Space Weather Alerts

Space Weather Message Code: ALTK06
Serial Number: 679
Issue Time: 2025 Dec 11 0252 UTC

ALERT: Geomagnetic K-index of 6
 Threshold Reached: 2025 Dec 11 0242 UTC
Synoptic Period: 0000-0300 UTC
 
Active Warning: Yes
NOAA Scale: G2 - Moderate

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

Potential Impacts: Area of impact primarily poleward of 55 degrees Geomagnetic Latitude.
Induced Currents - Power grid fluctuations can occur. High-latitude power systems may experience voltage alarms.
Spacecraft - Satellite orientation irregularities may occur; increased drag on low Earth-orbit satellites is possible.
Radio - HF (high frequency) radio propagation can fade at higher latitudes.
Aurora - Aurora may be seen as low as New York to Wisconsin to Washington state.

Space Weather Message Code: SUM10R
Serial Number: 895
Issue Time: 2025 Dec 11 0016 UTC

SUMMARY: 10cm Radio Burst
Begin Time: 2025 Dec 10 2206 UTC
Maximum Time: 2025 Dec 10 2206 UTC
End Time: 2025 Dec 10 2208 UTC
Duration: 2 minutes
Peak Flux: 520 sfu
Latest Penticton Noon Flux: 168 sfu

Comment: This summary contains the corrected peak flux of 520 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: SUM10R
Serial Number: 894
Issue Time: 2025 Dec 11 0014 UTC

CANCEL SUMMARY: 10cm Radio Burst
Cancel Serial Number: 893
Original Issue Time: 2025 Dec 10 2226 UTC

Comment: the total flux was 520 sfu instead of the reported one. 



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: ALTK06
Serial Number: 678
Issue Time: 2025 Dec 10 2244 UTC

ALERT: Geomagnetic K-index of 6
 Threshold Reached: 2025 Dec 10 2243 UTC
Synoptic Period: 2100-2400 UTC
 
Active Warning: Yes
NOAA Scale: G2 - Moderate

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

Potential Impacts: Area of impact primarily poleward of 55 degrees Geomagnetic Latitude.
Induced Currents - Power grid fluctuations can occur. High-latitude power systems may experience voltage alarms.
Spacecraft - Satellite orientation irregularities may occur; increased drag on low Earth-orbit satellites is possible.
Radio - HF (high frequency) radio propagation can fade at higher latitudes.
Aurora - Aurora may be seen as low as New York to Wisconsin to Washington state.

Space Weather Message Code: ALTTP2
Serial Number: 1455
Issue Time: 2025 Dec 10 2229 UTC

ALERT: Type II Radio Emission
Begin Time: 2025 Dec 10 2208 UTC
Estimated Velocity: 849 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: SUM10R
Serial Number: 893
Issue Time: 2025 Dec 10 2226 UTC

SUMMARY: 10cm Radio Burst
Begin Time: 2025 Dec 10 2206 UTC
Maximum Time: 2025 Dec 10 2206 UTC
End Time: 2025 Dec 10 2208 UTC
Duration: 2 minutes
Peak Flux: 2695 sfu
Latest Penticton Noon Flux: 168 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: ALTK05
Serial Number: 1926
Issue Time: 2025 Dec 10 2213 UTC

ALERT: Geomagnetic K-index of 5
 Threshold Reached: 2025 Dec 10 2207 UTC
Synoptic Period: 2100-2400 UTC
 
Active Warning: Yes
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: WARK05
Serial Number: 2150
Issue Time: 2025 Dec 10 2207 UTC

EXTENDED WARNING: Geomagnetic K-index of 5 expected
Extension to Serial Number: 2149
Valid From: 2025 Dec 10 2115 UTC
Now Valid Until: 2025 Dec 11 0600 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 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: WARK04
Serial Number: 5179
Issue Time: 2025 Dec 10 2206 UTC

EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5178
Valid From: 2025 Dec 10 2040 UTC
Now Valid Until: 2025 Dec 11 0900 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: WARK06
Serial Number: 628
Issue Time: 2025 Dec 10 2157 UTC

WARNING: Geomagnetic K-Index of 6 expected
Valid From: 2025 Dec 10 2200 UTC
Valid To: 2025 Dec 11 0300 UTC
Warning Condition: Onset
NOAA Scale: G2 - Moderate

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

Potential Impacts: Area of impact primarily poleward of 55 degrees Geomagnetic Latitude.
Induced Currents - Power grid fluctuations can occur. High-latitude power systems may experience voltage alarms.
Spacecraft - Satellite orientation irregularities may occur; increased drag on low Earth-orbit satellites is possible.
Radio - HF (high frequency) radio propagation can fade at higher latitudes.
Aurora - Aurora may be seen as low as New York to Wisconsin to Washington state.

Space Weather Message Code: ALTK04
Serial Number: 2615
Issue Time: 2025 Dec 10 2120 UTC

ALERT: Geomagnetic K-index of 4
 Threshold Reached: 2025 Dec 10 2111 UTC
Synoptic Period: 2100-2400 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: WARK05
Serial Number: 2149
Issue Time: 2025 Dec 10 2117 UTC

WARNING: Geomagnetic K-index of 5 expected
Valid From: 2025 Dec 10 2115 UTC
Valid To: 2025 Dec 11 0300 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.