Solar Activity Report for 1/21/04
- ** G-1 Geomagnetic Storm In Progress **
** Aurora Watch In Effect **
A full-halo CME from a C-class flare on the 19th struck home this
evening, triggering a G-1 geomagnetic storm, which is sstill in
progress. While the interplanetary magnetic field held onto a
north-pointing orientation, aurora are still a possibility tonight,
especially in the higher latitudes. A C-class flare is not strong as
flares go, not even making the significant flare category. What made
this flare capable of firing off a CME was its duration. This flare
was a long duration event, which has a higher likelyhood of producing
a CME. In contrast, an M-6 class flare which immediately followed the
C-6 flare, while much stronger, was a short duration event, and didn't
produce a CME. The active conditions are expected to last for at
least another 24 hours before dying down. After that, we could see
some effects from a small coronal hole around the first of next week.
Sunspot region 540, the source of both of the aforementioned flares,
is capable of producing more M-class events.
The current solar and geomagnetic conditions are :
NOAA sunspot number : 104
SFI : 130
A index : 11
K index : 5
Solar wind speed : 649.4 km/sec
Solar wind density : 14.1 protons/cc
Solar wind pressure : 10.3 nPa
IMF : 15.9 nT
IMF Orientation : 6.3 nT North
Conditions for the last 24 hours :
Space weather for the past 24 hours has been minor. Geomagnetic storms
reaching the G1 level occurred.
Forecast for the next 24 hours :
Space weather for the next 24 hours is expected to be minor.
Geomagnetic storms reaching the G1 level are expected. Radio blackouts
reaching the R1 level are expected.
Solar activity forecast :
Solar activity is expected to be at low to moderate levels.
Geomagnetic activity forecast :
The geomagnetic field is expected to range from quiet to minor storm
levels. Isolated periods of major storm conditions are possible with
the onset of the anticipated shock passage, due early on 22 Jan;
resulting from the long duration C-flare that occurred late on 19 Jan.
Unsettled to active levels are expected on 23 Jan. Predominantly quiet
to unsettled conditions should return by 24 Jan.
Recent significant solar flare activity :
20-Jan-2004 0743Z M6.1
19-Jan-2004 1240Z M1.0
19-Jan-2004 0532Z M1.0