Area Forecast Discussion
Issued by NWS Las Vegas, NV
Issued by NWS Las Vegas, NV
429 FXUS65 KVEF 101647 AFDVEF Area Forecast Discussion National Weather Service Las Vegas NV 946 AM PDT Wed Jul 10 2024 .SYNOPSIS...Historic heat continues through the work week, keeping HeatRisk in the Major to Extreme categories for most locations. Monsoonal moisture returns this weekend, bring some relief from the heat and increasing rain chances. && .UPDATE...Las Vegas only managed to get down to 94 degrees this morning, 1 degree off our all-time record warm low. As I`m typing this, we are already back up to 106 degrees, placing us a degree or two ahead of yesterday. With the 500mb high firmly centered overhead, there is a very real chance we hit 120 this afternoon. The previous sentence would have sounded absurd a week ago, but given the past several days, it almost seems like no big deal now. But don`t be fooled, it is a big deal. This is pretty much undeniably the most intense heat wave our area has ever seen, and it will continue through Friday. By the weekend, moisture and rain chances increase, bringing some temperature relief that lasts into next week. && .SHORT TERM...through Friday. Very strong high pressure center will meander over southern Nevada the next couple days, ensuring a continuation of our historic heat wave through at least Friday. 500mb heights and 850mb temperatures generally plateau today and Thursday, so regional high temperatures may fluctuate a degree or two each afternoon but should remain pretty steady overall, continuing to flirt with or exceed daily and some all-time records. The high will begin to nudge east on Friday with very slight cooling (read 1-3 degrees) by Friday afternoon. Somewhat more notable cooling may creep into northwest Arizona and the lower Colorado River on the axis of some richer monsoonal moisture that will begin working in from the east over the weekend. Otherwise, dry conditions will persist aside from some very weak and high based virga showers across the highest terrain of the southern Great Basin during the late afternoon and evening - largely induced by the intense surface heating. Isolated showers and thunderstorms will return to Northwest Arizona by Friday evening with increasing moisture within a flow pattern that begins to trend more southeasterly. With this moisture encountering increasingly hot and dry conditions with westward extend, gusty outflow winds, dust, and a few instances of dry lightning will be the main concerns. .LONG TERM....Saturday through next Wednesday. Model ensembles continue to indicate the strong area of high pressure responsible for the long and extreme heat wave over our region will finally become centered around the Four Corners by Saturday. This is the typical monsoon pattern which results in southeast flow developing across Arizona and Nevada drawing moisture up from Mexico. Ensemble mean PWAT values ranging from 1.00" around Clark County to 1.50" in the lower Colorado River Valley are forecast Saturday into Sunday. This will lead to a general 30-50 percent chance of showers and thunderstorms, primarily over the higher terrain. This does not appear to be a deep push of moisture, but once in place, the moisture may remain somewhat entrenched through early next week. However, the majority of ensemble clusters indicate a broad weak trough bringing increasingly dry southwest flow across our region and the NBM has diminishing PoPs Tuesday into Wednesday. The typical monsoon hazards (flash flooding, gusty outflow winds, dust, & lightning) will all be in play Saturday through Monday. && .AVIATION...For Harry Reid...Diurnal winds with speeds of less than 10 knots are forecast this morning and early afternoon. Later in the afternoon, winds increase to 10 knots or greater and become gusty out of the west to southwest. Peak gusts of around 20 knots are possible. Gusts should decrease by the early morning hours and speeds fall to less than 10 knots, maintaining a southwesterly direction. FEW mid level clouds pass over the area through the day and tonight. Temperatures rise to above 100 degrees by around 16Z and fall to less than 100 degrees around 09Z. For the rest of southern Nevada, northwest Arizona and southeast California...Diurnal winds with speeds of less than 10 knots are expected at most locations this morning. However, gusty westerly to southwesterly winds develop at most terminals this afternoon and evening except for KIFP, decreasing again early tomorrow morning. Peak gusts should be around 20 knots or less. FEW mid level clouds pass over the area through the day and tonight. Highs today will be between 110 and 120 degrees. && .CLIMATE...Numerous climate locations have a forecast high temperature and/or forecast warm low temperature within 3 degrees of the daily record. The table below shows the daily record maximum temperature and the year the record was last set. An asterisk (*) denotes which records are in jeopardy (within 3 degrees of the forecast). MAX WED, JUL 10 THU, JUL 11 FRI, JUL 12 Record(Yr) Record(Yr) RECORD (Yr) Las Vegas 117(2021)* 116(1959)* 114(2003)* Bishop 111(2021)* 109(2021)* 108(2020)* Needles 122(2021)* 120(2020)* 124(1925) Daggett 118(2021)* 117(2021)* 115(2021)* Kingman 111(2021)* 110(1961)* 111(2020) Desert Rock 111(2021)* 114(2021)* 112(2021)* Death Valley 134(1913) 129(1913)* 130(1913)* The table below shows the daily record warm minimum temperature and the year the record was last set. An asterisk (*) denotes which records are in jeopardy (within 3 degrees of the forecast). WARM MIN WED, JUL 10 THU, JUL 11 FRIDAY, JUL 12 Record(Yr) Record(Yr) RECORD (Yr) Las Vegas 94(2021)* 91(2012)* 94(2020)* Bishop 71(1985) 70(2013) 69(1990)* Needles 98(2021) 96(2021) 96(2021) Daggett 88(2021) 90(2021) 87(2012)* Kingman 79(1913)* 81(2021)* 80(2021)* Desert Rock 82(2021)* 87(2021) 83(2023)* Death Valley 100(1927)* 105(1920) 107(2012) && .SPOTTER INFORMATION STATEMENT...Spotters are encouraged to report any significant weather or impacts according to standard operating procedures. && $$ UPDATE...Woods SHORT TERM...Outler LONG TERM...Adair AVIATION...Meltzer For more forecast information...see us on our webpage: https://weather.gov/lasvegas or follow us on Facebook and Twitter