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Monday, July 17, 2017

Weely Propagation Forecast Bulletins


Product: Weekly Highlights and Forecasts
:Issued: 2017 Jul 17 0154 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
# Product description and SWPC web contact www.swpc.noaa.gov/weekly.html
#
#                Weekly Highlights and Forecasts
#
Highlights of Solar and Geomagnetic Activity 10 - 16 July 2017

Solar activity was at very low levels on 12 Jul, low levels on 10,  11, 13, 15 and 16 Jul and moderate (R1-Minor) levels on 14 Jul. Region 2665 (S06, L=111, class/area Ekc/710 on 09 Jul) produced a
majority of the flare activity. However, new Region 2667 (N12, L=155, class/area Axx/010 on 14 Jul) produced all of the C-class activity on 13 Jul including a C8 x-ray event with a Type II radio
emission (770 km/s). The largest event of the summary period was a long-duration M2/1n flare from Region 2665 observed at 14/0209 UTC.
Associated with this event was a Tenflare (130 sfu) and Type IV radio emission. At 14/0125 UTC, LASCO C2 imagery detected an asymmetric halo CME that was analyzed and modelled to reveal an
Earth-directed component with a likely arrival at Earth on 16 Jul.

A greater than 10 MeV at greater than or equal to 10 pfu proton event (S1-Minor) began at 14/0900 UTC, reached a maximum flux of 22 pfu at 14/2320 UTC and ended at 15/1115 UTC.

The greater than 2 MeV electron flux at geosynchronous orbit was at moderate flux levels then entire summary period. A maximum flux of 942 pfu was observed at 14/1750 UTC.

Geomagnetic field activity was at quiet to unsettled levels, with isolated active intervals, on 10-11 Jul due to waning effects from a positive polarity CH HSS. Solar wind speeds reached a peak of about
650 km/s early on 11 Jul and steadily decreased through the summary period to reach a low speed of 287 km/s at 16/0446 UTC. Quiet levels were recorded from mid-day 11 Jul through early on 16 Jul.

At 16/0515 UTC, an interplanetary shock associated with the arrival of the 14 Jul CME, was observed in DSCOVR solar wind data. Solar wind speeds sharply increased from around 320 km/s to 502 km/s. Solar wind speeds then slowly increased to a peak value of 643 km/s observed at 16/2037 UTC. Total field strength values reached 28 nT at 16/0836 UTC while the Bz component was sustained at around -23 nT for a prolonged period following the shock arrival. Solar wind density reached a peak of around 56 particles/cubic cm following the shock and the phi angle became highly variable after 16/0515 UTC. Phi angle settled into a mostly positive (away) solar sector after
16/1100 UTC. The geomagnetic field was quiet until 16/0601 UTC when  a geomagnetic sudden impulse was observed (40 nT at Hartland magnetometer) indicating the arrival of the 14 Jul CME. The geomagnetic field responded with active to G1 and G2 (Minor to Moderate) geomagnetic storm levels through the remainder of 16 Jul.

Forecast of Solar and Geomagnetic Activity 17 July - 12 August 2017
Solar activity is expected to be low with a chance for M-class flare activity (R1-R2 / Minor-Moderate) through 19 Jul when Region 2665 exits the visible disk. Very low to low levels are expected from 20-28 Jul. A chance for R1-R2 activity is possible with the return of old Region 2665 from 29 Jul - 12 Aug.

There is a chance for an S1 (Minor) solar radiation storm through 19 Jul due to potential significant flare activity from Region 2665. No proton events are expected from 20-28 Jul. A chance for S1 (Minor) solar radiation storms is possible with the return of old Region 2665 from 29 Jul - 12 Aug.

The greater than 2 MeV electron flux at geosynchronous orbit is expected to be reach high levels on 19-20 Jul due to influence from the 14 Jul CME. Normal to moderate levels are expected for the
remainder of the outlook period.

Geomagnetic field activity is expected to be at G1-G2 (Minor-Moderate) geomagnetic storm levels on 17 Jul due to continued CME effects. Unsettled to active levels are expected on 21-22 Jul
and again on 05-06 Aug, with G1 (Minor) geomagnetic storm levels likely on 05 Aug, due to positive polarity CH HSS influence. Quiet to unsettled levels are expected for the remainder of the outlook
period.


Product: 27-day Space Weather Outlook Table 27DO.txt
:Issued: 2017 Jul 17 0154 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
# Product description and SWPC web contact www.swpc.noaa.gov/wwire.html
#
#      27-day Space Weather Outlook Table
#                Issued 2017-07-17
#
#   UTC      Radio Flux   Planetary   Largest
#  Date       10.7 cm      A Index    Kp Index
2017 Jul 17      85          30          6
2017 Jul 18      80          12          4
2017 Jul 19      74           8          3
2017 Jul 20      74           8          3
2017 Jul 21      74          15          4
2017 Jul 22      74          12          4
2017 Jul 23      74           5          2
2017 Jul 24      75           5          2
2017 Jul 25      75           5          2
2017 Jul 26      75           5          2
2017 Jul 27      75           5          2
2017 Jul 28      75           5          2
2017 Jul 29      90           5          2
2017 Jul 30      90           5          2
2017 Jul 31      90           5          2
2017 Aug 01      90           5          2
2017 Aug 02      90           5          2
2017 Aug 03      90           5          2
2017 Aug 04      90           5          2
2017 Aug 05      90          25          5
2017 Aug 06      90          10          3
2017 Aug 07      90           8          3
2017 Aug 08      90           5          2
2017 Aug 09      90           5          2
2017 Aug 10      90           5          2
2017 Aug 11      90           5          2
2017 Aug 12      85           5          2
(NOAA)