textproduct: Salt Lake City

KEY MESSAGES

- High-based showers and thunderstorms will develop across southern Utah late Sunday afternoon and evening. Wind gusts up to 50 mph will occur near high-based convection.

- This threat will shift into northern Utah Monday afternoon and evening, with microburst winds up to 50 mph near any high-based showers and thunderstorms.

- Unsettled conditions will continue through midweek, with the increasing potential for a return to summer-like temperatures late in the workweek to the next weekend.

DISCUSSION

A shortwave trough will continue to shift across southern Utah this afternoon. Upper level ridging currently across the northern Intermountain Region will shift into Utah for the first part of the weekend. Temperatures will continue to trend warmer, around 10 degrees or so above normal by Saturday.

Trends in models continue to show the potential for a coupled jet, with upper level diffluence shifting into southern Utah Sunday afternoon into Sunday evening. This will be associated with mid- level moisture advection, bringing precipitable water values to near the NAEFS 90th percentile by Sunday evening.

Model soundings suggest inverted-v type signatures (as one would expect given the very dry antecedent conditions) in the area of best forcing for Sunday afternoon and evening, generally south of I-70. This will shift north with time, bringing another round of convection to northern Utah including the Wasatch Front Monday afternoon and evening. While any of these high-based showers and thunderstorms will be capable of gusty and erratic winds, expect around a 5% chance of wind gusts in the 50-55 mph range for southern Utah Sunday and northern Utah Monday.

Unsettled conditions will continue into Tuesday across much of the region as an upper level low ejects across the Desert Southwest. Unlike Sunday and Monday, forcing is broad and weak...and while a few thunderstorms are likely, the threat of signficiant microburst activity is less.

By Wednesday, any remnant convection will be much more isolated and tied to the terrain.

Upper level ridging will build into the region Thursday into next weekend...with temperatures more akin to summer than late spring. While guidance the next week shows a range from strong ridging to wandering cut-off lows...the general trend will be toward warmer conditions. There is around 15% chance that KSLC could see the first 90 degree temperature as early as Sunday May 10 or Monday May 11. Obviously this is far in the future, but something to monitor moving forward.

As far as headlines go, Freeze Warnings remain in effect for tonight into Saturday morning for the Sanpete and Sevier Valleys, southern Iron County and eastern Juab and eastern Millard County. This should be the last Freeze Warnings for a bit.

REST OF UTAH AND SOUTHWEST WYOMING

Overall VFR conditions prevail for all regional terminals through the TAF period. Skies remain mostly clear across the airspace, except for some afternoon cumulus buildups mainly across central and southern Utah that may create periods of mountain obscuration. Winds remain generally light through the period, following diurnal trends across the area.

SLC WATCHES/WARNINGS/ADVISORIES

UT...Freeze Warning from 8 PM this evening to 9 AM MDT Saturday for UTZ116-118-119-122.

WY...None.