textproduct: Great Falls

KEY MESSAGES

- Breezy winds continue along the Rocky Mountain Front into this evening, resulting in drifting snow and isolated instances of blowing snow along the immediate eastern slopes.

- Dry through the work week, with temperatures trending toward the mild side of average.

- Low probabilities for precipitation begin to arrive toward the weekend, highest along the Continental Divide.

DISCUSSION

/Issued 1253 PM MST Mon Dec 29 2025/

- Meteorological Overview:

Persistent upper level ridging across the western CONUS will keep the region dry through much of the work week. Initial concern this forecast period will be for gusty winds and a localized blowing snow concern along the immediate eastern slopes of the Rocky Mountain Front this afternoon and into the evening. Further east on the adjacent plains, the combination of a lesser snowpack and temperatures rising to above freezing will help limit concerns.

As the ridge nudges eastward through the week the risk for strong winds diminishes along the Rocky Mountain Front. Temperatures continue to moderate toward the milder side of average by tomorrow and look to remain that way through the remainder of the work week.

The next mentionable opportunity for precipitation arrives late week into the weekend, mainly along the Continental Divide, as upper level ridging is flattened by an approaching trough across the west coast. That said, the system this weekend is not overly impressive at this point, which leaves doubt as to how much precipitation will ultimately fall. -AM

- Forecast Confidence & Scenarios:

There are two sources of uncertainty this forecast period. One in the immediate term, and one toward the end of the forecast period.

The initial concern is for the robust pressure gradient that is continuing along the Rocky Mountain Front this afternoon. Latest in- house guidance suggests this pressure gradient is peaking as of the issuance of this discussion, and should slowly wane through the remainder of the afternoon. This should allow sustained winds to gradually diminish from present levels through the evening. As such, I will forego a High Wind Warning at this time. Those traveling along the Rocky Mountain Front should still be aware of the risk for crosswinds through the remainder of the afternoon and early evening.

The other source of uncertainty is with respect to the progression of upper level troughing later this week near the Pacific coastline. Guidance that maintains the troughing as it progresses inland is more favorable for precipitation along the Continental Divide. Conversely, guidance that weakens the troughing significantly results in a much drier scenario. At this point, the probability for 0.10" precipitation along the Continental Divide Friday night into Saturday is roughly 40%. The probability for 0.25" precipitation drops to 20% over that same timeframe. -AM

AVIATION

30/00Z TAF Period

VFR conditions prevail this TAF period under scattered upper level clouds. Aside from breezy winds over western portions of the plains, winds will be rather light this TAF period. -AM/thor

PRELIMINARY POINT TEMPS/POPS

GTF 28 45 32 49 / 0 0 0 0 CTB 23 42 27 45 / 0 0 0 0 HLN 23 39 22 43 / 0 0 0 0 BZN 19 40 19 45 / 0 0 0 0 WYS 5 32 5 37 / 0 0 0 0 DLN 21 40 22 44 / 0 0 0 0 HVR 18 35 19 35 / 0 0 0 0 LWT 25 46 29 51 / 0 0 0 0

TFX WATCHES/WARNINGS/ADVISORIES

None.