textproduct: Salt Lake City

KEY MESSAGES

- A cold front will cross through the forecast area Saturday PM through Sunday AM, bringing light precipitation in the northern area mountains and adjacent valleys. Strong west/ northwest winds will accompany this front across much of northern and central Utah and southwest Wyoming, as well as a portion of southern Utah.

- A significant early season heat wave will develop next week as a large ridge of high pressure builds across the West. Record daily, and monthly, high temperatures are expected.

DISCUSSION

As of 1:20PM, the trough (and the associated cold front) that are expected to bring a significant amount of wind across the forecast area is right on the doorstep as the feature slides across southern Idaho. Over the next 12 hours, a substantial increase in wind speeds at the surface will occur as the surface frontal boundary finally works its way into northern Utah/ southwest Wyoming. While breezy conditions (30-35 mph gusts) are expected directly ahead of the cold front, winds in the post frontal environment are looking like the main concern with this event.

In the wake of the cold front, overhead wind speeds will increase to upwards of 50 to 60kts for a brief period of time, which will attempt to mix toward the surface along (and behind) the cold front. As such, surface wind gusts are expected to be around 45 to 50 mph across much of northern Utah. For areas on the lee side of significant terrain feature, strong downsloping winds are expected to bring wind gusts of upwards of 55 to 65 mph. This will be the case across much of northern, central, and a portion of southern Utah. Areas of particular note for these stronger downsloping winds will be the western Uinta Basin, Castle Country, and Escalante area late tonight/ early Sunday morning. Have expanded the current list of wind advisories to include the Escalante and Capitol Reef area as a brief (~3 hour) period of wind gusts in excess of 45 mph are to be expected in these areas... again, for those areas down-wind of significant terrain features. Additionally, strong gap winds will develop across lower Washington County early Sunday morning as the aforementioned cold front scrapes by to the east. Areas within Black Ridge Canyon (e.g. Pintura) are expected to see a brunt of these strong winds (60 mph), however, areas farther south but still close to the mouth of the canyon (e.g. Toquerville, Hurricane, and La Verkin) are still expected to see strong wind up to 45 to 50 mph.

Winds are anticipated to drop off after the cold frontal passage (with the exception of downslope regions mentioned above) as we head into Sunday morning. In the wake of the boundary, high temperatures on Sunday will be upwards of 15-20 degrees lower than Saturday (especially across northern Utah/ southwest Wyoming). A brief reminder that winter still exists... but not for much longer.

Heading into next week, there is high confidence in a strong ridge developing over the western U.S. Under this ridge, rapidly warming temperatures are expected across Utah and southwest Wyoming. Temperatures are expected to rebound back to above normal levels by Monday, and will continue to rise rapidly through the middle of the week. Along the Wasatch Front, temperatures will be pushing into the upper 70s to low 80s! The current record for earliest 80 degree day in SLC is March 31 (set back in 2012)... NBM probabilities of reaching 80 degrees or higher for Wednesday, Thursday, and Friday are as follows: 60%, 85%, 80%. It seems very likely at this point in time that we will be setting a new record for the earliest 80 degree day by at least 11 days (potentially by 13 days). For the St. George area, the earliest 90 degree day on record current stands at April 2 (set in 1996)... this record is VERY likely to be broken by over 2 weeks as NBM probabilities of 90 degrees or higher rise to 90% by Wednesday and nearly 100% by Thursday.

This will be an unprecedented early season heat wave. Many records are likely to be broken across the region. Continue to monitor forecasts going forward for any changes but, as mentioned above, this is a high confidence forecast.

REST OF UTAH AND SOUTHWEST WYOMING

Westerly winds will continue to increase this afternoon ahead of the cold front, particularly across N-UT/SW-WY where valleys will see gusts to 20-30kts. Mountain showers will also continue ahead of the front, with a low chance of thunder (10% chance). Valleys will likely see mostly virga if anything, though this virga could produce gusty and somewhat erratic outflow winds. The cold front will move into NW-UT by 00-01z, moving through the Wasatch Front by ~06z and reaching S-UT by 10-12z. Very strong northwesterly winds will accompany this front, with many valleys seeing gusts of 35-45kts and prone areas (in higher terrain, downwind of higher terrain) will see even higher gusts exceeding 50kts (KEVW, KPVU most likely). Blowing dust could produce MVFR VIS at times.

SLC WATCHES/WARNINGS/ADVISORIES

UT...High Wind Warning until 3 AM MDT Sunday for UTZ101.

Wind Advisory until midnight MDT tonight for UTZ102>105-107-109.

High Wind Warning from 7 PM this evening to 3 AM MDT Sunday for UTZ106.

Wind Advisory until 3 AM MDT Sunday for UTZ110.

High Wind Warning until 6 AM MDT Sunday for UTZ112-113-117.

High Wind Warning until 3 AM MDT Sunday for UTZ114-120.

Wind Advisory until midnight MDT tonight for UTZ121.

Wind Advisory from midnight tonight to 9 AM MDT Sunday for UTZ123.

Wind Advisory from midnight tonight to 6 AM MDT Sunday for UTZ128-129.

WY...High Wind Warning until midnight MDT tonight for WYZ021.