Missoula, MT · magnetic latitude 53.7°
Northern lights in Missoula: tonight’s chance
Missoula sits where five valleys meet; getting above the valley floor is half the work on a storm night.
Tonight at Missoula, MT
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Reading the SWPC Kp forecast and the cloud forecast…
| Kp forecast during the dark hours | not yet forecast |
|---|---|
| Kp needed here | 6.2 (G2 moderate) |
| Cloud cover in the dark hours | loading |
| Dark sky (Sun 18° down) | 8:33 PM to 6:11 AM MDT |
| Moon | 13% lit |
| Right now, OVATION (30 to 90 min) | loading or unavailable |
| Magnetic latitude (AACGM) | 53.7° |
Hour by hour, MDT
7 PM
Kp –
– ☁
No
8 PM
Kp –
– ☁
No
9 PM
Kp –
– ☁
No
10 PM
Kp –
– ☁
No
11 PM
Kp –
– ☁
No
12 AM
Kp –
– ☁
No
1 AM
Kp –
– ☁
No
2 AM
Kp –
– ☁
No
3 AM
Kp –
– ☁
No
4 AM
Kp –
– ☁
No
5 AM
Kp –
– ☁
No
6 AM
Kp –
– ☁
No
Rules checked · Built by Radif Partners · How the answer works
- Kp to see it from Missoula
- 6.2
- Storm level needed
- G2 (Moderate)
- Kp for aurora overhead
- 6.2
- Most clear dark hours
- September
Missoula needs a planetary Kp of about 6.2 to see the northern lights, a G2 (Moderate) storm on the NOAA scale. The city sits at 53.7 degrees magnetic latitude in the AACGM model, about the same as Spokane and Billings, and the aurora reaches overhead around Kp 6.2. Its setting is the complication: the city fills the floor of a basin ringed by mountains, so the low northern sky, where a storm at the edge of the range appears, is hidden from town. Clouds follow a valley pattern too, with the NASA POWER cloud amount at 32% in July and 78% in March, when inversions trap low cloud. By clear dark hours the best months are September, August and October, with 8.0 hours of full darkness on the 15th of the first.
A city at the bottom of a bowl
Missoula grew where the Clark Fork, the Bitterroot and the Blackfoot rivers meet, in a basin that once held Glacial Lake Missoula. The mountains around it are what make the city attractive and what make aurora watching harder. A display at Kp 6.2 rises only a few degrees above the true horizon, and from most streets the ridges to the north are higher than that. On a strong storm the aurora climbs well above them, but the nights at the threshold are the common ones, and they reward the people who drive.
The valleys leading north are the natural escape. Highway 93 climbs out of town toward the Mission Valley and Flathead Lake, where the land opens and the northern sky drops close to a flat horizon. The run north also gains a little latitude: Kalispell needs about Kp 5.6.
How dark, how clear: one town, one month
Hours of full darkness on the 15th
5.8 h
| Dark sky | 10:47 PM to 4:34 AM |
| Including nautical twilight | 7.3 h |
| Mean cloud amount (NASA POWER) | 37% |
| Clear dark hours on an average night | 3.7 h |
Computed for 2027; the hours move by a few minutes from one year to the next.
Inversions and smoke
In winter, cold air drains into the basin on calm nights and stays under warmer air above, holding haze, fog and low cloud on the valley floor. The tool reads the National Weather Service sky cover for the coordinates you give, so try a point on the ridges or up the valley when town is socked in. In late summer the problem can be wildfire smoke, which dims a faint aurora the way thin cloud does; the cloud forecast does not measure it, so judge by how many stars you see.
A university town's habits
Missoula is a university town, and a storm night tends to send a stream of cars up the same few roads at the same hour. Two habits help. Leave earlier than the forecast peak, because the SWPC blocks are three hours long and the burst of activity inside a block can come at its start. And let your eyes adapt for twenty minutes away from headlights before deciding there is nothing there: at the threshold, the aurora often looks like a grey band that the camera reveals as green. The phone guide explains why.
Compared with the rest of Montana
Missoula's threshold is close to that of Billings, 6.3, and well behind the Hi-Line towns. For the full ladder of Montana towns see the table below and the Montana page; for the neighboring Inland Northwest, the Spokane page.
Kp needed around Missoula
| Town | Magnetic latitude | Kp to see it | Kp overhead | Storm level |
|---|---|---|---|---|
| Havre | 56.0° | 5.0 | 5.0 | G1 (Minor) |
| Kalispell | 54.9° | 5.6 | 5.6 | G1 (Minor) |
| Great Falls | 54.7° | 5.6 | 5.6 | G1 (Minor) |
| Missoula | 53.7° | 6.2 | 6.2 | G2 (Moderate) |
| Billings | 53.5° | 6.3 | 6.3 | G2 (Moderate) |
| Bozeman | 53.0° | 6.4 | 6.5 | G2 (Moderate) |
Darkness and clouds by month in Missoula
| Month | Dark hours | Dark sky, 15th | Mean cloud | Clear dark hours |
|---|---|---|---|---|
| January | 11.4 h | 7:02 PM to 6:28 AM | 76% | 2.7 h |
| February | 10.2 h | 7:42 PM to 5:57 AM | 77% | 2.4 h |
| March | 8.7 h | 9:23 PM to 6:05 AM | 78% | 1.9 h |
| April | 6.6 h | 10:17 PM to 4:53 AM | 74% | 1.8 h |
| May | 4.3 h | 11:23 PM to 3:40 AM | 69% | 1.3 h |
| June | 2.4 h | 12:26 AM to 2:47 AM | 60% | 0.9 h |
| July | 3.4 h | 12:00 AM to 3:23 AM | 32% | 2.3 h |
| August | 5.8 h | 10:47 PM to 4:34 AM | 37% | 3.7 h |
| September | 8.0 h | 9:32 PM to 5:30 AM | 48% | 4.1 h |
| October | 9.7 h | 8:29 PM to 6:14 AM | 66% | 3.4 h |
| November | 11.1 h | 6:47 PM to 5:54 AM | 77% | 2.6 h |
| December | 11.8 h | 6:38 PM to 6:24 AM | 78% | 2.6 h |