textproduct: NWS Flagstaff

SYNOPSIS

Look for daily chances for showers and thunderstorms to continue through early next week, primarily across the higher terrain. Drier and warmer conditions are then expected to develop as a strong high pressure system builds over Arizona.

DISCUSSION

High pressure aloft centered over northeast New Mexico and southeast Colorado early Saturday morning will slowly drift southward through Tuesday then westward toward the end of next week becoming centered over the southern portions of Arizona/New Mexico border. The net result will be daily chances for showers and thunderstorms across northern Arizona through Monday or Tuesday then diminished chances as the position of the high will allow for a bit drier air and a more stable air mass to develop over northern Arizona.

For Today...Monsoon moisture will remain in place. As a result, we're looking at another round of isolated to scattered showers and thunderstorms with a bit more activity than seen on Friday. Southeast flow aloft will continue to favor shower and thunderstorm development midday over the Grand Canyon, Mogollon Rim, White mountains and Chuska Mountains with activity then tending to move north and east from that point. However, deep moisture still resides to the south of the Mogollon Rim and models are showing and increase activity even for Yavapai and Gila Counties. Otherwise, light winds and hot.

From Sunday into Tuesday...Monsoon moisture remains in place with daily chances for showers and thunderstorms. The flow aloft will remain southerly with the bulk of activity expected from the Mogollon Rim and White Mountains northward. Otherwise, with the high remaining over the southwest United States, light winds will continue along with above normal temperatures.

Looking from Wednesday onward...Models appear to be trending toward high pressure aloft becoming centered over southeast Arizona/southwest New Mexico. This solution would bring in a more southwest to west flow aloft which would deliver a drier air mass as well as a capping layer aloft under the influence of weak subsidence. In addition, daytime temperatures will be on the increase, likely eventually rising to the upper 80 to lower 90s in the mountains to 105 to 110 degrees at elevations below 4000 feet. Yeah a bummer, but its still summer after all.

AVIATION...Saturday 22/18Z through Sunday 23/18Z

VFR conditions mostly expected, but brief MVFR conditions possible in heavier SHRA/TSRA. Showers/storms forecast between 18Z-02Z, with greatest coverage along a KFLG-KSOW line and along the AZ/NM border. Outside of gusty/erratic outflow driven winds, look for variable winds 10 kts or less.

OUTLOOK...Sunday 23/18Z through Tuesday 25/18Z...VFR conditions mostly expected. Daily chances for -SHRA/-TSRA possible, primarily across the higher terrain. Outside of gusty/erratic outflow driven winds, look for variable winds 10 kts or less.

FIRE WEATHER...Today and Sunday

Look for isolated to scattered showers and thunderstorms each afternoon and evening across northern Arizona with main focus from the White Mountains and Mogollon Rim northward. Stronger storms will produce gusty and erratic winds and localized heavy rainfall. Away from storms, winds look to be southwest to northwest 5-15 mph each day, becoming variable in the evening and overnight.

Monday through Wednesday...Scattered showers and thunderstorms will continue on Monday, becoming more isolated on Tuesday and Wednesday. Stronger storms will bring gusty and erratic winds and brief downpours. Otherwise, warming daytime temperatures with southwest to west winds at 5-15 mph each day.

FGZ WATCHES/WARNINGS/ADVISORIES

None.