Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 26 September 2014

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 269 Issued at 2200Z on 26 Sep 2014

IA. Analysis of Solar Active Regions and Activity from 25/2100Z to
26/2100Z: Solar activity has been at low levels for the past 24 hours.
The largest solar event of the period was a C8 event observed at
26/0544Z from Region 2175 (N16W25). There are currently 8 numbered
sunspot regions on the disk.

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

IIA. Geophysical Activity Summary 25/2100Z to 26/2100Z: The geomagnetic
field has been at quiet to unsettled levels for the past 24 hours. Solar
wind speed, as measured by the ACE spacecraft, reached a peak speed of
494 km/s at 26/1404Z. Total IMF reached 7 nT at 26/0724Z. The maximum
southward component of Bz reached -6 nT at 26/1246Z. Electrons greater
than 2 MeV at geosynchronous orbit reached a peak level of 1093 pfu.

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

III. Event probabilities 27 Sep-29 Sep
Class M 65/65/65
Class X 10/10/10
Proton 10/10/10
PCAF green

IV. Penticton 10.7 cm Flux
Observed 26 Sep 170
Predicted 27 Sep-29 Sep 170/170/175
90 Day Mean 26 Sep 134

V. Geomagnetic A Indices
Observed Afr/Ap 25 Sep 013/012
Estimated Afr/Ap 26 Sep 011/013
Predicted Afr/Ap 27 Sep-29 Sep 011/015-011/015-011/012

VI. Geomagnetic Activity Probabilities 27 Sep-29 Sep
A. Middle Latitudes
Active 35/35/35
Minor Storm 15/15/15
Major-severe storm 01/01/01
B. High Latitudes
Active 10/10/10
Minor Storm 30/30/30
Major-severe storm 50/50/50