Flagstaff, AZ
Weather Forecast Office
FXUS65 KFGZ 210418 AFDFGZ Area Forecast Discussion National Weather Service Flagstaff AZ 918 PM MST Thu May 20 2021 .SYNOPSIS...A low pressure system will bring strong southwest winds into Saturday. Dangerous fire weather conditions are expected in many locations over the next couple days. Some moisture moves northward on Friday with a chance for showers and even a stray thunderstorm. Expect mild and dry weather over the weekend. Windy conditions are still expected east of Flagstaff on Saturday with the fire weather threat continuing. Winds will be lighter on on Sunday. Warmer temperatures and lighter winds are forecast early next week. && .UPDATE...Large area of low pressure is moving southward over the West Coast states. A plume of moisture is being drawn northward across Arizona this evening. Light echoes are developing south of our CWA and moving northward. Other light echoes are popping up over western Coconino County. Latest guidance is showing more precipitation later tonight and Friday morning. Have updated forecast to increase POPs and QPF. && .PREV DISCUSSION /254 PM MST/...A strong low pressure system was centered over northwest Nevada during the afternoon hours, diving southward. The result, strong gusty winds and elevated fire danger. A Red Flag Warning remains in effect for most of northern Arizona through 8:00 PM MST this evening. As the low approaches Arizona overnight pressure gradients will strengthen. Winds are expected to remain breezy area wide but downright windy near and downwind of terrain features including Doney Park, Springerville and Interstate-40 east of Flagstaff. A Wind Advisory remains in effect through the night. On Friday...Models continue to pull increasing moisture northward from over the Gulf of California and the Eastern Pacific. The models are now showing a decent chance of showers from Flagstaff eastward along the Mogollon Rim and White Mountains to the Four Corners, especially during the morning hours. Generally light amounts of 0.05 inches or less except for the eastern Mogollon Rim and White Mountains region where up to 0.25 inches will be possible. An isolated thunderstorm or two will not be out of the question. This could have some impact on Red Flag Warnings and Fire Weather Watches on Friday, stay tuned for updates. Otherwise, the low center draws nearer with even stronger winds on Friday. Look for sustained afternoon southwest winds in the 20 to 30 mph range gusting to 40 mph in most locations to near 55 mph across portions of northeast Arizona. These types of wind gusts can loft thicker plumes of dust. Even if there are a few morning sprinkles dry conditions will return for most areas Friday afternoon. The main threat area will be along Interstate-40 east of Flagstaff to the Utah border. On Saturday...It will remain windy. A drier air mass will move across the area with dangerous fire weather conditions continuing. Winds will not be as strong as on Friday generally southwesterly at 15 to 25 mph gusting to near 40 mph. From Sunday onward...Warmer with typical springtime afternoon breezes as the current low moves off to the east. && .AVIATION...For the 06Z package...VFR conditions prevail for the TAF period. Winds remain breezy tonight at 10-20 kts with gusts 25-30 kts over the higher terrain. Areas of low level wind shear through 12Z, particularly along and near a KGCN-KINW-KJTC line. Strong southwest winds at 25-35 kts redevelop after 14Z, with gusts 35-50 kts. A few showers are possible along the Mogollon Rim late tonight and into the morning hours, shifting into east-central Arizona by afternoon. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...Winds remain gusty tonight. Stronger southwest winds develop on Friday, with critical fire weather conditions over much of north-central Arizona. Near-critical conditions are expected in eastern Arizona where RH values will be higher. A few showers are possible late tonight into Friday morning, with thunderstorms in eastern zones during the afternoon. Expect strong winds again on Saturday with critical fire weather conditions possible in eastern Arizona. Sunday through Tuesday...Lighter winds and gradual warming, with dry conditions to start next week. && .FGZ WATCHES/WARNINGS/ADVISORIES...Red Flag Warning from 11 AM to 8 PM MST Friday FOR AZZ104>109- 112-115-116-137-138. Wind Advisory until 8 PM MST Friday FOR AZZ004>017-037>040. Fire Weather Watch from Friday morning through Friday evening FOR AZZ110-111-113-114-139-140. && PUBLIC...MAS/McCollum AVIATION...NL FIRE WEATHER...Humphreys For Northern Arizona weather information visit weather.gov/flagstaff
