Status Report

Joint USAF/NOAA Report of Solar and Geophysical Activity 04 Apr 2008

By SpaceRef Editor

April 4, 2008

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

Product: Report of Solar-Geophysical Activity
Issued: 2008 Apr 04 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 095 Issued at 2200Z on 04 Apr 2008

IA. Analysis of Solar Active Regions and Activity from 03/2100Z to 04/2100Z: Solar activity was very low. Spotless plage Region 989 (S11W54) produced isolated B-class subflares. No new regions were numbered.

IB. Solar Activity Forecast: Solar activity is expected to be very low to low. There is a fair chance for an isolated C-class flare from Region 989.

IIA. Geophysical Activity Summary 03/2100Z to 04/2100Z: Geomagnetic field activity was at quiet to active levels. Field activity increased to active levels during 04/1800 – 2100Z due to increased solar wind velocities and IMF magnitude combined with periods of southward IMF Bz. ACE signatures indicated Earth entered the co-rotating interaction region between slow and fast solar wind flows. Velocities increased to 507 km/sec near the close of the summary period. The greater than 2 MeV electron flux at geosynchronous orbit was high during most of the period.

IIB. Geophysical Activity Forecast: Geomagnetic field activity is expected to be at active levels during days 1 – 2 (05 – 06 April) with minor to major storm periods at high latitudes due to coronal hole effects. Field activity is expected to decrease to unsettled levels on day 3 (07 April) with active to minor storm periods at high latitudes as coronal hole effects decrease.

III. Event Probabilities 05 Apr-07 Apr