Remnants of Tropical Storm Vance are forecast to bring rain to the Bountiful-Farmington area over Halloween weekend, with flooding possible Sunday.

The storm system will push scattered showers across Utah on Saturday, Oct. 31, followed by widespread rain on Sunday, Nov. 1, according to ABC4 Utah meteorologist Noah Price. Soils are already saturated from a previous round of tropical moisture, and Price wrote that additional rain Friday and Saturday will leave nowhere for the excess water to go.

A large trough off the Pacific Northwest coast will funnel moisture into the Great Basin starting Friday, Oct. 30, with isolated showers across most of the state. At the same time, leftover moisture from Tropical Storm Vance will be drawn into the system, Price reported.

Halloween night

Saturday's showers are forecast to be on-and-off, so trick-or-treaters may find dry windows between rounds of rain. Evening temperatures are expected in the 40s and 50s across Northern Utah. Price recommended dressing warmly and keeping rain gear handy.

Sunday flooding concern

The bigger concern comes Sunday. That is when the bulk of Vance's remnants move in, bringing widespread rain statewide.

"Flooding could be a major threat for low-lying areas on Sunday," Price wrote.

As of Tuesday, Oct. 27, the Weather Prediction Center (WPC) had placed Southern Utah under a "Marginal" flood threat, rated level 1 out of 4. Price noted the WPC does not issue that designation four days in advance unless confidence is solid, suggesting the threat could be upgraded as the storm draws closer.

Cooler temps, mountain snow

Temperatures Sunday and Monday, Nov. 2, are forecast to drop to the upper 40s and low 50s for highs, with overnight lows in the 30s and 40s. Snow levels may fall to about 7,000 feet, which would include higher mountain valleys like Park City. Areas below 8,500 feet would see more of a rain-snow mix, according to Price.

Mountains could see a few inches to roughly a foot of snow, though Price cautioned the forecast is still far out.

Wet weather is expected to ease by Tuesday, Nov. 3, in time for Election Day.