Status Report

Joint USAF/NOAA Report of Solar and Geophysical Activity 25 January 2012

By SpaceRef Editor
January 25, 2012
Filed under , , ,

:Product: Report of Solar-Geophysical Activity
:Issued: 2012 Jan 25 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 025 Issued at 2200Z on 25 Jan 2012
IA. Analysis of Solar Active Regions and Activity from 24/2100Z
to 25/2100Z: Solar activity was at very low levels. As Regions 1401
(N16W66) and 1402 (N26W60) approached the west limb, they exhibited
little change over the past 24 hours, as did the remainder of the
disk and limb.
IB. Solar Activity Forecast: Solar activity is expected to be very
low to low during the period (26 – 28 January). A chance for
M-class activity exists on 26 – 27 January from Regions 1401 and
1402 before they rotate around the west limb.
IIA. Geophysical Activity Summary 24/2100Z to 25/2100Z:
The geomagnetic field ranged from quiet to minor storm levels with
isolated high latitude major to severe storm intervals. During the
period, ACE solar wind velocities varied between a high of 625 km/s
at the beginning, and steadily decreased to a low of near 500 km/s
by the end. The Bz component of the interplanetary magnetic field
varied between +/- 10 nT through about 25/1000Z and remained weakly
south at -1 to -5 nT through the end of the period. The greater
than 10 MeV proton flux event was still in progress at the time of
this report. Proton flux levels steadily decayed to end the period
near 100 pfu.
IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be at mostly quiet levels on day one (26 January). By
day two (27 January) and through day three (28 January), field
activity is expected to increase to quiet to unsettled levels with
isolated active periods. This increase in activity is due to a
recurrent coronal hole high speed stream expected to move into a
geoeffective position. The greater than 10 MeV proton flux event is
expected to remain above event levels through 26 January, falling to
background levels by 27 January.
III. Event Probabilities 26 Jan-28 Jan
Class M 25/10/01
Class X 01/01/01
Proton 50/01/01
PCAF in progress
IV. Penticton 10.7 cm Flux
Observed 25 Jan 126
Predicted 26 Jan-28 Jan 125/120/120
90 Day Mean 25 Jan 143
V. Geomagnetic A Indices
Observed Afr/Ap 24 Jan 013/024
Estimated Afr/Ap 25 Jan 011/013
Predicted Afr/Ap 26 Jan-28 Jan 005/005-007/008-007/008
VI. Geomagnetic Activity Probabilities 26 Jan-28 Jan
A. Middle Latitudes
Active 10/20/20
Minor storm 01/10/10
Major-severe storm 01/01/01
B. High Latitudes
Active 10/25/25
Minor storm 05/15/15
Major-severe storm 01/05/05

SpaceRef staff editor.