Climbing Forecast › I-90 Corridor › Little Si

I-90 CORRIDOR · METAMORPHIC

Little Si climbing conditions

Good — dry and climbable

Right now

Temp55°F
Wind2 mph
Gusts2 mph
Humidity91.5%
Rain 48hdry
Last rainNone recent

Assessment

No recent rain
Good friction temperature range for metamorphic
High humidity (91.5%) — metamorphic friction compromised, particularly for bouldering
Humidity 91.5% — potential fog/cloud, rock may be damp from condensation

7-day forecast

Scroll through each day — hourly detail is shown inline.

Today Thursday 20 August
Good
Temp57°F
Raindry
Wind2 mph
Gusts2 mph
Humidity84%
No recent rain
  • Metamorphic rock climbs well when dry; tree cover can slow drying
Time °F Rain Wind (mph) Gust Hum
10:00 55° dry 2 — 91.5%
11:00 54° dry 2 — 90.8%
12:00 53° dry 2 — 88.9%
13:00 53° dry 2 — 86.3%
14:00 55° dry 2 — 84.8%
15:00 62° dry 2 — 79.5%
16:00 68° dry 2 — 66.8%
17:00 71° dry 3 — 59.8%
18:00 73° dry 4 — 55.6%
19:00 75° dry 4 — 52.4%
20:00 77° dry 5 — 49.4%
21:00 79° dry 5 — 46.3%
Fri Friday 21 August
Good
Temp63°F
Raindry
Wind1 mph
Gusts—
Humidity75%
No recent rain
  • Metamorphic rock climbs well when dry; tree cover can slow drying
Time °F Rain Wind (mph) Gust Hum
06:00 61° dry 3 — 86.3%
07:00 59° dry 2 — 89.6%
08:00 58° dry 2 — 89.8%
09:00 58° dry 2 — 87.9%
10:00 59° dry 2 — 83.5%
11:00 59° dry 2 — 79.8%
12:00 59° dry 2 — 77.4%
13:00 59° dry 1 — 75.3%
14:00 61° dry 1 — 73.4%
15:00 66° dry 2 — 69.4%
16:00 70° dry 2 — 65.3%
17:00 73° dry 3 — 60.3%
18:00 75° dry 4 — 56.4%
19:00 77° dry 4 — 53.6%
20:00 78° dry 5 — 50.2%
21:00 80° dry 5 — 48.8%
Sat Saturday 22 August
Caution
Temp57°F
Raindry
Wind4 mph
Gusts—
Humidity95%
No recent rainHumidity 95% — potential fog
  • Metamorphic rock climbs well when dry; tree cover can slow drying
  • Damp air — friction edges may feel greasy
Time °F Rain Wind (mph) Gust Hum
06:00 65° dry 5 — 89.7%
07:00 62° dry 4 — 91.4%
08:00 60° dry 4 — 93.6%
09:00 59° dry 3 — 96.5%
10:00 58° dry 2 — 98.1%
11:00 57° dry 4 — 99.4%
12:00 56° dry 4 — 99.5%
13:00 56° dry 4 — 99.7%
14:00 57° dry 4 — 96.7%
15:00 60° dry 4 — 88.1%
16:00 61° dry 4 — 83.8%
17:00 62° dry 5 — 81.1%
18:00 62° dry 4 — 79.9%
19:00 63° dry 5 — 77.3%
20:00 65° dry 6 — 73.6%
21:00 67° dry 6 — 69.3%
Sun Sunday 23 August
Poor
Temp57°F
Rain0.02 in
Wind1 mph
Gusts—
Humidity92%
0.5mm rain forecastHumidity 92% — potential fog
  • Wet metamorphic rock is slick — some overhung walls stay climbable
  • Damp air — friction edges may feel greasy
Time °F Rain Wind (mph) Gust Hum
06:00 60° dry 2 — 81.8%
12:00 57° 0.01 in 0 — 91.5%
18:00 63° dry 4 — 78.4%
Mon Monday 24 August
Good
Temp52°F
Raindry
Wind1 mph
Gusts—
Humidity89%
Should be dry
  • Metamorphic rock climbs well when dry; tree cover can slow drying
  • Damp air — friction edges may feel greasy
Time °F Rain Wind (mph) Gust Hum
06:00 57° dry 0 — 82.5%
12:00 51° dry 1 — 88.7%
18:00 68° dry 4 — 59.6%
Tue Tuesday 25 August
Good
Temp57°F
Rain0.00 in
Wind1 mph
Gusts—
Humidity82%
Should be dry
  • Metamorphic rock climbs well when dry; tree cover can slow drying
Time °F Rain Wind (mph) Gust Hum
06:00 60° dry 1 — 88.5%
12:00 58° dry 1 — 82.2%
18:00 70° dry 3 — 64.1%
