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Can you see the northern lights in Wisconsin tonight?

Unlikely: Kp 1.33 at 4:21 PM CDT falls short of the Kp 3 or so that Wisconsin's northern horizon requires.

as of

Kp now

1.33

Wisconsin needs

Kp 3

Verdict

Unlikely

Sky tonight

Clear, 15% cloud

Moon tonight

40% lit, last quarter

Nautical darkness

Darkness 7:41 PM to 6:01 AM

Kp from NOAA SWPC estimated planetary K index. The NWS DLH gridded forecast provides cloud cover for Copper Falls State Park.

At Copper Falls State Park, nautical darkness begins at 7:41 PM and holds until 6:01 AM CDT. Tonight's moon, in its last quarter phase, shows 40 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 Wisconsin needs Kp 3

Because the aurora follows the magnetic field rather than the equator, geomagnetic latitude matters more than map latitude. At Wisconsin's northern edge, the reading is 55.9° geomagnetic; the oval only draws level with that latitude at about Kp 3, 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 Wisconsin

All three spots in Wisconsin can differ in cloud cover, so all three are worth a look. Newport State Park, Ellison Bay looks clearest tonight, at 4% cover.

Dark sky viewing spots in Wisconsin with tonight's forecast cloud cover
SpotCloud tonightClearest hourNearest town
Copper Falls State Park15% Clear10:00 PM CDTMellen
Newport State Park, Ellison Bay4% Clear12:00 AM CDTEllison Bay
Big Bay State Park, Madeline Island18% Clear9:00 PM CDTBayfield

Wisconsin's Copper Falls State Park near Mellen sees aurora on many nights, with equinox peaks. Newport State Park near Ellison Bay and Big Bay State Park near Bayfield on Madeline Island are other northern options. This area sits close to Lake Superior. The dark-night season runs October to March. Aurora can appear overhead.

Can the northern lights reach Green Bay, Madison and Milwaukee tonight?

Kp each city in Wisconsin needs for the northern lights, and the verdict at Kp 1.33
CityKp neededRight now
Green BayKp 4Unlikely
MadisonKp 5No chance
MilwaukeeKp 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 Wisconsin?

The night of October 3 reached Kp 3.00, at or above the 3 that Wisconsin needs, so the aurora was in range.

The most recent night in range was October 3, 2026, when the night's highest Kp reached 3.00.

121 nights so far in 2026 have been in range for Wisconsin, against a yearly average of 156.9 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 Wisconsin

Nights in range by year in Wisconsin, 2015 to 2026
YearNights in rangeHighest KpPeak date
2026 2026 is not over1218.67Jan 19, 2026
20252178.67Nov 11, 2025
20241429.00May 10, 2024
20231437.67Apr 23, 2023
20221916.00Jan 14, 2022
20211317.00Nov 3, 2021
2020946.00Sep 27, 2020
20191095.00Jan 4, 2019
20181156.00Mar 18, 2018
20171798.00Sep 7, 2017
20161927.00Mar 6, 2016
20152028.00Mar 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 5.00, the aurora would come into range for Wisconsin.

Three-day planetary Kp forecast for Wisconsin
DayLocal windowKpIn range
Oct 37 PM to 10 PM CDT00-03UT3.00Yes
Oct 310 PM to 1 AM CDT03-06UT3.33Yes
Oct 41 AM to 4 AM CDT06-09UT4.33Yes
Oct 44 AM to 7 AM CDT09-12UT5.00Yes
Oct 47 AM to 10 AM CDT12-15UT4.00Yes
Oct 410 AM to 1 PM CDT15-18UT3.67Yes
Oct 41 PM to 4 PM CDT18-21UT4.67Yes
Oct 44 PM to 7 PM CDT21-00UT3.00Yes
Oct 47 PM to 10 PM CDT00-03UT3.33Yes
Oct 410 PM to 1 AM CDT03-06UT4.33Yes
Oct 51 AM to 4 AM CDT06-09UT3.33Yes
Oct 57 AM to 10 AM CDT12-15UT2.67No
Oct 510 AM to 1 PM CDT15-18UT1.67No
Oct 54 PM to 7 PM CDT21-00UT3.00Yes
Oct 57 PM to 10 PM CDT00-03UT3.33Yes
Oct 510 PM to 1 AM CDT03-06UT3.67Yes
Oct 61 AM to 4 AM CDT06-09UT3.00Yes
Oct 64 AM to 7 AM CDT09-12UT3.00Yes
Oct 67 AM to 10 AM CDT12-15UT2.33No
Oct 610 AM to 1 PM CDT15-18UT2.00No
Oct 61 PM to 4 PM CDT18-21UT2.00No
Oct 64 PM to 7 PM CDT21-00UT1.67No

NOAA Space Weather Prediction Center three-day forecast, issued 2026 Oct 04 1230 UTC.

The next 27 days

The NOAA Space Weather Prediction Center outlook puts 13 of the next 27 days at or above Kp 3.

This Kp outlook is issued by the NOAA Space Weather Prediction Center at 2026 Sep 28 0221 UTC.

Watching from Wisconsin

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.