Three hundred days a year. That is how many days of sunshine Bend receives annually — at least according to local legend.

The old saying that Bend receives 300 days of sunshine a year goes back generations and tends to be thrown around as if it were fact. We asked experts, who told us the number is likely lower. That may disappoint sun worshippers or promoters of real estate. We decided to investigate the possibility on our own. So since Jan. 1, we’ve been keeping track of the weather, documenting the varying degrees of cloudiness on a spreadsheet over the past six months.

Lesson in history

Before going over the results, it’s worth understanding just how the claim of 300 days of sunshine became attached to the city of Bend. Certainly, the assertion can be found in all manner of promotional and marketing campaigns for the city, mainly from real estate professionals and others trying to lure people (and money) over the mountains from Oregon’s often cloudy west side.

“Over 300 days of sunshine every year,” the Bend-Deschutes County Realty Board stated in a promotional listing published in The Bulletin 97 years ago. In another article in The Bulletin, published in 1912, the founder of the Bend Emblem Club was even more ambitious, boasting that Bend enjoys 320 days of sunshine.

Kelly Cannon-Miller, executive director of the Deschutes Historical Museum, said Bend was not alone in claiming to have 300 days of sunshine a year. And she believes there’s a connection to the various places that make such a claim — the arrival of the railroad.

“The idea that the West was full of sun and promise was routinely used by railroad companies in marketing campaigns,” said Cannon-Miller.

“Then multiple development companies picked up on it and recycled it, making who first coined the phrase difficult to ascertain. Safe to say, the idea came with settlers moving here who then incorporated it into Bend’s marketing as well,” Cannon-Miller said.

How much sunshine?

Even if the claim is based on little more than clever marketing schemes, there’s no denying that Bend does get plenty of sun, especially relative to cities west of the Cascades. Exactly how much sunshine can only be told in ballpark figures — not every year is the same as the last.

Some climatologists have offered estimates.

George Taylor, a former state climatologist for Oregon, said in his 1999 book “Climate of Oregon” that Bend receives around 186 days of sun a year when averaged over a full day from midnight to midnight. His number is based on data from a ceilometer, which measures cloud cover with a laser and is usually used at airports.

Oregon’s current state climatologist, Larry O’Neil, made calculations using a slightly different time frame and came up with 202 sunny or mostly sunny days in Bend. His data is based on a meteorological reanalysis of historic and archived data.

Running our own test

While analysis utilizing the latest technology puts the number of sunny days at yearly totals far less than 300, our analysis with more rudimentary observations indicates still different numbers.

We set up a spreadsheet with five categories to record the amount of cloud cover since Jan. 1. A category was checked for each day. Notes were made to describe weather conditions.

With no ceilometer available to The Bulletin, our calculations started with simple daily observations. More recently, our calculations were informed by weather apps that assign a percentage to the amount of cloud cover in the sky. Over the weeks and months, our descriptions of cloud advanced in specificity — cumulus, stratus, cirrus and the odd cumulonimbus found their way into the spreadsheet.

Fickle skies

Central Oregon’s fickle weather proved difficult to assign a single adjective to a day. Overcast mornings sometimes turned sunny in the afternoon. And sunny mornings occasionally clouded over during the course of a day. These days were a coin toss and usually ended up in the 50/50 category, indicating a day of half sun and half cloud.

On a few days this year, the weather changed by the hour, with sun and cloud changing frequently, with occasional snowstorms in between — one of those “four seasons in one day” events that occur in Bend from time to time, especially in March. Assigning a “mixed conditions” label was often the best we could do. By our calculations, this type of weather pattern occurred at least twice in February, nine days in March, three days in April and four days in May.

Finally, it’s sometimes challenging to discount those “partly cloudy” conditions when the sky may be filled with majestic cumulus clouds that look like enormous cotton balls floating past. Calling this kind of day “cloudy” didn’t feel right in our calculations, so we created a pie chart that includes slices of varying cloudiness.

Given the subjectiveness of declaring a day “sunny” versus “cloudy,” there may never be a complete answer to this question.

Nevertheless, the results of our observations are as follows for the first six months of 2024:

• Mostly sunny: 74 days

• Partly cloudy: 24 days

• 50/50 sun and cloud: 31 days

• Mostly cloudy: 20 days

• Overcast: 33 days.

Considering the optimistic estimate, which includes the first three categories, Bend had 129 “days of sunshine” in the first six months, putting the city on pace for 256 days over a year (seasonal variations notwithstanding). O’Neil said using a climate reanalysis dataset “isn’t perfect,” so it’s not surprising that an observation-based method is tracking differently than one based on technical equipment.

We’re not sure if this projection, should it prove accurate, will resolve the flap over Bend’s claim to having 300 days of sunshine a year. But even if Bend falls short of the magical number of 300 days, most will agree the weather here is pretty darn good.

A report with the final numbers for 2024 will be available in January.