Joint USAF/NOAA Report of Solar and Geophysical Activity 11 March 2011

:Product: Report of Solar-Geophysical Activity
:Issued: 2011 Mar 11 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 070 Issued at 2200Z on 11 Mar 2011
IA. Analysis of Solar Active Regions and Activity from 10/2100Z
to 11/2100Z: Solar activity was moderate. A single M1 flare was
observed from Region 1166 (N09W39) at 10/2241Z. Region 1166
decreased in area while the number of spots increased. It was
classified as an Ekc type sunspot group with Beta-Gamma-Delta
magnetic characteristics. Region 1169 (N20W09) grew in both area
and spot count, ending the period as an Eki type sunspot group with
Beta-Gamma magnetic characteristics. New Region 1172 (N11E72)
rotated onto the visible solar disk as a bi-polar sunspot group.
IB. Solar Activity Forecast: Solar activity is expected to remain
moderate for the next three days (11-13 March).
IIA. Geophysical Activity Summary 10/2100Z to 11/2100Z:
The geomagnetic field ranged from quiet to active levels at
mid-latitudes with minor to major storm levels observed at high
latitudes. The ACE spacecraft indicated the Bz component of the
interplanetary magnetic field was primarily southward for most of
the period, averaging -6 nT with a maximum of -12 nT, leading to the
disturbed geomagnetic conditions. Solar wind speed averaged 400
km/s during the period.
IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be unsettled to active for the next three days (11-13
March) with a slight chance for minor to major storm conditions,
particularly at high latitudes. Effects from the 07 March CME will
slowly subside during day one (11 March), but the arrival of a
coronal hole high speed stream is expected to become geoeffective
late on day two (12 March) through day three (13 March).
III. Event Probabilities 12 Mar-14 Mar
Class M 50/50/50
Class X 05/05/05
Proton 01/01/01
PCAF green
IV. Penticton 10.7 cm Flux
Observed 11 Mar 123
Predicted 12 Mar-14 Mar 125/125/125
90 Day Mean 11 Mar 093
V. Geomagnetic A Indices
Observed Afr/Ap 10 Mar 014/020
Estimated Afr/Ap 11 Mar 018/035
Predicted Afr/Ap 12 Mar-14 Mar 010/018-010/010-008/008
VI. Geomagnetic Activity Probabilities 12 Mar-14 Mar
A. Middle Latitudes
Active 15/20/15
Minor storm 10/15/10
Major-severe storm 05/05/05
B. High Latitudes
Active 35/20/30
Minor storm 10/15/10
Major-severe storm 01/10/10