Joint USAF/NOAA Report of Solar and Geophysical Activity 26 July 2010

:Product: Report of Solar-Geophysical Activity
:Issued: 2010 Jul 26 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 207 Issued at 2200Z on 26 Jul 2010
IA. Analysis of Solar Active Regions and Activity from 25/2100Z
to 26/2100Z: Solar activity remained very low. Region 1089 (S24W21)
produced occasional B-class flares as it continued to gradually
decay. Region 1090 (N22E29) and newly numbered Region 1091 (N12W73)
were both simple, single-spot A-type groups.
IB. Solar Activity Forecast: Solar activity is expected to be very
low through the period. However, there is a slight chance for an
isolated C-class flare from Region 1089.
IIA. Geophysical Activity Summary 25/2100Z to 26/2100Z:
Geomagnetic field activity was at quiet levels. Despite the quiet
conditions, Earth remained within a recurrent coronal hole
high-speed wind stream. ACE solar wind readings indicated velocities
varied from 396 to 459 km/s during the period with no discernible
trend.
IIB. Geophysical Activity Forecast: Geomagnetic field activity is
expected to increase to quiet to active levels with a slight chance
for a minor storm on day 1 (27 July) as the current coronal hole
high-speed stream intensifies. Activity is expected to decrease to
quiet to unsettled levels during days 2 – 3 (28 – 29 July) as the
high-speed stream gradually subsides.
III. Event Probabilities 27 Jul-29 Jul
Class M 01/01/01
Class X 01/01/01
Proton 01/01/01
PCAF Green
IV. Penticton 10.7 cm Flux
Observed 26 Jul 084
Predicted 27 Jul-29 Jul 084/084/084
90 Day Mean 26 Jul 075
V. Geomagnetic A Indices
Observed Afr/Ap 25 Jul 005/006
Estimated Afr/Ap 26 Jul 005/009
Predicted Afr/Ap 27 Jul-29 Jul 012/015-008/010-007/008
VI. Geomagnetic Activity Probabilities 27 Jul-29 Jul
A. Middle Latitudes
Active 25/15/10
Minor storm 10/05/01
Major-severe storm 01/01/01
B. High Latitudes
Active 30/20/15
Minor storm 15/05/05
Major-severe storm 05/01/01