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SALT LAKE CITY — September has already been one for the record books.
Salt Lake City's six hottest September days dating back to 1874 were set in the first week of the month, while a seventh day also matched the previous record of 100 degrees. Many new daily and all-time monthly heat records were also set in other parts of the state, as a part of a massive regional heat wave.
Then, as the record heat subsided last week, smoke from Western wildfires arrived with a cold front that swept across the state. The air quality across many communities in the state dipped to levels considered either unhealthy for sensitive groups or even unhealthy for anyone over the weekend and into Monday.
Now it's time for rain to take over as Utah's dominant weather pattern this week. The remnants of Hurricane Kay have reached the Southwest U.S. and now Utah, which will mix with a low-pressure trough coming from the West. Combined, the storms will deliver much-needed rain to the drought-stricken Beehive State but also the risk of possibly more flash floods through at least Thursday, according to the National Weather Service.
KSL meteorologist Matt Johnson points out that current models show the potential for as much as 2 inches of rain to fall across many parts of northern Utah this week — and possibly even more in the northern portion of the Wasatch Mountains.
Just what the doctor ordered! 🌧️— Matthew Johnson (@KSL_Matt) September 12, 2022
Tropical remnants from Kay will collide with a couple of cool fronts this week. This week's rain totals showing a bullseye right over northern Utah and the Wasatch! Over the next 7 days we could pick up .5-2.00"! #utwxpic.twitter.com/7Q451H6C44
It all starts with the remnants of Hurricane Kay, which have already provided some rain in southwest Utah. St. George, for example, received nearly a quarter of an inch of rain on Sunday, according to National Weather Service data. It also has resulted in a slew of flash flood watches across Arizona and Nevada.
Johnson said the system will continue to bring showers and storms to southwest Utah that have the ability to "pack a punch" on Monday. The weather service tweeted that flash floods are probable at Zion National Park and possible at a few other of Utah's outdoor wonders. The system will continue to move north toward other parts of the state on Tuesday.
"This southerly flow is also going to blow out some of that smoke, especially, by (Tuesday)," Johnson said.
⛈ An increased flash flood threat begins Monday across southern Utah, with an increasing threat across northern Utah and southwest Wyoming beginning Tuesday. Continue to monitor the forecast, and remember: turn around, don't drown! #utwx#wywxpic.twitter.com/1qezZDZNTG— NWS Salt Lake City (@NWSSaltLakeCity) September 11, 2022
Johnson adds that the remnants of the hurricane are also projected to "collide" with a couple of cold fronts as the week continues, which will boost precipitation totals, particularly in the northern half of Utah. This is why areas in northern Utah could receive multiple inches of rain throughout the week.
The current forecast shows the potential of rain to continue in the region through Friday, though most of Utah's rain is forecast between Monday and Thursday. There is also a chance for rain in parts of northern and eastern Utah Saturday afternoon and evening; however, the forecast calls for a majority of the state to dry out again this weekend.
Good morning! We're keeping a close eye on the remnants of Tropical Storm Kay off the California coast. Moisture from the system will move into S UT today before the remnants move across UT tonight through Tuesday, bringing the potential for heavy rain across the state. #utwxpic.twitter.com/ID9sDeBRWv— NWS Salt Lake City (@NWSSaltLakeCity) September 12, 2022
Temperatures will also return to seasonal normals as a result of yet another shift in the September weather. That includes overnight lows that are expected to dip into the 40s, 50s and 60s this week in different parts of the state.
"(It's) a different pattern coming our way — a very welcoming sight for us, here," Johnson said.
September typically provides about 1.16 inches statewide, based on the 30-year average collected by the National Centers for Environmental Information. If this week's forecast comes to fruition, it would be a major boost for Utah's 2022 water year as it comes to a close.
Salt Lake City is currently 2.41 inches below normal for this point in the water year, while Cedar City is 2.66 inches below normal, per weather service data. The entire state entered September with 10.73 inches of precipitation collected, which is about 1.75 inches below the 20th century normal for the first 11 months of the water year, notes data from the National Centers for Environmental Information.
These precipitation deficits, combined with deficits over the past few years, are why about 57% of Utah remains in at least extreme drought, according to the U.S. Drought Monitor. It reached as high as 84% over the summer before monsoonal moisture lowered the percentage of extreme drought. All parts of the state remain in at least a moderate drought.
The water year wraps up at the end of this month.
Full seven-day forecasts for areas across Utah can be found online at the KSL Weather Center.