Jefferson County School District R-1 Snow Day Predictor
The odds of a closing or a delay on the next three school mornings in Jefferson R-1, measured against Jefferson R-1's own big snow morning of 5.3 inches.
Will Jefferson R-1 close tomorrow?
How Jefferson R-1 calls a snow day
When the call comes
Families and staff are notified by 5:30 a.m.
“The determination to cancel school for an entire day will happen as early as possible. Families and staff will be directly notified by 5:30 a.m.”Source
How families hear
By social media, email, text message, phone call and the district website.
“If this happens, the district uses social media and SchoolMessenger's email, text and phone capabilities to notify families and will post notifications on the district and school websites.”Inclement Weather - Jeffco Public Schools
A 2 hour delay
On a delay morning every school starts 2 hours late.
“Two-hour delay will only be used for extreme weather. Families will be notified by 5:30 a.m. School starts two hours later than the regular start time of your school.”Delay schedule
3 built in snow days
On the 2026 to 2027 calendar, listed as “Potential Snow Make Up Days”.
“Potential Snow Make Up Days Feb. 12*, March 29*, April 30*”Source
Remote learning days
Jefferson R-1 has remote learning days in its winter plan.
“Remote learning days are used if the weather or other emergencies require school closure for multiple days in a row.”Source
Making up a lost day
Three potential snow make up days on the calendar, Feb. 12, March 29 and April 30.
“Potential Snow Make Up Days Feb. 12*, March 29*, April 30*”Source
The 2026 to 2027 calendar
- First day August 19, 2026
- Winter break Dec 21 to Jan 5
- Last day May 27, 2027
Read from Jefferson R-1’s own pages on October 8, 2026; the district site is jeffcopublicschools.org.
Jefferson R-1’s snow record
More 4 inch school mornings than 85% of the 177 Colorado districts with a station record.
- Biggest day 17.9 in on March 15, 2021
- Snowiest winter 2019 to 2020, 108.5 in
- 6 in mornings 0.9 a winter
- 1 in mornings 8.4 a winter
Measured at a NOAA weather station 1.5 miles away. Mornings are the 7 am snow reading on a weekday from December 1 through March 31, over the ten winters from 2016 to 2017 through 2025 to 2026, from NOAA GHCN Daily.
How Colorado counts a lost day
Colorado requires at least 160 days, with 1,080 scheduled hours in secondary school and 990 in elementary. The scheduled hours can drop to 1,056 (secondary), 968 (elementary), 870 (full-day kindergarten) or 435 (half-day kindergarten) to cover conferences, staff training and closings the board judges necessary for student health, safety or welfare.
The Colorado rules in the agency’s own words, and every Colorado district
Districts near Jefferson R-1
| District | Snow a winter | 4 in mornings |
|---|---|---|
| Westminster Public School DistrictWestminster | 50.7 in | 2.3 |
| Denver County School District 1Denver | 46.3 in | 2 |
| Mapleton School District 1Denver | 46 in | 1.3 |
| Littleton School District 6Littleton | 59.5 in | 2 |
| Adams County School District 14Commerce City | 47.8 in | 1.8 |
| Cherry Creek School District 5Greenwood Village | 43.3 in | 1.7 |
148 schools, the 40 largest here
Every school in Jefferson R-1 follows the district’s call: one closing covers them all.
High
- Arvada West High School, Arvada
- Ralston Valley Senior High School, Arvada
- Chatfield High School, Littleton
- Lakewood High School, Lakewood
- Columbine High School, Littleton
- Golden High School
- Bear Creek High School, Lakewood
- Dakota Ridge Senior High School, Littleton
- D'Evelyn Junior/Senior High School, Denver
- Standley Lake High School, Westminster
- Green Mountain High School, Lakewood
- Alameda International Junior/Senior High School, Lakewood
- Pomona High School, Arvada
- Evergreen High School, Evergreen
- Wheat Ridge High School, Wheat Ridge
- Conifer Senior High School, Conifer
- Arvada High School, Arvada
- Jefferson Junior/Senior High School, Edgewater
Middle
- Drake Junior High School, Arvada
- Summit Ridge Middle School, Littleton
- Dunstan Middle School, Lakewood
- Creighton Middle School, Lakewood
- Bell Middle School
- Ken Caryl Middle School, Littleton
- Manning Options School, Lakewood
- Oberon Middle School, Arvada
- Falcon Bluffs Middle School, Littleton
- Carmody Middle School, Lakewood
Elementary
- Three Creeks K-8, Arvada
- Bear Creek K-8 School, Lakewood
- Lincoln Charter Academy, Arvada
- Addenbrooke Classical Grammar School, Lakewood
- Jefferson Academy Elementary, Broomfield
- Fairmount Elementary School
- Prospect Valley Elementary School, Wheat Ridge
- Dennison Elementary School, Lakewood
- Powderhorn Elementary School, Littleton
- Arvada K-8, Arvada
- Mountain Phoenix Community School, Wheatridge
- Lumberg Elementary School, Edgewater
Jefferson R-1 snow day questions
More for Colorado snow days
The odds are a forecast read, and the superintendent makes the call: the district’s own announcement is the one to follow.