YTD.

A few years ago for my birthday Laura got me a rain gauge, a max/min thermometer, and a weather diary; once I made a snowstake and sunk it into the back yard I had myself a nice little weather station.

Most stations report data for the calendar year (Jan. 1-Dec. 31) or the water year (Oct. 1-Sept. 30). My data year is one of convenience starting when I got the instrumentation – Nov. 1 – and running to Oct. 31.

A detailed look at a year’s worth of weather in Missoula (3205 feet) shows a couple of interesting things. One is that, true to its nickname “Garden City”, the weather in Missoula actually is quite mild – at least when compared to the rest of Montana. Last year our high temperature was 100, and while I did not note the low, I believe it was 2. Just 100 air miles east of here that range would probably be closer to 105 to -20. Also interesting is the fact that while Missoula does not get a lot of precipitation, there is a lot of precipitating going on. I recorded at least .01 inches of precipitation on 100 days last weather year (I did some educated guessing on the days I was not here). That’s a lot, but in total we had just 11.27 inches of precipitation (rain and snow water equivalent) – which makes Missoula a desert by most counts. Because some days we have rain and snow in the same 24-hour period, and because I am lazy, the total precipitation counts below include both rain and snow – if I was dedicated to this I would tally rain and snow and rain/snow. In any case, you can see we get a lot of days of a skiff of snow or a few drops of rain, and very few days at all of long deluges.

Since I tally my data off-kilter it’s hard to compare it to the official weather station at the airport, but I do think I can generalize to say that our proximity adjacent to the mountains and nearish to Pattee Canyon’s mouth results in a tad more snow and a bit more precipitation.

So why is Missoula so “dry”? The answer I get is that the biggest storms to roll across Northwest Montana pound the mountaintops but leave north-south oriented valleys shadowed.

Anyway, here’s a rundown (larger amount categories include the smaller amounts, so 30 days of >.1" are included in the 100 days of >.01"):

Total precip: 11.27 inches

Total snow: 45.3 inches

Days of:

Precip >.01”: 100

Precip >.1”: 30

Precip >1”: 0

Snow trace: 71

Snow >1”: 10

Snow>6”: 2

Days with thunder: 3

Days with blizzard conditions: 1

Days with freezing rain: 3

Last frost: June 8

First frost: (actually I forgot to record this but I think it was) Sept. 22

Growing season: 107 days