textproduct: Great Falls

KEY MESSAGES

- Winds gradually decrease through the day today, but another period of strong and gusty winds is likely to occur from Sunday night through Monday morning.

- Temperatures will be well above normal through the next week, with the warmest days occurring on Wednesday and Thursday.

- Dry conditions persist across lower elevations through the next week.

UPDATE

Early morning update has been published, with the main change being to cancel the High Wind Warning for the East Glacier Park Region, Northern High Plains, and Eastern Glacier, Western Toole, and Central Pondera as winds have fallen below criteria and are largely expected to remain below criteria. While a rogue wind gusts approaching high wind criteria remains possible through the morning hours, with cross barrier flow decreasing over Central and North Central Montana the likelihood of widespread high winds has greatly diminished. - Moldan

DISCUSSION

/Issued 410 AM MST Sat Jan 31 2026/

- Meteorological Overview:

H500 shortwave, which brought strong and gusty southwest to west winds to the plains of Central and North Central Montana overnight, will continue to slide east over the International Border and Canadian Prairie Provinces through tonight. This will lead to an overall decrease, albeit slowly, in winds and mountain precipitation across Southwest through North Central Montana through the day today as transitory H500 ridging slides back in over the Northern Rockies. High temperatures will warm some 5 to 10 degrees beneath aforementioned ridge today before another quick moving shortwave begins to flatten the ridge through the day on Sunday. This shortwave will bring another period of strong and gusty winds to the plains of Central and North Central Montana from Sunday night through Monday morning, along with increasing precipitation chances to the Continental Divide.

Northwesterly flow aloft in wake of the departing shortwave on Monday will deliver the "coolest" temperatures of the upcoming week to the Northern Rockies, with temperatures warming precipitously through the middle to end of the work week as H500 ridging amplifies over the Western CONUS. Overall dry conditions are expected beneath the ridge from Tuesday through next Saturday. - Moldan

- Forecast Confidence & Scenarios:

High Winds from Sunday night through Monday morning...

Climate anomaly indicators such as the NAEFS and ECMWF EFIs suggest the potential for another climatologically unusual wind event along the Rocky Mountain Front during the overnight hours of Sunday; however, as compared to the most recent wind event (i.e. Friday night through Saturday morning) the pressure gradient along the Rocky Mountain Front and ridgetop stability will both be significantly weaker. None-the-less, H700 flow per NAEFS analysis is still prog'd to reach 1 to 1.5 standard deviations above normal, with EFIs with respect to winds ranging from 0.5 to 0.6. NBM probabilities for wind gusts in excess of 48kts for both Cut Bank and Mission Lake generally range from a 40-50% chance, with the probability for gusts in excess of 64kts for portions of the Northern High Plains and Eastern Glacier Park Region ranging from a 10-40% chance. Given these overall low probabilities and a lower chance for mountain wave activity we have held off on issuing any High Wind Watches for these areas over this timeframe; however, future shifts will need to monitor later trends.

Mild temperatures through next week...

ECMWF EFIs with respect to high temperatures continue to support a prolonged period of unusually "warm" temperatures, with respect to climatology, across all of Southwest through North Central Montana for the next week as an anomalously strong upper level ridge remains entrenched over the Western CONUS. Confidence is growing in the potential for numerous locations to set or tie record highs during the middle to end of the upcoming work week, most noticeably on Wednesday and Thursday. One thing that could hold temperatures down slightly through the work week would be upper level cloud cover, but with NBM25th Percentile values on Wednesday and Thursday ranging from the upper 50s to mid-60s confidence is high that temperatures will be unseasonably mild. NBM probabilities for temperatures exceeding 70 degrees over the plains of Central Montana even range from a 10- 20% chance on Wednesday to a 20-60% chance on Thursday.

The table below reflects the probability of breaking the current record high temperature for select cities across North Central, Central, and Southwest Montana. - Moldan

LOCATION Wednesday | Thursday Cut Bank 48% breaking 63 degrees | 50% breaking 65 degrees Havre 19% breaking 61 degrees | 46% breaking 58 degrees Great Falls 61% breaking 62 degrees | 88% breaking 62 degrees Lewistown 60% breaking 62 degrees | 90% breaking 60 degrees Helena 29% breaking 61 degrees | 33% breaking 63 degrees Bozeman 35% breaking 62 degrees | 53% breaking 65 degrees Dillon 70% breaking 57 degrees | 92% breaking 57 degrees

AVIATION

31/12Z TAF Period

VFR conditions will prevail throughout the 3112/0112 TAF period; however, strong mid-level winds over Central and North Central Montana through 15-18z Saturday will continue to bring instances of low level wind shear and the threat for mountain wave turbulence. Mountain obscuration will persist through 18z Saturday, with improving visibility thereafter with the exception of the Continental Divide where obscuration is likely for much of the next 24 hours. - Moldan

PRELIMINARY POINT TEMPS/POPS

GTF 57 36 59 41 / 0 10 10 0 CTB 53 35 56 38 / 0 20 0 0 HLN 53 33 53 32 / 0 10 0 0 BZN 52 27 50 26 / 0 0 0 0 WYS 37 14 37 10 / 10 0 0 0 DLN 50 27 52 25 / 0 0 0 0 HVR 52 28 49 33 / 0 0 0 0 LWT 52 31 58 32 / 0 0 0 0

TFX WATCHES/WARNINGS/ADVISORIES

None.