Jefferson County, MS Roof Snow Load - 5 psf
What ASCE 7 says about snow load in Jefferson County
That's Jefferson County's design roof snow load per ASCE 7-22, for a typical heated single-family home - the number a permit reviewer starts from. Flat and low-pitch roofs in Jefferson County are actually governed by ASCE 7's §7.3.4 minimum of 5 psf, not the 3.5 psf the ground-load formula alone would produce.
Converted to something you can actually eyeball on a roof: about 11 in. of fresh powder, 4 in. once it settles and packs down, or just 1 in. if it's turned to ice. Standard residential construction handles a load this size without extra bracing; it is a modest addition on top of ordinary roof loading.
Jefferson County, MS: quick facts
- Design roof snow load5 psf
- Ground snow load, ASCE 7 map5 psf
- National rank#2,419 of 2,758
- Mississippi rank#70 of 82
- Population6,900
- Annual snowfall, NOAA normal0.4 in.
- FIPS28063
Where Jefferson County's figure sits nationally
Out of 2,758 rated US counties, Jefferson County sits at #2,419, the top 88% nationally - #70 of 82 within Mississippi. That's 1.5 psf below Mississippi's own county-average design load of 6.5 psf.
Near 31.7336°N 91.0439°W, FIPS 28063: Jefferson County counts 6,900 residents and a 5 psf map value, which the code's own factors turn into 5 psf.
How much it actually snows in Jefferson County
Most winters bring Jefferson County roughly 0.4 in. of snow - NOAA's normal at UNION CHURCH, MS US, 15.7 mi off. (fresh vs. packed vs. ice explains why.)
Read this before you rely on it
Jefferson County's number above is ASCE 7-22's default case, not a custom calculation: ordinary residential occupancy, heated, sited on ground that's neither fully sheltered nor fully exposed. Any one of those changing - pitch, exposure, heating, occupancy - moves the real figure.
Nothing here substitutes for an address-level number. Get one free, in about a minute, from the ASCE 7 Hazard Tool using your own coordinates rather than Jefferson County's county-wide figure. (How this figure is calculated.)