Hygiene Weather -- Boulder County, CO

Hygiene, CO -- St. Vrain Creek Community in Boulder County

Hygiene is an unincorporated community with a U.S. Post Office in northern Boulder County, at 5,089 feet on the plains between Lyons and Longmont, with ZIP code 80533. It was first called Pella; the present name comes from the Hygiene Home, a tuberculosis sanatorium that Church of the Brethren minister Jacob S. Flory opened there in 1881. Flory's congregation built the St. Vrain Church of the Brethren in 1880, the denomination's first meetinghouse in Colorado, and the application for the first Hygiene Post Office followed in 1883.

St. Vrain Creek runs past the community on its way from Lyons to Longmont. The creek has monitoring sites at North 51st Street near Lyons and below Airport Road at Longmont, upstream and downstream of Hygiene.

The nearest NOAA climate-normals station is Longmont 2 ESE, about 5½ miles east-southeast at 4,950 feet. Its 1991–2020 normals give a median last spring freeze on May 7 and first fall freeze on October 5 — a 151-day growing season — about 49 days a year at 90°F or warmer, and 15.21 inches of precipitation a year. Hygiene sits about 140 feet higher than the station, so expect its numbers to run close to those.

Fire Risk and History

Hygiene sits on open plains east of the forested foothills, but wind-driven grass fires reach the plains too: strong winds drove grass fires in the Boulder area in January 2006, February 2017 and December 2021. Downslope windstorms reach this far east as well — the January 16–17, 1982 storm gusted to 136 mph at Lyons. To check the wildfire risk rating for a specific address, use the Colorado Forest Atlas risk viewer.

Elevation and Microclimate

At 5,089 feet, Hygiene sits about 140 feet above the Longmont 2 ESE station and well below the foothills towns to the west. The Longmont normals put the median last spring freeze on May 7, which means a later frost still happens in about half of years; the median first fall freeze is October 5. UV exposure at this elevation is noticeably stronger than at sea level, so sun protection matters on summer field and trail days.

Flood Zone Information

The center of Hygiene is in FEMA Flood Zone X, an area of minimal flood hazard. St. Vrain Creek is a different story: in September 2013 the St. Vrain Creek watershed flooded catastrophically, washing out bridges, culverts and diversion structures and damaging long sections of road along the creek corridor. Properties near the creek should check their own parcel on FEMA's Flood Map Service Center.

Nearby Weather Pages

• Longmont weather -- city to the southeast
• Lyons weather -- canyon-mouth town to the northwest
• Niwot weather -- plains CDP to the south

References

• Hygiene, Colorado — Wikipedia
• Longmont 2 ESE 1991–2020 annual normals — NOAA NCEI
• Boulder wind events — NOAA Physical Sciences Laboratory
• Saint Vrain Creek flood recovery — Colorado EWP Program
• St. Vrain Creek at N 51st St near Lyons — USGS
• St. Vrain Creek below Airport Road at Longmont — USGS
• FEMA Flood Map Service Center
• Colorado Forest Atlas