textproduct: NWS Flagstaff

SYNOPSIS

Mild temperatures are expected to continue through the next week. Chances for showers are forecast through early Friday, followed by drier conditions over the weekend. Unsettled weather returns next week as several disturbances cross the state.

DISCUSSION

A weakening shortwave trough was moving across the southwest states Thursday afternoon. The system has tapped into subtropical moisture but contains weak dynamics for large-scale lift and only modest terrain induced upslope flow. As a result, look for periods of drizzle or light rain with general rainfall amounts of a Trace to 0.20 inches through Friday morning over most of the area. In the upslope regions, especially along the southern edges of the Mogollon Rim and Kaibab plateau, additional rainfall amounts of 0.25-0.50 inches are forecast through early Friday. Also, the mild subtropical air mass will result in elevated snow levels, ranging from 9,000-10,000 feet through tonight, perhaps lowering to the 8,000-9000 foot level on Friday. As a result of the mild subtropical nature of the air mass the saturated layer will mainly be made up of super-cooled water drops not ice crystals. So, any snowfall at higher elevations will be fleeting and mostly due to very localized orographic effects. The trough will rapidly move eastward later on Friday with diminishing showers and, most likely, dry weather by Friday evening.

For Saturday and Sunday...High pressure and dry weather will dominate the weekend weather. Look for periods of high clouds as high level moisture spins off an upstream trough over the Pacific. Otherwise, light winds with temperatures 5 to 10 degrees above seasonal averages are forecast. A few showers could slide into northwest Arizona Sunday night with a very weak passing disturbance.

From Monday onward...Look for a week of unsettled weather. A series of shortwave troughs will brush northern Arizona resulting in periods of showers. Monday looks like another drizzly, light rain day. As the week progresses the shortwaves are expected to move from a progressively more northerly direction providing some hope for lower snow levels. At this time, a few solutions are developing a decent snow storm for the mountains of northern Arizona later next week but confidence is low. In any event, a bit more winter appropriate weather appears in store. Stay tuned.

AVIATION...Friday 02/06Z through Saturday 03/06Z

MVFR and IFR conditions expected through at least 16Z due to -SHRA and FG. Mountain obscuration will also be an issue until early morning. We cannot rule out LIFR visibilities and ceilings at KFLG, KGCN, and KSEZ until 09Z. Expect improving conditions around 18Z. Winds will remain south through west 5-15 kts through the period.

OUTLOOK...Saturday 03/06Z through Monday 05/06Z...VFR conditions should return for the outlook period. Light and variable winds expected during the overnight periods, becoming southerly 5-15 kts Friday and Saturday afternoon.

FIRE WEATHER...Tonight through Saturday

Isolated to scattered rain showers will persist mainly along upslope regions through late tonight. Precipitation will taper overnight as the airmass begins to dry out from west to east. Friday and Saturday remain dry with temperatures 5 to 15 degrees above average. Light southerly winds overnight will shift to the west-northwest on Friday, 5 to 15 mph. Light southerly flow, under 10 mph, returns on Saturday.

Sunday through Tuesday...The unsettled weather pattern persists next week. Temperatures remain 5 to 15 degrees above average on Sunday, cooling gradually Monday and Tuesday. Chances for precipitation return on Monday, mainly in the form of rain showers, persisting into Tuesday. Southwest winds return for Sunday and Monday, 10 to 20 mph, becoming lighter on Tuesday.

FGZ WATCHES/WARNINGS/ADVISORIES

None.