Aurora Forecast and Prediction for Greater Sudbury, Ontario

Aurora Visibility0Poor

Kp: 0.33 | Bz: -0.9

Prediction0Little to None

Current Conditions (as of 7:19 PM EDT): Little to no aurora activity in Greater Sudbury. Geomagnetic conditions are quiet. Overcast skies will likely block any aurora view.

Predicted Outlook (7:19 PM – 7:29 AM EDT): Little to no aurora activity expected currently. Geomagnetic conditions are quiet.

Best Viewing Window: 7:19 PM – 7:29 AM EDT (12h 10m) · peak hours typically 11:14 PM – 3:14 AM

Bz -0.9 nT Aurora None Nautical Twilight Overcast · 88% Prediction 0 · Little to None Full Moon 100% Color Key

Good Viewing Locations Nearby A.Y. Jackson Lookout 35 km Killarney Provincial Park 100 km

Space Weather Now

Kp (now)

0.33

Forecast Kp (tonight)

Bz (nT)

-0.9

HPI

8 Minimal · 15 GW

Dst (nT)

Density (p/cc)

3.9

Speed (km/s)

342

Sky / Darkness

Overcast Nautical Twilight

Sunspot Number

Timing: Now

Webcam

No aurora cams nearby. Center on nearest camera (768 km away).

Browse other webcams on Windy

3-Day Forecast for Greater Sudbury, Ontario

Tonight's forecast peaks at Kp 3, short of the roughly Kp 4 the aurora usually needs to be seen from Greater Sudbury.

Oct 25

Global: Quiet Greater Sudbury: Not expected

Kp 3 is short of the roughly Kp 4 the aurora needs to clear the northern horizon from Greater Sudbury.

Global: Quiet planetary conditions expected - aurora mostly confined to the far north.

Best time to look up: 8:00 PM–11:00 PM EDT

30% chance of elevated activity · Kp 3 during viewing window

Oct 26

Global: Quiet Greater Sudbury: Not expected

Kp 1.7 is short of the roughly Kp 4 the aurora needs to clear the northern horizon from Greater Sudbury.

Global: Quiet planetary conditions expected - aurora mostly confined to the far north.

Best time to look up: 11:00 PM–2:00 AM EDT

10% chance of elevated activity · Kp 1.67 during viewing window

Oct 27

Global: Quiet Greater Sudbury: Not expected

Kp 1.7 is short of the roughly Kp 4 the aurora needs to clear the northern horizon from Greater Sudbury.

Global: Quiet planetary conditions expected - aurora mostly confined to the far north.

Best time to look up: 11:00 PM–2:00 AM EDT

10% chance of elevated activity · Kp 1.67 during viewing window

Quiet across all 3 days - low likelihood of an aurora display.

Aurora Oval & Satellite & Sun

Aurora Probability

LowHigh

Interactive Aurora Globe

Full-size Aurora Globe

Satellite View

Choose your view:

National Weather Service

Sunspots

Current sunspot number: 22

SOHO

Coronal Mass Ejections

Space Weather Prediction Center

Aurora Photography by Todd Salat

Original prints from Todd Salat's collection.

White Satin - aurora borealis photograph taken at Kenai Mountains by Todd Salat

Alaska Gold

Talkeetna, Alaska · 2009

See the full gallery Prints and pricing

Nerd Mode

Solar Wind & IMF (GSM)

Bt: 3.2 nT
Bx: -0.1 nT
By: 3.1 nT
Bz: -0.9 nT
Clock Angle θ: -16.2°
Cone Angle φ: 92.8°
Speed: 342 km/s
Density: 3.9 p/cc

Real-time solar wind and interplanetary magnetic field, in geocentric solar magnetospheric (GSM) coordinates - the values the prediction model actually runs on.

