Joint USAF/NOAA Report of Solar and Geophysical Activity 20 July 2011

:Product: Report of Solar-Geophysical Activity
:Issued: 2011 Jul 20 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 201 Issued at 2200Z on 20 Jul 2011
IA. Analysis of Solar Active Regions and Activity from 19/2100Z
to 20/2100Z: Solar activity was very low. There were five numbered
active regions today, but most remained quiet and stable. Regions
1254 (S22W17) and 1259 (N25E42) were classified as Cso Beta groups.
Only 1254 produced any x-ray events during the period, the largest a
B8 flare at 20/1551Z.
IB. Solar Activity Forecast: Solar activity is expected to be very
low to low with the chance for a C-class event for the next 3 days
(21-23 July).
IIA. Geophysical Activity Summary 19/2100Z to 20/2100Z:
The geomagnetic field was mostly unsettled to active during the
period. 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 mostly unsettled to active for the next 3 days (21-23
July), with an isolated minor storm possible at high latitudes. This
activity is forecast as the result of high speed stream effects from
a currently geoeffective coronal hole.
III. Event Probabilities 21 Jul-23 Jul
Class M 01/01/01
Class X 01/01/01
Proton 01/01/01
PCAF green
IV. Penticton 10.7 cm Flux
Observed 20 Jul 100
Predicted 21 Jul-23 Jul 100/100/100
90 Day Mean 20 Jul 097
V. Geomagnetic A Indices
Observed Afr/Ap 19 Jul 010/018
Estimated Afr/Ap 20 Jul 016/018
Predicted Afr/Ap 21 Jul-23 Jul 018/015-014/012-007/008
VI. Geomagnetic Activity Probabilities 21 Jul-23 Jul
A. Middle Latitudes
Active 40/40/30
Minor storm 30/30/10
Major-severe storm 01/01/01
B. High Latitudes
Active 50/50/40
Minor storm 40/40/20
Major-severe storm 10/05/01