IA. Analysis of Solar Active Regions and Activity from 19/2100Z
to 20/2100Z: Solar activity was very low. Region 991 (S10E15)
decayed to a spotless plage.
IB. Solar Activity Forecast: Solar activity is expected to remain
very low.
IIA. Geophysical Activity Summary 19/2100Z to 20/2100Z:
The geomagnetic field was quiet to unsettled.
IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to begin mostly quiet, increasing to unsettled to active
on the second and third days of the forecast period as a recurrent
coronal hole high speed stream becomes geoeffective. There is a
chance geomagnetic field activity will reach minor storm levels at
high latitudes.
III. Event Probabilities 21 Apr-23 Apr
Class M 01/01/01
Class X 01/01/01
Proton 01/01/01
PCAF Green
IV. Penticton 10.7 cm Flux
Observed 20 Apr 071
Predicted 21 Apr-23 Apr 075/080/080
90 Day Mean 20 Apr 072
V. Geomagnetic A Indices
Observed Afr/Ap 19 Apr 006/005
Estimated Afr/Ap 20 Apr 005/005
Predicted Afr/Ap 21 Apr-23 Apr 005/005-008/008-015/015
VI. Geomagnetic Activity Probabilities 21 Apr-23 Apr
A. Middle Latitudes
Active 10/20/25
Minor storm 05/10/15
Major-severe storm 01/05/10
B. High Latitudes
Active 10/25/30
Minor storm 05/10/15
Major-severe storm 01/05/10
 

NOAA Space Weather Scale descriptions can be found at www.sec.noaa.gov/NOAAscales