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Northern lights Mayo tonight

Mayo sits at ~54°N magnetic latitude on Ireland's northwest coast - one step below Donegal in the aurora hierarchy but considerably better positioned than the south and east. Kp 4-5 from Achill Island and the Mullet Peninsula. The Wild Atlantic Way coastline faces open ocean with minimal light pollution across a broad area. Ballycroy National Park covers 11,000 hectares without a settlement. Best season: September to March.

Aurora visibility - Mayo

Unlikely tonight

Kp 1 is well below the Kp 4–5 threshold needed for aurora to be visible from Mayo.

Current Kp

of 9

Threshold for Mayo: Kp 4–5 Magnetic latitude: ~54°N Updated: 15 May, 19:41 UTC

↓ Bz — nT Solar wind — km/s Density — p/cm³ ☁ —%

Conditions right now: — Kp + Bz + solar wind + cloud + moon

7-day outlook for Mayo

Today

15 May

Quiet

Tomorrow

16 May

Quiet

Sun

17 May

Quiet

Mon

18 May

Quiet

Tue

19 May

Quiet

Wed

20 May

Quiet

Thu

21 May

Quiet

Based on CME arrival predictions from NASA DONKI. Arrival times ±6 hours.

What Kp is needed here?

Mayo sits at a magnetic latitude of approximately 54°N. The Kp index - a global measure of geomagnetic activity on a scale from 0 (quiet) to 9 (extreme storm), updated every 3 hours - needs to reach Kp 4–5 before the auroral oval expands far enough south to be visible from here.

At Kp 4–5, visibility is possible from Mayo but skies need to be clear and dark. Cloud cover and light pollution remain the main obstacles even when Kp is high enough.

Best dark sky sites near Mayo

Light pollution is the biggest obstacle after cloud cover. These sites give you the best dark northern horizon within reach.

Keem Bay, Achill Island

Keem Bay sits at the far western end of Achill Island, reachable only by a single-track road that climbs over Minaun Heights before descending to the bay. The road ends at a small beach car park. The bay faces west and north across open Atlantic water with no artificial light visible in any direction except the faint glow of Achill village far behind. It is one of the most genuinely dark accessible sites in Ireland.

Mullet Peninsula

The Mullet Peninsula extends north from Belmullet into the North Atlantic, with open water on three sides. From the tip at Erris Head the horizon spans roughly 270 degrees of open ocean. Population on the peninsula is sparse and there are no towns to the north or west to produce competing light. The flat terrain gives unobstructed sky views from close to sea level. It is among the least light-polluted peninsulas in Ireland.

Ballycroy National Park

Ballycroy is Ireland's largest uninhabited area, covering 11,000 hectares of Atlantic blanket bog on the Mayo coast between Achill and Bangor Erris. There are no settlements within the park. The open bogland gives wide sky views with an uninterrupted northern horizon. The park is accessible from the N59 near Ballycroy village. Light pollution readings here are comparable to Scotland's darkest upland areas.

Best time to see the northern lights in Mayo

Mayo's aurora season runs from late September through to March, when nights are long enough for truly dark skies. The equinox months, September and March, bring a natural boost in geomagnetic activity, making them statistically the best of the season. Summer months bring too much twilight for aurora to be visible at this latitude.

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

Activity peaks around the September and March equinoxes, when Earth's magnetic field geometry is most favourable for coupling with the solar wind. Events during these two windows tend to produce the strongest displays of the year for observers at Mayo's latitude.

April through August brings persistent astronomical twilight that washes out aurora completely. Even strong events (Kp 6+) remain invisible during this period because the sky never gets dark enough.

Other Ireland aurora forecasts

← Ireland overview

Donegal

Unlikely

Northernmost county, Malin Head dark sky

~55°N mag. lat. Kp 5

Galway

Unlikely

West coast, Connemara dark sky

~53°N mag. lat. Kp 6-7

Kerry

Unlikely

Iveragh Peninsula, Valentia Island, Atlantic coast

~52°N mag. lat. Kp 5

Northern Lights Ireland

Ireland aurora hub - all counties with current Kp status.

Northern Lights Donegal Tonight

Donegal - Ireland's top aurora county at 55°N magnetic latitude.

Northern Lights Kerry Tonight

Kerry - Valentia Island and the Iveragh Peninsula.

Northern Lights Galway Tonight

Galway - Connemara and the west coast.

What Is the Kp Index?

What Kp 4-5 means at 54°N magnetic latitude.

Common questions

Aurora watching in Mayo - Achill Island, the Mullet Peninsula, and the Wild Atlantic Way.

Can you see the northern lights in Mayo?

Yes. Mayo is one of Ireland's most aurora-favourable counties. At approximately 54°N magnetic latitude, it sits one step below Donegal in the aurora hierarchy but well above the south and east of Ireland. Kp 4-5 is needed from Achill Island and the Mullet Peninsula. The Kp index is a global measure of geomagnetic activity on a scale from 0 (quiet) to 9 (extreme storm), updated every 3 hours. During G2 storms, aurora is regularly observed from Mayo's north-west coast.

How does Mayo compare to Donegal for aurora?

Donegal at 55°N magnetic latitude has a slight edge - the auroral oval reaches it slightly more often, and the aurora sits higher in the sky during active periods. Mayo at 54°N is the next best option, with similar sky darkness and an equally wide Atlantic horizon. The difference in practice is small: the same G2 storm that produces aurora from Malin Head in Donegal will also produce it from Keem Bay in Mayo. Both counties share a similar ocean-facing, low-population-density coastline.

What Kp is needed to see aurora in Mayo?

Kp 4-5 from the darkest coastal sites. The Kp index is a global measure of geomagnetic activity on a scale from 0 (quiet) to 9 (extreme storm), updated every 3 hours. At 54°N magnetic latitude, Kp 4 can occasionally be enough during sub-storm enhancements that briefly push the auroral oval south, but sustained Kp 5 is a more reliable threshold. From Keem Bay and the Mullet Peninsula, the low light pollution means even a faint display is detectable with a camera. From Ballina or Castlebar, Kp 6 would be needed.

Is Achill Island a good place to see aurora?

Yes. Keem Bay at the far end of Achill Island is one of Ireland's strongest aurora sites. The bay faces west and north with no light pollution in those directions, and road access ends at the beach car park - you cannot drive further, which keeps visitor numbers low. The single-track road over Minaun Heights can be treacherous in ice, so winter visits require care. The bay itself gives a genuine dark sky experience. Achill Sound and Achill village are much brighter and not suitable as aurora sites.

How dark are Mayo's skies compared to other Irish counties?

Mayo has some of Ireland's lowest light pollution. Ballycroy National Park records sky darkness on a par with Scotland's darkest upland areas - well below the threshold for seeing the Milky Way with the naked eye. The Mullet Peninsula and outer Achill are in a similar category. The main sources of artificial light in the county are Westport, Castlebar, and Ballina, all of which are far enough from the coastal aurora sites to have little impact. Only parts of Donegal and west Kerry match Mayo's overall sky quality.