– Lat/Long: 47.51° N 121.74° W

Mount Si
Weather Forecast, United States
Issued: 4 am Tue 12 May Local Time
Updates in:
hr min s
Update imminent

Issued: 4 am Tue 12 May Local Time

Updates in:

hr min s

Update imminent

2 Mount Si Elevations: 2 Forecast Elevations:

	Days 1–3 Weather Summary Heavy rain (total 21mm), mostly on Tue night. Becoming colder with a light covering of snow ,mostly falling on Wed morning. Very mild (max 18°C on Tue afternoon, min 1°C on Wed morning). Winds increasing (light winds from the SW on Tue night, near gales from the WSW by Wed afternoon).									Days 4–6 Weather Summary A moderate fall of snow, heaviest on Fri afternoon. Freeze-thaw conditions (max 4°C on Sun night, min -1°C on Fri night). Winds decreasing (fresh winds from the WSW on Fri night, calm by Sun night).
	Tuesday 12			Wednesday 13			Thursday 14			Friday 15			Saturday 16			Sunday 17
	AM	PM	night	AM	PM	night	AM	PM	night	AM	PM	night	AM	PM	night	AM	PM	night

	some clouds	some clouds	rain shwrs	light snow	mod. rain	light rain	cloudy	light snow	light snow	cloudy	light snow	light snow	light snow	snow shwrs	snow shwrs	some clouds	light rain	some clouds
km/h	ESE	WSW	WSW	WSW	WSW	WSW	WSW	SW	WSW	SW	SW	WSW	SW	NNW	NNW	NNW	NNW	WSW
See all weather maps
cm	—	—	—	5	—	—	—	3	1	—	3	5	2	3	1	—	—	—
mm	—	—	10	—	8	1.4	—	1.2	—	—	—	—	—	—	—	—	0.3	—
max °C	16	18	12	2	4	3	2	3	2	0	0	0	-1	0	0	1	3	4
min °C	15	15	4	1	3	1	1	2	1	0	0	-1	-1	0	-1	0	3	1
chill °C	14	14	0	-5	-4	-5	-5	-4	-5	-6	-6	-8	-7	-4	-7	-3	1	-3

Freezing level m	3800	3650	3050	1500	1950	1500	1550	1500	1550	1200	1250	1100	1150	1300	1200	1350	1800	1750
Cloud base (m)	5700	6400	500	500	400	450	550	450	400	500	400	400	400	700	750	550	850	1650

	5:33	—	—	5:31	—	—	5:31	—	—	5:30	—	—	5:28	—	—	5:26	—	—
	—	—	8:32	—	—	8:34	—	—	8:35	—	—	8:37	—	—	8:37	—	—	8:38

Mount Si Weather (Days 0-3):

The weather forecast for Mount Si is: Heavy rain (total 21mm), mostly on Tue night. Becoming colder with a light covering of snow ,mostly falling on Wed morning. Very mild (max 18°C on Tue afternoon, min 1°C on Wed morning). Winds increasing (light winds from the SW on Tue night, near gales from the WSW by Wed afternoon).

Mount Si Weather (Days 3-6):

A moderate fall of snow, heaviest on Fri afternoon. Freeze-thaw conditions (max 4°C on Sun night, min -1°C on Fri night). Winds decreasing (fresh winds from the WSW on Fri night, calm by Sun night).

This table gives the weather forecast for Mount Si at the specific elevation of 1270 m. Our advanced weather models allow us to provide distinct weather forecasts for several elevations of Mount Si. 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 10 closest weather stations

Weather Station	Temp.	Weather	Wind	Cloud Visibility Cloud / Visibility
Harman Heights wx 6 km SSW 251m alt. 1 hour ago	15° C	Dry	Calm (0 kph at 356).
Renton 30 km WSW 160m alt. 1 hour ago	14° C	Dry	Calm (0 kph at 179).
Black Diamond 32 km SSW 192m alt. 1 hour ago		-	Calm (5 kph at 79).
Grotto wx 35 km NE 321m alt. 2 hours ago	13° C	Dry	Calm (3 kph at 30).
Renton Airport 36 km WSW 218m alt. 2 hours ago	14° C	Clear	Light winds from the NNW (11 kph at 340).	16 km
Grotto wx 39 km NE 1101m alt. 2 hours ago	12° C	Dry	Calm (0 kph at 9).
Auburn 39 km SW 119m alt. 42 minutes ago	26° C	Dry	Calm (0 kph at 254).
Stampede Pass Airport 40 km SE 628m alt. 2 hours ago	11° C	Clear	Light winds from the E (6 kph at 100).	16 km
SHIP627 43 km W 15m alt. 3 hours ago				- km
SHIP6396 43 km W 3m alt. 2 hours ago	15° C

* 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.