Joint USAF/NOAA Report of Solar and Geophysical Activity 10 March 2011

:Product: Report of Solar-Geophysical Activity
:Issued: 2011 Mar 10 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 069 Issued at 2200Z on 10 Mar 2011
IA. Analysis of Solar Active Regions and Activity from 09/2100Z
to 10/2100Z: Solar activity was high. An X1/2b flare was observed
at 09/2323Z from Region 1166 (N08W26). This region grew slightly
during the period and was classified as an Ekc type sunspot group
with Beta-Gamma magnetic characteristics. Region 1169 (N20E04)
decayed slightly and ended the period as an Eai type group with
Beta-Gamma characteristics. The remainder of the disk was quiet and
stable.
IB. Solar Activity Forecast: Solar activity is expected to be
moderate with a slight chance for an X-class x-ray event from Region
1166 or 1169 for the next three days (11-13 March).
IIA. Geophysical Activity Summary 09/2100Z to 10/2100Z:
The geomagnetic field was unsettled to active at middle latitudes and
briefly reached severe storm levels at high latitudes. The
geomagnetic disturbance was likely caused by the arrival of the 07
March CME. The CME shock was observed at the ACE spacecraft at
approximately 06Z accompanied by a slight increase in wind speed to
360 km/s. The Bz component of the interplanetary magnetic field
turned southward and averaged -9nT from 10/06Z to 10/09Z. The 10
MeV proton greater than 10 pfu event that began 08/0105Z ended at
10/1210Z with a maximum flux of 50 pfu at 08/0800Z.
IIB. Geophysical Activity Forecast: Geomagnetic activity is
expected to be unsettled to active for the next three days with a
slight chance for minor to major storm conditions at high latitudes.
Lingering effects from the CME passage are expected on days one and
two (11-12 March) and a recurrent coronal hole high speed stream is
expected to become geoeffective on day three (13 March).
III. Event Probabilities 11 Mar-13 Mar
Class M 50/50/50
Class X 10/10/10
Proton 05/05/05
PCAF green
IV. Penticton 10.7 cm Flux
Observed 10 Mar 131
Predicted 11 Mar-13 Mar 130/130/125
90 Day Mean 10 Mar 092
V. Geomagnetic A Indices
Observed Afr/Ap 09 Mar 002/004
Estimated Afr/Ap 10 Mar 012/018
Predicted Afr/Ap 11 Mar-13 Mar 010/018-007/010-010/012
VI. Geomagnetic Activity Probabilities 11 Mar-13 Mar
A. Middle Latitudes
Active 25/15/20
Minor storm 15/05/15
Major-severe storm 10/01/10
B. High Latitudes
Active 35/35/30
Minor storm 20/10/15
Major-severe storm 10/01/10