textproduct: Salt Lake City

KEY MESSAGES

- Areas of critical fire weather conditions will continue across far southern Utah through the afternoon.

- A quite unseasonably cold storm system will result in temperatures 10-20F below normal by Monday along with accumulating mountain and mountain valley snow Sunday night into Monday, significant for the Western Uinta mountains and in southwest Wyoming. - Freeze conditions will impact many Utah valleys outside of the Wasatch Front Monday and Tuesday mornings. Areas that will see the greatest impacts include west central Utah, southwest Utah, and the Sanpete and Sevier valleys.

- Temperatures will steadily warm during the upcoming week as conditions stay generally dry, with maxes expected to run up to 10F above seasonal normals for next weekend.

DISCUSSION

A cold Pacific Northwest trough is centered over the Great Basin this morning with the associated surface front near a KMLF-KRKS line. Precipitation is developing over northern Utah as the main trough noses into the area. Coverage of precipitation, valley rain and mountain snow, will increase during the afternoon, with a frontal band becoming more evident by late afternoon with increasing fgen forcing. With cloud cover and colder air having moved in, northern Utah temperatures will run up to 15F below seasonal normals while temperatures will be more seasonable over southern Utah.

The center of the trough is on track to move across the area late tonight into Monday morning, and this will be the time of most widespread precipitation. Snow levels are expected to drop into the 5,000 to 6,000 foot range at this time, with all of Utah's mountains seeing accumulating snow. Most significant accumulations will be over the western Uinta mountains, with guidance showing accumulations over a foot, as guidance keeps precipitation going longer for eastern portions of the area. Given expected impacts, have stuck with a Winter Weather Advisory at this time. An advisory is also in place for southwest Wyoming, as accumulations should be significant enough to produce travel impacts.

Guidance overall is a bit faster moving the system out than previously, with the majority of precipitation ending late Monday morning. Northeastern portions of the area will continue to see the potential for a few showers into the afternoon hours. Monday will be the coldest day of the forecast, with highs up to 20F below seasonal normals areawide, more typical of early March. Many valley locations outside of the Wasatch Front and far southern Utah have the potential to see frost or freeze conditions. Cloud cover may hamper cooling a bit tonight, with Tuesday morning expected to be cooler. Have issued Freeze Warnings for tonight and tomorrow night for the areas most likely to see agricultural impacts, including west central and southwest Utah and the Sanpete and Sevier valleys.

As the trough exits, a weak trailing wave is expected to follow for Tuesday into Wednesday. Overall, guidance is slower with the movement of the system, but the threat of precipitation remains small with it. Another weak wave is expected to move over the building Pacific ridge on Thursday, curbing the warming trend slightly. That being said, temperatures are expected to steadily warm through the week, reaching values up to 10F above seasonal normals by the upcoming weekend, marking quite the seven day temperature rollercoaster.

REST OF UTAH AND SOUTHWEST WYOMING

Scattered showers develop this afternoon across the northern half of the airspace with increasing southerly winds across the southern half. VFR conditions are expected to prevail at all terminals except EVW, where snow showers beginning later this afternoon will likely bring IFR visibility and cigs. A cold front will keep winds out of the north for the northern terminals with gusty southerly winds across the southern terminals. Brief mountain obscuration is expected for the northern half.

FIRE WEATHER

Relative humidities are increasing over Utah today with breezy conditions over southern Utah ahead of a strong cold front. Over far southern Utah, relative humidities remain low enough to combine with the winds to produce critical fire weather conditions. A cold Pacific Northwest trough will cross the area Sunday afternoon through Monday, bringing much colder temperatures and accumulating snow for the mountains. Conditions will trend drier for the upcoming week with a steady warming trend over the next seven days.

SLC WATCHES/WARNINGS/ADVISORIES

UT...Winter Weather Advisory until midnight MDT Monday night for UTZ112.

Freeze Warning from midnight Monday night to 9 AM MDT Tuesday for UTZ114>116-118-119-122.

Freeze Warning from midnight tonight to 9 AM MDT Monday for UTZ115-116-118-119-122.

Red Flag Warning until 9 PM MDT this evening for UTZ497-498.

WY...Winter Weather Advisory until midnight MDT Monday night for WYZ021.