Product: Weekly Highlights and Forecasts
:Issued: 2026 Aug 03 0413 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
# Product description and SWPC contact on the Web
# https://www.swpc.noaa.gov/content/subscription-services
#
# Weekly Highlights and Forecasts
#
Highlights of Solar and Geomagnetic Activity
27 July - 02 August 2026
Solar activity reached Moderate levels during the period, with a
total of 35 C-class flares and 2 R1 (Minor) radio blackout events.
Region 4494 (S05, L=88) produced an M1.0/Sf peaking at 27/0243 UTC
and Region 4492 (N=15, L=107, class/area Cko/310 on 26 July)
produced the largest flare of the week, a long-duration M1.9/Sf that
peaked at 30/1700 UTC. This event was accompanied by a partial-halo
CME and a simultaneous eight-degree-long filament eruption, centered
near N20W67. Associated with these 30 Jul events, two Type II radio
sweeps were observed at 30/1627 UTC and 30/1645 UTC, with estimated
shock speeds of 843 km/s and 1,681 km/s, respectively. Other radio
events included a Type IV sweep at 30/1631 UTC and a 17-minute-long
Tenflare (190 sfu) that peaked at 30/1643 UTC.
Analysis of the CME propagation indicated an Earth-directed
component with estimated velocity of 878 km/s that was anticipated
to disturb the Geospace on Aug 02, which was later confirmed by a
Sudden Impulse observed on 02/1229 UTC (with deviation of 27 nT) and
further geomagnetic activity enhancement.
The greater than 10 MeV proton flux crossed the S1 (Minor) solar
radiation event threshold twice during the period: first at 30/1845
UTC (reaching a peak of 18 pfu at 30/2055 UTC); and, after returning
to levels below S1 around 30/0715 UTC, the flux got elevated again
and crossed the threshold of 10pfu at 31/1335 UTC. Additionally, the
greater than 100 MeV proton flux briefly exceeded 1pfu at 30/1835.
All proton flux enhancements were likely associated with the M1.9/Sf
flare mentioned above.
The greater than 2 MeV electron flux at geosynchronous orbit reached
high levels on 27 Jul and 01 Aug, with the maximum value of the
period (1,379 pfu) observed at 27/1630 UTC.
Geomagnetic activity was at Quiet to G2 (Moderate) levels during the
week. Unsettled levels were observed on 27-28 Jul, followed by quiet
levels on 29 Jul to 01 Aug. On 02 Aug, active levels were observed,
with an isolated synoptic period of G2 (Moderate) storming level due
to the impact of the abovementioned CME that left the Sun on 30 Jul.
Forecast of Solar and Geomagnetic Activity
03 August - 29 August 2026
Solar activity is expected to be predominantly at low levels, with a
chance for R1-R2 (Minor-Moderate) levels throughout the outlook
period.
No proton events (greater than 10 MeV) are expected at
geosynchronous orbit.
The greater than 2 MeV electron flux at geosynchronous orbit is
expected to reach high levels on 12-16 Aug and 22-23 Aug due to
recurrent high speed streams. Normal to moderate electron flux
levels are expected for the remaining days of the outlook period.
Geomagnetic activity is expected to reach G1 (Minor) storming levels
on 03 Aug (as the ongoing CME disturbances persist and wane) and on
19 Aug (due to the anticipated effects of a High Speed Stream
originated in a negative polarity Coronal Hole). Active levels are
expected on 17-18 Aug, due to the -CH HSS previously mentioned.
Unsettled levels are expected on 04, 11-12 and 20 Aug, and Quiet
levels on the remaining days of the outlook period.
:Product: 27-day Space Weather Outlook Table 27DO.txt
:Issued: 2026 Aug 03 0413 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
# Product description and SWPC web contact www.swpc.noaa.gov/content/subscription-services
#
# 27-day Space Weather Outlook Table
# Issued 2026-08-03
#
# UTC Radio Flux Planetary Largest
# Date 10.7 cm A Index Kp Index
2026 Aug 03 125 22 5
2026 Aug 04 120 10 3
2026 Aug 05 115 5 2
2026 Aug 06 110 5 2
2026 Aug 07 110 5 2
2026 Aug 08 105 5 2
2026 Aug 09 105 5 2
2026 Aug 10 105 5 2
2026 Aug 11 105 8 3
2026 Aug 12 105 8 3
2026 Aug 13 110 5 2
2026 Aug 14 115 5 2
2026 Aug 15 115 5 2
2026 Aug 16 115 5 2
2026 Aug 17 120 15 4
2026 Aug 18 120 12 4
2026 Aug 19 125 20 5
2026 Aug 20 125 8 3
2026 Aug 21 130 5 2
2026 Aug 22 135 5 2
2026 Aug 23 135 5 2
2026 Aug 24 130 5 2
2026 Aug 25 130 5 2
2026 Aug 26 125 5 2
2026 Aug 27 120 5 2
2026 Aug 28 115 5 2
2026 Aug 29 110 5 2
(NOAA)
