1-5 feet of new snow in WA/OR Cascades, May 20-25

The current late-spring storm cycle which began early Sunday morning May 20 has brought copious amounts of precipitation to the Washington and northern Oregon Cascades, with 2-5" already recorded at many locations and another 1-3" expected by Friday. Precip totals so far have been much less in the North Cascades near the crest and the Olympics, with generally under 1" so far except over 4" near Mount Baker and 2" on the SW side of the Olympics, and also south of the Three Sisters in Oregon, with amounts generally under 1" through Wednesday morning. Obviously precip has also been far less east of the Cascade Crest. The precip leader as usual has been Mount Saint Helens with over 5" on the south side (which is the wettest location in the Cascade Range with average annual precip of about 170"), while even the severely rain-shadowed north side of MSH has gotten about 2" so far.

The UW weather model predicts additional precip over the next 2 days of about 1.5-2" for much of the Cascade Range from about Snoqualmie Pass southward throughout the entire Oregon Cascades, with a maximum of about 3" predicted on Mount Rainier. The storm system is now aiming progressively farther south, so the North Cascades which will get much less new (under 1") and be clearing by Friday morning, while the northern CA Cascades near Mount Shasta may get 1-2" of precip during Friday.

Snow levels started out near 8000 ft on Sunday, but plummeted below 5000 ft Monday night into Tuesday. They are predicted to remain in the 4000-5000 ft range over the next 2 days, all the way south throughout the Oregon Cascades and even near 5000 ft on Mount Shasta as the pool of upper-level cold air is pulled southward along the storm's track. Therefore new snow totals are likely to be in the 3-5 ft range above 7000-8000 ft from Mount Baker south to Mount Hood, with lesser amounts of 1-3 ft from 5000-7000 ft and also farther south. Current new snow totals are already up to 6-10" as of 10am Wednesday morning at a few measurement sites above 5000 ft in the WA Cascades and on Mount Hood.

With expected maximum storm totals of 6-7" of precipitation and 4-5 ft of new snowfall by the time things end on Friday-Saturday, this is certainly an unusually potent storm cycle for late May.


Some storm totals as of 10am Wednesday morning, May 23 (new precip since May 20, while new snow is all since May 22 at these elevations):
[tt]
Site Location           Elev  Aspect   New     New   Snow   Notes
                                      Precip  Snow   Depth

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SW BC Coast Mountains:
Squamish River BCRFC    4600   South   1.2"     0"   126"   West of Mt Cayley
Whistler Mountain       5400    NW    no data   0"    93"

---

Vancouver Island:
Jump Creek BCRFC        3700    --     1.7"     0"    99"

---

Olympics:
Hurricane Ridge NWAC    5200   North   0.6"     0"    93"   (listed aspects are
Waterhole SNOTEL        5000   North   0.8"     0"    86"    relative to the
Mount Crag SNOTEL       4000   East    0.8"     0"    72"    entire Olympic Mtns,
Buckinghorse SNOTEL     4900    SW     2.2"     0"   124"    not local slopes)

---

BC Cascades:
Chilliwack River BCRFC  5300    --     2.5"     6"   144"   2 miles N of US border

---

Mount Baker:
Baker Ski Area NWAC     4200    NE     4.3"     0"   174"
Marten Ridge SNOTEL     3500   East    4.8"     0"   116"
MF Nooksack SNOTEL      5000    NW     4.1"     0"   121"

---

North Cascades:
Harts Pass SNOTEL       6500    --     0.3"     0"    82"
Washington Pass NWAC    5400    --     0.4"     0"    77"
Rainy Pass SNOTEL       4900    --     0.9"     0"    72"
Lyman Lake SNOTEL       6000    --     1.0"     5"   120"   NE of Glacier Peak

---

Central WA Cascades:
Stevens Pass SNOTEL     4000    --     2.1"     0"    66"
Stevens Pass NWAC       4000    --     2.1"     0"    78"
Stevens Ski Area NWAC   5200    NW    error     3"   117"
Grace Lakes NWAC        4800   North   1.7"     0"   129"   At Stevens Pass
Alpental Ski Area NWAC  3100    NE     3.0"     0"    88"
Snoqualmie Pass NWAC    3000   North   2.8"     0"    43"
Olallie Meadows SNOTEL  4000    --     3.8"     0"   114"   S of Snoqualmie Pass
Stampede Pass SNOTEL    3800    --     1.9"     0"    56"
Crystal Mountain NWAC   4600   East    1.6      2"    70"
Green Valley NWAC       6200    NE   no data    7"   117"   At Crystal Mtn
Morse Lake SNOTEL       5400   East    1.5"     4"   115"   S of Crystal Mtn
Cayuse Pass SNOTEL      5200    SW     1.5"     5"   140"

