Status Report

Joint USAF/NOAA Report of Solar and Geophysical Activity 12 July 2012

By SpaceRef Editor
July 12, 2012
Filed under , , ,

:Product: Report of Solar-Geophysical Activity
:Issued: 2012 Jul 12 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 194 Issued at 2200Z on 12 Jul 2012
IA. Analysis of Solar Active Regions and Activity from 11/2100Z
to 12/2100Z: Solar activity was high. At 12/1649Z, a long-duration
X1/2b flare was observed from Region 1520 (S16W09). The event was
visible in GONG H-alpha imagery as a bright ribbon flare that
erupted along the region’s long E/W oriented inversion line.
Associated with this event were Type II (1268 km/s) and Type IV
radio emissions along with an 800 sfu Tenflare. Limited satellite
imagery indicated a CME was associated with this event. STEREO
Behind COR2 imagery observed a CME lifting off the west limb, first
visible at 12/1710Z. Further analysis of this CME is ongoing.
During the past 24 hours, Region 1520 grew in both area and spot
count and maintained a complex beta-gamma-delta magnetic
configuration. Region 1521 (S21W21) also grew in area and spot
count and remained a beta-gamma magnetic classification. New
Regions 1522 (N13W21) and 1523 (S27E31) emerged on the disk as
simple bi-polar spot groups.
IB. Solar Activity Forecast: Solar activity is expected to be
moderate with a chance for X-class events for the next three days
(13 – 15 July).
IIA. Geophysical Activity Summary 11/2100Z to 12/2100Z:
The geomagnetic field was at quiet to active levels with isolated
high latitude major storm intervals from 11/0600 – 1200Z. ACE solar
data indicated wind velocities decreased steadily through the period
from 500 km/s to near 400 km/s while the Bz component of the
interplanetary magnetic field did not vary much beyond +/- 5 nT.
The greater than 10 MeV proton flux at geosynchronous orbit exceeded
the 10 pfu event threshold at 12/1835Z. At the time of this report,
flux levels were at 35 pfu and rising. The greater than 100 MeV
flux at geosynchronous orbit was enhanced, but below event threshold
levels of 1 pfu. 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 be at mostly quiet to unsettled levels for day one (13
July). Unsettled to active levels, with isolated minor storm
intervals, are expected on days two and three (14 – 15 July) as
effects from the 12 July CME are expected to become geoeffective.
III. Event Probabilities 13 Jul-15 Jul
Class M 80/80/80
Class X 35/35/35
Proton 99/99/50
PCAF red
IV. Penticton 10.7 cm Flux
Observed 12 Jul 165
Predicted 13 Jul-15 Jul 165/165/165
90 Day Mean 12 Jul 127
V. Geomagnetic A Indices
Observed Afr/Ap 11 Jul 010/012
Estimated Afr/Ap 12 Jul 009/011
Predicted Afr/Ap 13 Jul-15 Jul 006/008-015/018-013/015
VI. Geomagnetic Activity Probabilities 13 Jul-15 Jul
A. Middle Latitudes
Active 20/40/35
Minor storm 05/15/10
Major-severe storm 01/01/01
B. High Latitudes
Active 20/10/15
Minor storm 25/30/30
Major-severe storm 25/55/45

SpaceRef staff editor.