Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 26 October 2013

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 299 Issued at 2200Z on 26 Oct 2013

IA. Analysis of Solar Active Regions and Activity from 25/2100Z to
26/2100Z: Solar activity has been at high levels for the past 24 hours.
The largest solar event of the period was a M3 event observed at
26/1927Z from Region 1884 (S09E78). There are currently 9 numbered
sunspot regions on the disk.

IB. Solar Activity Forecast: Solar activity is likely to be moderate
with a chance for X-class flares on days one, two, and three (27 Oct, 28
Oct, 29 Oct).

IIA. Geophysical Activity Summary 25/2100Z to 26/2100Z: 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 324 km/s at
25/2226Z. Electrons greater than 2 MeV at geosynchronous orbit reached a
peak level of 555 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to unsettled levels on day one (27 Oct), quiet to minor
storm levels on day two (28 Oct) and unsettled to active levels on day
three (29 Oct). Protons have a chance of crossing threshold on days one,
two, and three (27 Oct, 28 Oct, 29 Oct).

III. Event probabilities 27 Oct-29 Oct
Class M 65/65/65
Class X 35/35/35
Proton 25/25/25
PCAF green

IV. Penticton 10.7 cm Flux
Observed 26 Oct 165
Predicted 27 Oct-29 Oct 165/165/160
90 Day Mean 26 Oct 115

V. Geomagnetic A Indices
Observed Afr/Ap 25 Oct 003/002
Estimated Afr/Ap 26 Oct 002/003
Predicted Afr/Ap 27 Oct-29 Oct 007/008-014/020-015/018

VI. Geomagnetic Activity Probabilities 27 Oct-29 Oct
A. Middle Latitudes
Active 15/50/35
Minor Storm 05/15/10
Major-severe storm 01/01/01
B. High Latitudes
Active 15/20/15
Minor Storm 20/20/20
Major-severe storm 15/20/25