---

Mount Rainier:
Sunrise NWAC 6400 -- error 5" 91" NE of Mt Rainier
Paradise NPS Manual     5400   South   3.5"     7"   168"
Paradise NWAC           5400   South   2.8"    10"   164"
Paradise SNOTEL         5100   South   2.7"     6"   141"

---

Southern WA Cascades:
White Pass ES SNOTEL    4500    NW     0.9"     0"    37"
Pigatil Peak SNOTEL     5800   South   1.9"     7"   139"   Very near NWAC site
White Pass NWAC         5800   South   1.7"     7"   135"
Potato Hill SNOTEL      4500   North   1.0"     0"    55"   N side of Mt Adams

---

Mount Saint Helens:
Coldwater Ridge NWAC    3300    --     1.8"     0"     0"   NNW of Mt St Helens
Spirit Lake SNOTEL      3500   North   2.3"     0"     0"
Sheep Canyon SNOTEL     4000   West    4.7"     0"    81"
Swift Creek SNOTEL      4400   South   5.2"     5"   136"
June Lake SNOTEL        3400    SE     5.4"     0"    70"

---

Mount Hood:
Red Hill SNOTEL         4400   North   2.8"     1"    71"
Blazed Alder SNOTEL     3600    NW     2.8"     0"    32"
Timberline Lodge NWAC   5900   South   3.3"     7"   144"
Mt Hood SNOTEL          5400   South   2.1"     3"   113"
Ski Bowl NWAC           3700    SW     1.8"     0"    33"   Snow data at 5000 ft
Mt Hood Meadows NWAC    5400    SE    error     3"   105"

---

Central OR Cascades:
Mckenzie SNOTEL         4800    NW     2.2"     2"    50"   NW of Three Sisters
Three Creeks SNOTEL     5700   East    0.7"     0"     0"   E of Three Sisters
Mount Bachelor          6300   North  no data   0"??  82"   120" at 7300 ft

---

Southern OR Cascades:
Crater Lake NPS Manual  6400   South   0.7"     1"    57"
Annie Springs SNOTEL    6000   South   0.8"     0"    50"   SW of Crater Lake
Cold Springs SNOTEL     5900    NW     0.8"     0"     0"   NW of Pelican Butte
Fourmile Lake SNOTEL    6000   North   0.4"     0"     2"   E of Mt McLoughlin
Billie Creek SNOTEL     5300    SE     0.4"     0"     0"   SE of Mt McLoughlin

---

California Cascades:
Medicine Lake CCSS      6700   South   0.0"     0"     8"
Old Ski Bowl MSAC       7600   South  no data   0"    70"   S side of Mt Shasta
Sand Flat CCSS          6700    SW    no data   0"    20"   SW side of Mt Shasta
Lower Lassen Peak CCSS  8200    SW    no data   0"    97"

---

Site Location           Elev  Aspect   New     New   Snow   Notes
                                      Precip  Snow   Depth
[/tt]

Thanks for the summary Amar. I know there are a lot of people watching the weather this week and into the weekend.

Just to verify, the camp Muir site is the only site above 7k in the Cascade right? I know it's temperature and wind only, so that's why you haven't included it. I just find it helpful to verify freezing levels are just "modeled".

Just to verify, the camp Muir site is the only site above 7k in the Cascade right?

Well, in just the WA Cascades, yes. But definitely not in the whole Cascade Range. Two NWAC sites on Mount Hood are at or above 7000 ft: Top of The Magic Mile chair at Timberline (7000 ft), and Top of Cascade Express, Mt Hood Meadows Ski Resort (7300 ft). The data for the latter site is still not linked properly from the NWAC website, but it exists in the raw data files at www.nwac.us/data/ (look through the ones titled ALL and ALL.x).

In addition, Mount Bachelor Ski Resort provides public access to their raw telemetry data for the past 24 hours at www.mtbachelor.com/cams/24.html , with temps and winds at both 7800 and 9000 ft. The site on the Crater Lake Rim, 7050 ft (which was formerly linked from the NWAC website a few years ago) appears to have been down for some time, not sure if it is being maintained at all anymore.

In the CA Cascades, sites on Mount Shasta ( Old Ski Bowl, 7600 ft , and Grey Butte, 8000 ft ) and Lassen Peak ( Lower Lassen Peak, 8250 ft ) also exceed that elevation, and all have temperature data (Grey Butte has winds too). There is also a site near the summit of Blacks Mountain, 7050 ft , which is a little-known Cascade shield volcano located NE of Lassen Park.