textproduct: NWS Flagstaff

SYNOPSIS

Monsoon moisture will return to the area through the coming week bringing better storm chances, especially for areas along and south of the Mogollon Rim. With the added moisture, hot temperatures begin to trend downward Monday ending up towards seasonal averages later in the week.

DISCUSSION

Monsoon moisture returned to the region Sunday and brought widespread showers and thunderstorms to areas of Gila and Yavapai counties. These storms originated along the higher terrain of the Mogollon Rim but quickly moved westward in the moderate mid-level steering flow. This flow pattern will remain for today, but overall instability levels are forecast to be somewhat lower, partially due to some rain-cooled outflows. Also, areas of clouds and even some showers early this morning may slow down heating later today. We still expect another round of storms along the higher terrain and moving off to the west, just not quite as strong. Otherwise, the sprawling area of high pressure is now centered over the northern plains, but extends southwest into Utah. This general pattern is forecast to persist over the coming week, with the ridge possibly shifting back to the west and centered near the four corners by the weekend. This remains a favorable pattern for monsoon moisture to continue flowing into the region, with day-to-day fluctuations in instability and subtle changes in steering flow dictating which areas are targeted. A particularly active period is showing up in the mid to late week time frame as much of the guidance indicates an inverted trough moving through the south side of the ridge and approaching our region from the east. With the added moisture and clouds around, temperatures will be closer to normal this week for most areas. The exception will be in far northern AZ today and Tuesday where it will be a bit drier. From Page through the Navajo Nation, temperatures will still be several degrees above normal before cooling down mid to late week.

AVIATION...Monday 13/06Z through Tuesday 14/06Z

Storm activity is on the decline, although isolated storms remain south of Interstate 40 in Navajo and Apache counties. MVFR visibilities are possible near the heaviest storms. After 18Z Monday, scattered showers and thunderstorms will redevelop over the higher terrain before moving westward as the day progresses. Brief MVFR/IFR visibilities are possible under the strongest storms. Winds will generally be light through the period, although gusty and erratic downdraft winds of 30-40 kts are possible near thunderstorms. Storm activity will decline overnight.

OUTLOOK...Tuesday 14/06Z through Thursday 16/06Z...Scattered showers and thunderstorms are forecast across most of northern Arizona each day, mainly between 18Z-04Z. Brief MVFR/IFR visibilities are possible under the strongest storms. Daytime winds generally light SW-SE 5-15kts, but gusty and erratic downdraft winds of 30-40 kts are possible near thunderstorms. Overnight, winds will be light and variable or terrain driven.

FIRE WEATHER...Today and Tuesday

Near normal temperatures as monsoon moisture increases. Showers and thunderstorms likely each afternoon along the higher elevations with a 10-30% chance at lower elevations. Gusty and erratic outflow winds with storms. Outside of storm activity, winds S-SE 5-15 mph today, S-W 5-15 mph Tuesday.

Wednesday through Friday...Afternoon and evening showers and thunderstorms likely across most of the region each day with the best chances over the higher elevations. Temperatures near seasonal averages. Winds outside storm activity S-SW 5-15 mph.

FGZ WATCHES/WARNINGS/ADVISORIES

None.