Sisco Heights has some of the coolest summers among U.S. towns
Midwinter brings lows of about 35°. Winter and summer sit 40° apart. It is a wet place: more rain and snow fall here than on 93% of U.S. towns. Plan time outside from May to September, when highs sit at 64–75°.
A year in Sisco Heights at a glance
Each month’s typical high and low, and what it brings.
What stands out about Sisco Heights’ climate
Compared with towns across the U.S., with Sisco Heights’ place in Washington beside it.
What a year in Sisco Heights feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 223 frost-free days a year
In half of years the last 32° night comes by March 24 and the first by November 2. Frost and day counts come from NOAA’s station at Everett, WA, 11 miles from the town’s center, 350 ft lower.
The 2023 USDA map puts Sisco Heights’ center in zone 8b: the coldest night of a typical winter, averaged over 1991–2020, reaches about 18°. Plant labels use the zone; frost dates tell you when to plant.
Freezing nights by month
Average nights at or below 32°
About 3 inches of snow a winter
Snow, measured at Monroe, WA, falls mostly in February. Precipitation (rain plus melted snow) adds up to 55 inches a year; November is the wettest month and July the driest. Rain or snow falls on about 187 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Sisco Heights
97% of the work is heating, so the furnace matters far more than the air conditioner. Months averaging under 55° run from October through May.
Degree days add up how far each day’s average falls below (heating) or rises above (cooling) 65° over a year. NOAA normals at Everett, WA.
Living with Sisco Heights’ climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
223 frost-free days in zone 8b. The last frost comes by Mar 24 in half of years, so many gardeners wait a week or two past that to set out tomatoes. The first fall frost comes by Nov 2.
Months with highs of 62–84° and lows of 40° or more: May, June, July, August and September. 3.0 miles of trails are waiting.
Parks & trails →Of the yearly building losses FEMA expects in Sisco Heights from natural hazards, earthquakes are the largest share (51%); heat waves, cold waves, winter storms and ice storms together are 10%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Sisco Heights and its neighbors
Marysville the hottest July afternoons (75°, 1° warmer). Differences under a degree are within what the 5 km grid can tell apart. Tap a town to see its climate.
Climates most like Sisco Heights’, farther away
TownRatings’ own comparison of NOAA 1991–2020 normals, not a NOAA product: places of 5,000+ at least 150 miles away, one per state, closest on January low, July high, precipitation and snow.
| Town | Jan. low | July high | Precip. | Snow |
|---|---|---|---|---|
| Sisco Heights, WA | 35° | 74° | 55" | 3.0" |
| Fortuna, CA | 42° | 70° | 55" | 0.7" |
| Sandy, OR | 35° | 80° | 57" | 2.2" |
| Nantucket, MA | 26° | 76° | 44" | 25" |
| Black Mountain, NC | 27° | 82° | 57" | 2.1" |
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value. Snow and frost-free days come from the nearest weather station, so neighbors often share them.
Warmer than it used to be
The last 30 years in Sisco Heights averaged 1.0° warmer than the 1900s. The biggest change is in January (+2.8°).
A smaller shift than in 77% of U.S. towns.
Change by month
The two periods overlap (1991–2000 is in both), which makes the gap a little smaller than it would be between separate periods.
How Sisco Heights compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Sisco Heights’ place among Washington’s.
Sisco Heights weather by month
Highs, lows and precipitation from NOAA’s grid at Sisco Heights’ center; snow, wet days and snow on the ground from Monroe, WA. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 45° | 35° | 7.1" | 0.1" | 20 | 1 | 35° – 45° |
| February | 48° | 35° | 5.0" | 2.2" | 17 | 1 | 33° – 47° |
| March | 52° | 37° | 5.8" | 0.2" | 20 | 0 | 41° – 49° |
| April | 58° | 41° | 4.5" | 0.0" | 17 | 0 | 44° – 54° |
| May | 64° | 46° | 3.4" | 0.0" | 14 | 0 | 51° – 59° |
| June | 68° | 50° | 2.6" | 0.0" | 12 | 0 | 56° – 63° |
| July | 74° | 54° | 1.2" | 0.0" | 6 | 0 | 60° – 67° |
| August | 75° | 54° | 1.4" | 0.0" | 6 | 0 | 60° – 67° |
| September | 69° | 50° | 2.8" | 0.0" | 11 | 0 | 56° – 63° |
| October | 59° | 44° | 5.6" | 0.0" | 18 | 0 | 48° – 56° |
| November | 50° | 38° | 8.1" | 0.3" | 22 | 0 | 40° – 49° |
| December | 44° | 35° | 7.1" | 0.2" | 22 | 1 | 35° – 42° |
| Year | 59° | 43° | 54.6" | 3.0" | 187 | 3 |
How much a month can swing
A normal is an average. February swings the most: from 1991 to 2020 its average ranged from 33° to 47°. September is the most reliable, staying within 7°.
Where Sisco Heights’ numbers come from
Normals are 30-year averages, not a forecast. How TownRatings reads climate data →
- Temperatures and precipitation: NOAA’s gridded 1991–2020 normals for the 5 km cell at Sisco Heights’ center.
- Snow: Monroe, WA.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Everett, WA, 11 miles from the town’s center, 350 ft lower; the nearest station that passes our checks for distance, height and agreement with the grid.
- Growing zone: USDA Plant Hardiness Zone Map, 2023. USDA Agricultural Research Service and PRISM Group, Oregon State University, prism.oregonstate.edu/phzm, accessed 8 Oct 2026.
- Then and now: NOAA’s gridded normals for 1901–2000 at the same cell.
- Storms and extremes: FEMA National Risk Index (expected annual losses to buildings).
Common questions about Sisco Heights’ climate
What is the weather like in Sisco Heights?
A typical July afternoon reaches 74°, a January night drops to 35°, and about 3 inches of snow falls in a normal winter. Milder January nights than 81% of U.S. towns; cooler July afternoons than all but 163 U.S. towns.
How cold does it get in Sisco Heights in winter?
December nights average 35°. About 51 nights a year reach 32° or below. In the coldest December of the last 30 years the month averaged 35°.
How much snow does Sisco Heights get?
About 3.0 inches in a normal winter at Monroe, WA, most of it in February, with snow on the ground about 3 days a year.
How hot does it get in Sisco Heights?
July, with a typical high of 74°. 90° days are rare: none in a normal year at Everett, WA.
When is the first and last frost in Sisco Heights?
In half of years the last spring frost (32°) comes by March 24 and the first fall frost by November 2, about 223 frost-free days, at Everett, WA.
What growing zone is Sisco Heights in?
Zone 8b on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about 18°.
What is the best time of year to visit Sisco Heights?
By one simple rule (highs of 62–84° and lows of 40° or more), May, June, July, August and September. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Sisco Heights getting warmer?
Yes: 1991–2020 averaged 1.0° warmer than 1901–2000 on NOAA’s grid. A smaller shift than 77% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Sisco Heights.
Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000; USDA/PRISM 2023 hardiness zones; FEMA National Risk Index. Today’s forecast: National Weather Service.