Solar Activity Report for 8/17/03
- View Source** G-1 Geomagnetic Storm In Progress **
** Aurora Watch In Effect **
Criminy! I miss a couple of days, and all heck breaks loose! What's
really interesting is that it was completely unexpected. Both the
SOHO and ACE satellites registered a shock wave passage around 1400Z
Sunday. That surprised some folks, as nobody had thought there was
anything on the way. A weak full-halo CME was observed on the 14th,
but it was thought that it was a back side event, and headed directly
away from us. Surprise!! Just goes to show you that solar and
geomagnetic forecasting sometimes can be a bit difficult. At any
rate, when the shock wave hit Earth's magnetosphere, the
Interplanetary Magnetic Field swung sharply north, which tends to
suppress geomagnetic activity. However, now it has swung equally
sharply south, and a geomagnetic storm is in progress. I would not be
at all surprised if aurora are being seen across Canada and the
northers US tonight. Whatever it was that kicked off the CME on the
14th had to have been a pretty weak event to not have even been really
noticed. As I've said before, however, you don't necessarily need a
strong flare to fire off a nice CME. Expect the current activity
conditions to last into Monday before settling down. Then, be on the
lookout for another coronal hole by the middle of the week.
The current solar and geomagnetic conditions are :
NOAA sunspot number : 113
SFI : 119
A index : 14
K index : 5
Solar wind speed : 503.0 km/sec
Solar wind density : 4.0 protons/cc
Solar wind pressure : 1.7 nPa
IMF : 19.9 nT
IMF Orientation : 13.0 nT South
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.
Solar activity forecast :
Solar activity is expected to be at low levels with the chance of an
isolated M-class event from Region 431.
Geomagnetic activity forecast :
The geomagnetic field is expected to be at quiet to active levels on
day one due to residual effects from the shock. Quiet to unsettled
levels are expected on day two and day three.
Recent significant solar flare activity :