Joint USAF/NOAA Report of Solar and Geophysical Activity 20 October 2010

:Product: Report of Solar-Geophysical Activity
:Issued: 2010 Oct 20 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 293 Issued at 2200Z on 20 Oct 2010
IA. Analysis of Solar Active Regions and Activity from 19/2100Z
to 20/2100Z: Solar activity was at low levels. Region 1112 (S20W84)
produced the lone event of the period, a C1.5/Sf at 20/1150Z. The
remaining regions were quiet and unchanged.
IB. Solar Activity Forecast: Solar activity is expected to be
predominately very low all three days of the forecast period (21 –
23 October). A chance for an isolated C-class event exists on day
one (21 October) from departing Region 1112, decaying to a slight
chance of C-class activity on days two and three (22 – 23 October).
IIA. Geophysical Activity Summary 19/2100Z to 20/2100Z:
The geomagnetic field was quiet. Solar wind velocities remained
steady during the period, varying between 420 – 460 km/s while the
Bz component of the interplanetary magnetic field remained
predominately north.
IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be at quiet to unsettled levels, with isolated active
periods on day one (21 October). A small, recurrent coronal hole
high speed stream (CH HSS) is expected to rotate into a geoeffective
position on 21 October. By day two (22 October), field conditions
are expected to be mostly quiet. Late on day three (23 October), a
large, recurrent CH HSS is expected to become geoeffective,
resulting in quiet to active conditions.
III. Event Probabilities 21 Oct-23 Oct
Class M 01/01/01
Class X 01/01/01
Proton 01/01/01
PCAF Green
IV. Penticton 10.7 cm Flux
Observed 20 Oct 084
Predicted 21 Oct-23 Oct 084/083/082
90 Day Mean 20 Oct 081
V. Geomagnetic A Indices
Observed Afr/Ap 19 Oct 007/005
Estimated Afr/Ap 20 Oct 004/005
Predicted Afr/Ap 21 Oct-23 Oct 008/008-005/005-008/010
VI. Geomagnetic Activity Probabilities 21 Oct-23 Oct
A. Middle Latitudes
Active 20/05/20
Minor storm 05/01/05
Major-severe storm 01/01/01
B. High Latitudes
Active 25/10/25
Minor storm 10/01/10
Major-severe storm 01/01/01