A series of strong solar flares in the past fews days has prompted the NOAA Space Weather Prediction Center to issue a G4 severe-geomagnetic-storm watch for Earth for the first time in nearly 20 years. The storm is expected to reach the planet on Friday and might continue through the weekend. It could give much of the U.S. a rare opportunity to view the northern lights (aurora borealis) in the nighttime sky as far south as Alabama and also potentially disrupt communications and power grids. It’s the second rare sun-related event in the U.S. this year, following the awesome total solar eclipse in March. Below is a quick look at what to expect from the big storm.
When will the geomagnetic storm hit?
On Thursday, the Space Weather Prediction Center announced a geomagnetic storm watch with a severity rating of 4 out of 5 — the first G4-rated storm since 2005 — with the storm beginning to arrive around 8 p.m. ET Friday and lasting through Sunday. The peak is expected early Saturday between 2 a.m. and 5 a.m. ET — but the precise timing is hard to predict.
Large sunspot groups and strong solar flares led to the issuance of SWPC's first G4 Watch since 2005... pic.twitter.com/oi55cTPXhP
— NOAA Space Weather Prediction Center (@NWSSWPC) May 9, 2024
What is the cause of this unusual space weather event?
The NOAA says a large cluster of sunspots has produced multiple solar flares and at least five large coronal mass ejections (CME) since Wednesday, which have shot clouds of plasma and charged particles toward Earth. These CMEs are expected to merge before they hit the planet, which is why the severity rating is so high.
Where, when, and how can I see the northern lights produced by the storm?
The aurora borealis will be visible a lot of places far south of where you usually need to be to see them, provided there are clear skies and not too much light pollution (like from a nearby metropolis). Depending on where you are, you will also need to know where in the sky to look. Explains the Washington Post:
Current forecasts project the lights could be seen as far south as Alabama to northern California, according to the National Oceanic and Atmospheric Administration’s Space Weather Prediction Center. Chances of seeing the lights will be highest in the northern United States, Canada and northern Europe.
To maximize your chances of seeing auroras Friday night, find a dark sky location away from city lights. You’ll also want cloud-free skies. Unfortunately, considerable cloud cover will be spread over the Great Lakes, Mid-Atlantic and Northeast, although some gaps in the cloud canopy are probable. Clear skies are most likely over the central states and West Coast.
Whoa. If it’s clear where you are, just look up. If you’re south of the #Auroraborealis ring, look north. This is potentially going to be a spectacular event, but it won’t be Carrington levels. Whew. pic.twitter.com/UjQBLG0buf
— Mark Robinson (@StormhunterTWN) May 10, 2024
Maximum potential for northern lights visibility tonight:
— Peter Forister ???????????? (@forecaster25) May 10, 2024
Naked-eye visible down to the the Carolinas and Oklahoma
Possible to view on the horizon to Florida and Southern California.
G4 storm forecast is the highest in 19 years. pic.twitter.com/0ToukB4D0u
It’s also possible that auroras not visible to the naked eye will be visible if you use your smartphone camera.
Will the storm disrupt power or cause communication blackouts?
Severe geomagnetic storms can cause problems with power grids and disrupt communications networks, and damage satellites (and spacecraft), but the NOAA doesn’t seem too concerned about widespread problems this time around, though it is working with power grid operators to monitor the impact.
