Area Forecast Discussion
Issued by NWS Las Vegas, NV
Issued by NWS Las Vegas, NV
778 FXUS65 KVEF 312055 AFDVEF Area Forecast Discussion National Weather Service Las Vegas NV 155 PM PDT Fri May 31 2024 .SYNOPSIS...Gusty south-southwest winds will pick up across the region on Saturday. Otherwise, expect above-average temperatures and dry conditions for the first full week of Meteorological Summer. && .DISCUSSION...Today through next Friday. Today, there is a 55% chance of Las Vegas reaching 104 degrees. This is noteworthy, because this is the record high temperature for May 31st and has occurred 4 times (2015, 2002, 1997, 1977). Records at other climate sites are unlikely today, as this 104 record is low- hanging fruit (May 30th record is 106 and June 1st record is 107). As of 1:30pm, the high observed so far at Harry Reid Airport is 101 degrees. As mentioned in the previous forecast discussion, a broad longwave trough over the western United States will escort a series of perturbations in the flow across the Great Basin, resulting in breezy afternoons through the week. Saturday`s winds look to be the strongest of the week as a shortwave trough rides along the flow through the southern Great Basin. This will increase surface pressure gradients and result in gusty south-southwest winds across the forecast area. Speeds will range from 30 to 40 mph in the western Mojave Desert / western San Bernardino County... and from 20 to 30 mph elsewhere. With dry conditions expected, this could result in increased fire weather concerns. However, with the lack of cured fuels, no fire-related headline has been issued at this time. Heights rise through the work week as a high pressure center sets up over the Intermountain West. Temperatures will rise to around 10 degrees above seasonal averages Wednesday and Thursday. HeatRisk increases into the Major category on Wednesday and Thursday for desert valleys, meaning anyone without adequate cooling or hydration will be at risk for heat-related impacts such as heat exhaustion or heat stroke. June 6th is the record earliest that Las Vegas has observed 110. This Thursday, June 6th, there is a 43% chance of reaching 110. A weak closed low will move into Baja California late-week, which will allow moisture to usher up into the Mojave Desert by the weekend. There is too much uncertainty at this moment to determine how much moisture, but all it will take is some cloud cover to drop temperatures back toward seasonal averages. && .AVIATION...For Harry Reid...Winds could be erratic for much of the afternoon before finally settling into a southerly direction with gusts 15 to 20 knots around 00Z. Gusts will end after sunset. Any period of erratic winds Saturday should be shorter, and winds should come around to the south earlier in the day, closer to 19Z. The risk of erratic winds is likely to return on Sunday. No operationally significant clouds or weather expected through the weekend. For the rest of southern Nevada, northwest Arizona and southeast California...Wind gusts around 20 knots or less are expected this afternoon, primarily from a southwesterly direction. Stronger southwesterly winds are expected Saturday, with gusts generally around 25 knots, but stronger in areas of favored terrain. Winds should relax again Sunday, with gusts around 20 knots or less. No operationally significant clouds or weather expected through the weekend. && .FIRE WEATHER...Afternoon minimum relative humidities will be in the single- digits to low-teens each afternoon this weekend. Moisture will modestly increase across the southern Great Basin and southeastern California Monday and Tuesday, though minimum RH will remain below 15%. Conditions dry out once again midweek. Meanwhile, expect gusty south-southwest winds on Saturday between 20 and 30 mph. Otherwise, breezy afternoons between 10 and 20 mph expected through the week. && .SPOTTER INFORMATION STATEMENT...Spotters are encouraged to report any significant weather or impacts according to standard operating procedures. && $$ DISCUSSION...Varian AVIATION...Morgan For more forecast information...see us on our webpage: https://weather.gov/lasvegas or follow us on Facebook and Twitter