textproduct: Salt Lake City

DISCUSSION

Generally westerly flow remains across the region this evening. A few high-based showers have developed near the Utah/Nevada border, however given lack of instability across Utah, have generally remained near the border with little progress further east. Smoke from local fires including the Hastings, Bonneville, Iron and Sawmill fires as well as fires in Nevada and Arizona will continue to impact Utah. Low-level smoke is most likely in valley locations adjacent to the above fires through Monday.

As high pressure remains in place across the 4-Corners states, temperatures will warm to around 5 to 10 degrees above normal. These hot conditions may impact those most prone to heat including the elderly as well as unsheltered populations and those without adequate cooling and hydration. Please remember to properly hydrate during outdoor activities, including carrying enough water on hikes. Current temperature forecasts fall short of heat advisory criteria, so no advisories will be issued with this package.

By Wednesday, the majority of ensemble members bring PWs around 95 to 98 percent of normal into southern Utah as moisture advection from the eastern Pacific/Baja streams northward ahead of the next Pacific trough. This moisture surge looks to remain largely aloft, with mid-level moisture advection sufficient to bring the threat of high-based convection to portions of southern Utah as early as Wednesday afternoon.

Mid-level moisture may shift far enough north by Thursday to impact portions of northern and central Utah, though, again, convection looks to remain mainly high-based with the ever present threat of microburst winds in excess of 50 mph.

The previously mentioned trough will shift into the Pacific Northwest by Friday, bringing a dry, hot and windy pattern into Utah...with an increasing probability of widespread critical fire weather conditions across nearly all zones with critical fuels Friday and Saturday.

In reality, there is a very low chance of precipitation for most locations over the next 7 days outside of briefly heavy rain under a stronger thunderstorm Wednesday or Thursday.

AVIATION

Light variable or southeasterly winds will persist through the night into Monday morning, becoming northwesterly after 17-18z. VFR conditions will likely prevail, however smoke from nearby wildfires could produce brief periods of MVFR VIS, particularly around sunrise/sunset.

REST OF UTAH AND SOUTHWEST WYOMING...Typical diurnal winds can be expected across much of the area through Monday. Although many sites will experience VFR conditions, wildfire smoke could result in reductions in slantwise VIS, particularly around sunrise/sunset.

FIRE WEATHER

High pressure will strengthen across the area during the first half of the week, resulting in a return to hot and very dry conditions by Tuesday. Daytime temperatures Tuesday and Wednesday will run 5-10 degrees above normal with very low daytime RH and marginal to poor overnight recovery. With this strengthening high, general winds will remain fairly light from the west to southwest. The exception will be portions of south central and east central Utah, where gusts may locally exceed 25 mph and result in pockets of locally critical fire weather conditions in zones 482, 489 and 498

High based moisture will begin to increase Wednesday afternoon across southern and potentially central Utah, bringing a chance for high based showers and dry thunderstorms. This moisture looks to increase on Thursday, bringing a mixture of wet and dry thunderstorms. A dry and strengthening southwesterly flow will follow Friday into Saturday as this ridge breaks down, which will likely bring a return to critical fire weather conditions across much of the area.

SLC WATCHES/WARNINGS/ADVISORIES

UT...None. WY...None.