:Product: 0405RSGA.txt
:Issued: 2008 Apr 05 2203 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 096 Issued at 2200Z on 05 Apr 2008
IA.  Analysis of Solar Active Regions and Activity from  04/2100Z
to 05/2100Z:  Solar activity was very low. Spotless plage Region 989
(S11W67) produced an isolated low-level B-class flare. SOHO/LASCO
images showed a halo CME, first visible in C2 at 05/1626Z. The CME
appeared to be from the back side, based on STEREO Ahead EUVI 195
images and the GOES- 10 X-ray signature. No new active regions were
numbered.
IB.  Solar Activity Forecast:  Solar activity is expected to be very
low.
IIA.  Geophysical Activity Summary 04/2100Z to 05/2100Z:
Geomagnetic field activity ranged from quiet to major storm levels
with a Kp = 6 observed during 05/1500 - 1800Z. ACE measurements
indicated Earth entered a fast solar wind flow from a recurrent
low-latitude coronal hole in the southern hemisphere. Solar wind
velocities increased during the period with a peak of 671 km/sec
detected at 05/1634Z. IMF Bz reached a minimum of -7 nT at 05/1441Z.
The greater than 2 MeV electron flux at geosynchronous orbit briefly
reached high levels during the period.
IIB.  Geophysical Activity Forecast:  Geomagnetic field activity is
expected to be at unsettled to minor storm levels on day 1 (06
April) with major storm levels possible at high latitudes. Activity
is expected to decrease to unsettled to active levels during days 2
- 3 (07 - 08 April) as coronal hole effects persist.
III.  Event Probabilities 06 Apr-08 Apr
Class M    01/01/01
Class X    01/01/01
Proton     01/01/01
PCAF       green
IV.  Penticton 10.7 cm Flux
Observed           05 Apr 071
Predicted   06 Apr-08 Apr  070/070/070
90 Day Mean        05 Apr 073
V.  Geomagnetic A Indices
Observed Afr/Ap 04 Apr  008/011
Estimated Afr/Ap 05 Apr  015/025
Predicted Afr/Ap 06 Apr-08 Apr  012/020-010/012-010/012
VI.  Geomagnetic Activity Probabilities 06 Apr-08 Apr
A.  Middle Latitudes
Active                30/25/25
Minor storm           10/05/05
Major-severe storm    01/01/01
B.  High Latitudes
Active                50/30/30
Minor storm           25/10/10
Major-severe storm    05/01/01