Report of Solar-Geophysical Activity

Report of Solar-Geophysical Activity
Issued: 2008 Jun 26 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 178 Issued at 2200Z on 26 Jun 2008

IA. Analysis of Solar Active Regions and Activity from 25/2100Z
to 26/2100Z: Solar activity was very low. No flares occurred during
the past 24 hours and the solar disk continues to be spotless.
IB. Solar Activity Forecast: Solar activity is expected to be very
low.
IIA. Geophysical Activity Summary 25/2100Z to 26/2100Z:
The geomagnetic field ranged from quiet to active levels during the
past 24 hours. Conditions were initially unsettled but increased to
predominantly active levels from 0000-1500Z. A particularly notable
substorm was observed between 0900-1200Z, which elevated some high
latitude sites to storm level activity. Activity levels have
declined to quiet to unsettled levels since 1500Z. Solar wind
signatures showed an increase in velocity from initial values of
about 500 km/s to about 650 km/s by 0800Z. Solar wind velocity
continued to be elevated in the 600-650 km/s range through the
remainder of the day. The solar wind observations were all
consistent with a high speed stream from a favorably positioned
coronal hole.
IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be mostly quiet to unsettled with a chance for isolated
active periods for the first day (27 June) while the solar wind
velocity remains elevated. Conditions are expected to decline to
quiet to unsettled levels for the second day (28 June) and
predominantly quiet for the third day (29 June).
III. Event Probabilities 27 Jun-29 Jun
Class M 01/01/01
Class X 01/01/01
Proton 01/01/01
PCAF Green
IV. Penticton 10.7 cm Flux
Observed 26 Jun 065
Predicted 27 Jun-29 Jun 065/065/065
90 Day Mean 26 Jun 069
V. Geomagnetic A Indices
Observed Afr/Ap 25 Jun 010/012
Estimated Afr/Ap 26 Jun 012/015
Predicted Afr/Ap 27 Jun-29 Jun 010/010-007/008-005/005
VI. Geomagnetic Activity Probabilities 27 Jun-29 Jun
A. Middle Latitudes
Active 40/20/10
Minor storm 10/05/01
Major-severe storm 01/01/01
B. High Latitudes
Active 50/25/10
Minor storm 15/10/01
Major-severe storm 05/01/01

For current space weather conditions please refer to:

http://www.sec.noaa.gov/SWN/

http://www.sec.noaa.gov/alerts/

NOAA Space Weather Scale descriptions can be found at www.sec.noaa.gov/NOAAscales