Moderately strong M1.4 solar flare and CME produced by Region 2403

A second M-class solar flare of the day erupted from Region 2403 at 09:48 UTC on August 21, 2015. The event started at 09:34, peaked at 09:48 as M1.4 solar flare, and ended at 10:07 UTC. Radio signatures suggest a Coronal Mass Ejection (CME) was produced. These are the first M-class solar flares since July 6, 2015.

As we reported earlier, Region 2403 has Beta-Gamma magnetic configuration, it is rotating into a more geoeffective position, and is capable of producing strong eruptions on Sun. CMEs produced by this region in the days ahead could be directed toward Earth.

A Type II Radio Emission with estimated velocity of 490 km/s was registered starting at 09:59 UTC. Additionally, a Type IV Radio Emission was also associated with the event. Type IV emissions occur in association with major eruption on the Sun and are typically associated with strong CMEs and solar radiation storms.

Coronagraph imagery is still not available.

SWPC alerts

Space Weather Message Code: ALTTP2
Serial Number: 1020
Issue Time: 2015 Aug 21 1032 UTC

ALERT: Type II Radio Emission
Begin Time: 2015 Aug 21 0959 UTC
Estimated Velocity: 490 km/s

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Description: Type II emissions occur in association with eruptions on the sun and typically indicate a coronal mass ejection is associated with a flare event.

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Space Weather Message Code: ALTTP4
Serial Number: 510
Issue Time: 2015 Aug 21 1039 UTC

ALERT: Type IV Radio Emission
Begin Time: 2015 Aug 21 0942 UTC

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Description: Type IV emissions occur in association with major eruptions on the sun and are typically associated with strong coronal mass ejections and solar radiation storms.

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Sunspots

There are currently 3 numbered sunspot regions on the Earth side of the Sun.

Region 2403 exhibited slight growth in its leader and intermediate spots yesterday, with the majority of the growth in the leader spot area.

Region 2401 was mostly inactive, and exhibited slight decay in its trailer spots area.

Image credit: ESA / PROBA2/SWAP

2401 – Beta
2403 – Beta-Gamma
2404 – Beta

Forecast

Solar activity is expected to be low, with a slight chance for M-Class (R1-R2, Minor-Moderate) activity over the next 3 days (August 21 to 23), SWPC said in their Forecast Discussion issued 00:30 UTC on August 21.

The greater than 2 MeV electron flux is expected to be at moderate to high levels, with a chance for very high levels, over the next three days. The greater than 10 MeV proton flux is expected to remain at background levels (Below S1-Minor). 

The solar wind environment is expected to remain slightly disturbed on August 21 and 22 as the positive polarity CH in the north remains in a potentially geoeffective position.

Early on August 23, a recurrent, equatorial, positive polarity CH is expected to further influence the solar wind environment, enhancing the wind speed, mag field, temperature, and density. G1 – Minor geomagnetic storm levels are expected as a result.

This page will be updated.

Image credit: NASA SDO/AIA 304 at 09:48 UTC on August 21, 2015.