Status Report

Joint USAF/NOAA Report of Solar and Geophysical Activity 28 May 2008

By SpaceRef Editor

May 28, 2008

Filed under Earth, Space Weather Prediction Center (NOAA), Space Weather Solar-Geophysical Activity, US

Product: Report of Solar-Geophysical Activity
Issued: 2008 May 28 2200 UTC
Prepared jointly by the U.S. Dept. of Commerce, NOAA,
Space Weather Prediction Center and the U.S. Air Force.

Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 149 Issued at 2200Z on 28 May 2008

IA. Analysis of Solar Active Regions and Activity from 27/2100Z to 28/2100Z: Solar activity was at very low levels. The visible disk remained spotless.

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

IIA. Geophysical Activity Summary 27/2100Z to 28/2100Z: The geomagnetic field was at mostly unsettled levels today. At about 27/2200Z, the ACE satellite detected a Solar Sector Boundary crossing from a negative (toward) orientation to a positive (away) orientation. At about 28/0130Z, a shock was detected at ACE with subsequent sharp increases in both density and wind speed, indicative of a co-rotating interaction region (CIR). The CIR was followed by the onset of a high speed stream at about 28/0500Z; solar wind velocities increased to about 525 km/s by the end of the summary period. The greater than 2 MeV electron flux at geosynchronous orbit reached high levels for a brief period today.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to unsettled levels, with a chance for isolated active periods, during all three days of the forecast period (29 May to 31 May) due to the high speed stream.

III. Event Probabilities 29 May-31 May