Joint USAF/NOAA Report of Solar and Geophysical Activity 18 October 2010

:Product: Report of Solar-Geophysical Activity
:Issued: 2010 Oct 18 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 291 Issued at 2200Z on 18 Oct 2010
IA. Analysis of Solar Active Regions and Activity from 17/2100Z
to 18/2100Z: Solar activity was at low levels. Region 1112 (S19W58)
was responsible for all the period’s activity which included a long
duration C2.5 x-ray event at 18/1643Z. The region decayed slightly
in area and spot count, but maintained a beta-gamma magnetic
configuration. Region 1113 (N18E10) had several point brightenings
observed during the period.
IB. Solar Activity Forecast: Solar activity is expected to remain
at predominately very low to low levels all three days of the
forecast period (19 – 21 October), with a chance for M-class events
from Region 1112.
IIA. Geophysical Activity Summary 17/2100Z to 18/2100Z:
The geomagnetic field was quiet at all latitudes.
IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be at quiet to active levels all three days of the
forecast period (19 – 21 October), with isolated minor storm periods
possible on 19 October. A coronal hole high speed stream (CH HSS) is
expected to rotate into a geoeffective position late on 18 October
or early on 19 October, followed by a second geoeffective CH HSS
expected to arrive early on 20 October. These features, coupled with
possible effects from the CME observed on 14 October, are the
reasons for the forecasted increase in geomagnetic activity.
III. Event Probabilities 19 Oct-21 Oct
Class M 25/25/25
Class X 01/01/01
Proton 01/01/01
PCAF Green
IV. Penticton 10.7 cm Flux
Observed 18 Oct 091
Predicted 19 Oct-21 Oct 090/090/090
90 Day Mean 18 Oct 081
V. Geomagnetic A Indices
Observed Afr/Ap 17 Oct 010/011
Estimated Afr/Ap 18 Oct 004/005
Predicted Afr/Ap 19 Oct-21 Oct 012/012-008/010-008/008
VI. Geomagnetic Activity Probabilities 19 Oct-21 Oct
A. Middle Latitudes
Active 30/20/20
Minor storm 15/05/05
Major-severe storm 01/01/01
B. High Latitudes
Active 35/25/25
Minor storm 20/15/10
Major-severe storm 01/01/01