Webcam and real-time weather data for Snoqualmie Pass: Weather
Denny Mountain is the prominent peak seen to the northwest of Snoqualmie Pass and to the north of I-90. The mountain consists of a one-mile long ridgeline oriented to the NNW with many jagged outcrops. The southern buttress of Denny can be seen towering above I-90 as the road approaches the pass from the west but the actual highpoint of the summit is hidden from eastbound freeway vantage points. The summit can be spotted by westbound drivers from the pass. Its NE face is home to the notoriously challenging Alpental ski area that boasts of having only 3% "easy" slopes and 75% "expert" with 22% in between.
The mountain was named for a member, (or members) of the Denny family, one of several families who were the first settlers in what is now downtown Seattle. Arthur Denny is most often cited in history books relating the early history of the area but his brother, David who staked a mining claim on nearby Denny Creek in the 1890's, is credited as being the creek's namesake and sometimes, the mountain's.
A note on the elevation: The USGS quad for the area shows a summit elevation of 5519' for a point .33 miles to the NW of the actual highpoint of the mountain. Further, other sources give various summit elevations of 5519', 5530' and, most often, 5520'+. On Sept. 21st, my GPS read 5,608' on the summit so lacking better documentation, that's what I'll use for now.
From I-90 eastbound, take exit 53, "West Summit" and turn left, passing under the freeway. Go northwest toward the Alpental ski area on Erste Strasse, aka Alpental access road, aka FR 9040. There is a large parking area 1.4 miles from the end of the freeway ramp.
From I-90 westbound, take the Snoqualmie Pass exit, cross over the freeway, following signs to Alpental. Once the road goes under the freeway proceed as described above.
Northwest Forest Pass or equivalent is needed to park in the lot during hiking season and a Snopark Pass will be needed during ski season.
When To Climb
Since this is a very popular ski area, winter climbers are going to have to dodge skiers and boarders and stick to the sides of the runs. I think the best time would be in the spring after the resort is closed but before the snow has melted, meaning from late spring until at least mid July. See route report "Denny Mountain Bushwhack" for late summer trips.