Solar Storm Watch WARNING: Geomagnetic G3 Storm K-index 7 or Greater Expected 2-27-23

Solar Storm Watch WARNING Geomagnetic G3 Storm K index of 7 or greater expected 2 27 23 1

NOAA Space Weather

NOAA started this morning with a Solar Storm Watch Warning for a Geomagnetic G3 Storm K-index of 7 or greater expected at 5:54 Coordinated Universal Time (UTC) on Monday 2-27-23.

Geomagnetic Solar Storm affect on the planet and near earth space could be extremely strong. Affected areas and components could be spacecraft, power grids, navigation systems, and radio systems.

Space Weather Message Code: WARK07
Serial Number: 85
Issue Time: 2023 Feb 27 1354 UTC

WARNING: Geomagnetic K-index of 7 or greater expected
Valid From: 2023 Feb 27 1353 UTC
Valid To: 2023 Feb 27 1800 UTC
Warning Condition: Onset
NOAA Scale: G3 or greater - Strong to Extreme

NOAA Space Weather Scale descriptions can be found at

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.

NOAA Space Weather Solar Geomagnetic Storm Scale

ScaleDescriptionEffect / Reaction
G5*ExtremePower systems: Some power grid systems may experience complete collapse or blackouts. Transformers may experience damage.
Spacecraft operations: May experience extensive surface charging, problems with orientation, uplink/downlink, and tracking satellites.
Other systems: HF (high frequency) radio transmission may be impossible in many areas for days or more.
G4SeverePower systems: Possible widespread voltage control problems and some protective systems will mistakenly trip out key assets from the grid.
Spacecraft operations: Possible surface charging, tracking, and orientation problems.
Other systems: HF radio propagation sporadic, satellite navigation degraded for hours, low-frequency radio navigation disrupted.
G3StrongPower systems: Voltage corrections may be required, and false alarms triggered on some protection devices.
Spacecraft operations: Surface charging and drag may increase on low-Earth-orbit satellites, and corrections may be needed for orientation problems.
Other systems: Intermittent satellite navigation and low-frequency radio navigation problems may occur, and HF radio may be intermittent.
G2ModeratePower systems: High-latitude power systems may experience voltage alarms, and long-duration storms may cause transformer damage.
Spacecraft operations: Corrective actions required and possible changes in drag affect orbit predictions.
Other systems: HF radio propagation can fade at higher latitudes.
G1MinorPower systems: Weak power grid fluctuations can occur.
Spacecraft operations: Minor impact on satellite operations possible.
Other systems: Migratory animals are affected at G1 and higher levels.
Table 1: NOAA Space Weather Solar Geomagnetic Storm Scale

*This scale does not include unknown variables of a Solar Storms stronger than a G5 level.

Additional Geomagnetic Storm Information

For additional information please see our articles “What To Do Before a G5 or Greater Geomagnetic Storm?” and “Should You Be Worried About Weather-Caused Power Grid Outages?”

Fremontii, LLC. is compensated for referring traffic and business and as an Amazon Associate, we earn from qualifying purchases. By using the affiliate links, you are helping support our Website, and we genuinely appreciate your support.

John Mortensen

As a kid I wanted to be an astronaut, geologist, or scientist. I became a project manager which is involved with many of those things. I am a project manager and tech writer who researches the latest alternative and green technologies. We write helpful articles about green electronics and green technology products. AI, extreme weather, electric vehicles, are all in our future and we want to know the best way to deal with the effects of these on the power grid and emergency preparedness.

Recent Posts