Status Report

Joint USAF/NOAA Report of Solar and Geophysical Activity 08 Apr 2004

By SpaceRef Editor
April 8, 2004
Filed under , ,

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

Updated 2004 Apr 08 2210 UTC

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 099 Issued at 2200Z on 08 Apr 2004

IA. Analysis of Solar Active Regions and Activity from 07/2100Z
to 08/2100Z: Solar activity was low. Region 588 (S16W13) produced a
C7/Sf flare at 08/1019Z. This event had an associated tenflare (190
sfu) and a full halo CME on LASCO imagery. No significant changes
were observed in Region 588, which maintains a reverse polarity
beta magnetic configuration. Coronal mass ejections were also
observed to originate from behind the northwest limb. The first of
these CMEs occurred at 08/0148Z and had an associated Type II radio
sweep (709 km/s). A long duration x-ray enhancement accompanied the
second CME at around 08/1900Z. No other significant changes or
activity were observed.

IB. Solar Activity Forecast: Solar activity is expected to continue
at low levels. Region 588 is expected to produce occasional C-class

IIA. Geophysical Activity Summary 07/2100Z to 08/2100Z:
The geomagnetic field was mostly quiet to active with isolated minor
storm periods during local nighttime hours.

IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to range from quiet to minor storming. There has been no
obvious transient passage at ACE yet from the full halo CME observed
on LASCO imagery on 6 April. Occasional minor storm periods are
expected in the next 24 hours from this CME. Another full halo CME
was observed today and is expected to produce active to minor storm
periods on 11 April.

III. Event Probabilities 09 Apr-11 Apr

  • Class M 15/15/10
  • Class X 01/01/01
  • Proton 01/01/01
  • PCAF green

IV. Penticton 10.7 cm Flux

  • Observed 08 Apr 094
  • Predicted 09 Apr-11 Apr 095/095/095
  • 90 Day Mean 08 Apr 110

V. Geomagnetic A Indices

  • Observed Afr/Ap 07 Apr 007/010
  • Estimated Afr/Ap 08 Apr 022/030
  • Predicted Afr/Ap 09 Apr-11 Apr 020/030-015/020-020/030

VI. Geomagnetic Activity Probabilities 09 Apr-11 Apr

A. Middle Latitudes

  • Active 40/30/40
  • Minor storm 30/20/30
  • Major-severe storm 15/10/15

B. High Latitudes

  • Active 45/40/45
  • Minor storm 35/30/35
  • Major-severe storm 20/15/20

SpaceRef staff editor.