Status Report

Joint USAF/NOAA Report of Solar and Geophysical Activity 18 Aug 2005

By SpaceRef Editor
August 19, 2005
Filed under , ,

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

Updated 2005 Aug 18 2204 UTC

Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 230 Issued at 2200Z on 18 Aug 2005

IA. Analysis of Solar Active Regions and Activity from 17/2100Z
to 18/2100Z: Solar activity was very low. Newly numbered Region 799
(S12W56) was responsible for several B-class flares. LASCO imagery
showed a CME at 18/1654 UTC directed towards the southwest which was
likely associated with a B2 flare which occurred from Region 799 at
18/1605 UTC.

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

IIA. Geophysical Activity Summary 17/2100Z to 18/2100Z:
The geomagnetic field was quiet to active due to the continued
influence of a coronal hole high speed stream. Solar wind speed at
ACE has gradually decreased from approximately 700 km/s to 620 km/s.
The greater than 2 MeV electron flux at geosynchronous orbit reached
high levels today.

IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be quiet to unsettled with a chance of isolated active
periods on 19 August as the coronal hole high speed stream moves out
of geoeffective position. Quiet to unsettled conditions are expected
on 20 – 21 August.

III. Event Probabilities 19 Aug-21 Aug

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

IV. Penticton 10.7 cm Flux

  • Observed 18 Aug 083
  • Predicted 19 Aug-21 Aug 085/085/085
  • 90 Day Mean 18 Aug 093

V. Geomagnetic A Indices

  • Observed Afr/Ap 17 Aug 011/018
  • Estimated Afr/Ap 18 Aug 010/015
  • Predicted Afr/Ap 19 Aug-21 Aug 008/010-004/007-004/007

VI. Geomagnetic Activity Probabilities 19 Aug-21 Aug

A. Middle Latitudes

  • Active 20/15/15
  • Minor storm 10/05/05
  • Major-severe storm 01/01/01

B. High Latitudes

  • Active 25/20/20
  • Minor storm 10/10/10
  • Major-severe storm 01/01/01

SpaceRef staff editor.