Space Weather Alerts

Space Weather Message Code: ALTK04
Serial Number: 2614
Issue Time: 2025 Dec 07 0601 UTC

ALERT: Geomagnetic K-index of 4
 Threshold Reached: 2025 Dec 07 0559 UTC
Synoptic Period: 0300-0600 UTC
 
Active Warning: Yes

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

Space Weather Message Code: WATA50
Serial Number: 94
Issue Time: 2025 Dec 07 0443 UTC

WATCH: Geomagnetic Storm Category G3 Predicted

Highest Storm Level Predicted by Day:
Dec 08:  G1 (Minor)   Dec 09:  G3 (Strong)   Dec 10:  G1 (Minor)

THIS SUPERSEDES ANY/ALL PRIOR WATCHES IN EFFECT

Comment: Watches for G3 (Strong) on 09 Dec and G1 (Minor) on 10 Dec are in anticipation of CME arrival from the M8 flare at 06/2039 UTC.

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 50 degrees Geomagnetic Latitude.
Induced Currents - Power system voltage irregularities possible, false alarms may be triggered on some protection devices.
Spacecraft - Systems may experience surface charging; increased drag on low Earth-orbit satellites and orientation problems may occur.
Navigation - Intermittent satellite navigation (GPS) problems, including loss-of-lock and increased range error may occur.
Radio - HF (high frequency) radio may be intermittent.
Aurora - Aurora may be seen as low as Pennsylvania to Iowa to Oregon.

Space Weather Message Code: WARK04
Serial Number: 5176
Issue Time: 2025 Dec 07 0423 UTC

WARNING: Geomagnetic K-index of 4 expected
Valid From: 2025 Dec 07 0422 UTC
Valid To: 2025 Dec 07 2359 UTC
Warning Condition: Onset

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

Space Weather Message Code: ALTTP4
Serial Number: 698
Issue Time: 2025 Dec 06 2107 UTC

ALERT: Type IV Radio Emission
Begin Time: 2025 Dec 06 2057 UTC



Description: Type IV emissions occur in association with major eruptions on the sun and are typically associated with strong coronal mass ejections and solar radiation storms.

Space Weather Message Code: SUMXM5
Serial Number: 301
Issue Time: 2025 Dec 06 2057 UTC

SUMMARY: X-ray Event exceeded M5
Begin Time: 2025 Dec 06 2029 UTC
Maximum Time: 2025 Dec 06 2039 UTC
End Time: 2025 Dec 06 2049 UTC
X-ray Class: M8.1
Optical Class: 2b
Location: N20E01
NOAA Scale: R2 - Moderate

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact centered primarily on sub-solar point on the sunlit side of Earth.
Radio - Limited blackout of HF (high frequency) radio communication for tens of minutes.

Space Weather Message Code: SUM10R
Serial Number: 892
Issue Time: 2025 Dec 06 2054 UTC

SUMMARY: 10cm Radio Burst
Begin Time: 2025 Dec 06 2035 UTC
Maximum Time: 2025 Dec 06 2036 UTC
End Time: 2025 Dec 06 2039 UTC
Duration: 4 minutes
Peak Flux: 1100 sfu
Latest Penticton Noon Flux: 200 sfu



Description: A 10cm radio burst indicates that the electromagnetic burst associated with a solar flare at the 10cm wavelength was double or greater than the initial 10cm radio background. This can be indicative of significant radio noise in association with a solar flare. This noise is generally short-lived but can cause interference for sensitive receivers including radar, GPS, and satellite communications.

Space Weather Message Code: ALTTP2
Serial Number: 1451
Issue Time: 2025 Dec 06 2051 UTC

ALERT: Type II Radio Emission
Begin Time: 2025 Dec 06 2040 UTC
Estimated Velocity: 1143 km/s



Description: Type II emissions occur in association with eruptions on the sun and typically indicate a coronal mass ejection is associated with a flare event.

Space Weather Message Code: ALTXMF
Serial Number: 504
Issue Time: 2025 Dec 06 2041 UTC

ALERT: X-Ray Flux exceeded M5
Threshold Reached: 2025 Dec 06 2037 UTC
NOAA Scale: R2 - Moderate

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact centered on sub-solar point on the sunlit side of Earth. Extent of blackout of HF (high frequency) radio communication dependent upon current X-ray Flux intensity. For real-time information on affected area and expected duration please see http://www.swpc.noaa.gov/products/d-region-absorption-predictions-d-rap.

Space Weather Message Code: ALTEF3
Serial Number: 3572
Issue Time: 2025 Dec 06 1234 UTC

CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1000pfu
Continuation of Serial Number: 3571
Begin Time: 2025 Dec 05 1530 UTC
Yesterday Maximum 2MeV Flux: 1426 pfu



Potential Impacts: Satellite systems may experience significant charging resulting in increased risk to satellite systems.

Space Weather Message Code: WARK04
Serial Number: 5175
Issue Time: 2025 Dec 06 0852 UTC

EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5174
Valid From: 2025 Dec 06 0205 UTC
Now Valid Until: 2025 Dec 06 2359 UTC
Warning Condition: Persistence

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

Space Weather Message Code: WARK05
Serial Number: 2148
Issue Time: 2025 Dec 06 0837 UTC

WARNING: Geomagnetic K-index of 5 expected
Valid From: 2025 Dec 06 0836 UTC
Valid To: 2025 Dec 06 2359 UTC
Warning Condition: Onset
NOAA Scale: G1 - Minor

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

Space Weather Message Code: ALTK04
Serial Number: 2613
Issue Time: 2025 Dec 06 0258 UTC

ALERT: Geomagnetic K-index of 4
 Threshold Reached: 2025 Dec 06 0256 UTC
Synoptic Period: 0000-0300 UTC
 
Active Warning: Yes

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.