Status Report

Joint USAF/NOAA Report of Solar and Geophysical Activity 09 Jan 2004

By SpaceRef Editor

January 9, 2004

Filed under Space Weather Prediction Center (NOAA), Space Weather Solar-Geophysical Activity, US

Prepared jointly by the U.S. Dept. of Commerce, NOAA, Space Environment Center and the U.S. Air Force.

Updated 2004 Jan 09 2210 UTC

Joint USAF/NOAA Report of Solar and Geophysical Activity 09 Jan 2004

SDF Number 009 Issued at 2200Z on 09 Jan 2004

IA. Analysis of Solar Active Regions and Activity from 08/2100Z
to 09/2100Z: Solar activity was moderate during the last 24 hours.
Region 537 (N05E37) produced back-to-back M-class flares, an M1 at
0122 UTC followed immediately by an M3 at 0144 UTC. The x-ray events
were associated with a narrow CME erupting off the southeast solar
limb. Region 537 continues to have a delta configuration and is
growing slowly, The spots appeared to be rotating slightly in a
counter-clockwise direction. Region 536 (S12W28) is still the
largest group on the disk and is undergoing a net loss of total spot
area. However, there is some opposite polarity flux emerging just to
the east of the region, and the spot group did produce occasional
small flares throughout the day.

IB. Solar Activity Forecast: Solar activity is expected to be
predominantly moderate. There continues to be a slight chance for
major flare activity from Region 536 and from Region 537.

IIA. Geophysical Activity Summary 08/2100Z to 09/2100Z:
The geomagnetic field was at unsettled to minor storm levels during
the past 24 hours. An initially unsettled geomagnetic field became
more disturbed after 0600 UTC, with one minor storm period from
0600-0900 UTC, followed by unsettled to active conditions for the
rest of the day. The increase was likely due to an observed change
in the character of the solar wind around 0500 UTC. ACE solar wind
data showed a slow rise in velocity, temperature, and density, as
well as an increase in the total magnetic field intensity for about
4.5 hours accompanied by moderately southward Bz. The spiral angle
also went through a reversal from away to towards just after 0600 Z
and back from towards to away around 1000Z. This may be indicative
of passage through an interplanetary current sheet. After 1000Z,
velocity and speed continued to rise along with temperature,
possibly suggestive of the onset of a co-rotating interaction
region. The greater than 2 MeV electron fluxes were at high levels
during the past 24 hours.

IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be unsettled with occasional active periods over the
next three days. The main driver for this enhanced activity is
expected to be the continued presence of high speed solar wind
originating from a solar coronal hole.

III. Event Probabilities 10 Jan-12 Jan