295 FXUS65 KVEF 151025 AFDVEF Area Forecast Discussion National Weather Service Las Vegas NV 325 AM PDT Mon Oct 15 2018 .SYNOPSIS...Gusty north winds will persist today and Tuesday, especially within the lower Colorado River Valley and adjacent eastern San Bernardino County. The first freeze of the season will occur in parts of the Owens Valley and southern Great Basin this morning. Gradually moderating temperatures are expected the rest of the week with isolated showers or thunderstorms possible over parts of Mohave County Tuesday and Wednesday. && .SHORT TERM...through Monday night. Gusty winds have been noted across portions of the area this morning with the strongest winds occurring along the Colorado River Valley along with eastern portions of San Bernardino County. These areas are all cover with the wind advisory which is in effect. There have also been some isolated wind gusts over 50 mph across Lincoln County, but these areas are rather remote and the more impactful areas has remained below 40 mph. Elected not to add them into the advisory. Over the next 12-24 hours the models are forecasting a closed low to develop over SW Arizona which then remains nearly stationary through mid week. Moisture that is currently situated over Mexico and Texas is forecast to get drawn up into the low and bring the potential of showers to portions of western Arizona and possibly far southeast San Bernardino County Tuesday and Wednesday. There is not a lot of instability associated with the low, but there could be just enough dynamics to help kick off a few showers. Any rain that does fall should remain fairly light with generally less than a tenth of an inch. Any wiggle with the low could spread precipitation further west, but have left much of southern Nevada out of the precipitation. Temperatures are expected to be about 10 degrees below normal today and Tuesday as cooler air filters into the area from the north. .LONG TERM...Wednesday through Sunday. The stubborn upper low that will be parked over the southwest US over the next week will...still be there come Wednesday. This upper low appears to tap into a band of moisture that is currently extending from south of the tip of Baja California to across Texas, which is bringing them the significant rainfall they are experiencing. This should produce some isolated to scattered shower potential for Mohave county Wednesday, possibly as far west as the Colorado River (depending on the exact location of the upper low). The key difference in the long range guidance tonight vs this time yesterday is subtle differences in the evolution of the closed low Thursday/Friday and into the weekend. A more progressive shortwave out of Canada will serve to cut off the low center from the overall flow pattern and trap it under a developing ridge axis over the western CONUS by the weekend. As the remnant low shifts westward towards southern California and eventually off-shore, it should again pull moisture northward and into the region Saturday night and Sunday. Went ahead and raised PoPs for this time frame in collaboration with neighbors. QPF values still do not look too substantial at this point per WPC guidance. Temperature-wise, gradual warming through the week is expected, with highs in the Las Vegas Valley reaching the low 80s by the weekend. Looking at the CPC 8-14 day temperature outlook, a fairly strong signal for above average temperatures looks to be on the horizon as the next stout upper low approaches the Pacific Northwest early next week. && .AVIATION...For McCarran...Gusty north to northeast winds will persist through today with speeds generally between 12-22 kts. Some gusts up to 25 kts will be possible late morning and early afternoon. Mostly clear skies expected through the day. For the rest of southern Nevada, northwest Arizona and southeast California...Gusty north to northeast winds will persist through much of the day. Strongest winds will be along the Colorado River Valley. TAF sites KEED and KIFP will have the higher gusts, with around 40 knots possible. Skies will remain mostly clear, with the exception of some 10-12k foot clouds across portions of Mohave County this afternoon south and east of IGM. && .SPOTTER INFORMATION STATEMENT...Spotters are encouraged to report any significant weather or impacts according to standard operating procedures. && $$ SHORT TERM/AVIATION...Gorelow LONG TERM...TB3 For more forecast information...see us on our webpage: http://weather.gov/lasvegas or follow us on Facebook and Twitter |