South Twin Sister
Weather Forecast, United States

Mount Saint Helens

Mount Saint Helens

 

Days 0-3 South Twin Sister Weather Summary:

A heavy fall of snow, heaviest during Thu morning. Temperatures will be below freezing (max 0°C on Wed night, min -12°C on Thu night). Winds decreasing (extremely windy from the SSW on Thu morning, light winds from the W by Fri morning).

Days 3-6 South Twin Sister Weather Summary:

A heavy fall of snow, heaviest during Sat night. Temperatures will be below freezing (max -4°C on Sun night, min -9°C on Fri afternoon). Winds decreasing (gales from the SSW on Sat night, calm by Mon afternoon).

PM night AM PM night AM PM night AM PM night AM PM night AM PM night AM
heavy snow
heavy snow
light snow
light snow
heavy snow
heavy snow
moderate snow
snow showers
snow showers
light snow
snow showers
moderate snow
moderate snow
heavy snow
heavy snow
heavy snow
heavy snow
moderate snow
Wind km/h
50 WSW50
50 WSW50
30 SSW30
15 S15
70 SSW70
105 SSW105
75 WSW75
50 WNW50
20 W20
15 W15
10 SSW10
20 SSW20
20 S20
65 SSW65
45 SW45
50 SW50
25 SSW25
15 SE15
heavy snow heavy snow light snow light snow heavy snow heavy snow mod. snow snow shwrs snow shwrs light snow snow shwrs mod. snow mod. snow heavy snow heavy snow heavy snow heavy snow mod. snow
See all weather maps
Rain
Rain mm
- - - - - - - - - - - - - - - - - -
Snow
Snow cm
15 19 5 2 16 17 10 6 1 2 1 8 9 34 16 18 12 6
High °C
-6 -7 -7 -4 0 -1 -10 -11 -10 -9 -8 -8 -7 -5 -5 -5 -4 -4
Low °C
-6 -7 -7 -6 -2 -5 -11 -12 -10 -9 -9 -9 -8 -6 -6 -6 -6 -6
Chill °C
-16 -18 -15 -11 -10 -12 -24 -21 -18 -15 -12 -15 -16 -16 -15 -15 -7 -9
Freezing level m
1350 1100 1100 1200 1900 1900 850 450 550 650 0 450 750 1000 1300 1350 1200 1350
Sea lvl3000ft6000ft9000ft12000ft15000ft
mountain backdrop
-6-7-7-40-1-10-11-10-9-8-8-7-5-5-5-4-4-1-2-2-122-5-6-6-6-5-5-3-2-1-1-1-1645478201101235544
Sunrise
- - 7:56 - - 7:56 - - 7:56 - - 7:58 - - 7:58 - - 7:58
Sunset
4:12 - - 4:13 - - 4:13 - - 4:14 - - 4:14 - - 4:15 - -

Issued local time.

This table gives the weather forecast for South Twin Sister at the specific elevation of 2134 m. Our advanced weather models allow us to provide distinct weather forecasts for several elevations of South Twin Sister. To see the weather forecasts for the other elevations, use the tab navigation above the table. For a wider overview of the weather, consult the Weather Map of Washington.

Live conditions reported by 5 closest weather stations

Weather StationTemp.WeatherWind
Cloud
Visibility
Cloud / Visibility
Lyman
19 km S
155m alt.
1 hour ago
7° C
light rain
Light rain.
0
Calm
(0 kph at 36).
Bellingham
25 km WSW
198m alt.
2 hours ago
7° C
Dry
0
Calm
(0 kph at 315).
Deming
25 km WNW
102m alt.
1 hour ago
8° C
Dry
5
Calm
(5 kph at 117).
Bellingham
29 km W
71m alt.
2 hours ago
9° C
Dry
0
Calm
(0 kph at 310).
Bellingham
32 km W
130m alt.
2 hours ago
5° C
Dry
10
Light winds from the ESE
(10 kph at 115).

* NOTE: not all weather observatories update at the same frequency which is the reason why some locations may show data from stations that are further away than known closer ones. We also include passing Ship data if it is recorded close to South Twin Sister and within an acceptable time window.