textproduct: Salt Lake City

KEY MESSAGES

- A warming trend will push daytime temperatures 10 to 20 degrees above normal Monday and Tuesday.

- Gusty southerly winds will develop Tuesday ahead of an approaching storm system. Gusts of 40-50 mph (80% probability) can be expected across western valleys Tuesday afternoon. - A low pressure system will then bring cooler temperatures beginning Wednesday, and lasting through at least Friday. Valley rain and mountain snow will accompany this system mainly north of I-70/US-50, with snow level falling to around 6500 feet.

DISCUSSION

A mid level ridge axis extends across the forecast area this morning, which has allowed warmer temperatures aloft to overspread the area. Mixing 700mb temps around +2C to the surface this afternoon will allow temps to reach the low 70s across most valleys (low-mid 80s in St George & Zion Canyon) this afternoon.

This ridge axis will shift east tonight, allowing a strengthening southwesterly flow to spread across the eastern Great Basin, downstream from an upper low approaching the Pacific Coast. This increasing flow/mixing Monday coupled with additional warming will boost max temps in to the 75-80 range across most valleys, with low- mid 80s across lower deserts of southern Utah both Monday and Tuesday. Gusty south winds Monday will strengthen by Tuesday as 700mb flow exceeds 40 kts across the western half of Utah. There is an 80% chance gusts reach the 40-50mph across western valleys Tuesday afternoon, which may necessitate a Wind Advisory. The chance of gusts exceeding 55 mph is only 15% as of now.

The approaching low pressure system will move inland during the middle portion of the week. A negatively tilted shortwave trough will eject through the eastern Great Basin Tuesday night, lifting a cold front through the forecast Tuesday night into Wednesday morning. A period of valley rain/mountain snow will accompany this ejecting wave late Tuesday night into Wednesday, mainly impacting areas north of I-70/US-50. Snow levels will fall into the 6000-6500 foot range. A longwave trough will remain across the region through the remainder of the week into next weekend maintaining cool temperatures and a chance for valley rain and mountain snow.

With this cooler airmass behind the front, daytime temperatures will run a few degrees below normal (daytime temps in the upper 50s-low 60s) through the remainder of the week. Freezing overnight temperatures will again be a concern across valleys mainly away from the Wasatch Front, and lower deserts of southern Utah.

REST OF UTAH AND SOUTHWEST WYOMING

VFR conditions are expected to persist across all of our TAF sites through the period. Diurnal winds are expected to persist across all of our TAF sites with KCDC and KEVW observing gusts to 20kts this afternoon. Elevated winds are expected across most TAF sites tomorrow afternoon with gusts up to 20kts.

SLC WATCHES/WARNINGS/ADVISORIES

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