Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 21 September 2016

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 265 Issued at 2200Z on 21 Sep 2016

IA.  Analysis of Solar Active Regions and Activity from 20/2100Z to 21/2100Z: Solar activity has been at low levels for the past 24 hours. The largest solar event of the period was a C1 event observed at 21/1151Z from Region 2595 (N08W90). There are currently 2 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 (22 Sep, 23 Sep, 24 Sep).

IIA.  Geophysical Activity Summary 20/2100Z to 21/2100Z: The geomagnetic field has been at quiet to active levels for the past 24 hours. Solar wind speed reached a peak of 637 km/s at 21/0537Z. Total IMF reached 5 nT at 21/0155Z. The maximum southward component of Bz reached -4 nT at 20/2315Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 1366 pfu.

IIB.  Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to unsettled levels on days one and two (22 Sep, 23 Sep) and quiet levels on day three (24 Sep).

III.  Event probabilities 22 Sep-24 Sep

Class M    01/01/01

Class X    01/01/01

Proton     01/01/01

PCAF       green

IV.  Penticton 10.7 cm Flux

Observed           21 Sep 086

Predicted   22 Sep-24 Sep 085/085/085

90 Day Mean        21 Sep 086

V.  Geomagnetic A Indices

Observed Afr/Ap 20 Sep  015/018

Estimated Afr/Ap 21 Sep  010/010

Predicted Afr/Ap 22 Sep-24 Sep  007/008-007/008-006/005

VI.  Geomagnetic Activity Probabilities 22 Sep-24 Sep

A.  Middle Latitudes

Active                15/25/10

Minor Storm           01/05/01

Major-severe storm    01/01/01

B.  High Latitudes

Active                15/15/15

Minor Storm           20/30/15

Major-severe storm    20/35/15