Space Weather – 3 day forecast
Prepared jointly by the U.S. Dept. of Commerce, NOAA,
Space Weather Prediction Center and the U.S. Air Force.
Updated 2012 Jul 26 2200 UTC
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 208 Issued at 2200Z on 26 Jul 2012
IA. Analysis of Solar Active Regions and Activity from 25/2100Z
to 26/2100Z: Solar activity was low. The only C-class flare of the
reporting period was a C1 at 26/1953Z from new Region 1532 (S20E67).
New flux emergence was observed in the northwest quadrant and was
numbered as Region 1531 (N15W59).
IB. Solar Activity Forecast: Solar activity is expected to be very
low with a chance for a C-class flare.
IIA. Geophysical Activity Summary 25/2100Z to 26/2100Z:
The geomagnetic field was quiet. The greater than 10 MeV proton
event at geosynchronous orbit that began at 23/1545Z, reached a
maximum flux of 12 pfu at 23/2145Z and ended at 24/1800Z. 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 quiet on day 1 (27 July). By mid to late on day 2
(28 July), a recurrent coronal hole high speed stream (CH HSS) is
expected to become geoeffective causing unsettled to active periods.
Unsettled to active periods are expected on day 3 (29 July) due to
the combined effects of the CH HSS and the 25 July coronal mass
III. Event Probabilities 27 Jul-29 Jul
Class M 05/05/05
Class X 01/01/01
IV. Penticton 10.7 cm Flux
Observed 26 Jul 115
Predicted 27 Jul-29 Jul 115/115/120
90 Day Mean 26 Jul 125
V. Geomagnetic A Indices
Observed Afr/Ap 25 Jul 006/007
Estimated Afr/Ap 26 Jul 000/004
Predicted Afr/Ap 27 Jul-29 Jul 006/005-011/015-015/018
VI. Geomagnetic Activity Probabilities 27 Jul-29 Jul
A. Middle Latitudes
Minor storm 01/10/20
Major-severe storm 01/01/05
B. High Latitudes
Minor storm 10/25/30
Major-severe storm 05/30/50