:Product: Weekly Highlights and Forecasts
:Issued: 2017 Sep 18 0327 UTC
#
Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
#
Product description and SWPC contact on the Web
# http://www.swpc.noaa.gov/weekly.html
#
#
Weekly Highlights and Forecasts
#
Highlights of Solar and Geomagnetic
Activity 11 - 17 September 2017
Solar activity was at predominately very
low levels through the
summary period, interupted by a brief period of low
activity on 12
Sep as Region 2680 (N09, L=317, class/area Hsx/140 on 12
Sep)
produced a pair of impulsive C-class flares. 11 Sep saw the
X-ray
background elevated at the C-level due to slow decay from the
X8
flare (R3-Strong) observed at 10/1606 UTC. No Earth-directed CMEs
were
detected during the period.
Of note, two halo CMEs were observed on 17
Sep. The first one, a
full-halo CME, was first observed in LASCO C2 imagery
at 17/1224
UTC, while the second one was a partial-halo CME, first observed
in
LASCO C2 imagery at 17/1424 UTC. The source region of both CMEs
was
determined to be from old active Region 2673 (S09, L=119) which
is
presently on the back side of the solar disk. Old Region 2673 is due
to
return on 23 Sep.
10 MeV and 100 MeV protons at geosynchronous orbit
exceeded their
respective event thresholds during the period, both in
response to
the X8 flare observed on 10 Sep. At 10/1645 UTC, 10 MeV
protons
exceeded 10 pfu (S1-Minor), reached a maximum of 1,490
pfu
(S3-Strong) and decayed below the S1 level at 14/1725 UTC. The 100
MeV
proton flux exceeded the 1 pfu level at 10/1625 UTC, reached a
maximum of 68
pfu at 10/2215 UTC and ended at 13/0335 UTC.
The greater than 2 MeV
electron flux at geosynchronous orbit was at
moderate levels on 13-14 Sep and
high levels on 11-12 and 15-17 Sep.
A maximum of 46,263 pfu was observed at
17/1610 UTC.
Geomagnetic field activity was a quiet to minor storm
levels
(G1-Minor) and major storm levels (G2-Moderate) during the
summary
period. Quiet to unsettled levels were observed on 11 Sep
through
late on 12 Sep due to waning effects from a negative polarity
CH
HSS. Late on 12 Sep through midday on 13 Sep, field activity
increased
to active to minor storm levels (G1-Minor) in response to
CME effects from
the 10 Sep X8 flare. During this timeframe, total
field peaked at 16 nT, the
Bz component reached a maximum southward
extent of -12 nT and solar wind
speed peaked at about 650 km/s.
Quiet levels were observed for the remainder
of 13 Sep through
midday on 14 Sep.
From midday on 14 Sep through 17
Sep, field activity was dominated
by effects from a recurrent, positive
polarity CH HSS. Unsettled to
G1-Minor and G2-Moderate levels were observed
through 16 Sep with
quiet to active levels present on 17 Sep. During this
timeframe,
total field peaked at near 22 nT, the Bz component reached a
maximum
southward extent of -18 nT and solar wind speed peaked at about
775
km/s.
FORECAST OF SOLAR AND GEOMAGNETIC ACTIVITY 18 SEPT-14 OCT
2017
Solar activity is expected to be at predominately very low levels
on
18-22 Sep and 08-14 Oct. R1-R2 (Minor-Moderate) levels are expected
on
23 Sep-07 Oct due to the return of old Region 2673 (S09, L=119).
The
greater than 10 MeV protons at geosynchronous orbit are expected
to remain at
background levels from 18-22 Sep and 08-14 Oct. A
chance for an S1-S2
(Minor-Moderate) proton event is possible from
23 Sep-07 Oct in association
with significant flare activity after
the return of old Region 2673.
The greater than 2 MeV electron flux at geosynchronous orbit
is
expected to be at high levels on 18-22 Sep, 28 Sep-19 Oct and 12-14
Oct
due to CH HSS influence. Normal to moderate levels are expected
for the
remainder of the outlook period.
Geomagnetic field activity is expected
to be at unsettled to active
levels on 18-20 Sep, 24-25 Sep and 30 Sep-02 Oct
with G1 (Minor)
storm conditions possible on 27-29 Sep and 11-14 Oct due
to
recurrent CH HSS activity. Mostly quiet conditions are expected for
the
remainder of the outlook period.
:Product: 27-day Space Weather Outlook
Table 27DO.txt
:Issued: 2017 Sep 18 0327 UTC
# Prepared by the US Dept. of
Commerce, NOAA, Space Weather Prediction Center
# Product description and
SWPC contact on the Web
# http://www.swpc.noaa.gov/wwire.html
#
#
27-day Space Weather Outlook Table
# Issued
2017-09-18
#
# UTC Radio Flux Planetary Largest
#
Date 10.7 cm A Index Kp Index
2017 Sep 18 75
15 4
2017 Sep 19 75 12 4
2017 Sep 20
75 10 3
2017 Sep 21 75 5 2
2017
Sep 22 75 5 2
2017 Sep 23 95
8 3
2017 Sep 24 110 18 5
2017 Sep 25
110 12 4
2017 Sep 26 110 8 3
2017
Sep 27 110 20 5
2017 Sep 28 110
20 5
2017 Sep 29 115 20 5
2017 Sep 30
115 18 4
2017 Oct 01 115 15 4
2017
Oct 02 115 12 4
2017 Oct 03 115
8 3
2017 Oct 04 115 5 2
2017 Oct 05
115 5 2
2017 Oct 06 115 5 2
2017
Oct 07 110 5 2
2017 Oct 08 85
5 2
2017 Oct 09 76 5 2
2017 Oct 10
75 5 2
2017 Oct 11 74 25 5
2017
Oct 12 73 25 5
2017 Oct 13 72
25 5
2017 Oct 14 72 20 5
(SWPC via
DXLD)
