textproduct: Salt Lake City

KEY MESSAGES

- Daily chances for showers and thunderstorms across most of Utah and southwest Wyoming continue through this upcoming week as monsoonal moisture remains in place.

- Flash flooding remains a concern across the region through at least Thursday, especially across southern Utah on Tuesday and northern Utah and southwest Wyoming on Wednesday.

- Hot daytime temperatures and warm overnight lows will lead to widespread Major HeatRisk across much of the Wasatch Front and northwest Utah on Monday.

DISCUSSION

Showers are once again waning tonight across the region outside of some lingering convection across southeast Utah that should taper off just after midnight. A typical monsoonal pattern remains in place, defined by a broad ridge overhead. The ridge is expected to amplify overhead on Monday, with southeasterly flow aloft increasing across the region as a result. While scattered showers develop once again Monday afternoon as monsoon moisture remains in place, coverage will be a bit more isolated with stronger steering flow aloft. As such, the flash flood risk is lower across the region tomorrow, though a Marginal Risk (level 1/4) for excessive rainfall across most of Utah and southwest Wyoming still exists, given flash flooding remains a threat if a strong cell develops over sensitive terrain.

The amplifying ridge on Monday will also yield a slight bump in temperatures, with highs for northern Utah valleys breaking the century mark once again. Given warm overnight lows Monday morning, this will exacerbate heat impacts and raise the risk for heat illnesses mainly across the Wasatch Front and Great Salt Lake Desert.

The flash flood risk rises again Tuesday through Wednesday as the ridge flattens in response to a trough moving into the Pacific Northwest, bringing an additional surge of monsoonal moisture. Main concern for Tuesday exists across southern Utah, while the threat shifts across northern Utah and southwest Wyoming on Wednesday as monsoonal moisture spreads northward. While moisture lingers through the remainder of the week across the region, the broad ridge begins to slide west through the latter half of the week, introducing drier, more stable conditions which will limit the potential for the daily convection chances to continue into the weekend.

AVIATION

KSLC...There is a 10% chance of convection before 02Z Monday. NW winds will otherwise shift SE around 04Z, with lingering high level VFR cloud cover. Winds are then favored to shift back NW between 17- 19Z Monday. There is then approximately a 15-25% chance of showers or thunderstorms impacting the terminal, generally mid to late afternoon Monday. Any such activity will bring potential for lightning, brief reduction to CIGS/VIS, and gusty erratic outflow winds.

REST OF UTAH AND SOUTHWEST WYOMING...Like previous days anticipate convection across the region to wane through 03Z or so, with remnant outflows bringing potential for gusty and erratic wind gusts. Otherwise, anticipate some lingering VFR cloud cover, thickest near where convective coverage was highest (southern and central Utah), with winds favored to settle out to a diurnally normal to light and variable direction overnight. Monday will then will also see a similar progression to previous days with afternoon showers/thunderstorms developing, most widespread across southern to central Utah. This will bring potential for lightning, periods of heavy rain (and briefly reduced CIGS/VIS to MVFR or so), and gusty erratic outflow winds.

FIRE WEATHER

Monsoonal moisture remains across UT increasing humidities while raising chances for showers and thunderstorms across the state moderating fire weather conditions overall. Chances for showers and thunderstorms remain elevated across central and southern UT, and the Uintas ranging from 50-80%. A wetting rain remains favored this afternoon across each mentioned location. Expect showers and thunderstorms to develop along higher terrain parallel to I-15 each afternoon over the next several days around 1200-1400 with gusty outflow winds, heavy rainfall, and lightning. Winds will generally remain light terrain driven / diurnal over the next several days.

SLC WATCHES/WARNINGS/ADVISORIES

UT...Heat Advisory from noon Monday to midnight MDT Monday night for UTZ101>105.

Flood Watch until midnight MDT Sunday night for UTZ122>128.

WY...None.