Status Report

Joint USAF/NOAA Report of Solar and Geophysical Activity 16 Jul 2004

By SpaceRef Editor
July 16, 2004
Filed under , ,

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

Updated 2004 Jul 16 2210 UTC

Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 198 Issued at 2200Z on 16 Jul 2004

IA. Analysis of Solar Active Regions and Activity from 15/2100Z
to 16/2100Z: Solar activity was high. Region 649 (S10E26) produced
three X-class flares: an X1 at 0206 UTC, an X1/1f at 1041 UTC, and
an X3/3b at 1355 UTC. All of these events were impulsive and none
were associated with an obvious CME in the LASCO data. However, a
weak type II radio sweep was observed in association with the X3
event. Region 649 has shown some consolidation of spots in the
leader and in the trailer areas and the region is maintaining
complexity – the delta configuration in the dominant trailer
penumbra continues to be the primary location for the flare
activity. Two new regions are just visible on the east limb in
GOES-12 SXI images at S11 and N05. The region to the north rotated
into view at (N05E88) and was assigned SWO region number 652.

IB. Solar Activity Forecast: Solar activity is expected to be
moderate to high. Region 649 is expected to continue to produce
M-class flares and has a fair chance for producing more major flare
activity during the next three days (17-19 July). These events could
become geoeffective (i.e. earthward directed CMEs or proton events)
as the region evolves and as it moves near central meridian and into
the western hemisphere.

IIA. Geophysical Activity Summary 15/2100Z to 16/2100Z:
The geomagnetic field was mostly quiet to unsettled, although there
was one active period from 2100-2359 on 15 July.

IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be mostly unsettled for the next three days (17-19
July). As noted previously, however, there is a possibility that
Region 649 could produce some events that could increase geomagnetic
activity during the forecast interval.

III. Event Probabilities 17 Jul-19 Jul

  • Class M 75/75/75
  • Class X 35/35/35
  • Proton 15/20/25
  • PCAF Green

IV. Penticton 10.7 cm Flux

  • Observed 16 Jul 147
  • Predicted 17 Jul-19 Jul 150/150/150
  • 90 Day Mean 16 Jul 098

V. Geomagnetic A Indices

  • Observed Afr/Ap 15 Jul 007/009
  • Estimated Afr/Ap 16 Jul 010/010
  • Predicted Afr/Ap 17 Jul-19 Jul 010/012-008/012-008/012

VI. Geomagnetic Activity Probabilities 17 Jul-19 Jul

A. Middle Latitudes

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

B. High Latitudes

  • Active 30/30/30
  • Minor storm 15/15/15
  • Major-severe storm 05/05/05

SpaceRef staff editor.