Las Vegas (VEF) — the National Weather Service forecast in plain English · Plaincast

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Well above normal temperatures continue Friday, then temperatures drop 5-10 degrees this weekend.

Isolated convection possible in Northern Mojave and Lincoln Counties Friday.

Breezy south-southwesterly wind gusts expected across the region Friday through the weekend. With reduced humidities leading to fire weather concerns.

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While Thursday will likely have been the hottest day of the week, well above normal temperatures continue Friday before temperatures cool down this weekend by 5-10 degrees. A hot airmass is currently in place across the region with 850mb temperature anomalies well above normal for this time of year, supporting highs at or above 100 in desert valleys and in the CRV. The strong ridge which built in overhead earlier in the week is showing signs of breaking down as a trough pushes into the PNW. By Friday, the 500mb high shifts southeast into AZ, then continues eastward through the weekend becoming centered over Southern New Mexico while the PNW trough pushes inland. Influence from the incoming trough, lowering upper heights, and strong subsidence shifting out of the region should all result in cooling surface temperatures across the Mojave Desert and Great Basin. Low and mid level temperature anomalies still remain above normal for this time of year, so still expect daily highs and lows above normal as well. but not at the levels seen this past week. Lingering monsoonal moisture will also help keep nighttime lows elevated the next few days with lows in the 80s likely in desert valleys, preventing much relief from the heat. By next week, a persistent troughing pattern looks to set up over the west coast, keeping southwesterly flow aloft locally and preventing strong ridging from developing overhead. Medium to long range guidance keeps low and mid level temperature anomalies and upper level height anomalies near to slightly above normal for this time of year into next week. This raises confidence that temperatures will continue to run above normal by a few degrees for both highs and lows into the extended period; however with Heat Risk remaining low to moderate, not expecting dangerous heat conditions to return in this pattern. Highs generally in the 90s with lows in the 70s can be expected in desert valleys, the CRV, and death valley in the extended while cooler temperatures are likely at higher elevations.

As mentioned above, lingering monsoonal moisture still remains in place for portions of the region just ahead of the trough. Hi-res guidance shows the potential for scattered convection in portions of Lincoln and Mohave counties Friday as a weak disturbance passes through. Added chance wording in the forecast to account for this threat, but not expecting much impacts from anything that does develop. Brief periods of heavy rain, lightning, and gusty winds possible with any storm that does develop.

The aforementioned trough pushing into the western US will also increase southwest winds across the region. Guidance continues to show a 40 knot mid level jet streak developing overhead Saturday into Sunday. Mixing into this area of stronger winds will result in widespread gusts mixing down to the surface 30-35 mph. There could also be some gusty southerly winds impacting Lake Mohave and Lake Havasu this weekend, which could impact boaters with winds and waves. Since the low to mid level jet ramps up during the overnight hours Friday and Saturday night, the strongest winds in the region may occur in wind prone areas of San Bernardino county with the nightly westerly push and also at higher elevations across the region. Looking at today's Ensembles and the blend-of-models forecast probs, all guidance has kept the threat relatively low for gusts over 40mph. While it does still look breezy with frequent gusts over 30mph, latest trends lower confidence in frequent gusts over 40 mph and the possibility of needing a wind advisory. Still will monitor forecast trends through the week and will update the forecast accordingly.

This coupled with very dry conditions has increase fire weather concerns, with a Fire Weather Watch in effect for Nye, Esmeralda, and portions of Lincoln and Clark counties for Saturday. Winds look to reduce for Sunday but remain breezy. Longer term models are starting to favor breezy winds peaking around 25 mph each afternoon into the first half of next week.