Skip to content
WeatherTotals

Can you see the northern lights in South Dakota tonight?

Unlikely: Kp 1.33 at 2:04 PM CDT falls short of the Kp 4 or so that South Dakota's northern horizon requires.

as of

Kp now

1.33

South Dakota needs

Kp 4

Verdict

Unlikely

Sky tonight

Partly cloudy, 64% cloud

Moon tonight

14% lit, waning crescent

Nautical darkness

Darkness 8:02 PM to 6:33 AM

Kp from NOAA SWPC estimated planetary K index. The NWS ABR gridded forecast provides cloud cover for Roy Lake State Park.

At Roy Lake State Park, nautical darkness begins at 8:02 PM and holds until 6:33 AM CDT. Tonight's moon, in its waning crescent phase, shows 14 percent lit. The sun and moon positions, computed for the date and the viewing spot, supply both numbers, and no forecast plays a part.

What is Kp?

A 0-9 scale called Kp rates the current disturbance of Earth's magnetic field. Its name comes from planetarische Kennziffer, German for planetary index. Thirteen observatories worldwide take the measurements. Higher values mean the aurora reaches further south. Most of the northern US needs a Kp of 5 or higher, while northern Alaska sees it at Kp 0. Full Kp guide.

Why South Dakota needs Kp 4

Because the aurora follows the magnetic field rather than the equator, geomagnetic latitude matters more than map latitude. At South Dakota's northern edge, the reading is 54.0° geomagnetic; the oval only draws level with that latitude at about Kp 4, and the Kp number already includes roughly 5 degrees of cushion, because the high-altitude aurora hangs low on the horizon.

Where to watch from in South Dakota

All three spots in South Dakota can differ in cloud cover, so all three are worth a look. Custer State Park, Sylvan Lake looks clearest tonight, at 40% cover.

Dark sky viewing spots in South Dakota with tonight's forecast cloud cover
SpotCloud tonightClearest hourNearest town
Roy Lake State Park64% Partly cloudy9:00 PM CDTLake City
Sica Hollow State Park63% Partly cloudy2:00 AM CDTLong Hollow
Custer State Park, Sylvan Lake40% Mostly clear12:00 AM MDTHill City

South Dakota sees aurora on many nights, and Roy Lake State Park near Lake City is a good dark site. Sica Hollow State Park near Long Hollow and Custer State Park's Sylvan Lake near Hill City offer more options. Equinox peaks are strong, and dark nights run October to March.

Can the northern lights reach Rapid City and Sioux Falls tonight?

Kp each city in South Dakota needs for the northern lights, and the verdict at Kp 1.33
CityKp neededRight now
Rapid CityKp 5No chance
Sioux FallsKp 5No chance

Each city's Kp value comes from its own coordinates and geomagnetic latitude, so the further south a city is in the state, the higher the Kp it needs.

Cloud cover, averaged over tonight's viewing window for each location, comes from NWS gridded forecasts.

Was there aurora last night in South Dakota?

The night of October 6 topped out at Kp 2.33, short of the 4 South Dakota needs, so the aurora stayed out of range.

The most recent night in range was October 5, 2026, when the night's highest Kp reached 4.00.

59 nights so far in 2026 have been in range for South Dakota, against a yearly average of 63.7 across the complete years since 1994. The year's highest night Kp so far is 8.67, set on January 19, 2026.

Nights in range by year in South Dakota

Nights in range by year in South Dakota, 2015 to 2026
YearNights in rangeHighest KpPeak date
2026 2026 is not over598.67Jan 19, 2026
20251098.67Nov 11, 2025
2024579.00May 10, 2024
2023697.67Apr 23, 2023
2022776.00Jan 14, 2022
2021547.00Nov 3, 2021
2020206.00Sep 27, 2020
2019355.00Jan 4, 2019
2018536.00Mar 18, 2018
2017868.00Sep 7, 2017
20161007.00Mar 6, 2016
2015878.00Mar 17, 2015

Local time 9 pm to 3 am is the span of a night. The night's Kp is the highest among the three hour windows overlapping those hours. A night is in range when that Kp reached the threshold the state needs, which comes from where the northern edge of the state sits in geomagnetic latitude. Cloud is not in the record, so in range means the aurora was in range, not that anyone saw it. Figures are NOAA Space Weather Prediction Center daily geomagnetic data from 1994 on.

The next three days

NOAA's three-hour Kp outlook. At the highest expected value of Kp 5.67, the aurora would come into range for South Dakota.

Three-day planetary Kp forecast for South Dakota
DayLocal windowKpIn range
Oct 67 PM to 10 PM CDT00-03UT1.00No
Oct 610 PM to 1 AM CDT03-06UT1.33No
Oct 71 AM to 4 AM CDT06-09UT1.00No
Oct 74 AM to 7 AM CDT09-12UT0.67No
Oct 77 AM to 10 AM CDT12-15UT2.00No
Oct 710 AM to 1 PM CDT15-18UT2.67No
Oct 71 PM to 4 PM CDT18-21UT2.67No
Oct 74 PM to 7 PM CDT21-00UT3.00No
Oct 77 PM to 10 PM CDT00-03UT1.33No
Oct 710 PM to 1 AM CDT03-06UT1.67No
Oct 81 AM to 4 AM CDT06-09UT1.33No
Oct 84 AM to 7 AM CDT09-12UT1.67No
Oct 87 AM to 10 AM CDT12-15UT1.67No
Oct 810 AM to 1 PM CDT15-18UT1.33No
Oct 81 PM to 4 PM CDT18-21UT1.33No
Oct 84 PM to 7 PM CDT21-00UT1.33No
Oct 87 PM to 10 PM CDT00-03UT1.67No
Oct 810 PM to 1 AM CDT03-06UT5.00Yes
Oct 91 AM to 4 AM CDT06-09UT4.33Yes
Oct 94 AM to 7 AM CDT09-12UT5.67Yes
Oct 97 AM to 10 AM CDT12-15UT4.00Yes
Oct 910 AM to 1 PM CDT15-18UT3.00No
Oct 91 PM to 4 PM CDT18-21UT3.00No
Oct 94 PM to 7 PM CDT21-00UT4.00Yes

NOAA Space Weather Prediction Center three-day forecast, issued 2026 Oct 07 1230 UTC.

The next 27 days

The NOAA Space Weather Prediction Center outlook puts 6 of the next 27 days at or above Kp 4.

This Kp outlook is issued by the NOAA Space Weather Prediction Center at 2026 Oct 05 0139 UTC.

Watching from South Dakota

Compare every state, ranked right now

The NOAA Space Weather Prediction Center produces the Kp readings and aurora forecasts on this page. As US government works, they are not subject to copyright under 17 U.S.C. 105; this notice is the notice required by 17 U.S.C. 403. Mention of the center does not imply endorsement or affiliation; for attribution, see Data sources and attribution.