textproduct: Salt Lake City

KEY MESSAGES

- A strong cold front will continue a gradual southeastward progression into Sunday. Much cooler temperatures will follow the front, with daytime highs Sunday running 20 to 25 degrees below normal over northern Utah and 10 to 15 degrees below normal over central and southwest Utah.

- A warming trend is expected through midweek, with temperatures returning to near normal by Thursday. Deepening southwest flow will result in increasingly mild, dry, and breezy conditions, with areas of critical fire weather conditions redeveloping in turn by Thursday.

DISCUSSION

After an active day, evening synoptic analysis shows an abnormally strong trough continuing to deepen into the Great Basin, gradually pushing a correspondingly strong cold frontal boundary southward as it does so. With waning instability moving into the overnight hours, activity has continued to trend weaker. A low end shower chance will remain possible along the convergent zone of the front, as well as within the core of the broad trough as lobes of embedded energy continue to ripple through.

With the slow deepening and movement of the trough, the southeastward frontal progression will also remain slow. Saturday night into early Sunday the front looks to only progress as far as a line from about southwest Utah up through northwest Colorado. A much colder airmass will continue to sink in behind the front, resulting in unseasonably cool temperatures across the northwestern half of Utah and southwest Wyoming, on the order of 10 to 25 degrees below seasonal normal. Forecast highs across the Wasatch Front for example look to be closer to early October rather than late June. With lingering moisture and embedded energy within the base of the trough, northern Utah and southwest Wyoming will also still see some isolated to scattered shower activity (~10-40% chance). Given the cold air, some of the high northern elevations above 8500-9000 feet or so will actually have potential to see some snow showers.

Ahead of the front however temperatures will remain a bit closer to normal, and deep southwesterly flow in combination with the tightened pressure gradient will maintain breezy conditions. While expected to be more modest than the prior days, daytime gusts generally east of the I-15 corridor/Utah's high terrain will be around 30-40 mph or so. Some gusts on higher ridgelines and exposed terrain may peak closer to 45-50 mph. While humidity will also improve somewhat in comparison to prior days, it'll remain low enough that in combination with the gusts eastern Utah valleys will see another day with areas of critical fire weather conditions, and Red Flag Warnings will remain in effect accordingly.

Sunday night into Monday the front will continue to make slow eastward progression, and the trough will maintain limited shower chances across the north through the morning. While to an extent dependent on cloud cover and how much winds relax, morning lows in some northern valleys (such as the Cache) and mountain valleys such as the Wasatch Back will see some potential for localized frost. Models support a lobe of the trough then cutting off and diving southward near the California/Nevada border, while the broader trough will start to shift and eject out of the region. In turn, the front more or less stalls and starts washing out, and then gradually lifting northward. Afternoon highs Monday generally start to increase, though remain well below normal. Winds will also remain much more modest.

Moving towards midweek energy will continue to maintain a general broad W CONUS trough. The aforementioned cutoff lobe within this broader troughing will also gradually lift through in the Tuesday/Wednesday time frame. This setup will more or less continue the warming trend, and allow a low chance of afternoon showers, mostly in the high Uintas. By Thursday daytime highs will return to near seasonal normal values. While there is some uncertainty on just how exactly the mean western trough evolves, the general consensus suggests some deepening to it and in turn enhancement of southwesterly flow over the region. As such, would expect wind gusts to trend upwards until the trough shifts east or ejects out of the area, which seems to be the primary source of uncertainty (and fairly equally weighted in ensemble members).

AVIATION

KSLC...Breezy northwesterly winds gradually taper overnight, becoming light after ~9z. Northwest winds reinvigorate after 18z, with gusts to 20 kts through the evening. There is a low-end (10%) chance for showers to impact the terminal between 22-00z Sunday. Otherwise, dry conditions prevail through the period under a persistent mid-level cloud deck.

REST OF UTAH AND SOUTHWEST WYOMING...VFR conditions continue for all terminals through the period. Breezy post-frontal northwesterly winds ongoing across most of the northern portion of the airspace will taper off overnight. Breezy southwest winds continue across southern and southeast Utah overnight, becoming strong again with gusts 30-40 mph Sunday afternoon. There are low- end (10-20%) chances for showers and thunderstorms to impact terminals across far northern Utah and southwest Wyoming Sunday afternoon and evening, with main concerns being lightning and periods of decreased CIGS.

FIRE WEATHER, Issued 1242 PM MDT Sat Jun 27 2026

Temperatures Sunday will run 20-25 degrees below normal across northern Utah, and 10-15 degrees below normal across central and southwest Utah.

A warm and dry airmass will remain across south central into east central Utah Sunday, and combined with gusty northwest winds will bring another day of critical fire weather conditions across the eastern valleys. Drier air spreading into southwest Utah along with gusty winds will allow for elevated fire weather conditions across zone 495 during the afternoon hours, but the threat should remain marginal/isolated enough to not warrant any fire weather headlines.

A warming and drying trend will follow across the region through the upcoming week, with temperatures returning to near normal by Wednesday. Strengthening southwest flow during the latter half of the week, coupled with an increasingly hot and dry airmass will likely bring a return to widespread critical fire weather conditions Thursday and Friday.

SLC WATCHES/WARNINGS/ADVISORIES

UT...Red Flag Warning until midnight MDT tonight for UTZ482-484-488- 492-493-495>497.

Red Flag Warning until 9 PM MDT Sunday for UTZ489-494-498.

WY...None.