Glancing blow to Earth’s magnetic field expected late on March 25

Active region 2014 (S14E20, Dsc/beta-gamma) produced a long duration C5 solar flare on March 23, 2014 at 03:48 UTC. This flare lasted several hours and thus produced energy equivalent to much stronger flares.

A Coronal Mass Ejection (CME) associated with this event was observed in SOHO LASCO C2 imagery beginning at 05:00 UTC. Although WSA-ENLIL model output shows arrival midday on March 26, due to observed solar wind speed values being higher than indicated on the model output, CME arrival is expected late on March 25 or early on March 26.

SOHO LASCO C3 image showing CME from long duration C5 solar flare on March 23, 2014.

Sunspots

There are currently 9 numbered sunspot regions on the Earth side of the Sun. Regions 2010 (S15W13, Dac/beta-gamma-delta), 2014 (S14E20, Dsc/beta-gamma), and 2017 (N09E45, Dai/beta-gamma) all exhibited moderate growth yesterday. Region 2015 (S14W42, Cao/beta-delta) is being the most magnetically complex regions on the visible disk.

Sunspots on March 24, 2014. Image credit: NASA SDO / HMI

2005 N12W74 263 160 3 HSX 1 A
2008 S07W47 236 30 7 CRO 6 B
2010 S15W13 202 180 9 DAC 26 BGD
2011 S06W92 280 110 9 CAO 4 B
2013 N14E03 186 20 2 CAO 2 B
2014 S14E20 169 190 8 DSC 16 BG
2015 S14W42 231 90 4 CAO 4 BD
2016 S28W07 196 10 1 AXX 1 A
2017 N09E45 144 100 5 DAI 9 BG

Forecast

Solar wind parameters were indicative of continued weak influence of a positive polarity coronal hole high speed stream (CH HSS) yesterday. Solar wind speeds are expected to remain enhanced (450-550 km/s) for the next three days (March 24 – 26) due to a combination of CH HSS influence early in the period and CME effects mid to late in the period.

NOAA SWPC forecasters estimate 45% chance for M-class solar flare, and 5% chance for X-class solar flares in next 3 days.

Featured image: NASA/ESA SOHO LASCO C3