Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 27 October 2013

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 300 Issued at 2200Z on 27 Oct 2013

IA. Analysis of Solar Active Regions and Activity from 26/2100Z to
27/2100Z: Solar activity has been at moderate levels for the past 24
hours. The largest solar event of the period was a M3 event observed at
27/1248Z from Region 1875 (N07W64). 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 (28 Oct, 29
Oct, 30 Oct).

IIA. Geophysical Activity Summary 26/2100Z to 27/2100Z: 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 313 km/s at
26/2148Z. Total IMF reached 6 nT at 27/0318Z. The maximum southward
component of Bz reached -2 nT at 27/0634Z. Electrons greater than 2 MeV
at geosynchronous orbit reached a peak level of 765 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to minor storm levels on day one (28 Oct), unsettled to
active levels on day two (29 Oct) and quiet to active levels on day
three (30 Oct). Protons have a chance of crossing threshold on days one,
two, and three (28 Oct, 29 Oct, 30 Oct).

III. Event probabilities 28 Oct-30 Oct
Class M 65/65/65
Class X 35/35/35
Proton 25/25/25
PCAF green

IV. Penticton 10.7 cm Flux
Observed 27 Oct 167
Predicted 28 Oct-30 Oct 165/155/150
90 Day Mean 27 Oct 115

V. Geomagnetic A Indices
Observed Afr/Ap 26 Oct 003/001
Estimated Afr/Ap 27 Oct 004/005
Predicted Afr/Ap 28 Oct-30 Oct 014/020-015/018-011/012

VI. Geomagnetic Activity Probabilities 28 Oct-30 Oct
A. Middle Latitudes
Active 50/45/20
Minor Storm 15/10/05
Major-severe storm 01/01/01
B. High Latitudes
Active 20/15/15
Minor Storm 20/20/20
Major-severe storm 20/25/20