Status Report

Joint USAF/NOAA Report of Solar and Geophysical Activity 30 Apr 2004

By SpaceRef Editor
April 30, 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 30 2200 UTC

Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 121 Issued at 2200Z on 30 Apr 2004

IA. Analysis of Solar Active Regions and Activity from 29/2100Z
to 30/2100Z: Solar activity has been low. Newly numbered Region 602
(S14W53) generated a single C-class x-ray event on 30 April at 0547
UTC. Region 599 (N17W41) continues to decay in both area and number
of spots. Along with Region 602, Region 601 (S09W20) was newly
numbered today.

IB. Solar Activity Forecast: Solar activity is expected to remain
very low to low.

IIA. Geophysical Activity Summary 29/2100Z to 30/2100Z:
The geomagnetic field has been at quiet to unsettled levels.
Portions of a solar wind transient associated with a C3.1 x-ray
event on 27 April likely elevated magnetic activity early on the
30th of April, but subsided to quiet levels by 1200 UTC.

IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be quiet from 30 April through 02 May, rising to
unsettled by 03 May. A high speed solar wind stream associated with
a coronal hole is expected to impact the magnetic field by 03 May.

III. Event Probabilities 01 May-03 May

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

IV. Penticton 10.7 cm Flux

  • Observed 30 Apr 089
  • Predicted 01 May-03 May 090/090/095
  • 90 Day Mean 30 Apr 107

V. Geomagnetic A Indices

  • Observed Afr/Ap 29 Apr 003/004
  • Estimated Afr/Ap 30 Apr 008/009
  • Predicted Afr/Ap 01 May-03 May 008/012-010/015-015/020

VI. Geomagnetic Activity Probabilities 01 May-03 May

A. Middle Latitudes

  • Active 25/25/35
  • Minor storm 10/15/25
  • Major-severe storm 01/01/05

B. High Latitudes

  • Active 30/35/35
  • Minor storm 15/15/25
  • Major-severe storm 05/05/10

SpaceRef staff editor.