IMF Detail (GSE) & Source

Bx: -0.1 nT
By: 3.2 nT
Bz: -0.3 nT
θ Angle: -5.4°
φ Angle: 92.6°
Satellite: SOLAR-1
Data Quality: Good
Reading Time: Oct 25, 7:16 PM EDT

The same magnetic field reading in geocentric solar ecliptic (GSE) coordinates, plus which satellite it came from and how fresh it is.

Geomagnetic Indices

Kp (now): 0.33
Dst: 18 nT
HPI: 8 GW
Sunspot Number: 22

Headline storm-activity indices - Kp (planetary), Dst (ring current), HPI (hemispheric power), and today's sunspot count.

Aurora Model

Ovation Value: 0
Ovation Label: None
Model Data Time: Oct 25, 8:27 PM EDT
Ovation Data: Live

NOAA's OVATION Prime output - how far south the aurora oval is likely to extend right now.

Scores & Ratings

Aurora Visibility: 0 · Poor
Aurora Visibility (w/ Moon): 0 · Poor
Prediction Score: 0 · Little to None

This page's scores side by side - Aurora Visibility (activity adjusted for cloud and darkness), the same with a moonlight factor (switched off, so identical), and the Prediction score for right now.

Sky & Location

Cloud Cover: 88% · Overcast
Clouds, Next Dark Window: 99% · Overcast · ×0.05
Aurora Visibility Tonight: 0 · Poor (Outlook Tonight 1 × cloud 0.05)
Solar Elevation: -11° · Nautical Twilight
Moon Phase: Full Moon
Moon Illumination: 100%
Moon Altitude: 16.9° · Up
Latitude: 46.49
Longitude: -80.99001
Geomagnetic Latitude: 55.7°
Horizon Threshold: Kp 4
Overhead Threshold: Kp 6

Local sky and moon conditions - what actually turns the raw aurora score into a real visibility score for this spot.

Prediction Model Inputs

Bz Persistence (60min): 1.1 nT
Newell Coupling: 2861
Latitude Gate: 0.00 now · 0.03 tonight (horizon Kp 4.3, verdict rounds to Kp 4)
Dynamic Pressure: 0.8 nPa
Storm Watch (CME): —
Watch Predicted Kp: —

The individual weighted inputs - Bz persistence, coupling, pressure, CME timing - that combine into the Prediction score.

Timing & Signal Agreement

Timing: Now
Signal Agreement: High (7 of 7)
: Do the live inputs point the same way as the score? A score lifted by this city's own Kp can read Low while the solar wind is calm.
L1 Delay: ~73 min
Magnetic Midnight: 1:14 AM (peak hours 11:14 PM – 3:14 AM)
Best Viewing Window: 7:19 PM – 7:29 AM EDT (12h 10m)

How soon a solar wind change reaches Earth, whether the model's inputs agree with each other, and today's best window to actually look up.

3-Day Kp Forecast

UT slot (EDT)	Oct 26 UT	Oct 27 UT	Oct 28 UT
00–03 UT (8:00 PM–11:00 PM)	3	1.67	1.33
03–06 UT (11:00 PM–2:00 AM)	2	1.33	1.33
06–09 UT (2:00 AM–5:00 AM)	2	1.33	1.67
09–12 UT (5:00 AM–8:00 AM)	2	1.33	1.33
12–15 UT (8:00 AM–11:00 AM)	2	1.33	1.33
15–18 UT (11:00 AM–2:00 PM)	2	1.33	1.33
18–21 UT (2:00 PM–5:00 PM)	2	1.67	1.67
21–00 UT (5:00 PM–8:00 PM)	2.33	1.67	1.67
Max	3	1.67	1.67
Ap Index	8	5	5

Columns are NOAA's UT days, so in EDT a column's first rows fall on the previous local evening.

Max Kp forecast 3 or below for all 3 days - low likelihood of an aurora display.

Storm Probability

Level	Oct 26 UT	Oct 27 UT	Oct 28 UT
Active	30%	10%	10%
Minor storm	5%	1%	1%
Moderate storm	1%	1%	1%
Strong-Extreme storm	1%	1%	1%

NOAA SWPC's official 3-day Kp forecast and geomagnetic storm probability - an independent second opinion alongside this page's own real-time model.

