Solar Active Region Produces Intense Solar Flare

NOAA Space Environment Center
Boulder, Colorado

SPACE WEATHER ADVISORY BULLETIN #03-3
2003 October 28 at 10:55 a.m. MST
(2003 October 28 1755 UTC)

SOLAR ACTIVE REGION PRODUCES INTENSE SOLAR FLARE

The dynamic solar regions reported on 21 October continue to produce high levels
of solar activity. NOAA Region 486 produced a category R4 (severe) radio
blackout with an associated category S3 (strong) solar radiation storm on 28
October at 1110 UTC (6:10 A.M. EST). The SOHO/LASCO instruments also observed a
full halo coronal mass ejection with this activity, which is Earth directed
[http://science.nasa.gov/spaceweather...me_c3_big.gif]. This
region is the second largest in size this solar cycle
[http://www.spaceweather.com/solarflares/topflares.html].

As a result of this activity a category G4 (severe) geomagnetic storm is
expected with periods of category G5 (extreme) levels possible. The solar
radiation storm is also expected to continue at strong (G3) levels for the next
48 hours.

Further major eruptions are possible from these active regions as they rotate
across the face of the sun over the next few days. Agencies impacted by solar
flare radio blackouts, geomagnetic storms, and solar radiation storms may
experience disruptions through this period. These include spacecraft operations,
electric power systems, HF communications, and navigation systems.