Wed Wednesday 26 August
Poor
Temp57°F
Rain0.00 in
Wind2 mph
Gusts—
Humidity97%
Should be dryHumidity 97% — likely fog/cloud
  • Metamorphic rock climbs well when dry; tree cover can slow drying
  • Damp air — friction edges may feel greasy
Time °F Rain Wind (mph) Gust Hum
06:00 60° dry 2 — 90.9%
12:00 57° dry 2 — 96.5%
18:00 63° dry 2 — 76.4%
Thu Thursday 27 August
Good
Temp52°F
Raindry
Wind1 mph
Gusts—
Humidity89%
Should be dry
  • Metamorphic rock climbs well when dry; tree cover can slow drying
  • Damp air — friction edges may feel greasy
Time °F Rain Wind (mph) Gust Hum
06:00 56° dry 1 — 91.8%
12:00 53° dry 1 — 89.2%
18:00 67° dry 3 — 64.3%
Fri Friday 28 August
Caution
Temp52°F
Raindry
Wind1 mph
Gusts—
Humidity92%
Should be dryHumidity 92% — potential fog
  • Metamorphic rock climbs well when dry; tree cover can slow drying
  • Damp air — friction edges may feel greasy
Time °F Rain Wind (mph) Gust Hum
06:00 57° dry 1 — 87.8%
12:00 52° dry 1 — 91.9%
18:00 65° dry 4 — 63.8%
Sat Saturday 29 August
Caution
Temp52°F
Raindry
Wind1 mph
Gusts—
Humidity95%
Should be dryHumidity 95% — potential fog
  • Metamorphic rock climbs well when dry; tree cover can slow drying
  • Damp air — friction edges may feel greasy
Time °F Rain Wind (mph) Gust Hum
06:00 55° dry 1 — 89%
12:00 51° dry 1 — 95.3%
18:00 64° dry 5 — 60.9%
Sun Sunday 30 August
Good
Temp68°F
Raindry
Wind6 mph
Gusts—
Humidity—
Should be dry
  • Metamorphic rock climbs well when dry; tree cover can slow drying
Little Si sits below Mount Si at the western edge of the Cascades, an hour east of Seattle, and holds the region's steepest sport climbing. Access via Exit 32 off I-90 and a 30-minute hike up the popular Little Si trail through old-growth Douglas fir. World Wall's overhanging cave routes stay dry in rain and make it a genuine year-round crag for climbers pulling 5.12 and harder; Interstate Park offers steep pump-fests in the 5.10–5.12 range. The volcanic metamorphic rock ranges from bullet-hard, textured pinches on the steep walls to slick, sharper stone on the slabs. April through October is the fair-weather season, but the World Wall's angle means winter climbing is a real option. Mount Si NRCA trailhead — Washington Discover Pass required.

About Little Si

Little Si sits below Mount Si at the western edge of the Cascades, an hour east of Seattle, and holds the region's steepest sport climbing. Access via Exit 32 off I-90 and a 30-minute hike up the popular Little Si trail through old-growth Douglas fir. World Wall's overhanging cave routes stay dry in rain and make it a genuine year-round crag for climbers pulling 5.12 and harder; Interstate Park offers steep pump-fests in the 5.10–5.12 range. The volcanic metamorphic rock ranges from bullet-hard, textured pinches on the steep walls to slick, sharper stone on the slabs. April through October is the fair-weather season, but the World Wall's angle means winter climbing is a real option. Mount Si NRCA trailhead — Washington Discover Pass required.

Region
I-90 Corridor
Rock type
metamorphic
Aspect
north-east-facing
Altitude
1184 ft
Exposure
medium
Seepage
medium

Other crags in this region

Exit 38 (Deception Crags)