Planetary K-index

Oct 22

Oct 23

Oct 24

Oct 25

Now

Oct 26

Oct 27

Oct 28

Quiet (Kp 0-3) Unsettled (Kp 4) Minor-Moderate Storm (Kp 5-6) Strong+ Storm (Kp 7-9) Forecast (hatched)

Interplanetary Magnetic Field Bz-0.8 nT now

Southward (negative) Bz favors aurora. Observed data only, no forecast product exists for Bz.

Total IMF Field Bt3 nT now

Total interplanetary magnetic field strength - the ceiling on how negative Bz can go. A rising Bt alongside a still-fluctuating Bz often leads a stronger southward turn. Observed data only, no forecast product exists for Bt.

Global Storm Trend11 global now

Global (hemisphere-wide, not this city) prediction score over the last 24 hours, logged every 5 minutes - may differ from the Prediction ring above, which is specific to this location and time of night. Red from 60 (Strong), yellow from 40 (Moderate), teal below - the same cutoffs as the Prediction ring. Dashed line is the overall trend.

Dst History18 nT now

Kyoto Dst geomagnetic storm index over the last 24 hours. Negative = ring-current energy stored = an active storm, not just predicted. Red below −50nT, yellow −20 to −50nT, teal above −20nT.

Solar Wind Speed & Pressure

Speed: 347 km/s now Pressure: 0.7 nPa now

Each line is scaled independently to its own 24h range (different units) - watch the shape, not a shared axis. A rising speed line or a pressure spike can signal an incoming stream or shock before Bz/Dst move.

24-hour trend charts for the values above, so you can see whether conditions are building or fading.

Nerd Mode: See what’s really driving the score. Live solar wind, Bz, Kp, Dst, CME timing, and more. Data comes from NOAA SWPC and the Kyoto WDC, with a few metrics calculated here from the raw data. Live data refreshes every minute; trend charts every five.

Aurora Forecasts for Nearby Cities

Checking conditions somewhere else tonight? These are the closest cities with their own northern lights prediction.

North Bay 118 km
Timmins 221 km
Rouyn-Noranda 244 km
Alpena 247 km
Sault Ste. Marie 256 km
Val-d'Or 300 km
Vaughan 317 km
Markham 321 km

Debug / Test Data

UTC: 2026-10-25 23:19:59

Variable	Value
Geo
locale (GET)	sudbury
pred_city	Greater Sudbury
pred_region	Ontario
pred_lat	46.49 46.49° N
pred_lon	-80.99001 80.99001° W
pred_tz	America/Toronto
Cloud Cover (Open-Meteo)
cloud_pct	88%
cloud_cover	overcast
cloud_mult	0.05 (5%)
Sky Darkness
dark_elev	-10.98°
dark_label	Nautical Twilight
dark_mult	0.50 (50%)
Space Weather
cKp (current)	0.33
bz (nT)	-0.9
speed (km/s)	342
day1_max Kp	3
day2_max Kp	1.67
day3_max Kp	1.67
Aurora Score 0–4 None · 5–19 Weak · 20–49 Nearby · 50–100 Overhead
ovation_val	0 (None)
ovation_time	2026-10-26T00:27:00Z
space_score	0
Space Weather
bz_score	9%
bz_bar	54.5% (visual)
kp_score	4.7%
fcst_score	42.9%
Visibility Score 0.15×Ovation + 0.55×Bz + 0.30×Kp
activity_score	0
Aurora Visibility Visibility Score × cloud × darkness
× cloud_mult	0.05 (Overcast)
× dark_mult	0.50 (Nautical Twilight)
aurora_score	0 (Poor)
Aurora Visibility Tonight Outlook Tonight × cloud (dark window) × 1.0
pred_score_tonight	1 (Little to None)
× cloud_mult_tonight	0.05 (Overcast 99%)
aurora_score_tonight	0 (Poor)
Cache Freshness * = per-request, no cron
Kp Index _kps/	fresh 59s / 60s
Bz / RTSW outlook/	fresh 48s / 60s
Solar Wind outlook/	fresh 47s / 60s
Sunspots _kps/	fresh 20.6h / 24h
Ovation Aurora outlook/	fresh 59s / 5m
3-Day Geomag ^* outlook/	fresh 19m / 1h
GeoIP DB geoip/	fresh 15.7h / 168h
geo (newest) ^* outlook/geo/	fresh 0s / 24h
wx (newest) ^* outlook/wx/	fresh 1s / 20m
Image Cache /_files/_dynamic/_images/ · cron every 15m
Ovation North	fresh 5m / 15m
Ovation South	fresh 5m / 15m
Sat - Alaska	fresh 5m / 15m
Sat - N. America	fresh 5m / 15m
Sat - N. Atlantic	fresh 5m / 15m
Sat - Europe	fresh 5m / 15m
Sat - Australia	stale 5.3h / 15m
Sat - S. America	fresh 5m / 15m

