Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 27 September 2014

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 270 Issued at 2200Z on 27 Sep 2014

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 M1 event observed at
27/0837Z. There are currently 6 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
(28 Sep, 29 Sep, 30 Sep).

IIA. Geophysical Activity Summary 26/2100Z to 27/2100Z: The geomagnetic
field has been at quiet to active levels for the past 24 hours. Solar
wind speed, as measured by the ACE spacecraft, reached a peak speed of
481 km/s at 27/0306Z. Total IMF reached 7 nT at 27/2035Z. The maximum
southward component of Bz reached -6 nT at 27/0022Z. Electrons greater
than 2 MeV at geosynchronous orbit reached a peak level of 1167 pfu.

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

III. Event probabilities 28 Sep-30 Sep
Class M 65/65/65
Class X 10/10/10
Proton 10/10/10
PCAF green

IV. Penticton 10.7 cm Flux
Observed 27 Sep 181
Predicted 28 Sep-30 Sep 180/185/185
90 Day Mean 27 Sep 135

V. Geomagnetic A Indices
Observed Afr/Ap 26 Sep 012/013
Estimated Afr/Ap 27 Sep 014/016
Predicted Afr/Ap 28 Sep-30 Sep 011/015-011/012-007/010

VI. Geomagnetic Activity Probabilities 28 Sep-30 Sep
A. Middle Latitudes
Active 35/35/25
Minor Storm 15/15/10
Major-severe storm 01/01/01
B. High Latitudes
Active 10/10/15
Minor Storm 30/30/25
Major-severe storm 50/50/35