Sioux Falls, SD · magnetic latitude 52.6°
Northern lights in Sioux Falls: tonight’s chance
South Dakota’s largest city needs a moderate storm, and a short drive north onto open farmland.
Tonight at Sioux Falls, SD
…
Reading the SWPC Kp forecast and the cloud forecast…
| Kp forecast during the dark hours | not yet forecast |
|---|---|
| Kp needed here | 6.5 (G2 moderate) |
| Cloud cover in the dark hours | loading |
| Dark sky (Sun 18° down) | 8:21 PM to 6:04 AM CDT |
| Moon | 13% lit |
| Right now, OVATION (30 to 90 min) | loading or unavailable |
| Magnetic latitude (AACGM) | 52.6° |
Hour by hour, CDT
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 Sioux Falls
- 6.5
- Storm level needed
- G2 (Moderate)
- Kp for aurora overhead
- 6.7
- Most clear dark hours
- November
Sioux Falls needs a planetary Kp of about 6.5 to see the northern lights, a G2 (Moderate) storm on the NOAA scale. In the AACGM model the city lies at 52.6 degrees magnetic latitude, the lowest of the South Dakota towns compared on this site, while Aberdeen, about 200 miles north, needs 5.8. The aurora reaches the zenith over Sioux Falls only around Kp 6.7, a strong G3 storm. Most sightings here are therefore of a glow low in the north, which makes the city's own light the main local enemy. Sioux Falls' NASA POWER cloud amount ranges from 44% in July to 67% in December. Taking dark hours into account, the months with the most clear dark sky are November, September and October.
A southern corner of the aurora map
Sioux Falls sits in the far southeastern corner of South Dakota, where the state meets Minnesota and Iowa, and its magnetic latitude is close to that of Madison or Grand Rapids. It needs about 0.6 Kp more than Aberdeen. That gap is the difference between storms that arrive several times a year near solar maximum and storms that come a few times a year, and it is why a drive north is the standard advice for Sioux Falls residents on a storm night: an hour up Interstate 29 toward Watertown buys part of that gap and leaves the city glow behind.
How dark, how clear: one town, one month
Hours of full darkness on the 15th
9.8 h
| Dark sky | 8:18 PM to 6:06 AM |
| Including nautical twilight | 10.9 h |
| Mean cloud amount (NASA POWER) | 54% |
| Clear dark hours on an average night | 4.5 h |
Computed for 2027; the hours move by a few minutes from one year to the next.
The Big Sioux valley and the farmland
The Big Sioux River runs through the city and north along a shallow valley lined with farms. The land is gently rolling, so a rise a few miles out of town gives a long view north over fields, with few lights other than farmsteads and grain elevators. Light from the city spreads into the sky as a dome visible from far away; on a storm night, standing with that dome behind you to the south is what matters. Snow cover in winter brightens the ground under any light and makes the dome larger, one more reason to drive farther in January than in October.
Living with a moderate threshold
A threshold of Kp 6.5 changes how to use a forecast. The quiet and active nights of most of the year, Kp 2 to 4, are not worth a trip from Sioux Falls, however clear the sky. What is worth acting on is an SWPC watch for G2 or stronger, followed by a confirmation on the night itself: the OVATION line of the tool turning upward, or the current Kp estimate climbing past 6. That keeps the number of wasted drives low and catches the nights that matter.
Weather and timing
The southeast of the state gets more moisture than the west, with summer storms and winter systems from the south. Clear Arctic air behind a cold front gives the most reliable winter nights. On December 15, full darkness runs from 6:34 PM to 6:09 AM; on June 15 it lasts only 3.9 hours. The three-night forecast lines up the SWPC blocks with those hours, and the South Dakota page compares the rest of the state.
Kp needed around Sioux Falls
| Town | Magnetic latitude | Kp to see it | Kp overhead | Storm level |
|---|---|---|---|---|
| Aberdeen | 54.3° | 5.8 | 5.8 | G2 (Moderate) |
| Watertown | 53.9° | 6.0 | 6.0 | G2 (Moderate) |
| Pierre | 53.1° | 6.4 | 6.4 | G2 (Moderate) |
| Sioux Falls | 52.6° | 6.5 | 6.7 | G2 (Moderate) |
| Rapid City | 52.5° | 6.5 | 6.7 | G2 (Moderate) |
Darkness and clouds by month in Sioux Falls
| Month | Dark hours | Dark sky, 15th | Mean cloud | Clear dark hours |
|---|---|---|---|---|
| January | 11.3 h | 6:57 PM to 6:15 AM | 64% | 4.0 h |
| February | 10.2 h | 7:33 PM to 5:48 AM | 63% | 3.8 h |
| March | 8.9 h | 9:08 PM to 6:01 AM | 66% | 3.0 h |
| April | 7.1 h | 9:54 PM to 4:58 AM | 60% | 2.8 h |
| May | 5.2 h | 10:47 PM to 3:58 AM | 62% | 2.0 h |
| June | 3.9 h | 11:31 PM to 3:23 AM | 55% | 1.8 h |
| July | 4.5 h | 11:17 PM to 3:48 AM | 44% | 2.5 h |
| August | 6.4 h | 10:20 PM to 4:42 AM | 47% | 3.3 h |
| September | 8.2 h | 9:14 PM to 5:29 AM | 44% | 4.6 h |
| October | 9.8 h | 8:18 PM to 6:06 AM | 54% | 4.5 h |
| November | 11.0 h | 6:41 PM to 5:42 AM | 58% | 4.6 h |
| December | 11.6 h | 6:34 PM to 6:09 AM | 67% | 3.9 h |