Recent storms on the sun have sent a flood of charged particles toward Earth.

This raises the potential for what space weather forecasters refer to as a GEOMAGNETIC STORM. Such storms result from an interaction between a flood of charged particles propelled toward Earth by Coronal Mass Ejections (CMEs)—giant storms on the sun which are often seen as immense flares, the scale of which is evident from the accompanying NASA graphic, and the magnetic field which surrounds our planet.

These storms can impact radio communications, earth-orbiting satellites, power grids and pipelines, especially at high latitudes, and set in play auroral displays we refer to as Northern Lights.

HERE’S WHY NORTHERN LIGHTS FORECASTS CAN BE DICEY—

The flood of charged particles, referred to as plasma, MUST be Earth directed, reach the upper atmosphere at times where sunlight doesn’t interfere with viewing the resulting northern lights displays plus it must actually make contact with Earth’s magnetic layer.

If the flood of particles misses Earth and just passes by or if they hit during periods outside the darkness of night, then observers may be denied an auroral display.

History has shown forecasts of Northern Lights are tricky and may not always end up producing a northern lights display which is observable. These plasma discharges are modeled, but as vast as they are don’t always hit the mark– namely Earth’s atmosphere–which compared to the vastness of space, is a comparatively small target.

————————————————————————–

HERE ARE THE PERIODS WITH THE GREATEST POTENTIAL FOR AURORAL DISPLAYS AND OTHER GEOMAGNETIC STORM IMPACTS:

G3 Watch

Thursday, Aug. 18, the surges of plasma from multiple Coronal Mass Ejections (CMEs) are expected to arrive near the Earth, leading to an escalated geomagnetic response. Communications on Earth may be disrupted, including power grids, GPS and other satellite means.

NOAA’s Space Weather Prediction Center says this could set off a display of Northern Lights farther south than they normally occur, potentially making the auroras borealis visible in parts of the Midwest, the far northeast, and parts of the north-central states.

Areas as far south as Pennsylvania, Illinois and Iowa may see the aurora.

G2 Watch

CME influences are expected to continue on Aug. 19, prompting a moderate geomagnetic storm watch for the end of the week.

NOTE: I’m including forecasts of potential auroral activity from the University of Alaska-Fairbanks.

FROM NOAA’S SPACE WEATHER CENTER–More information

Here’s a list of potential impacts:

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.

————————————————————————–

Here is a technical discussion of the GEOMAGNETIC STORM WATCH from forecasters at NOAA’s Space Weather Center:

G1-G3 Watches for 17-19 August 2022published: Tuesday, August 16, 2022, 22:46 UTC

Geomagnetic storm watches are in effect for 17-19 August 2022 due to likely CH HSS and CME influences. A recurrent coronal hole (CH) high speed stream (HSS) is anticipated to connect with Earth first, on 17 Aug. The resultant elevated and disturbed solar wind field is thought to be enough for potential G1 (Minor) geomagnetic storm conditions on 17 Aug. Geomagnetic responses are likely to escalate to G3 (Strong) conditions on 18 Aug due to the arrival at or near Earth of multiple coronal mass ejections (CMEs) that have departed the Sun since 14 Aug. Despite the numerous CMEs, most are expected to have little to no impact at Earth, however, at least four have potential Earth-directed components. The most recent flare-associated CME took place from small, but complex, Region 3078 at 3:58 am EDT (0758 UTC) on 16 Aug, while the first CME in this chain of activity took place on 14 Aug. Forecast confidence is low to moderate regarding Earth impact of these CMEs, as most of the ejecta is expected to pass either ahead or south of Earth’s orbit. However, model runs indicate combined arrival of some of these CMEs at or in the vicinity of Earth beginning 18 Aug – therefore, the G3 (Strong) storm watch is in effect for that day. Any CME influences are likely to continue on 19 Aug and a G2 (Moderate) storm watch is posted accordingly.When the CME approaches Earth, NOAA’s DSCOVR satellite will be among the first spacecraft to detect the real-time solar wind changes and SWPC forecasters will issue any appropriate warnings. Impacts to our technology from a G3 storm are usually minimal. However, a G3 storm has the potential to drive the aurora further away from its normal polar residence, and if other factors come together, the aurora might be seen over portions of Pennsylvania, Iowa, to northern Oregon. For additional information about space weather, geomagnetic storms, aurora and viewing tips, and CMEs – click the terms. NOAA’s Space Weather Prediction Center is the official source for space weather forecasts, watches, warnings and alerts. Visit www.spaceweather.gov for updates.