Status Report

Joint USAF/NOAA Report of Solar and Geophysical Activity 28 Jan 2004

By SpaceRef Editor
January 28, 2004
Filed under , ,

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

Updated 2004 Jan 28 2210 UTC

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 028 Issued at 2200Z on 28 Jan 2004

IA. Analysis of Solar Active Regions and Activity from 27/2100Z
to 28/2100Z: Solar activity was very low. There were no flares in
the past 24 hours. The solar disk was devoid of spots for most of
the day, but towards the end of the period there was evidence for a
new active region (or regions) rotating on the disk at latitudes
S10-S15, near the location where old Region 536 would be expected.

IB. Solar Activity Forecast: Solar activity is expected to be very
low. There should be a slow rise in background levels as the new
active region (or regions) rotate into view.

IIA. Geophysical Activity Summary 27/2100Z to 28/2100Z:
The geomagnetic field ranged from unsettled to minor storm levels.
Solar wind velocity showed a gradual increase beginning around 0100
UTC, and this was accompanied by frequent fluctuations in the
interplanetary Bz component in the range of about -7 nT to +7 nT.
These signatures together with a consistent ‘away’ polarity in the
solar phi angle all suggest that the activity was driven by
favorably positioned positive polarity coronal hole. The greater
than 2 MeV electron fluxes were at high levels during the past 24

IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be unsettled with occasional active periods for the next
two days (29-30 January). An increase to unsettled to active is
expected on the third day (31 January) as another coronal hole
rotates into favorable position.

III. Event Probabilities 29 Jan-31 Jan

  • Class M 01/01/01
  • Class X 01/01/01
  • Proton 01/01/01
  • PCAF Green

IV. Penticton 10.7 cm Flux

  • Observed 28 Jan 089
  • Predicted 29 Jan-31 Jan 100/105/105
  • 90 Day Mean 28 Jan 126

V. Geomagnetic A Indices

  • Observed Afr/Ap 27 Jan 013/016
  • Estimated Afr/Ap 28 Jan 015/019
  • Predicted Afr/Ap 29 Jan-31 Jan 010/015-010/015-010/020

VI. Geomagnetic Activity Probabilities 29 Jan-31 Jan

A. Middle Latitudes

  • Active 25/25/25
  • Minor storm 15/15/15
  • Major-severe storm 05/05/05

B. High Latitudes

  • Active 30/30/30
  • Minor storm 20/20/20
  • Major-severe storm 05/05/05

SpaceRef staff editor.