Marine Weather and Tide Forecast for Gardiner, MT

DISCUSSION

Today through Sunday...

Satellite imagery shows an upper level ridge over the northern Rockies and an upstream cut off low off the Pacific coast. There is a shortwave tracking thru northern AB into SK which will bring a weak backdooring wind shift later today and tonight, but without much impact in terms of temps as the ridge and warmer air emerging from the SW remain dominant the next couple of days. Look for temps in the 70s to near 80F today, then mostly 80s Tuesday (likely to be the warmest day yet of 2026). Wednesday will see the onset of height falls as the thermal low shifts to our east, thus upper 60s west to mid 80s east for highs. Winds today & tomorrow will not be strong (only modest breezy mixed winds over the western foothills Tuesday), but deepening lee side low pressure supports higher pre-frontal gusts on Wednesday...perhaps up to ~45 mph in the west. The heat, dry air and breezy winds suggest Wednesday is the most concerning day with regard to fire wx, but greening is underway and will limit the grass fire risk. That said, we are looking at very warm temps, nearing record highs in spots, so please take care to not spark a fire.

Weather gets much more interesting starting late Wednesday as the aforementioned Pacific low gets ejected through the intermountain west in some fashion, while more energy drops out of NW Canada and potentially phases with it into Thursday/Friday. First some things we know. Synoptic scale ascent increases late Wednesday into Thursday as the low takes on a negative tilt as it approaches. So showers likely including mountain snowfall. There is a low risk of t-storms as well, which may include Wednesday night east of Billings per the strong forcing w/ the low. On the back side of the low, NW winds will increase and could become quite strong for Thursday and to a lesser degree into Friday. This brings us to the many uncertainties. The precise track of the low will dictate precip location/magnitude as the low moves into MT/WY and with the associated trowal on its back side. As always, a track thru northern WY keeps us in its diffluent region longer (thus wetter), while a track more quickly into MT supports more wind. Ensembles show a solid signal for post-frontal NW winds especially from Billings eastward, where the probabilities for 60+ mph gusts are 30-70% (greatest along the east side of the Bighorns and close to the Dakotas border). Ptype is also a concern as dynamic cooling could force a changeover to wet snow, which could be significant.
The probabilities for 3+ inches of snow from Wednesday to Friday are non-zero across lower elevations, at roughly 10-30%, greatest over the higher hills. Mountains will pick up several inches of snow (6-12") during this time. Implications with the shortwave dropping out of Canada are quite interesting as if there is enough phasing with the initial low, the entire system slows up and impacts persist thru the end of the week and into the weekend.
Ensembles show a great deal of spread here, but cluster analyses support below normal heights and cyclonic flow through the weekend. As a result, we can be confident of cooler than normal temps Thursday thru Sunday, with at least a low chance of precip each day.

Potential impacts with the Wednesday night-Friday system include travel (due to wind and maybe snowfall) and hazardous conditions for young livestock (per cool/wet/windy weather). Please monitor the forecast over the coming days as details become clearer.

JKL

AVIATION

VFR conditions will prevail across the area through the forecast period. No significant impacts to aviation are expected. BT

PRELIMINARY POINT TEMP/POPS

Tdy Tue Wed Thu Fri Sat Sun ------------------------------------------------------- BIL 079 047/086 053/077 039/047 031/046 027/049 028/049 0/U 00/U 14/T 87/O 34/J 21/B 12/W LVM 077 044/080 047/067 034/043 025/042 021/046 023/047 0/U 00/N 05/T 98/O 45/J 22/J 12/J HDN 080 042/087 050/081 037/048 028/047 025/050 027/051 0/U 00/U 14/T 98/R 35/W 22/J 12/W MLS 077 044/085 054/084 038/046 028/043 025/046 025/048 0/U 00/U 02/T 79/T 33/J 21/B 11/B 4BQ 078 043/084 054/083 037/046 029/044 025/046 026/050 0/U 00/U 01/B 69/T 32/J 21/B 11/B BHK 075 041/084 049/084 036/046 025/040 022/042 022/047 0/U 00/U 01/B 49/T 42/J 21/B 11/B SHR 078 040/085 046/080 035/046 024/043 020/046 022/047 0/U 00/U 02/T 79/O 45/J 32/J 22/W

BYZ WATCHES/WARNINGS/ADVISORIES
MT...None.
WY...None.