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Two things regulars want December visitors to separate: the city and the mountains. On the city — "we haven't had much in the valley the last few years," and anyone hoping to play in snow "may need to go to Park City" for it. On getting around — "SLC and Utah do an excellent job of clearing snow from the roads," with crews out once there are a couple of inches and plowing until it stops, so a snowy forecast is not a write-off for a city trip. The advice for driving up to Park City is to pick a sunny day with nothing in the forecast rather than chance it. The city itself is "all decorated and very festive for the holidays." Our record has 24.7cm of December snow and -5.9°C nights, so the valley does get it; it just doesn't hold it.

Regulars describe two very different scenes a short drive apart: the valley floor typically green and in the 60s Fahrenheit with snow on the ground genuinely unusual, while the mountains stay cool enough to hold real snow, hardening overnight and softening into spring mush by afternoon. Our row backs both halves, 17C over 5.1C nights feeling 2C in town, with 43.4mm of rain across 4.5 days and a real 5.7cm of snow reflecting the higher-elevation total rather than anything sticking downtown. Regulars name Snowbird specifically as the resort most likely to stay open into late April, sometimes past Memorial Day, though a storm dropping over a foot of fresh snow remains a real possibility even this late in the season. The record: humidity 63 percent, 11.1 hours of sun, a 13.6 kph wind and AQI 57.

Asked about October snow, regulars give the reassuring version and the reason behind it: a storm can arrive, but the ground is still warm, so it melts off the streets quickly. Our 1.8cm for the month is that - a possibility rather than a season. Mid-October they put in the sixties by day and forties at night, and our 19.4C over 6.2C agrees, though the felt figures are 17C and 3C on very dry air, a dew point of 1.6C. The colour peaks in the canyons in the last days of September and the first week of October and holds into the second weekend, so an early-month trip catches it and a late one does not. The record: 40.8mm of rain across 3.9 days, 9.4 hours of sun and AQI 38.

Regulars call September the glorious month here - warm days in the seventies and eighties, evenings dropping to the fifties and sixties, and little rain - and our row is that description in metric: 28.5C over 13.9C with 19.4mm falling across 1.3 days. The dryness is the real signature, 50 percent humidity and a dew point of 4.4C, which is why a hot afternoon still cools hard after dark and a sweater is not optional. Fall colour runs from late September into early October, and it starts high: the canyons above the city, Alta and Brighton, turn first and are quiet at that point in the year. Snow can reach those elevations from mid-month while the valley sees none. The record: 11.1 hours of sun and AQI 41.

May in Salt Lake City is two months in one, and the local saying regulars quote is that if you do not like the weather you should wait a minute. Early May is the unpredictable half, with snow still possible at higher elevations; late May settles into mild to warm, their range running from 60 to 90F against our row's 23C average high. The advice is layers, because the swing from the morning low to the afternoon high is large and grows larger the higher you drive. That elevation is the other May warning: snow and mud can still be sitting on the upper trails, so the hiking you planned may have to wait for the melt. Our row keeps 0.5cm of snow inside the May normal. The record: 10C nights, 3.6 precipitation days carrying 31.5mm and 12.5 hours of sun.