Area Forecast Discussion
Issued by NWS Las Vegas, NV
Issued by NWS Las Vegas, NV
953 FXUS65 KVEF 010311 AFDVEF Area Forecast Discussion National Weather Service Las Vegas NV 811 PM PDT Sun Jun 30 2024 .SYNOPSIS...Hot and breezy conditions will continue across most of the region today. Monsoonal moisture will move back into northwest Arizona today, bringing slight chances for thunderstorms in eastern Mohave County through the middle of the upcoming week. A strong ridge of high pressure will build Wednesday through the Independence Day weekend, with temperatures climbing to dangerous levels for several days. && .UPDATE...Winds continue to decrease this evening as the sun sets, thus the Red Flag Warning for Lincoln County has been allowed to expire at 8 PM. With today`s high and low temperatures pretty much locked in at this point, we can do a little number crunching to get June`s numbers for our climate sites. Long story short, it was a hot one. All 7 climate sites recorded a top-5 warmest June, with Las Vegas shattering its June records. Coming back to the forecast, we`ll be monitoring the potential for some showers/storms creeping into southern Mohave County tonight. Should convection reach this area, the main concerns would be isolated heavy downpours, but the chance of flash flooding is less than 10%. Rain chances through mid- week will be confined to Mohave County as the edge of monsoonal moisture noses in. Otherwise, our forecast area remains dry and hot, with temperatures running 3-6 degrees above normal. During the 2nd half of the week, heat becomes more excessive as high pressure builds. Many locations will likely be flirting with daily records, and it`s possible a few all-time highs could be challenged. Stay cool out there. && .SHORT TERM...tonight and Through Tuesday Night. Will need to watch the moisture pool that is situated over the Sonoran Desert this afternoon and how it may influence the weather in southern Mohave County tonight. The latest HREF and hi-res models do develop showers and thunderstorms that might rotate into southeast portions of Mohave County tonight. This is when HREF shows 30%-40% probabilities for SB CAPE over 500J/kg and a brief increase of PWATs to 1.0-1.5 inches. The probability for dewpoints over 60F also increases to 80%-90% this evening and tonight in areas south of I-40 in Mohave County. Based on this change in the atmosphere since the previous forecast and ensemble trends, ensured there was a mention of precipitation tonight through the area. Focused on the far southeast corner of Mohave County, will monitor trends and model output to see if precipitation chances need to be brought further west tonight. Even with all this, chances will be low (30% or less) and impacts would be limited. Lightning is noted on HRRR models tonight and with some midlevel instability seen on model soundings in the area, lightning will be the main threat. Gusty outflow winds and brief heavy rain will also be possible. Will need to watch for a potential outflow winds pushing in from convection that develops further south. A few hi-res wind models do show a south to southeast outflow moving through southern Mohave County this evening and tonight, but no impactful winds were noted. Across the rest of the region, it will remain dry. Breezy winds this evening will subside tonight but should pick up again Monday afternoon. Winds Monday afternoon will be slightly lower than today;s winds as the upper level system that brought breezy winds to the area lifts north. Most of the region will remain dry through Tuesday night. There is a low chance for isolated showers and thunderstorms in far eastern Mohave County at the moisture that may push in tonight lingers over that area. PWATs start to decrease Monday afternoon through so any precipitation will be very isolated and impacts will be limited. By TUesday, PWATs drop enough that precipitation is not expected across the region including Mohave County. Temperatures will begin an upward climb on Tuesday as high pressure builds back into the region as the shortwave lifts away. Monday`s high temperatures will be similar to today, then on Tuesday it will warm a few degrees and a moderate heatrisk is expected in most locations outside of the Southern Great Basin. Anyone with outdoor plans or who are sensitive to the heat should be aware of the heat on Tuesday, drink extra water and take breaks in cooler areas. .LONG TERM...Wednesday through Saturday. The extended outlook continues to point to an excessively hot period setting up for a large portion of our area midweek and beyond. Wednesday looks like the start of an extended period of dangerously hot conditions with multiple days of near record or record heat forecast across the Western Mojave Desert including the Barstow area, across much of Inyo and central and southern Nye counties including Death Valley National Park, Pahrump, and Beatty, and in the Las Vegas Valley. Major to extreme Heat Risk is forecast in these areas through the period where temperatures could approach, tie, or even break daily heat records. Probably the biggest forecast challenge will be in deciphering the daily fluctuation in Heat Risk levels across areas generally south of the I-15 and how this information will be best relayed to emergency management officials and to the public. Moderate to major Heat Risk is indicated throughout the period with Friday standing out as the peak day featuring widespread high Heat Risk. This magnitude of heat is dangerous to everyone and proper safety precautions are recommended including limiting time outdoors and staying hydrated. && .AVIATION...For Harry Reid...South to southwest breezes are expected through the afternoon, with gusts over 20KT expected and a moderate probability (60% chance) for gusts over 25KT between 20Z-02Z today. Winds will decrease this evening with gusts ending around 03Z-04z. Moderate confidence in the overnight wind speed forecast. Will be southwest much of the night before transitions to the south Monday early morning, however its a 50% chance for winds to remain elevated at 8-10KT through the night. Kept the elevated winds in through the night however they may be lighter overnight, especially after 09Z.1031 High confidence that winds increase again Monday morning after sunrise with the probability for wind speeds over 10KT jumping back to 80% or higher at 15Z. South to southwesterly breezes are expected again Monday afternoon with wind speeds and gusts slightly lower than today`s winds. No significant clouds or weather are expected through the forecast period. 100F temperatures are likely 19Z to 02Z today and Monday. For the rest of southern Nevada, northwest Arizona and southeast California...Souther to southwest winds will gust 20-25KT across much of the region this afternoon. Winds at KDAG will favor a more westerly direction but like likely (80% chance) still see gusts over 20KT after 21Z. KBIH will follow typical diurnal directional patterns through much of the afternoon until a west push moves in around 00Z. Gusts up to 20KT are possible (60% chance) with the west winds at KBIH. Winds will decrease this evening and should follow typical wind patterns overnight. Elevated north to northeast winds are possible at KBIH 03Z-06Z before typical northwest winds at 8KT or less set up for the overnight period. Will need to watch for outflows coming out of south-central Arizona that could push through southern Mohave County into KEED and KIFP after 09Z, which would turn winds southeast and bring gusts to around 20KT. No significant clouds or weather are expected through the forecast period. && .SPOTTER INFORMATION STATEMENT...Spotters are encouraged to report any significant weather or impacts according to standard operating procedures. && $$ UPDATE...Woods SHORT TERM...Nickerson LONG TERM...Salmen AVIATION...Nickerson For more forecast information...see us on our webpage: https://weather.gov/lasvegas or follow us on Facebook and Twitter