Weather StoryAlmanac, microseasons, and the day's weather story.

Weather in Mammoth, Montana

High country wildflowers peak. Day 59 of spring. Read this microseason across nine climate regions →

Mammoth, MT
Sunday, May 17 at 2:58 AM
34
°
Snow
Feels like
25°
Humidity
62%
Wind
8 mph
Sunrise
5:55 AM
Sunset
8:53 PM
Mammoth, MT
Hour by hour · 24h
56°
8p
51°
9p
47°
10p
45°
11p
44°
12a
43°
1a
42°
2a
42°
3a
41°
4a
40°
5a
39°
6a
40°
7a
43°
8a
46°
9a
48°
10a
51°
11a
53°
12p
56°
1p
58°
2p
58°
3p
59°
4p
58°
5p
57°
6p
56°
7p
L 39°H 59°
Mammoth, MT
7-day forecast
  1. Today
    May 16
    Snow
    54%
    51°30°
  2. Sunday
    May 17
    Heavy Snow
    32%
    41°25°
  3. Monday
    May 18
    Heavy Snow
    25%
    48°25°
  4. Tuesday
    May 19
    Light Drizzle
    11%
    57°33°
  5. Wednesday
    May 20
    Light Snow Shwrs
    30%
    47°33°
  6. Thursday
    May 21
    Overcast
    24%
    58°32°
  7. Friday
    May 22
    Overcast
    26%
    68°42°
Mammoth, MT
Anemometer · 24h winds · from true
NESW
From · True
NW
319° · veering 166°
Direction
NW
319°
Sustained
8
mph
Gust
22
mph
Peak 24h
26
avg 5
Beaufort · 3 · GENTLE BRZ
0
CALM
<1
1
LIGHT AIR
1–3
2
LIGHT BRZ
4–7
3
GENTLE BRZ
8–12
4
MOD BRZ
13–18
5
FRESH BRZ
19–24
6
STRONG BRZ
25–31
7
NEAR GALE
32–38
24h · sust vs gust · mph
avg 5 · pk 26 @ 8:00p
−24h−18h−12h−6hnow
Light breeze veering 166° from the nw.
Mammoth, MT
Barometer · 24h pressure · mb
STORMRAINCHANGEFAIRDRY9901000101010201030
Pressure · mb
812.7
0.0 mb in 3h · steady · 24.00 inHg
Now
812.7
mb
3h
0.0
mb
12h
-0.7
mb
24h
+1.3
mb
Regime · STORM
STORM
RAIN
CHANGE
FAIR
DRY
24h · Pressure · mb
range 811814
−24h−18h−12h−6hnow
Deep low — expect rough seas, strong wind, and persistent rain.
Mammoth, MT
Air quality
47
AQI
Good
PM 2.5
1.4 μg/m³
PM 10
1.8 μg/m³
NO₂
0.9 μg/m³
Ozone
84.0 μg/m³
UV Index
0.1 Low
Mammoth, MT
Almanac · Sunday, May 17
When the dew is on the grass, rain will never come to pass.
Civil dawn
11:22 AM
Sunrise
5:55 AM
Daylight
14h 58m
Sunset
8:53 PM
Civil dusk
3:29 AM
Planting note
Direct sow okra, melons, and southern peas. Thin carrot rows.
Mammoth, MT
The moon
New Moon
0% illuminated
Moonrise
11:55 AM
Moonset
3:35 AM
In sign
♊︎ Gemini
Mammoth, MT
Microseason · 28 of 72
May 16–20

High country wildflowers peak

bird
Jan 137% of the yearDec 31

Read this microseason across nine climate regions →

Mammoth at a glance

  • Today vs. normal: 32°F below the seasonal normal for this latitude
  • Last frost: May 20 (climatological average for this latitude)
  • Microseason: 28 of 72, May 16–20
  • Planting window: Direct sow okra, melons, and southern peas. Thin carrot rows.

Right now in the garden

Cool-season window is open

As of May 17, the cool-season window is open or about to open. Direct-sow peas, lettuce, spinach, radishes, and brassicas now. Hold off on warm-season crops until 1–2 weeks after the last spring frost (around May).

ZIP codes in Mammoth

Climate normals from the Open-Meteo Climate API. Köppen approximation from NOAA NCEI U.S. Climate Regions. See methodology for data sources, editorial rules, and corrections. Maintainer: Brian Tighe.