textproduct: Salt Lake City

KEY MESSAGES

- Unseasonable warmth continues today, increasing the threat for heat- related illness for those who are sensitive to heat, without adequate cooling or hydration, or have chronic health conditions.

- Widespread critical fire weather conditions continue across central and southern Utah through at least the middle of the upcoming week due to persistent gusty winds. - High-based showers and thunderstorms are capable of producing gusty outflow winds and dry lightning across northern Utah this evening. Winds may also produce areas of blowing dust this afternoon.

DISCUSSION

A shortwave trough digging into the PacNW today has resulted in widespread gusty south to southwesterly winds developing across Utah and southwest Wyoming this morning. Strongest gusts 40-45 mph are being observed across central and southern Utah, where coupled with very dry conditions, will allow for critical fire weather conditions to continue through this evening -- avoid activities that could cause a spark. Winds are less intense across northern Utah, with gusts generally 20-35 mph for most locations. In addition to fire weather concerns, these winds may produce areas of blowing dust through this evening, impacting visibility in some locations especially across the West Desert.

A mostly dry cold front associated with the aforementioned shortwave sweeps through northern Utah this afternoon and into the late evening. Meager amounts of mid-level moisture nudging in along with this frontal boundary will allow for the development of some isolated to scattered high based thunderstorms through the late evening, with potential to produce dry lightning and gusty and erratic outflow winds to 50 mph. This will create a conditional fire weather threat for any storms producing lightning that could spread rapidly due to associated outflows. Any convective activity is expected to wane by midnight.

Lighter post-frontal winds are expected Sunday across northwestern Utah. However, winds remain gusty across central and southern Utah, especially the eastern portions, allowing critical fire weather conditions to continue across these areas. Winds ramp down areawide through the evening as Utah and southwest Wyoming as the first shortwave lifts northeastward out of the region.

Ensembles still have high confidence in a second, deeper trough digging into the Great Basin on Monday into Tuesday. Widespread wind gusts in excess of 30 mph are likely areawide beginning Monday afternoon, with a 70-90% chance. Some locations across central and southern Utah even have a 40-60% chance for gusts in excess of 40 mph,. Another round of critical fire weather conditions is expected as a result. This system will bring better dynamics and a bit more mid-level moisture transport, supportive of more robust convective development mainly across far northern Utah on Tuesday.

REST OF UTAH AND SOUTHWEST WYOMING

VFR conditions will continue to prevail for all regional terminals through today under largely clear skies. Gusty southerly winds will remain in place, with widespread gusts 20-35 kts into this evening. High-based showers will develop across northwestern Utah after 00z bringing a wind switch to the northwest, and a 30% chance of brief wind gusts over 35kt to the west deserts and Wasatch Front.

FIRE WEATHER

There is a conditional fire weather threat across portions of far northern Utah late this afternoon and evening as there is potential for isolated to scattered dry thunderstorms across the area. Storms will be capable of producing dry lightning as well as gusty and erratic outflow winds to 50 mph, which could lead to rapid fire spread given a spark. Otherwise, widespread critical fire weather conditions are expected across central and southern Utah as wind gusts 30-40 mph continue through this evening. Winds remain elevated in some locations overnight, with poor overnight recoveries. While winds taper slightly on Sunday, widespread gusts 25-30 mph will keep critical fire weather conditions in place through the evening. Overnight RH recoveries improve Sunday into Monday morning behind the front, but very efficient mixing ahead of another system moving into the region will result in critically dry RH and widespread wind gusts 30-40 mph again across southern Utah beginning Monday afternoon. Widespread critical conditions remain through Tuesday before becoming more localized Wednesday into Thursday.

SLC WATCHES/WARNINGS/ADVISORIES

UT...Red Flag Warning until 10 PM MDT Sunday for UTZ484-489-492>498.

Fire Weather Watch from Sunday evening through Wednesday evening for UTZ484-489-492>498.

WY...None.