Will Pipes Freeze in Multnomah County, OR? 2 nights a Year
Freeze nights in Multnomah County
In a normal year Multnomah County, OR gets 2 nights at or below 20°F, the point where bare pipes in a garage, attic or outside wall start to freeze. That is more than 9% of US counties.
Risk level: Rare. The risk season runs December to January, worst in December.
It depends where the pipe is
| Pipe | Freezes near | Nights a year |
|---|---|---|
| Outdoor spigot, open crawlspace | 32°F | 31 nights |
| Bare pipe in garage, attic or outside wall | 20°F | 2 nights |
| Insulated pipe in unheated space | 10°F | under 1 night |
| Inside the heated house | 0°F | none |
Foam-sleeving a bare pipe in unheated space takes it from 2 nights of risk to under 1 night. A 12 ft heat-tape kit runs $17 to $37; an average burst-pipe repair is about $500.
Month by month
Nights at or below 20°F in a normal year.
First 32°F night is usually around 11/20, last around 03/16. For 20°F: 01/01 to 01/10.
How cold Multnomah County nights get
Average winter (Dec-Feb) low: 37°F; the coldest month, January, averages 37°F overnight. 7 months normally bring at least one night below 32°F (Jan, Feb, Mar, Apr, Oct, Nov, Dec).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 37°F | 37°F | 40°F | 43°F | 49°F | 53°F | 57°F | 57°F | 52°F | 46°F | 41°F | 37°F |
Multnomah County next to its neighbours
Clark County, WA, 25 km north, gets 5 nights below 20°F to Multnomah County's 2 nights.
| County | Distance | Below 32°F | Below 20°F | Jan low |
|---|---|---|---|---|
| Multnomah County, OR | - | 31 nights | 2 nights | 37°F |
| Clark County, WA | 25 km north | 71 nights | 5 nights | 32°F |
| Clackamas County, OR | 46 km south | 68 nights | 3 nights | 33°F |
| Washington County, OR | 53 km west | 60 nights | 4 nights | 33°F |
| Hood River County, OR | 59 km east | 140 nights | 17 nights | 28°F |
| Skamania County, WA | 64 km northeast | 145 nights | 21 nights | 27°F |
| Columbia County, OR | 68 km northwest | 85 nights | 7 nights | 32°F |
Multnomah County within OR
Multnomah County ranks 31 of 36 OR counties for nights below 20°F. The most is Baker County, OR at 76 nights, with a 20°F average winter low. The fewest is Lincoln County, OR: under 1 night, winter lows near 40°F. At 60 ft, Multnomah County sits 1,957 ft below the state's median county elevation of 2,017 ft.
What to do here
- Watch the forecast for a sub-threshold night.
- That night: drip the faucet on an outside wall, open the sink cabinet.
Why rare cold catches people out - freezes in places that rarely freeze.
Where this comes from
NOAA 1991-2020 climate normals, blended from 3 nearby stations and adjusted for elevation; closest is Portland Troutdale Airport, OR, 1 km away (close match). A normal year, not tonight's forecast: check the forecast low for the night itself. What a "fair" or "distant" station match means is in the method guide.