Area Forecast Discussion
Issued by NWS Salt Lake City, UT
Issued by NWS Salt Lake City, UT
422 FXUS65 KSLC 111011 AFDSLC Area Forecast Discussion National Weather Service Salt Lake City UT 411 AM MDT Thu Jun 11 2026 .KEY MESSAGES, Issued 1033 AM MDT Wed Jun 10 2026... - Strong winds will accompany a dry cold front as it progresses southward through southern Utah during the overnight hours, especially through Black Ridge Canyon between Cedar City and St. George. - Temperatures will steadily warm Friday and Saturday, reaching around 5-10F above seasonal normals, increasing again from Monday forward and reaching 10-15 degrees above normal by Wednesday. - Increasing moisture over southern Utah will bring a few afternoon showers and thunderstorms over the higher terrain with the potential for isolated dry lightning Saturday and Sunday. Increasing winds Sunday into Monday will also increase the fire danger over southern Utah. && .DISCUSSION, Issued 1039 PM MDT Wed Jun 10 2026... A dry cold front will continue its progression through Utah during the overnight hours, bringing a period of stronger northerly winds as it progresses southward. Already, wind gusts of up to 35-40 mph have been observed across northern Utah as the boundary moved overhead. Similar wind gusts can be expected across central and southern Utah, especially along and west of the I-15 corridor, through the overnight hours. Channeling of winds through terrain constrictions between Cedar City and St. George are likely to cause winds to increase significantly, with peak gusts expected between 50 to 55 mph along the I-15 corridor from Kanarraville to Toquerville (and farther south into Hurricane). As of the latest suite of hi-res model guidance, there is around a 10% chance of winds exceeding 60 mph. Given the high probability of wind gusts in excess of 45 mph through this area (90% chance), a Wind Advisory for lower Washington County will go into effect from 3AM through 9AM. After 9AM, these strong gap winds will decrease as the effects of thermal mixing allow for less constriction of winds. With a cooler air mass in place across the region, temperatures across much of the forecast area will top out around 5-7 degrees below climatological average. The exception to this will be lower Washington County, where high temperatures will see very little change and top out in the low 100s. Thursday will also feature a nice relief from strong winds across Utah and southwest Wyoming as overhead winds weaken and conditions stabilize. A warm southerly to westerly return flow is expected to spread over the area on Friday, allowing for a significant jump in temperatures (particularly for northern Utah). High temperatures will return to above normal levels on Friday, with slight moderation by Sunday, and another warming trend being introduced from Monday forward as high pressure strengthens over the Great Basin region. As high temperatures reach upwards of 10 degrees above normal (pushing 93-95 degrees on the Wasatch Front and 105 in St. George by Tuesday/ Wednesday), risk of heat related illness will greatly increase. In fact, there is upwards of a 90% chance of HeatRisk reaching the "moderate" category (greatly affecting those sensitive to heat and those without access to adequate cooling/ hydration) and around a 15-20% chance of reaching the "Major" category (affecting a majority of the population). Will continue to monitor this potential as we head through the week. Lastly, this evening`s model guidance has shown a notable increase in potential for increased moisture content to push into southern Utah over the upcoming weekend. While it`s not quite what we`d describe as "monsoonal moisture", precipitable water (measure of total atmospheric water content) values (per ensemble output) will be pushing upwards of 200-215 percent of normal. With this increase in moisture over southern Utah, anticipate increased chances for afternoon shower and thunderstorm develop, especially over significant terrain features and adjacent valley areas. Given the low moisture content in the sub-cloud environment, a widespread threat of flash flooding is not expected. However, at least an isolated threat of flash flooding should be anticipated with the thunderstorm potential over slot canyons, dry washes, and recent burn scars. && .AVIATION, Issued 933 PM MDT Wed Jun 10 2026... KSLC, Issued 933 PM MDT Wed Jun 10 2026... VFR conditions prevail at the terminal through the TAF period under clear skies. Gusty northwesterly post-frontal winds taper off between 04-05z, becoming lighter overnight. There is potential for winds to become more variable between ~13-16z this morning as a drainage winds compete with prevailing northwest flow, but otherwise generally light northwest winds continue. .REST OF UTAH AND SOUTHWEST WYOMING...VFR conditions prevail for all regional terminals under clear skies across the airspace. A dry cold front will continue to move south across the airspace through early Thursday morning. Gusty north to northwesterly flow will accompany the frontal passage, with gusts 20-30 kts expected for most regional terminals across central and southern Utah. Otherwise, lighter winds prevail through the remainder of Thursday except KSGU, where canyon gap winds may keep gusts elevated into the late morning. && .FIRE WEATHER...A dry cold front will wash out across southern Utah as the trough associated with it shifts east of the region. Temperatures will cool behind the front Thursday, but daytime highs areawide will then return to around 5 to 10 degrees above normal Friday onward. Ridging will increase influence across the region during this time, allowing daytime winds and gusts to be much more modest than previous days. Conditions will remain quite dry with humidity values in the teens to single digits alongside poor overnight recoveries, supporting continued elevated to locally critical fire weather conditions where winds do increase sufficiently. There will be a brief minor incursion of moisture to southern Utah over the weekend. This should result in some isolated daytime convective development, particularly across the higher terrain. Wetting rain chances look fairly minimal, but activity that does develop will be capable of producing lightning and gusty erratic outflow winds. Moisture then once again decreases into next week, with little to no precipitation chances currently noted. && .SLC WATCHES/WARNINGS/ADVISORIES... UT...Wind Advisory until 9 AM MDT this morning for UTZ123. WY...None. && $$ PUBLIC...Webber AVIATION...Whitlam FIRE WEATHER...Warthen For more information from NOAA`s National Weather Service visit... http://weather.gov/saltlakecity