Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 16 Nov 2012

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 321 Issued at 2200Z on 16 Nov 2012

IA. Analysis of Solar Active Regions and Activity from 15/2100Z to
16/2100Z: Solar activity has been at low levels for the past 24 hours.
The largest solar event of the period was a C8 flare observed at
16/1539Z from the northeast limb. This event was accompanied by a Type
II radio sweep (511 km/s). A long duration C1 flare from Region 1613
(S23W05) occurred at 16/0751Z with an associated 24 degree filament
eruption centered near S39E22 at 16/0720Z. Another filament eruption
was observed from the East limb seen in SDO/AIA 304 imagery beginning at
16/0648 UTC. Analysis of SOHO/LASCO C2 suggested these eruptions would
not be geoeffective.

Yesterday’s general trend of decreasing size and complexity continued
among all active regions, leaving Region 1610 (S22W63) as the only
beta-gamma type group on the visible disk. However, flux emergence was
observed in other portions of the disk. New Region 1617 (S18W18) was
numbered today, and emerging flux was noted near N12E35 on SDO/HMI
magnetogram loops and later reported by Holloman Solar Observatory

There are currently 8 numbered sunspot regions on the disk.

IB. Solar Activity Forecast: Solar activity is expected to be at low
levels with a chance for an isolated moderate event on days one, two,
and three (17 Nov, 18 Nov, 19 Nov).

IIA. Geophysical Activity Summary 15/2100Z to 16/2100Z: The geomagnetic
field has been at quiet levels for the past 24 hours. Solar wind speed
at the ACE spacecraft reached a peak speed of 453 km/s at 16/1112Z, but
generally remained in the low to mid 400 km/s range under the waning
influence of a weak negative coronal hole high speed stream. Bz was
generally -4nT or greater through the period. No significant
discontinuities were observed in the measured variables.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to unsettled levels for the next three days (17 Nov, 18
Nov, 19 Nov). The field is expected to be occasionally unsettled over
the next three days as another coronal hole high speed stream becomes
geoeffective.

III. Event probabilities 17 Nov-19 Nov
Class M 25/25/25
Class X 05/05/05
Proton 05/05/05
PCAF green

IV. Penticton 10.7 cm Flux
Observed 16 Nov 138
Predicted 17 Nov-19 Nov 141/145/145
90 Day Mean 16 Nov 120

V. Geomagnetic A Indices
Observed Afr/Ap 15 Nov 003/003
Estimated Afr/Ap 16 Nov 005/005
Predicted Afr/Ap 17 Nov-19 Nov 008/008-007/008-006/005

VI. Geomagnetic Activity Probabilities 17 Nov-19 Nov
A. Middle Latitudes
Active 20/10/05
Minor Storm 10/05/01
Major-severe storm 01/01/01
B. High Latitudes
Active 15/15/15
Minor Storm 30/20/10
Major-severe storm 35/20/05