Joint USAF/NOAA Report of Solar and Geophysical Activity 9 March 2012

:Product: Report of Solar-Geophysical Activity
:Issued: 2012 Mar 09 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 09 Mar 2012
IA. Analysis of Solar Active Regions and Activity from 08/2100Z
to 09/2100Z: Solar activity reached high levels today. Region 1429
(N18W13) produced an M6 flare at 09/0353Z. Associated with this
event was Type II (1285 km/s) and Type IV radio sweeps along with a
full halo CME first seen in SOHO/LASCO C2 imagery at 09/0426Z. The
CME had an estimated plane-of-sky speed of 850 km/s in STEREO B COR2
imagery. Separation and slight decay within the intermediate area
was observed in Region 1429, however it still remained a large Ekc
spot group with a Beta-Gamma-Delta magnetic configuration. A new
spot group rotated onto the NE limb and was numbered Region 1432
(N18E69). This new region is too close to the limb to accurately
determine the spot and magnetic classification, however it produced
a C9 flare at 09/2025Z.
IB. Solar Activity Forecast: Solar activity is expected to continue
at low to moderate levels with a chance for X-class activity from
Region 1429 for the next three days (10 – 12 March).
IIA. Geophysical Activity Summary 08/2100Z to 09/2100Z:
The geomagnetic field was at active to severe storm conditions due to
continued activity from the sheath region associated with the 07
March CME. At approximately 09/0049Z, the Bz component of the
interplanetary magnetic field started to rotate towards a more
magnetically connected polarity. Bz continued to be negative for
several hours reaching values near -17 nT with an approximate solar
wind speed over 600 km/s. The geomagnetic field responded with
major to severe storm periods during the periods 09/0300 – 1500Z.
Solar wind remained elevated around 600 km/s by the end of the
period. The greater than 10 MeV proton event that began at 07/0510Z
is ongoing. The greater than 100 MeV proton event that began at
07/0405 is ongoing.
IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be under the influence of the current CME through early
on day 1. Unsettled to active conditions, with isolated minor storm
periods, are possible is expected as the CME continues to wane.
Early to mid-day on day 2 (11 March), the CME associated with
today’s M-6 flare is expected to become geoeffective. Active to
severe storm periods are expected with this event. Unsettled to
active conditions, with isolated minor storm periods, are possible
on day 3 (12 March) as conditions are expected to slowly dissipate.
III. Event Probabilities 10 Mar-12 Mar
Class M 80/80/80
Class X 40/40/40
Proton 99/99/60
PCAF red
IV. Penticton 10.7 cm Flux
Observed 09 Mar 146
Predicted 10 Mar-12 Mar 150/150/150
90 Day Mean 09 Mar 125
V. Geomagnetic A Indices
Observed Afr/Ap 08 Mar 021/028
Estimated Afr/Ap 09 Mar 046/073
Predicted Afr/Ap 10 Mar-12 Mar 015/022-033/070-017/030
VI. Geomagnetic Activity Probabilities 10 Mar-12 Mar
A. Middle Latitudes
Active 30/30/30
Minor storm 20/35/20
Major-severe storm 05/20/10
B. High Latitudes
Active 35/20/40
Minor storm 25/30/30
Major-severe storm 15/50/25