Joint USAF/NOAA Report of Solar and Geophysical Activity 20 October 2012

:Product: Report of Solar-Geophysical Activity
:Issued: 2012 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 294 Issued at 2200Z on 20 Oct 2012
IA. Analysis of Solar Active Regions and Activity from 19/2100Z
to 20/2100Z: Solar activity was high. An impulsive M9 flare
occurred at 20/1814Z from newly numbered Region 1598 (S15E82). This
region appeared to be responsible for several C-class flares as it
approached the visible disk and will continue to be the area of
interest for the next few days. An associated Type II radio sweep
was recorded with an estimated speed of 516 km/s. Region 1593
(N15E09) showed some shearing and spot loss over the past 24 hours,
while Region 1597 (S22W58) had some intermediate spot growth and
separation between leader and follower. The remaining regions
showed little to or no changes. No Earth-directed CMEs were
observed for the past 24 hours.
IB. Solar Activity Forecast: Solar activity is expected to be low
for the next three days (21-23 October) with a chance for isolated
M-class flares.
IIA. Geophysical Activity Summary 19/2100Z to 20/2100Z:
The geomagnetic field was quiet over the past 24 hours. Solar wind
speed, as measured at the ACE spacecraft, steadily decreased from
approximately 440 km/s to near 380 km/s. The Bz component of the
interplanetary magnetic field continued to show minor deflections of
+/- 2 nT while total fields hovered near 4 nT. The greater than 2
MeV electron flux at geosynchronous orbit was at high levels
throughout the period.
IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be quiet on day 1 (21 October). An increase to quiet to
unsettled levels is expected for days 2 and 3 (22-23 October) due to
the effects of a weak coronal hole high speed stream.
III. Event Probabilities 21 Oct-23 Oct
Class M 40/40/40
Class X 10/10/10
Proton 05/05/05
PCAF green
IV. Penticton 10.7 cm Flux
Observed 20 Oct 151
Predicted 21 Oct-23 Oct 150/150/145
90 Day Mean 20 Oct 120
V. Geomagnetic A Indices
Observed Afr/Ap 19 Oct 003/002
Estimated Afr/Ap 20 Oct 003/004
Predicted Afr/Ap 21 Oct-23 Oct 006/005-007/008-007/008
VI. Geomagnetic Activity Probabilities 21 Oct-23 Oct
A. Middle Latitudes
Active 10/10/10
Minor storm 01/01/01
Major-severe storm 01/01/01
B. High Latitudes
Active 15/20/20
Minor storm 20/25/25
Major-severe storm 10/15/15