Report of Solar-Geophysical Activity

Issued: 2010 Oct 21 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 294 Issued at 2200Z on 21 Oct 2010

IA.  Analysis of Solar Active Regions and Activity from  20/2100Z
to 21/2100Z:  Solar activity was very low. Today's activity consisted
of occasional, low-level B-class flares. Most of these were either
from Region 1112 (S20, behind west limb) or Region 1117 (N23E48),
although at least one event appeared to originate from a new group
just behind the East limb (around N25). Regions 1113 (N16W31) and
1115 (S29W13) were quiet and stable.
IB.  Solar Activity Forecast:  Solar activity is expected to be very
low, although there is a slight chance for an isolated C-class event
during the next three days (22-24 October).
IIA.  Geophysical Activity Summary 20/2100Z to 21/2100Z:
The geomagnetic field was quiet during the past 24 hours.
IIB.  Geophysical Activity Forecast:  The geomagnetic field is
expected to be generally quiet for the first day (22 October) and
about halfway through the second day (23 October). Sometime around
mid-day on 23 October and continuing through the third day (24
October), an increase to unsettled levels with a chance for active
periods is expected. There is also a chance for isolated storm
periods at some locations during this interval. The increase is
forecast because of expected effects from a high speed solar wind
stream from a favorably positioned coronal hole.
III.  Event Probabilities 22 Oct-24 Oct
Class M    01/01/01
Class X    01/01/01
Proton     01/01/01
PCAF       Green
IV.  Penticton 10.7 cm Flux
Observed           21 Oct 084
Predicted   22 Oct-24 Oct  082/082/082
90 Day Mean        21 Oct 081
V.  Geomagnetic A Indices
Observed Afr/Ap 20 Oct  003/004
Estimated Afr/Ap 21 Oct  003/005
Predicted Afr/Ap 22 Oct-24 Oct  005/005-010/010-015/015
VI.  Geomagnetic Activity Probabilities 22 Oct-24 Oct
A.  Middle Latitudes
Active                05/30/40
Minor storm           01/15/20
Major-severe storm    01/05/05
B.  High Latitudes
Active                05/35/45
Minor storm           01/20/25
Major-severe storm    01/10/15

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