Status Report

Joint USAF/NOAA Report of Solar and Geophysical Activity 01 May 2004

By SpaceRef Editor
May 1, 2004
Filed under , ,

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

Updated 2004 May 01 2210 UTC

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 122 Issued at 2200Z on 01 May 2004

IA. Analysis of Solar Active Regions and Activity from 30/2100Z
to 01/2100Z: Solar activity has been low. There have been several
C-class x-ray events, a C2.8 on 01 May at 0755 UTC, and a C9.5 at
1536 UTC, all from Region 601 (S09W34). This region has grown both
in area and number of spots over the last 24 hours. Region 602
(S13W66) remains steady. Region 603 (S15W37) was numbered today.

IB. Solar Activity Forecast: Solar activity is expected to remain
low. There is an increased chance for an isolated M-class x-ray

IIA. Geophysical Activity Summary 30/2100Z to 01/2100Z:
The geomagnetic field has been at unsettled to active levels. A
combination of southward interplanetary magnetic field (IMF) and
elevated solar wind speeds disrupted the Earth’s magnetic field for
most of 30 April and into 01 May. A transient passage combined with
a solar sector boundary crossing appear to have influenced the
magnetic field earlier on 30 April.

IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to remain at unsettled to active levels for the rest of 01
May. By 02 and 03 May, a high-speed solar wind stream associated
with a coronal hole is expected to intersect the Earth’s magnetic
field. Activity should increase to minor storming late on 02 May
and into early 03 May, dropping back down to active levels by 04 May
as the high-speed stream passes.

III. Event Probabilities 02 May-04 May

  • Class M 20/20/15
  • Class X 01/01/01
  • Proton 05/05/05
  • PCAF green

IV. Penticton 10.7 cm Flux

  • Observed 01 May 094
  • Predicted 02 May-04 May 095/095/095
  • 90 Day Mean 01 May 107

V. Geomagnetic A Indices

  • Observed Afr/Ap 30 Apr 009/012
  • Estimated Afr/Ap 01 May 011/012
  • Predicted Afr/Ap 02 May-04 May 012/015-015/020-012/015

VI. Geomagnetic Activity Probabilities 02 May-04 May

A. Middle Latitudes

  • Active 30/35/30
  • Minor storm 15/20/15
  • Major-severe storm 01/05/01

B. High Latitudes

  • Active 35/40/35
  • Minor storm 20/30/20
  • Major-severe storm 05/10/05

SpaceRef staff editor.