Spring Valley, NV 89113 Weather

Key messages

* Dry and seasonable conditions continue through Thursday.

* Precipitation chances and cooler temperatures return to the region late this week and continue through the weekend.

Discussion

Today through Tuesday.

Expect a couple more days of pleasant weather before the next system moves in towards the end of the week. Zonal flow aloft continues to maintain partly to mostly cloudy skies and temperatures within a few degrees of normal for late October. This means highs in the upper 70s for Las Vegas, the low 80s in the Colorado River Valley, and the upper 60s to low 70s in Owens Valley.

An incoming system will bring precipitation, gusty winds, and cooler temperatures to the forecast area in a few days. A trough will settle off the West Coast starting Thursday, a favorable position to draw moisture from Tropical Storm Vance up the Gulf of California and into the Desert Southwest. PWATs rise to over 200 percent of normal for this time of year. This setup results in precipitation chances across northwestern Arizona, parts of southern Nevada, and eastern California near the Colorado River as early as Thursday night, lasting into Saturday. Heightened instability with CAPE up to 500 J/kg may lead to particularly efficient rain rates in southern Mohave County on Friday afternoon. However, more widespread precipitation potential arrives late Saturday through Sunday as the trough moves inland, splitting as it tracks east into one low over the Pacific Northwest and another over Southern California. The southern feature will draw subtropical moisture into the region, but trajectory of the moisture will be a major factor in which areas receive precipitation. Southwesterly flow and rain shadowing behind the San Bernardino Mountains could greatly reduce rainfall for sections of the Mojave Desert. Areas further to the east seem to have better precipitation chances. Amplitude of the trough itself and the presence of embedded shortwaves could also affect storm totals. Cold air advection as the trough moves in will send snow levels to around 8500 feet, meaning the higher peaks could receive a few inches of snow. Gusty northerly winds pick up on Sunday and Monday as the system exits, especially in the Colorado River Valley. Temperatures will be around 10 degrees below normal over the weekend and early next week.

Aviation

For Harry Reid: For the 06Z Forecast Package: Light and diurnal winds expected through the TAF period, with afternoon breezes generally around 8 kts. Can't rule out an occasional gust to 15 kts in the afternoon, with southeast being the favored direction. SCT-BKN aoa 25 kft increase through the overnight period and will continue through Wednesday.

For the rest of southern Nevada, northwest Arizona and southeast California: For the 06Z Forecast Package: Winds will be generally light and diurnal through the TAF period, with occasional gusts of 15 to 20 kts from the south-southeast at the Las Vegas Valley, Colorado River Valley, and Owens Valley TAF sites. KDAG will remain generally light from the east through the day on Wednesday. SCT-BKN aoa 25 kft will increase through the overnight period and will continue through Wednesday.

Spotter information statement

Spotters are encouraged to report any significant weather or impacts according to standard operating procedures.