Report of Solar Geophysical Activity

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 362 Issued at 2200Z on 28 Dec 2015

IA.  Analysis of Solar Active Regions and Activity from 27/2100Z to
28/2100Z: Solar activity has been at moderate levels for the past 24
hours. The largest solar event of the period was an M1 event observed at
28/1245Z from Region 2473 (S22W19). There are currently 2 numbered
sunspot regions on the disk.
IB.  Solar Activity Forecast: Solar activity is expected to be low with
a chance for M-class flares and a slight chance for an X-class flare on
days one, two, and three (29 Dec, 30 Dec, 31 Dec).

IIA.  Geophysical Activity Summary 27/2100Z to 28/2100Z: The geomagnetic
field has been at quiet levels for the past 24 hours. Solar wind speed,
as measured by the ACE spacecraft, reached a peak speed of 548 km/s at
27/2300Z. Electrons greater than 2 MeV at geosynchronous orbit reached a
peak level of 1832 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to unsettled levels on day one (29 Dec), quiet to major
storm levels on day two (30 Dec) and unsettled to minor storm levels on
day three (31 Dec). Protons have a slight chance of crossing threshold
on days one, two, and three (29 Dec, 30 Dec, 31 Dec).

III.  Event probabilities 29 Dec-31 Dec
Class M    50/50/50
Class X    10/10/10
Proton     10/10/10
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           28 Dec 112
Predicted   29 Dec-31 Dec 110/110/110
90 Day Mean        28 Dec 109

V.  Geomagnetic A Indices
Observed Afr/Ap 27 Dec  007/006
Estimated Afr/Ap 28 Dec  007/007
Predicted Afr/Ap 29 Dec-31 Dec  008/010-021/032-015/026

VI.  Geomagnetic Activity Probabilities 29 Dec-31 Dec
A.  Middle Latitudes
Active                20/40/40
Minor Storm           05/25/20
Major-severe storm    01/05/05
B.  High Latitudes
Active                15/10/10
Minor Storm           25/25/25
Major-severe storm    25/60/60

Radio Events Observed 28 Dec 2015
A.  245 MHz Bursts
Start  End   Peak Flux  Time of Peak  Duration
0926   0926    510          0926        0000  
1145   1223    470          1216        0038  
2306   2308    130          2306        0002  
B.  245 MHz Noise Storms
No 245 MHz Noise Storms Observed.

CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1000pfu
Continuation of Serial Number: 2298
Begin Time: 2015 Dec 21 1515 UTC
Yesterday Maximum 2MeV Flux: 1696 pfu