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KEY MESSAGES

- Very dry conditions will continue over Utah and southwest Wyoming through the weekend. Hot conditions will continue for the remainder of the work week before highs move closer to seasonal normals for the weekend.

- Areas of critical fire weather conditions will continue to impact portions of southern and eastern Utah through Wednesday due to a combination of the very dry conditions and breezy northwesterly winds.

- Another round of gusty winds up to 35-45 mph combined with very dry relative humidity values will bring the threat of critical fire weather conditions to western Utah on Friday.

DISCUSSION

A dry and somewhat breezy west to northwest flow persists over Utah and southwest Wyoming this evening. Skies are clear across the area except for central Utah, where the passage of a weak and dry boundary has brought some scattered high clouds. Conditions remain quite dry, and this combined to create another round of critical fire weather conditions for portions of southern and eastern Utah during the afternoon. Highs were on the hot side again this afternoon with maxes 5-7F above seasonal normals across northern portions of the area and up to 10F above seasonal normals over southern Utah.

Conditions will remain quite dry behind the boundary, with its main impact being to simply curb the warming trend. Thus, the temperature forecast for Wednesday looks similar to today. Winds are expected to relax a bit overnight due to the front, but the pressure gradient is expected to increase again by Wednesday afternoon as the trailing shortwave from the Canadian system moves across Idaho and Wyoming, putting breezy winds back in the forecast and necessitating another Red Flag Warning for the same areas as today.

Behind that trailing shortwave, there is high confidence that the ridge will make its way onshore, settling over the Great Basin for Thursday afternoon. This will bring much lighter flow over the area and bring a very slight increase in moisture for southern Utah, decreasing the fire danger for the area. The ridge continues east thereafter, moving overhead for Friday morning and east of the area for the afternoon. This will bring noticeably warmer temperatures to northern portions of the forecast area, while the approach of a weakly organized Pacific trough (the one nudging the ridge out of the way) will bring modestly less warm temperatures to southwest Utah. Increasingly breezy southerly winds on the back side of the ridge will combine with the continued dry conditions to bring the threat of critical fire weather conditions over western Utah, though there is a chance relative humidity values will be too high across the higher terrain.

The majority of guidance brings the ill-defined trough across northern Utah during the day Saturday. Its position should quickly bring a dry tongue of moisture into southern Utah, wiping out the previous relative humidity gains, but should bring enough moisture and instability for a few showers for northern portions of the area, primarily near the Utah/Idaho border. Highs will most likely return to values within 5F of seasonal normals during this time, with the less warm temperatures continuing into Sunday as lingering shortwave energy from the trough keeps things a bit unsettled.

Behind that trough, the leading solution in guidance is to bring high pressure over the area once again, bringing more hot and dry weather for the upcoming week.

REST OF UTAH AND SOUTHWEST WYOMING

VFR conditions will persist for the entire airspace through the period. Dry and stable conditions with a few high clouds will continue. Smoke from a wildfire northwest of the CDC terminal could slightly limit VIS, primarily during the day.

FIRE WEATHER

Very dry conditions are expected to continue over Utah through Friday, with most valley locations seeing minimum relative humidity values below 10 percent. Breezy northwest winds will persist for Wednesday, bringing another round of critical fire weather conditions to portions of southern and eastern Utah where fuels are critically dry. With high pressure moving overhead Thursday, winds will decrease and so will the fire danger. Winds, however, are expected to pick up out of the south, particularly over western Utah, on Friday, bringing another threat of critical fire weather conditions. There is a lower chance of critical fire weather conditions over the remainder of southern Utah with lighter winds and a small increase in relative humidity values. This increase in moisture will bring a low chance of isolated dry lightning to the mountains of southern Utah for Friday afternoon. A trough will cross northern Utah on Saturday, with relative humidities increasing there, but drier air will move back into southern Utah during this time. Winds, however, will be significantly lighter for the weekend and into early next week, decreasing the fire danger to winds and low relative humidity. There will be a low chance of isolated dry lightning over northwest Utah late Friday into Saturday with this system.

SLC WATCHES/WARNINGS/ADVISORIES

UT...Fire Weather Watch from Friday afternoon through late Friday night for UTZ478-492-495.

Red Flag Warning until 9 PM MDT Wednesday for UTZ482-484-488-489- 493-494-496-498.

Fire Weather Watch from Friday afternoon through Friday evening for UTZ497.

WY...None.