A forecasted auroral display for North American time zones tonight, Thursday, or early Friday morning is subject to significant uncertainty due to the anticipated arrival of a coronal mass ejection (CME). The forecast, relayed by space physics PhD student and aurora forecaster Vincent Ledvina, originates from NOAA's Space Weather Prediction Center (SWPC), the nation's official source for space weather alerts and forecasts. While optimism exists, several critical factors could diminish or entirely prevent visibility.
The CME's arrival is primarily anticipated around 08-08 at 6-9 UTC, though a considerable "roughly +/- 7 hr uncertainty" surrounds this timing, as stated by Ledvina. Compounding this, most agencies are forecasting only a "glancing blow" from the eruption, meaning the CME "could miss us entirely" or interact minimally with Earth's magnetic field. Ledvina advises enthusiasts to "be prepared for a total dud, but still have cautious optimism the CME will eventually arrive."
Visibility challenges further complicate the outlook for potential aurora watchers. Widespread smoke from Canadian wildfires continues to cover many areas in the Lower 48, creating hazy skies that scatter light and dim faint auroral glows. Additionally, a full moon is currently present, acting as natural light pollution that can wash out subtle displays, making it "difficult" to see the aurora with the naked eye. For optimal viewing, clear, dark, and moonless skies are generally preferred.
For any aurora to be visible, three key conditions must align. First, the CME needs to actually impact Earth, rather than delivering a glancing blow or missing entirely, allowing its magnetic fields to interact with Earth's. Second, the CME must be strong enough to produce auroral displays visible from mid-latitudes, often requiring "quick bursts of activity called substorms." These substorms are sudden releases of energy in Earth's magnetosphere, accelerating charged particles that cause bright, dynamic auroral displays. Third, the CME's effects must endure long enough to coincide with nighttime at the observer's location, as some CMEs dissipate within half a day.
Vincent Ledvina, a PhD student specializing in auroral research and a prominent aurora photographer, is known for his ability to communicate complex space weather phenomena. He advises potential viewers to monitor his social media for real-time updates on the CME's impact. He also recommends learning how to forecast substorms using GOES magnetometers, which measure Earth's magnetic field and can indicate geomagnetic activity. Enthusiasts can also monitor webcams for aurora activity near their location to gauge real-time visibility.