Joint USAF/NOAA Report of Solar and Geophysical Activity 10 March 2012

:Product: Report of Solar-Geophysical Activity
:Issued: 2012 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 070 Issued at 2200Z on 10 Mar 2012
IA. Analysis of Solar Active Regions and Activity from 09/2100Z
to 10/2100Z: Solar activity was high. Region 1430 (N21W42) produced
a C8 flare at 10/1552Z and Region 1429 (N18W26) produced a long
duration M8 flare at 10/1744Z with an associated Tenflare (459 sfu)
and a Type IV radio sweep. Both flares had associated CMEs. The
first CME appeared in SOHO/LASCO C2 imagery at 10/1624Z with
the majority of the ejecta off the NW limb. The second CME,
associated with the M8 flare, first appeared in C2 imagery at
10/1800Z. Further analysis will be done as imagery becomes
available, however initial analysis indicated the event produced a
full-halo CME with an estimated plane-of-sky speed between 1200 –
1400 km/s. Region 1429 remained a large Ekc spot class with a
Beta-Gamma-Delta magnetic class. A new region appeared on the ENE
limb near Region 1432 (N16E52). Close proximity to the limb made a
detailed analysis of this new region difficult.
IB. Solar Activity Forecast: Solar activity is expected to be at
moderate to high levels for the forecast period (11 – 13 March).
IIA. Geophysical Activity Summary 09/2100Z to 10/2100Z:
The geomagnetic field was at quiet to minor storm levels with periods
of major storming at higher latitudes between 10/0600 – 1200Z.
Activity was due to the continued effects of the 07 March CME.
Solar wind speed at the ACE spacecraft has gradually decreased from
approximately 580 km/s to near 450 km/s. The greater than 10 MeV
and greater than 100 Mev proton events are on going. The greater
than 2 MeV electron flux at geosynchronous orbit was at high levels
throughout the period.
IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be quiet to unsettled early on day 1 (11 March) until
the arrival of the 09 March CME followed by today’s CME associated
with the M8 flare. Models show an arrival of the first CME early to
midday on 11 March which is expected to cause minor to major storm
conditions with isolated severe storm periods likely. Initial
estimates on the second CME indicate an arrival late on day 1.
Activity is expected to continue into day 2 (12 March) with minor to
major storm conditions with isolated severe storm periods possible.
Conditions are expected to decrease to unsettled to active levels by
day 3 (13 March).
III. Event Probabilities 11 Mar-13 Mar
Class M 80/80/80
Class X 40/40/40
Proton 99/99/60
PCAF red
IV. Penticton 10.7 cm Flux
Observed 10 Mar 149
Predicted 11 Mar-13 Mar 155/155/155
90 Day Mean 10 Mar 125
V. Geomagnetic A Indices
Observed Afr/Ap 09 Mar 057/094
Estimated Afr/Ap 10 Mar 013/018
Predicted Afr/Ap 11 Mar-13 Mar 047/085-024/040-007/012
VI. Geomagnetic Activity Probabilities 11 Mar-13 Mar
A. Middle Latitudes
Active 30/25/15
Minor storm 35/30/05
Major-severe storm 35/25/01
B. High Latitudes
Active 05/15/25
Minor storm 15/25/15
Major-severe storm 75/55/10