textproduct: NWS Flagstaff

SYNOPSIS

Dry and windy conditions will continue through the beginning of the week. Areas of Critical fire weather each day through Tuesday. Winds begin to diminish by midweek, and daytime temperatures become above normal. Slight chance for showers by the weekend.

DISCUSSION

A longwave trough was stationed over the western states in the early morning hours and is expected to remain in place through Tuesday. The result will be more of the same with southwest winds at 10 to 25 mph gusting to near 40 mph, mainly dry conditions and warm daytime temperatures. The gusty winds and dry conditions will combine to produce near-critical to critical fire weather conditions with a Red Flag Warning in effect for much of northern Arizona today and Tuesday. A bit of moisture has moved over the White Mountains area with a stray dry thunderstorm possible. The main impact should any storms form would be cloud- to-ground lightning and gusty winds but with little to no precipitation.

For Wednesday and Thursday...The trough moves eastward to be replaced by a weak high pressure system. Dry conditions will continue but winds will turn a lighter west to southwest at 5 to 15 mph with a much reduced fire weather threat. Daytime temperatures will turn slightly warmer with mild overnight temperatures.

From Friday onward..Models show a weak high pressure system developing over northwest Mexico. If this scenario transpires the flow would favor some moisture moving over Arizona from the Gulf of California. At this time it looks like moisture amounts would be somewhat limited but likely enough for isolated thunderstorms around the area. A little far out to get too excited and our confidence is low but perhaps the first hint of our annual monsoon.

AVIATION...Monday 08/18Z through Tuesday 09/18Z

VFR conditions. Winds are SW 15-25 kts with gusts 30-40 kts. Winds subside to 5-15 kts after 03Z.

OUTLOOK...Tuesday 09/18Z through Thursday 11/18Z...VFR conditions. Winds SW 15-25 kts with gusts 30-40 kts on Tuesday, becoming SW-W 10-15 kts with gusts 20-30 kts on Wednesday. Winds decreasing to 5-15 kts each night.

FIRE WEATHER...Today through Tuesday

Warm, dry, and windy conditions. There is a slight chance of a dry thunderstorm near the White Mountains this afternoon. Near-critical to critical fire weather conditions. Winds southwest at 15-25 mph with gusts 30-40 mph each day. Afternoon minimum RH 5-15%. A Red Flag Warning is in effect for most of northern Arizona through Tuesday evening.

Wednesday through Friday...Warm and mainly dry. Breezy southwest to west winds at 10-20 mph with gusts at 25-30 mph Wednesday, decreasing to 10-15 mph Thursday and Friday. Minimum RH 5-15% Wednesday and Thursday, increasing to 10-20% on Friday. A slight chance of a high-based thunderstorm near the White Mountains on Friday.

FGZ WATCHES/WARNINGS/ADVISORIES

Red Flag Warning until 8 PM MST /9 PM MDT/ Tuesday for AZZ104>107-109>117-139-140.