Report of Solar Geophysical Activity

 

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 110 Issued at 2200Z on 20 Apr 2015

IA.  Analysis of Solar Active Regions and Activity from 19/2100Z to
20/2100Z: Solar activity has been at low levels for the past 24 hours.
The largest solar event of the period was a C1 event observed at
20/1954Z. There are currently 8 numbered sunspot regions on the disk.
IB.  Solar Activity Forecast: Solar activity is expected to be low with
a slight chance for an M-class flare on days one, two, and three (21
Apr, 22 Apr, 23 Apr).

IIA.  Geophysical Activity Summary 19/2100Z to 20/2100Z: The geomagnetic
field has been at quiet to unsettled levels for the past 24 hours. Solar
wind speed, as measured by the ACE spacecraft, reached a peak speed of
437 km/s at 20/2100Z. Total IMF reached 13 nT at 20/2042Z. The maximum
southward component of Bz reached -5 nT at 20/0850Z. Electrons greater
than 2 MeV at geosynchronous orbit reached a peak level of 2619 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at unsettled to minor storm levels on days one and two (21 Apr, 22
Apr) and quiet to active levels on day three (23 Apr).

III.  Event probabilities 21 Apr-23 Apr
Class M    15/15/15
Class X    01/01/01
Proton     01/01/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           20 Apr 150
Predicted   21 Apr-23 Apr 150/155/155
90 Day Mean        20 Apr 130

V.  Geomagnetic A Indices
Observed Afr/Ap 19 Apr  009/009
Estimated Afr/Ap 20 Apr  010/012
Predicted Afr/Ap 21 Apr-23 Apr  024/035-022/027-011/012

VI.  Geomagnetic Activity Probabilities 21 Apr-23 Apr
A.  Middle Latitudes
Active                45/45/30
Minor Storm           35/25/05
Major-severe storm    10/05/01
B.  High Latitudes
Active                05/05/15
Minor Storm           20/20/30
Major-severe storm    75/65/35
Radio Events Observed 20 Apr 2015
A.  245 MHz Bursts
No 245 MHz Burst Observed.
B.  245 MHz Noise Storms
No 245 MHz Noise Storms Observed.
CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1000pfu
Continuation of Serial Number: 2176
Begin Time: 2015 Apr 16 1330 UTC
Yesterday Maximum 2MeV Flux: 2619 pfu
For current space weather conditions please refer to:

www.swpc.noaa.gov/phenomena/solar-radiation-storm

www.sec.noaa.gov/NOAAscales