Joint USAF/NOAA Report of Solar and Geophysical Activity 24 July 2011

:Product: Report of Solar-Geophysical Activity
:Issued: 2011 Jul 24 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 205 Issued at 2200Z on 24 Jul 2011
IA. Analysis of Solar Active Regions and Activity from 23/2100Z
to 24/2100Z: Solar activity was very low during the past 24 hours.
New region 1260 (N20E71) was numbered today, and is initially
classified as an Axx type spot group. Region 1254 (S23W67) and
Region 1259 (N25W10) both decreased in area and remained quiet.
IB. Solar Activity Forecast: Solar activity is expected to be very
low with a slight chance for C-class activity for the next three
days (25-27 July).
IIA. Geophysical Activity Summary 23/2100Z to 24/2100Z:
The geomagnetic field was quiet during the past 24 hours. Solar wind
data observed at the ACE spacecraft indicated a continued decrease
in solar wind velocity to about 400 km/s. 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 one (25 July). Quiet to unsettled with a
slight chance for isolated active conditions are expected on days
two and three (26-27). The activity is forecast due to the expected
arrival of a coronal hole high speed stream.
III. Event Probabilities 25 Jul-27 Jul
Class M 01/01/01
Class X 01/01/01
Proton 01/01/01
PCAF green
IV. Penticton 10.7 cm Flux
Observed 24 Jul 086
Predicted 25 Jul-27 Jul 085/084/084
90 Day Mean 24 Jul 095
V. Geomagnetic A Indices
Observed Afr/Ap 23 Jul 006/008
Estimated Afr/Ap 24 Jul 004/005
Predicted Afr/Ap 25 Jul-27 Jul 005/005-009/009-007/007
VI. Geomagnetic Activity Probabilities 25 Jul-27 Jul
A. Middle Latitudes
Active 05/15/10
Minor storm 01/05/05
Major-severe storm 01/01/01
B. High Latitudes
Active 10/15/10
Minor storm 05/05/05
Major-severe storm 01/01/01