Joint USAF/NOAA Report of Solar and Geophysical Activity 17 June 2011

:Product: Report of Solar-Geophysical Activity
:Issued: 2011 Jun 17 2200 UTC
# Prepared jointly by the U.S. Dept. of Commerce, NOAA,
# Space Weather Prediction Center and the U.S. Air Force.
#
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 168 Issued at 2200Z on 17 Jun 2011
IA. Analysis of Solar Active Regions and Activity from 16/2100Z
to 17/2100Z: Solar activity decreased to very low levels. Region
1234 (S16W48) and Region 1236 (N17E33) each produced isolated
B-class x-ray flares. A B7 x-ray flare occurred near the SE limb at
17/0646Z. Region 1234 showed a gradual increase in interior spots
during the period and was classified as a Dsi group with a simple
bipolar magnetic structure. Region 1236 showed a gradual decrease in
magnetic complexity in its trailer portion and was classified as a
Dho with a beta-gamma magnetic structure. No new regions were
numbered. No Earth-directed coronal mass ejections (CME) were
observed during the period.
IB. Solar Activity Forecast: Solar activity is expected to be low
through the period (18 – 20 June) with a chance for an isolated
M-class flare.
IIA. Geophysical Activity Summary 16/2100Z to 17/2100Z:
Geomagnetic activity was at quiet to active levels. An active period
was observed during 07/0000 – 0300Z. A geomagnetic sudden impulse
(SI) was observed at Boulder at 17/0244Z (31 nT) and indicated the
arrival of the partial-halo CME observed on 14 June.
IIB. Geophysical Activity Forecast: Geomagnetic activity is
expected to be at quiet to unsettled levels on day 1 (18 June).
Activity is expected to decrease to quiet levels on day 2 (19 June).
An increase to quiet to unsettled levels is expected on day 3 (20
June) as a coronal hole high-speed stream begins to disturb the
field.
III. Event Probabilities 18 Jun-20 Jun
Class M 20/20/20
Class X 01/01/01
Proton 01/01/01
PCAF green
IV. Penticton 10.7 cm Flux
Observed 17 Jun 104
Predicted 18 Jun-20 Jun 105/105/105
90 Day Mean 17 Jun 104
V. Geomagnetic A Indices
Observed Afr/Ap 16 Jun 003/004
Estimated Afr/Ap 17 Jun 013/013
Predicted Afr/Ap 18 Jun-20 Jun 007/008-005/005-008/008
VI. Geomagnetic Activity Probabilities 18 Jun-20 Jun
A. Middle Latitudes
Active 15/10/20
Minor storm 01/01/05
Major-severe storm 01/01/01
B. High Latitudes
Active 20/15/25
Minor storm 01/01/10
Major-severe storm 01/01/01