The year in Moab, month by month
The figures are Moab's, at 1,227 metres and next to Arches and Canyonlands: 232.9 millimetres of water a year over 61.6 days and 23.2 centimetres of snow. Where useful, they are compared with Bryce Canyon City, at 2,336 metres. The scoring crosses three things: the day's heat, the night's cold and the rain.
The parks of southern Utah are almost always visited on the same trip and with the same suitcase. It is a reasonable mistake and an expensive one, because between two of them there is a temperature difference that in Europe would mean crossing a continent.
On the same July day, the average high in Moab — the base for Arches and Canyonlands — is 37.3 degrees, and in Bryce Canyon City it is 26.6. Eleven degrees less. The average lows for the same month are 19.1 and 8.3. Again, eleven degrees.
01 Thirty-seven degrees and twenty-seven
It is worth fixing both portraits. Moab sits at 1,227 metres of altitude, its climate is classified as cold semi-arid, and it receives 232.9 millimetres of rain a year over 61.6 days. It is a textbook desert: dry, with a large daily range and brutal extremes, with records of 46 degrees and 31 below zero.
Bryce Canyon City sits at 2,336 metres and its climate is classified as humid continental. It receives 397 millimetres a year over 73 days and its annual average high is 13.4 degrees, against Moab's 22.3. Nine degrees of difference sustained all year.
And they are not distant parks on the state's scale: both are in the southern corner of Utah, within the same road itinerary. What separates them is not horizontal distance but vertical.
02 Eleven hundred metres of difference
The 1,109 metres between the two stations explain almost everything. The general rule in the atmosphere is that temperature drops about six and a half degrees per thousand metres of ascent, and here the result holds fairly faithfully.
That altitude is not accidental: it is the same staircase of rock layers that orders the parks. Zion and the Moab desert sit on the low steps, and Bryce is at the top, its rim between 2,400 and 2,700 metres and its highest point, Rainbow Point, at 2,775.
The practical consequence is direct and very useful: in Utah altitude works as air conditioning. In the middle of July, climbing to Bryce is the equivalent of travelling to another latitude, and the road does it in a few hours.
03 Ten times more snow
The most spectacular contrast is not in temperature but in snow. Moab accumulates 23.2 centimetres of snow a year, almost all in December, over 4.7 snowy days. Bryce Canyon City accumulates 222.8 centimetres: practically ten times more.
The monthly distribution is just as revealing. At Bryce, January and February each total 44.7 centimetres, March 40.4 and April still 18.8. In other words: in a park many people visit at Easter, April is still a snow month.
And the cold follows. Bryce's average January low is −12.3 degrees, with a record of −32.2. Moab's, in the same month, is −5.9. Both are cold, but one is a desert that is mild in winter and the other is a mountain.
The year's four stretches
From 17 to 19 millimetres a month, with highs of 6.4 to 11.2 degrees and lows below freezing. Moab gets 12 centimetres of snow in December; Bryce gets 44.7 in January, and there the average low is −12.3 degrees.
18, 20 and 21 millimetres over about five days each month. Highs climb from 18.1 to 28.1 degrees and lows from 2.0 to 10.4. The stretch with the best balance between day and night temperature in the low desert.
8.9, 23 and 22 millimetres, with highs of 34.4 to 37.3 degrees and a record of 46. The only stretch in which climbing to Bryce's 2,336 metres stops being an excursion and becomes a strategy.
23, 26 and 18 millimetres over five days or fewer. Highs fall from 30.9 to 13.9 degrees and lows from 12.6 to −0.9. September and October are, with April and May, the year's best months.
04 The desert summer is not a season
July and August are these parks' high season and also the worst time to walk them. In Moab, July's average high is 37.3 degrees and August's 35.5, and the records reach 46 and 43. In a landscape of bare rock without a tree, those figures feel multiplied.
On top of that comes a surprising calendar detail: August is the summer month with the most days of precipitation, 6.4, because the afternoon storms arrive. They are short, very intense and capable of turning a narrow canyon into a channel, so it pays to check the forecast before entering one.
The obvious strategy, if you travel in summer, is to use altitude. Bryce in July gives average highs of 26.6 degrees and lows of 8.3: you can walk comfortably all day and sleep under a blanket.
05 And winter is not one thing either
At the other end of the year the asymmetry reverses. Moab in winter is uncomfortable but workable: average highs of 6.4 degrees in January, 17 millimetres of water and hardly any snow. You can walk in a coat and enjoy the complete absence of people.
Bryce in winter is another matter. With 44.7 centimetres of snow a month and average lows of −12.3 degrees, many of the trails dropping into the amphitheatre become difficult and some road sections can close. In exchange, the combination of orange rock and snow is probably the state's most recognisable image.
The lesson is the same as in summer, inverted: there is no single Utah winter, there is a low-desert winter and a high-plateau winter, and there are eleven hundred metres between them.
06 How to choose the month
If you can go only once, go in May or October. In Moab, May gives average highs of 28.1 degrees and 21 millimetres over 4.8 days; October gives 23.1 degrees and 26 millimetres over 5.4 days. Both let you walk at any hour in the desert and climb to Bryce without finding it under snow.
April and September are the alternatives and work almost as well, with average highs of 22.4 and 30.9 degrees. Bear in mind that in April Bryce still accumulates 18.8 centimetres of snow a month, so the high ground can be in winter condition.
And whatever you do, pack for two climates. In April, a single day can give you a high of 22.4 degrees in Moab and a low of −4.4 at Bryce: twenty-seven degrees of range inside the same trip.
