Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 23 October 2013

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 296 Issued at 2200Z on 23 Oct 2013

IA. Analysis of Solar Active Regions and Activity from 22/2100Z to
23/2100Z: Solar activity has been at moderate levels for the past 24
hours. The largest solar event of the period was a M4 event observed at
22/2120Z from Region 1875 (N07E04). There are currently 5 numbered
sunspot regions on the disk.

IB. Solar Activity Forecast: Solar activity is expected to be low with
a chance for M-class flares on days one, two, and three (24 Oct, 25 Oct,
26 Oct).

IIA. Geophysical Activity Summary 22/2100Z to 23/2100Z: 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 389 km/s at
23/0440Z. Total IMF reached 7 nT at 22/2118Z. The maximum southward
component of Bz reached -5 nT at 23/0750Z. Electrons greater than 2 MeV
at geosynchronous orbit reached a peak level of 679 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to unsettled levels on days one and three (24 Oct, 26
Oct) and active levels on day two (25 Oct).

III. Event probabilities 24 Oct-26 Oct
Class M 40/40/40
Class X 05/05/05
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 23 Oct 153
Predicted 24 Oct-26 Oct 160/165/160
90 Day Mean 23 Oct 113

V. Geomagnetic A Indices
Observed Afr/Ap 22 Oct 003/004
Estimated Afr/Ap 23 Oct 005/005
Predicted Afr/Ap 24 Oct-26 Oct 013/015-020/025-013/015

VI. Geomagnetic Activity Probabilities 24 Oct-26 Oct
A. Middle Latitudes
Active 30/40/30
Minor Storm 10/15/10
Major-severe storm 01/01/01
B. High Latitudes
Active 15/15/15
Minor Storm 30/20/20
Major-severe storm 40/30/35