Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 11 May 2013

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 131 Issued at 2200Z on 11 May 2013


IA.  Analysis of Solar Active Regions and Activity from 10/2100Z to
11/2100Z: 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
11/1948Z from Region 1746 (S27E63). There are currently 10 numbered
sunspot regions on the disk.

IB.  Solar Activity Forecast: Solar activity is expected to be low with
a chance for M-class flares on days one, two, and three (12 May, 13 May,
14 May).


IIA.  Geophysical Activity Summary 10/2100Z to 11/2100Z: 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 439 km/s at
10/2122Z. Electrons greater than 2 MeV at geosynchronous orbit reached a
peak level of 551 pfu.

IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to unsettled levels on days one and two (12 May, 13 May)
and quiet levels on day three (14 May).


III.  Event probabilities 12 May-14 May
Class M    45/45/45
Class X    05/05/05
Proton     01/01/01
PCAF       green


IV.  Penticton 10.7 cm Flux
Observed           11 May 137
Predicted   12 May-14 May 130/125/125
90 Day Mean        11 May 117


V.  Geomagnetic A Indices
Observed Afr/Ap 10 May  004/004
Estimated Afr/Ap 11 May  004/005
Predicted Afr/Ap 12 May-14 May  005/008-007/008-003/005


VI.  Geomagnetic Activity Probabilities 12 May-14 May
A.  Middle Latitudes
Active                15/15/10
Minor Storm           05/05/01
Major-severe storm    01/01/01
B.  High Latitudes
Active                15/15/15
Minor Storm           25/25/15
Major-severe storm    25/25/10