122 FXUS65 KTFX 272059 AFDTFX Area Forecast Discussion National Weather Service Great Falls MT 259 PM MDT Sun Jun 27 2021 .SYNOPSIS... Aside from some scattered cumulus clouds and perhaps a few showers over the central MT mountains, it will be another warm and dry day across the area. And many more warm and dry days are anticipated across the state this week as highs soar into the 90s and lower 100s by mid-week. Some more mountain showers and thunderstorms are possible during the second half of the week, but little rainfall is expected in lower elevations. && .DISCUSSION... Rest of today through tonight... Decent mid-level moisture has allowed a substantial cumulus field to develop at the top of the boundary layer across the CWA. The greatest cloud coverage is in central and southern areas, where elevated terrain is allowing for easier cloud formation. A few showers are possible through this evening, mainly from the central MT Mountains and Lewistown area south through the Gallatin Range in eastern Gallatin County, but do not anticipate more than isolated coverage. Otherwise, expect fairly quick clearing late this evening through the night as a surface area of high pressure moves across the region and the upper-level ridge begins to more fully nose into the CWA from the Pac NW and SW Canada. Monday through Wednesday... As the region remains in the grips of the ridge of high pressure centered just west of the CWA, each day is expected to get progressively warmer through mid-week. By Wednesday, expect highs for most locations to be at least 10 degrees higher than today. Being on the downstream side of the ridge to the west and upstream side of the trough to the east, and with generally N-NE'ly mid- and upper-level flow, very dry conditions with nary a cloud in the sky and afternoon minimum humidity under 20% expected each day. Aside from some brief, fleeting gusty winds each afternoon in a few areas, winds should remain low enough to preclude truly critical fire weather conditions. That said, expect highs by Wednesday to be 15-20 degrees warmer than normal for most of the area, with many sites at least threatening daily record highs. Thursday through next Sunday... The main difference between the first and second halves of the week will be the expectation for some increased cloud cover and possible showers. This will be due to the ridge axis shifting over and then east of the CWA Thursday and Friday, bringing some SW'ly flow aloft and allowing the ridge to get a bit 'dirty'. That said, the best moisture looks to be limited to the mid-levels, thus any showers or thunderstorms will largely remain in elevated terrain. Temperatures may taper slightly, especially by the weekend, but are still expected to remain well above normal through the end of the period. -Kredensor && .AVIATION... 1115 AM MDT Sun Jun 27 2021 (27/18Z TAF period) VFR conditions are expected through the period. The biggest forecast challenge is likely to be the timing of increasing/decreasing gusty winds this afternoon and evening, mainly between 18z and 03z. A few isolated showers are possible this afternoon and early evening, from northern Gallatin through the Little Belt Mtns to Fergus County. Some modest density altitude issues are possible today, and will get progressively worse over the next few days. -Kredensor Refer to weather.gov/zlc for more detailed regional aviation weather and hazard information. && .PRELIMINARY POINT TEMPS/POPS... GTF 56 90 54 95 / 0 0 0 0 CTB 56 89 55 92 / 0 0 0 0 HLN 59 92 59 97 / 0 0 0 0 BZN 52 88 50 93 / 10 0 0 0 WYS 42 80 38 83 / 0 0 0 0 DLN 51 86 51 91 / 0 0 0 0 HVR 57 92 56 96 / 0 0 0 0 LWT 54 84 52 90 / 10 0 0 0 && .TFX WATCHES/WARNINGS/ADVISORIES... Heat Advisory from noon Tuesday to 9 PM MDT Friday Blaine... Cascade...Central and Southern Lewis and Clark...Chouteau... Eastern Glacier...Eastern Pondera...Eastern Teton...Fergus... Hill...Judith Basin...Liberty...Northern Rocky Mountain Front... Southern Rocky Mountain Front...Toole. && $$ http://www.weather.gov/greatfalls