Custer, WA Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Custer, a community in Whatcom County, Washington.
This Afternoon
70°F
Mostly Sunny
Mostly sunny. High near 70, with temperatures falling to around 68 in the afternoon. West southwest wind around 3 mph.
7-day forecast for Custer
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| This Afternoon | 70°F | Mostly Sunny | 3 mph WSW | 0% |
| Tonight | 49°F | Partly Cloudy | 2 mph S | 0% |
| Sunday | 71°F | Mostly Sunny | 0 to 5 mph S | 0% |
| Sunday Night | 50°F | Mostly Cloudy | 0 to 3 mph SSW | 0% |
| Monday | 69°F | Partly Sunny | 0 to 5 mph S | 0% |
| Monday Night | 50°F | Partly Cloudy | 1 to 5 mph S | 0% |
| Tuesday | 68°F | Partly Sunny | 1 to 6 mph S | 1% |
| Tuesday Night | 49°F | Mostly Cloudy then Slight Chance Light Rain | 7 mph SSE | 22% |
| Wednesday | 66°F | Slight Chance Light Rain then Partly Sunny | 5 mph S | 22% |
| Wednesday Night | 49°F | Mostly Cloudy | 1 to 5 mph SSE | 12% |
| Thursday | 65°F | Mostly Cloudy | 1 to 6 mph NNE | 13% |
| Thursday Night | 48°F | Mostly Cloudy then Slight Chance Light Rain | 1 to 6 mph NW | 22% |
| Friday | 66°F | Slight Chance Light Rain | 1 to 6 mph NW | 22% |
| Friday Night | 47°F | Slight Chance Light Rain | 6 mph SSE | 20% |
Forecast source: National Weather Service (api.weather.gov) for Custer (48.913, -122.637). Updated through the day.
Growing snapshot for Custer
Last spring frost
Mar 31
First fall frost
Nov 4
Growing season
219 days
Hardiness zone
8b
More local growing data for Custer: nearby ZIP 98240 weather · frost dates · planting calendar · Washington frost dates
Nearby towns & communities
Acme
Bellingham
Birch Bay
Blaine
Deming
Everson
Ferndale
Geneva
Glacier
Kendall
Lynden
Maple Falls
Marietta-Alderwood
Nooksack
Peaceful Valley
Point Roberts
Sudden Valley
Sumas
Climate data from the nearest NOAA station, Blaine, Wa (8.1 mi from Custer). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 20, 2026.