Legend

Visibility Rating (aurora_score /100)
Poor	0–29	Little chance of seeing aurora
Fair	30–49	Possible under ideal conditions
Good	50–69	Good chance if skies clear
Excellent	70–100	Strong aurora likely visible

Ovation Label (0–100 scale)
None	0–4	No aurora activity at location
Weak	5–19	Faint aurora, auroral oval nearby
Nearby	20–49	Aurora active, oval edge overhead
Overhead	50–100	Aurora directly overhead

Cloud Cover Multiplier (cloud_pct %)
Clear	0–25%	× 1.00
Partly Cloudy	26–50%	× 0.85
Mostly Cloudy	51–85%	× 0.50
Overcast	86–100%	× 0.05
Unknown	—	× 0.60

Label	Elev.	Mult	Setting	Rising
Daytime	≥ 3°	× 0.00	Sun above horizon. Check back after sunset.	Sun well above horizon. Aurora viewing is over.
Appr. Civil	0–3°	× 0.00	Sunset imminent. Watch for aurora soon.	Approaching sunrise. Aurora window closing.
Civil Twilight	−4–0°	× 0.10	Too bright yet. Darkness improving.	Brightening. Last chance to catch aurora.
Appr. Nautical	−6–−4°	× 0.10	Sky darkening. Faint aurora may be visible.	Sky brightening. Window narrowing.
Nautical Twilight	−12–−6°	× 0.50	Sky darkening. Bright aurora may be visible.
Astronomical Twilight	−18–−12°	× 0.85	Near-dark sky. Good aurora viewing conditions.
Dark Night	< −18°	× 1.00	Full darkness. Optimal aurora viewing.

Debug output - remove before production

Related Northern Lights Pages

Aurora Forecast and Prediction for Greater Sudbury, Ontario

Space Weather Now

Webcam

3-Day Forecast for Greater Sudbury, Ontario

Oct 25

Oct 26

Oct 27

Aurora Oval & Satellite & Sun

Interactive Aurora Globe

Satellite View

Sunspots

Coronal Mass Ejections

Aurora Photography by Todd Salat

White Satin

AK Caboose

Alaska Gold

Nerd Mode

Solar Wind & IMF (GSM)

IMF Detail (GSE) & Source

Geomagnetic Indices

Aurora Model

Scores & Ratings

Sky & Location

Prediction Model Inputs

Timing & Signal Agreement

3-Day Kp Forecast

Storm Probability

Planetary K-index

Interplanetary Magnetic Field Bz-0.8 nT now

Total IMF Field Bt3 nT now

Global Storm Trend11 global now

Dst History18 nT now

Solar Wind Speed & Pressure

Aurora Forecasts for Nearby Cities

Debug Panel ▾

Debug / Test Data

Legend

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