Heavy rain, flooding, and snow reports are encouraged, as well as reports of low visibility due to fog. && UPDATE...Varian DISCUSSION...Outler AVIATION...Salmen For more forecast information...see us on our webpage: https://weather.gov/lasvegas or follow us on Facebook and Twitter
The national radar mosaic for the moment the first event began.
6 dense fog. Local standard time, as filed.
Dense fog reduced visibility to less than 1/16 of a mile in Boulder City.
Dense fog reduced visibility to less than 1/4 of a mile in Mountain Springs.
Dense fog reduced visibility to less than 1/4 mile in Mountain Springs.
Dense fog reduced visibility to 100 feet in Cal-Nev-Ari.
Dense fog reduced visibility to 100 yards in Dyer.
Dense fog reduced visibility to less than 1/4 mile in Pahrump.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Nevada in 2019Every state in 2019This day in weather historyWarnings in Nevada, December 2019
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: 869183, 869184, 869185, 869186, 869187, 869188.