textproduct: NWS Flagstaff

SYNOPSIS

Expect active Monsoon conditions this week, along with cooler daytime temperatures.

DISCUSSION

High pressure will retreat eastward over the next several days, as a long-wave trough forms over the eastern Pacific. This will allow capping to weaken and southerly flow to increase across the region. This is a good recipe for active weather and we expect moderate to high grade Monsoon conditions through much of the week as a result.

With the active conditions comes more cloud cover and rain-cooled air. The warm temperatures that stuck around for most of last week will continue to cool each day, heat related headlines will not be needed.

By the end of the week and into next weekend, there is potential for some drying, as the west coast trough attempts to move inland. This could bring drier, mid-level air and effectively reduce convection over our state. However, if the trough does not move inland as much or if it ejects farther north, it may just keep our active weather going. For now, we have tapered off PoPs a little bit, but we will need to watch this pattern closely, as any change on the trough position could make a big difference.

AVIATION...Tuesday 11/18Z through Wednesday 12/18Z

Mainly VFR conditions expected outside of thunderstorms. ISO -SHRA/-TSRA, becoming SCT-NMRS SHRA/TSRA after 20Z, with the greatest storm activity along and south of a KGCN-KFLG-KSJN line. Brief MVFR/IFR conditions and gusty outflow winds in excess of 45 kts are possible in and around +TS. Storm activity is forecast to decrease after 03Z, though outflow may continue to support ISO SHRA/TSRA near KPRC and KINW until 05Z or 06Z. Outside of storms, expect W-SW winds 5-15 kts, becoming light and variable overnight.

OUTLOOK...Wednesday 12/18Z through Friday 14/18Z...Mainly VFR. SCT- NMRS SHRA/TSRA each day from 19Z-03Z, especially over the higher terrain. Brief MVFR/IFR conditions and gusty outflow winds in excess of 40 kts possible in and around +TS. Otherwise, daytime winds W/SW 5-15 kts, becoming light and VRB overnight.

FIRE WEATHER...Tuesday and Wednesday

Expect active Monsoon conditions each day, with scattered to numerous showers and thunderstorms. Outside of thunderstorms, expect generally light winds. Daytime temperatures will decrease as cloud cover and rainfall increase.

Thursday through Saturday...Active conditions continue Thursday with some drying developing by Friday and Saturday. Daytime temperatures will continue to trend downward. Expect southwesterly winds at 10 to 15 mph each afternoon.

FGZ WATCHES/WARNINGS/ADVISORIES

None.