Tuesday, April 24, 2012

Todays Solar Flare Activity April 24 2012 Causing Geomagnetic Storm Aurora

C-Class Flare and CME
A couple of new sunspots are rotating into view off the eastern limb. One of these regions located off the northeast limb produced a C3.7 Solar Flare at 07:45 UTC this morning and was associated with a Type II Sweep Frequency Event and CME. Due to the spots location, the plasma cloud should be directed mostly towards the east.

ALERT: Type II Radio Emission
Begin Time: 2012 Apr 24 0748 UTC
Estimated Velocity: 1029 km/s
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.

IA. Analysis of Solar Active Regions and Activity from 22/2100Z
to 23/2100Z: Solar activity has been at low levels for the past 24
hours. There are currently 8 active regions on the disk, with 5
regions having sunspots. The spotted regions on the disk all
remained rather quiet and stable throughout the period. However,
around plage Region 1461 (N10W19), two C-class events were observed
today with associated Earth directed CMEs.

IB. Solar Activity Forecast: Solar activity is expected to be at
low levels with a chance for M-class x-ray events for the next three
days (24 - 26 April).

IIA. Geophysical Activity Summary 22/2100Z to 23/2100Z:
The geomagnetic field has been at quiet to minor storm levels for the
past 24 hours. Observations made by the ACE spacecraft, around
23/0200Z, indicated the arrival of a CME that lifted off the solar
disk on 19 April. Solar wind velocities increased from 350 - 400
km/s with the total IMF reaching around 18 nT. The Boulder
magnetometer measured a 31 nT sudden impulse at 23/0325Z in
conjunction with the CME arrival here at Earth. From then on, active
to minor storm levels were observed due to multiple periods of
sustained negative Bz.

IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be at quiet to active levels with a slight chance for a
minor storm on day 1 (24 April) as effects from the CME wane and a
coronal hole high speed stream (CH HSS) moves in. Quiet to active
levels are expected on day two (25 April) as the effects of the CH
HSS continue. An increase to quiet to minor storm levels are
expected on day three (26 April) as the two CMEs, observed earlier
in the period, are expected to become geoeffective.