Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 24 July 2015

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast

SDF Number 205 Issued at 2200Z on 24 Jul 2015

IA. Analysis of Solar Active Regions and Activity from 23/2100Z to 24/2100Z: Solar activity has been at low levels for the past 24 hours. The largest solar event of the period was a C2 event observed at 24/1755Z from Region 2389 (S11E62). There are currently 4 numbered sunspot regions on the disk.

IB. Solar Activity Forecast: Solar activity is expected to be very low with a chance for a C-class flares on days one, two, and three (25 Jul, 26 Jul, 27 Jul).

IIA. Geophysical Activity Summary 23/2100Z to 24/2100Z: 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 539 km/s at 24/0354Z. Total IMF reached 8 nT at 23/2226Z. The maximum southward component of Bz reached -6 nT at 23/2215Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 188 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to active levels on day one (25 Jul), quiet to unsettled levels on day two (26 Jul) and quiet levels on day three (27 Jul).

III. Event probabilities 25 Jul-27 Jul
Class M 01/01/05
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 24 Jul 092
Predicted 25 Jul-27 Jul 095/100/105
90 Day Mean 24 Jul 118

V. Geomagnetic A Indices
Observed Afr/Ap 23 Jul 021/022
Estimated Afr/Ap 24 Jul 008/011
Predicted Afr/Ap 25 Jul-27 Jul 011/012-009/008-006/005

VI. Geomagnetic Activity Probabilities 25 Jul-27 Jul
A. Middle Latitudes
Active 20/10/05
Minor Storm 05/01/01
Major-severe storm 01/01/01
B. High Latitudes
Active 15/20/15
Minor Storm 30/30/20
Major-severe storm 25/15/10