Viewing archive of Tuesday, 5 September 2017
Solar activity report
Any mentioned solar flare in this report has a scaling factor applied by the Space Weather Prediction Center (SWPC). Because of the SWPC scaling factor, solar flares are reported as 42% smaller than for the science quality data. The scaling factor has been removed from our archived solar flare data to reflect the true physical units.
Report of Solar-Geophysical Activity 2017 Sep 05 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 248 Issued at 2200Z on 05 Sep 2017IA. Analysis of Solar Active Regions and Activity from 04-2100Z to 05-2100Z Solar activity has been at high levels for the past 24 hours.
The largest solar event of the period was a M4 event observed at
05/0108Z. There are currently 6 numbered sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is expected to be moderate
with a chance for X-class flares on days one, two, and three (06 Sep, 07
Sep, 08 Sep).
IIA. Geophysical Activity Summary 04-2100Z to 05-2100Z
The geomagnetic
field has been at quiet to minor storm levels for the past 24 hours.
Solar wind speed reached a peak of 629 km/s at 05/0140Z. Total IMF
reached 8 nT at 04/2145Z. The maximum southward component of Bz reached
-6 nT at 04/2207Z. Protons greater than 10 MeV at geosynchronous orbit
reached a peak level of 210 pfu at 05/1930Z. Electrons greater than 2
MeV at geosynchronous orbit reached a peak level of 3776 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at unsettled to severe storm levels on day one (06 Sep), active to
severe storm levels on day two (07 Sep) and unsettled to active levels
on day three (08 Sep). Protons are expected to cross threshold on day
one (06 Sep), are likely to cross threshold on day two (07 Sep) and have
a slight chance of crossing threshold on day three (08 Sep).
III. Event Probabilities 06 Sep to 08 Sep
| Class M | 75% | 75% | 75% |
| Class X | 25% | 25% | 25% |
| Proton | 99% | 70% | 15% |
| PCAF | red | ||
IV. Penticton 10.7 cm Flux
Observed 05 Sep 121 Predicted 06 Sep-08 Sep 120/115/115 90 Day Mean 05 Sep 079
V. Geomagnetic A Indices
Observed Afr/Ap 04 Sep 016/017 Estimated Afr/Ap 05 Sep 010/012 Predicted Afr/Ap 06 Sep-08 Sep 022/040-026/048-020/022
VI. Geomagnetic Activity Probabilities 06 Sep to 08 Sep
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 35% |
| Minor storm | 40% | 35% | 15% |
| Major-severe storm | 45% | 50% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 01% | 15% | 15% |
| Minor storm | 10% | 35% | 20% |
| Major-severe storm | 90% | 45% | 20% |
All times in UTC
Latest news
Sunday, 1 February 2026
Complex sunspot region 4366
Monday, 19 January 2026
CME impact! S4 solar radiation storm
Sunday, 18 January 2026
X1.9 solar flare with earth-directed CME
Latest forum messages
Comet C/2026 A1 (MAPS) for the southern hemisphere 12Available resources & tools / space weather databases 11JHelioviewer Tips and Settings 45AR4387 / AR4389 7Unspecified geomagnetic activity 93
More topicsSupport SpaceWeatherLive.com!
A lot of people come to SpaceWeatherLive to follow the Solar activity or if there is a chance to see the aurora, but with more traffic comes higher costs to keep the servers online. If you like SpaceWeatherLive and want to support the project you can choose a subscription for an ad-free site or consider a donation. With your help we can keep SpaceWeatherLive online!
Space weather facts
| Last X-flare | 2026/02/04 | X4.21 |
| Last M-flare | 2026/02/25 | M2.4 |
| Last geomagnetic storm | 2026/03/03 | Kp5 (G1) |
| Spotless days | |
|---|---|
| Last 365 days | 3 days |
| 2026 | 3 days (4%) |
| Last spotless day | 2026/02/24 |
| Monthly mean Sunspot Number | |
|---|---|
| February 2026 | 78.2 -34.3 |
| March 2026 | 74.4 -3.8 |
| Last 30 days | 52.8 -75.1 |