NOAA Space Weather NOAA has issued a Space Weather Storm Watch over the next three days and a Category G2 Geomagnetic Storm is Predicted for Saturday February 18, 2023. The following is the report from NOAA issued this morning. Highest Geomagnetic Storm Level Predicted by Day: Feb 16: G1 (Minor) Feb 17: G1 (Minor) Feb 18: G2 (Moderate) THIS SUPERSEDES ANY/ALL PRIOR WATCHES IN EFFECT 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. If you have further questions, 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?"
NOAA Space Weather Solar Geomagnetic Storm Scale
| Scale | Description | Effect / Reaction |
| G5* | Extreme | Power 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. |
| G4 | Severe | Power 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. |
| G3 | Strong | Power 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. |
| G2 | Moderate | Power 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. |
| G1 | Minor | Power 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. |
*This scale does not include unknown variables of a Solar Geomagnetic Storm stronger than a G5.