:Product: 1221RSGA.txt
:Issued: 2016 Dec 21 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 Solar Geophysical Activity Report and Forecast
SDF Number 356 Issued at 2200Z on 21 Dec 2016

IA.  Analysis of Solar Active Regions and Activity from 20/2100Z to
21/2100Z: Solar activity has been at very low levels for the past 24
hours. There are currently 1 numbered sunspot regions on the disk.
IB.  Solar Activity Forecast: Solar activity is expected to be very low
with a slight chance for a C-class flare on days one, two, and three (22
Dec, 23 Dec, 24 Dec).

IIA.  Geophysical Activity Summary 20/2100Z to 21/2100Z: The geomagnetic
field has been at quiet to major storm levels for the past 24 hours.
Solar wind speed reached a peak of 674 km/s at 21/1251Z. Total IMF
reached 15 nT at 21/1626Z. The maximum southward component of Bz reached
-11 nT at 21/0839Z. Electrons greater than 2 MeV at geosynchronous orbit
reached a peak level of 506 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at active to minor storm levels on day one (22 Dec) and quiet to
active levels on days two and three (23 Dec, 24 Dec).

III.  Event probabilities 22 Dec-24 Dec
Class M    01/01/01
Class X    01/01/01
Proton     01/01/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           21 Dec 075
Predicted   22 Dec-24 Dec 075/080/085
90 Day Mean        21 Dec 081

V.  Geomagnetic A Indices
Observed Afr/Ap 20 Dec  004/004
Estimated Afr/Ap 21 Dec  020/028
Predicted Afr/Ap 22 Dec-24 Dec  020/030-011/012-010/012

VI.  Geomagnetic Activity Probabilities 22 Dec-24 Dec
A.  Middle Latitudes
Active                40/25/25
Minor Storm           25/10/10
Major-severe storm    05/01/01
B.  High Latitudes
Active                10/15/15
Minor Storm           25/25/25
Major-severe storm    60/35/35