Area Forecast Discussion

KEY MESSAGES

* Dry and seasonable weather conditions through at least Wednesday.

* Precipitation chances and cooler temperatures will return to the region later this week, continuing through the weekend.

DISCUSSION

through Sunday.

Relatively zonal flow aloft will allow dry conditions and seasonable temperatures to continue through the middle of the week. A few shortwaves will move through the Pacific Northwest today and tomorrow, resulting in southerly breezes across the southern Great Basin this afternoon. Southerly-to-southwesterly breezes will pick up across the area on Tuesday, with peak wind gusts in the 15 to 25 mph range tomorrow afternoon. Seasonable temperatures will continue through the middle of the week, with temperatures topping our right around normal for the next few days.

This quiet start to the week will give way to unsettled weather with the pattern becoming more active later this week as persistent troughing sets up over the West Coast. On Thursday and Friday moisture will begin to push up the Colorado River Valley and into adjacent counties, as Tropical Storm Vance moves into the Gulf of California, causing moisture to "surge" up the gulf. This will result in low-to-moderate (20 to 50%) chances of precipitation in northwestern Arizona, southeastern Nevada, and the Colorado River Valley on Friday as a shortwave moves through the area. The aforementioned troughing will result in southwesterly flow aloft, which will help draw a plume of moisture from the tropics towards the coast of Southern California/the Baja Peninsula as we head into the weekend. The exact trajectory of this moisture remains uncertain, resulting in low confidence regarding precipitation timing and amounts this weekend. The GFS ensemble mean favors a solution where the moisture plume stays further south, which would limit precipitation to the southernmost portions of our forecast area. Meanwhile, the ECMWF ensemble mean solution brings the moisture slightly further north, resulting in more widespread precipitation chances. In addition to uncertainty regarding the trajectory of this moisture, there is uncertainty regarding the magnitude of the moisture, which will directly impact precipitation totals. To complicate matters further, a shortwave will accompany this moisture plume, with interensemble discrepancies regarding the strength of this shortwave resulting in even more forecast uncertainty. All of this to say, this weekend's forecast is shaping up to be unsettled and wet, so make sure to follow along to stay informed.

AVIATION...For Harry Reid...For the 00Z Forecast Package

Winds through a majority of the forecast period will remain light and follow typical daily directional patterns. Tuesday early afternoon, winds will veer to the south-southwest, increasing to around 10KT, with an uptick in winds to around 12KT with gusts to around 20KT at the end of the forecast period. VFR conditions will continue with no operationally significant cloud cover anticipated.

For the rest of southern Nevada, northwest Arizona and southeast California...For the 00Z Forecast Package...Winds will remain between 5-10KT and follow typical daily directional patterns the next 24 hours. The only exception will be across the western Mojave Desert/KDAG, where winds generally remain westerly with some variability, mainly this evening. Otherwise, VFR conditions continue with no operationally significant cloud cover anticipated.

SPOTTER INFORMATION STATEMENT

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