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KEY MESSAGES

- Saturday could be the hottest day of the summer with temperatures possibly reaching close to 110 in places. A Excessive Heat Watch has been issued that covers Saturday night as low temps Saturday night are expected to be in the low to mid 70s in most places.

- Northwest winds ramp significantly Sunday in the wake of a frontal system. Critical fire weather conditions can be expected with very low humidities (~10%) and winds 15-25 mph with possible gusts to 40 mph.

DISCUSSION

WEATHER PATTERN OVERVIEW:

Weak cool push from Canada will knock high temps down a few degrees across the area today, otherwise the upper ridge covering most of the country will help to bring a return of the heat by Saturday.

Today will feature mid clouds exiting the area to our east with a few thunderstorms possibly dropping southeast into the CWA this afternoon. Wind gusts of 60 mph are possible with these storms.

Another disturbance may move in from central Montana Thursday night and exit Friday, then the heat is on with temps reaching the 90s to around 100 and going further Saturday with only the northeast zones reaching the 90s while the rest of the CWA is expected to reach 100 to 110.

An excessive heat watch has been issued for the entire CWA Saturday through Saturday night as overnight temps will only fall into the 70s then rebound into the low to mid 90s Sunday.

But northwest winds ramp significantly Sunday in the wake of a frontal system. Winds of 15 to 25 mph with possible gusts to 40 mph are possible. Combined with very low humidity (~10% in many places), this will likely be a critical day for Fire Weather. But winds do look to back off late in the day that could bring some relief.

By Monday, afternoon high temperatures across the region could be in the 70s and 80s, which would be a 20-30 degree cooldown from Saturday. A slow warmup is expected thereafter.

FORECAST CONFIDENCE & DEVIATIONS:

High confidence in the hot weather Friday and Saturday. Confidence is increasing for critical fire weather conditions Sunday. Low confidence in timing any showers and thunderstorms.

No major deviations from the base forecast were made for this iteration.

TFJ

AVIATION

FLIGHT CATEGORY: VFR.

DISCUSSION: Mainly dry conditions are expected into Thursday evening but isolated showers and storms are possible Thursday morning mainly KGDV and KSDY, possibly KGGW Thursday evening. Any haze from distant fires will lower Slantwise visibility. WINDS: Overall East or Southeast winds will hover at 10 kts through Thursday. But gusty/erratic winds can be expected near thunderstorms.

DENSITY ALTITUDE: Will be a concern especially Saturday with temperatures near or over 100. Extra power and longer runway will be needed for takeoffs.

TFJ

GGW WATCHES/WARNINGS/ADVISORIES

Extreme Heat Watch from Saturday afternoon through Sunday morning for Central and Southeast Phillips-Central and Southern Valley-Garfield-Northern Phillips-Northern Valley-Petroleum- Southwest Phillips.

Extreme Heat Watch from Saturday afternoon through Sunday afternoon for Daniels-Dawson-Eastern Roosevelt-McCone-Prairie- Richland-Sheridan-Western Roosevelt-Wibaux.