Status Report

Joint USAF/NOAA Report of Solar and Geophysical Activity 23 May 2004

By SpaceRef Editor
May 23, 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 23 2210 UTC

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 144 Issued at 2200Z on 23 May 2004

IA. Analysis of Solar Active Regions and Activity from 22/2100Z
to 23/2100Z: Solar activity was low. Region 618 (S10E26) produced
four low-level C-class events during the past 24 hours. The group
continues to grow and is maintaining magnetic complexity with a
delta configuration in the leader spots. New regions 619 (S09W37)
and 620 (S15E34) emerged on the disk today as small sunspot groups.

IB. Solar Activity Forecast: Solar activity is expected to be low
to moderate. There is a fair chance for an M-class event from Region
618, given the continuing growth trend and the magnetic complexity
of the group.

IIA. Geophysical Activity Summary 22/2100Z to 23/2100Z:
The geomagnetic field was mostly unsettled during the past 24 hours.
The high speed solar wind stream continues to persist (similar to
the last 3-4 days) with speeds typically ranging from 450 to 500

IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be quiet to unsettled for the next three days (24-26
May). The currently enhanced solar wind velocity is expected to
decline to nominal levels over the next 24 hours. NOTE: The ACE
spacecraft orbit will bring ACE nearly in line with the Sun from
about May 30 to June 2, 2004. During that time solar radio noise is
expected to interfere with spacecraft telemetry resulting in the
loss of solar wind plasma, magnetic field, and particle data.

III. Event Probabilities 24 May-26 May

  • Class M 50/50/50
  • Class X 10/10/10
  • Proton 05/05/05
  • PCAF green

IV. Penticton 10.7 cm Flux

  • Observed 23 May 104
  • Predicted 24 May-26 May 105/105/100
  • 90 Day Mean 23 May 105

V. Geomagnetic A Indices

  • Observed Afr/Ap 22 May 007/011
  • Estimated Afr/Ap 23 May 010/010
  • Predicted Afr/Ap 24 May-26 May 005/008-007/008-007/008

VI. Geomagnetic Activity Probabilities 24 May-26 May

A. Middle Latitudes

  • Active 20/20/20
  • Minor storm 10/10/10
  • Major-severe storm 05/05/05

B. High Latitudes

  • Active 20/25/25
  • Minor storm 10/10/10
  • Major-severe storm 05/05/05

SpaceRef staff editor.