Status Report

Joint USAF/NOAA Report of Solar and Geophysical Activity 13 October 2012

By SpaceRef Editor
October 13, 2012
Filed under , , ,

:Product: Report of Solar-Geophysical Activity
:Issued: 2012 Oct 13 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 287 Issued at 2200Z on 13 Oct 2012
IA. Analysis of Solar Active Regions and Activity from 12/2100Z
to 13/2100Z: Solar activity was very low. Region 1589 (N13E22) is
the most magnetically complex spot group on the visible disk with a
Beta-Gamma-Delta magnetic configuration. No Earth-directed CMEs
were observed during the reporting period.
IB. Solar Activity Forecast: Solar activity is expected to be low
with a chance for M-class flares and a slight chance for X-class
flares during the forecast period (14-16 October).
IIA. Geophysical Activity Summary 12/2100Z to 13/2100Z:
The geomagnetic field ranged from quiet to minor storm levels with
major to severe storm periods observed at high latitudes. The
period began with quiet to unsettled conditions through 13/0300Z. A
sustained period of southward Bz to -11 nT for approximately 13
hours resulted in active to minor storm conditions with major to
severe storm periods at high latitudes. At about 13/0650Z, the phi
angle changed from a negative (toward) orientation to a positive
(away) orientation, indicating a solar sector boundary crossing.
This was followed by increases in density, temperature, and solar
wind speed indicative of a co-rotating interaction region in advance
of a coronal hole high speed stream (CH HSS). By 13/1618Z, solar
wind speed increased from approximately 530 km/s to 590 km/s while
the total magnetic field (Bt) decreased to 5 nT as the CH HSS became
geoeffective. The greater than 2 MeV electron flux at geosynchronous
orbit reached high levels during the period.
IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to continue at unsettled to active levels with a chance for
isolated minor storm periods on day 1 (14 October). Mostly
unsettled conditions are expected on day 2 (15 October) due to
persistence. By day 3 (16 October), quiet to unsettled conditions
are expected as coronal hole effects wane. On days 2-3, there is a
slight chance for a greater than 10 MeV proton event at
geosynchronous orbit as Region 1589 rotates into a more geoeffective
III. Event Probabilities 14 Oct-16 Oct
Class M 35/35/35
Class X 10/10/10
Proton 05/10/10
PCAF green
IV. Penticton 10.7 cm Flux
Observed 13 Oct 125
Predicted 14 Oct-16 Oct 125/130/130
90 Day Mean 13 Oct 117
V. Geomagnetic A Indices
Observed Afr/Ap 12 Oct 012/014
Estimated Afr/Ap 13 Oct 025/036
Predicted Afr/Ap 14 Oct-16 Oct 016/018-011/012-007/010
VI. Geomagnetic Activity Probabilities 14 Oct-16 Oct
A. Middle Latitudes
Active 30/30/15
Minor storm 20/10/05
Major-severe storm 05/01/01
B. High Latitudes
Active 10/15/15
Minor storm 25/30/20
Major-severe storm 55/40/20

SpaceRef staff editor.