Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 15 May 2013

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 135 Issued at 2200Z on 15 May 2013


IA.  Analysis of Solar Active Regions and Activity from 14/2100Z to
15/2100Z: Solar activity has been at high levels for the past 24 hours.
The largest solar event of the period was a X1 event observed at
15/0148Z from Region 1748 (N11E51). There are currently 9 numbered
sunspot regions on the disk.

IB.  Solar Activity Forecast: Solar activity is likely to be high on
days one, two, and three (16 May, 17 May, 18 May).


IIA.  Geophysical Activity Summary 14/2100Z to 15/2100Z: 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
457 km/s at 15/1605Z. Total IMF reached 11 nT at 15/1317Z. The maximum
southward component of Bz reached -8 nT at 15/1124Z. Protons greater
than 10 MeV at geosynchronous orbit reached a peak level of 23 pfu at
15/1850Z.

IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to unsettled levels on days one and three (16 May, 18
May) and quiet to active levels on day two (17 May). Protons are
expected to cross threshold on days one, two, and three (16 May, 17 May,
18 May).


III.  Event probabilities 16 May-18 May
Class M    80/80/80
Class X    60/60/60
Proton     99/90/90
PCAF       yellow


IV.  Penticton 10.7 cm Flux
Observed           15 May 146
Predicted   16 May-18 May 145/145/145
90 Day Mean        15 May 120


V.  Geomagnetic A Indices
Observed Afr/Ap 14 May  007/009
Estimated Afr/Ap 15 May  007/010
Predicted Afr/Ap 16 May-18 May  006/008-011/015-008/008


VI.  Geomagnetic Activity Probabilities 16 May-18 May
A.  Middle Latitudes
Active                15/30/15
Minor Storm           05/10/05
Major-severe storm    01/01/01
B.  High Latitudes
Active                15/15/15
Minor Storm           25/30/25
Major-severe storm    25/40/25