Space weather, week 45 of 2026.
·Week 45 of 2026, November 2, 2026 to November 8, 2026, 7 of 7 days recorded. Earth's magnetic field reached storm level on 2 days; the most disturbed day was November 7, 2026, with the Kp index (0 to 9, storm at 5 and above) peaking at 5.3, minor geomagnetic storm (G1). The Sun let off 7 medium (M-class) and 82 small (C-class) flares over the week. The daily sunspot count ran from 37 to 93, averaging 70, a moderately active Sun.
One section per complete UTC day, written by the daily data run from NOAA's feeds: the planetary Kp index every three hours, the GOES X-ray flare list, NOAA's daily sunspot number and 10.7 cm flux, and hourly solar wind at L1. Nothing here is edited by hand. The record index explains each figure, and the same numbers are in the open data file.
Monday, November 2, 2026
Earth's magnetic field was unsettled: the Kp index, a 0 to 9 scale where 5 and above counts as a geomagnetic storm, peaked at 3 in the 06:00 to 09:00 UTC window and averaged 1.6 for the day. Aurora stayed up near the poles. The Sun produced no flares worth recording (nothing reached C class, the smallest size NOAA lists). NOAA's sunspot count was 37, a quiet Sun for this stage of the cycle (0 is no spots at all; 150 to 200 is typical at the peak of a cycle); 1 new sunspot group appeared. The Sun's radio output, a second gauge of its activity that does not depend on counting spots, read 97, moderate (about 70 for a quiet Sun, 200 or more for a very active one). The solar wind, the stream of particles flowing past Earth, averaged 424 km per second, a normal pace, and peaked at 589. Its magnetic field stayed mostly northward (Bz no lower than -4.5 nT), the direction that keeps storms away.
Kp through the day, one value per three hours from midnight UTC: 1, 2, 3, 2.3, 1.7, 1.7, 1, 0.3.
Tuesday, November 3, 2026
Earth's magnetic field was quiet: the Kp index, a 0 to 9 scale where 5 and above counts as a geomagnetic storm, peaked at 2 in the 06:00 to 09:00 UTC window and averaged 1.4 for the day. Aurora stayed up near the poles. The Sun let off 1 small (C-class) flare; the biggest was C1.1 at 22:39 UTC, too small to notice on Earth. NOAA's sunspot count was 41, a quiet Sun for this stage of the cycle (0 is no spots at all; 150 to 200 is typical at the peak of a cycle); no new sunspot groups appeared. The Sun's radio output, a second gauge of its activity that does not depend on counting spots, read 100, moderate (about 70 for a quiet Sun, 200 or more for a very active one). The solar wind, the stream of particles flowing past Earth, averaged 369 km per second, a normal pace, and peaked at 431. Its magnetic field stayed mostly northward (Bz no lower than -4.4 nT), the direction that keeps storms away (23 of 24 hours recorded).
Kp through the day, one value per three hours from midnight UTC: 0.7, 1.7, 2, 1.7, 0.7, 1.3, 1.7, 1.3.
Wednesday, November 4, 2026
Earth's magnetic field was unsettled: the Kp index, a 0 to 9 scale where 5 and above counts as a geomagnetic storm, peaked at 3.3 in the 06:00 to 09:00 UTC window and averaged 2.2 for the day. Aurora stayed up near the poles. The Sun let off 2 small (C-class) flares; the biggest was C2.2 at 17:34 UTC, too small to notice on Earth. NOAA's sunspot count was 64, a quiet Sun for this stage of the cycle (0 is no spots at all; 150 to 200 is typical at the peak of a cycle); 1 new sunspot group appeared. The Sun's radio output, a second gauge of its activity that does not depend on counting spots, read 111, moderate (about 70 for a quiet Sun, 200 or more for a very active one). The solar wind, the stream of particles flowing past Earth, averaged 391 km per second, a normal pace, and peaked at 703. Its magnetic field tipped southward for a time (Bz down to -7.7 nT), the direction that feeds storms (23 of 24 hours recorded).
Kp through the day, one value per three hours from midnight UTC: 2.3, 2.7, 3.3, 2.3, 3, 1, 1.7, 1.3.
Thursday, November 5, 2026
Earth's magnetic field was quiet: the Kp index, a 0 to 9 scale where 5 and above counts as a geomagnetic storm, peaked at 2.3 in the 21:00 to 24:00 UTC window and averaged 1.5 for the day. Aurora stayed up near the poles. The Sun let off 1 medium (M-class) and 4 small (C-class) flares; the biggest was M3.5 at 18:33 UTC, enough for a brief shortwave radio fade on the daylit side. NOAA's sunspot count was 89, a moderately active Sun (0 is no spots at all; 150 to 200 is typical at the peak of a cycle); 1 new sunspot group appeared. The Sun's radio output, a second gauge of its activity that does not depend on counting spots, read 124, moderate (about 70 for a quiet Sun, 200 or more for a very active one). The solar wind, the stream of particles flowing past Earth, averaged 344 km per second, a slow day, and peaked at 420. Its magnetic field tipped southward for a time (Bz down to -5.6 nT), the direction that feeds storms.
Kp through the day, one value per three hours from midnight UTC: 1.3, 1.7, 1.7, 1.3, 0.7, 0.7, 2, 2.3.
Friday, November 6, 2026
Earth's magnetic field was unsettled: the Kp index, a 0 to 9 scale where 5 and above counts as a geomagnetic storm, peaked at 3.3 in the 21:00 to 24:00 UTC window and averaged 2.2 for the day. Aurora stayed up near the poles. The Sun let off 22 small (C-class) flares; the biggest was C5.6 at 02:51 UTC, too small to notice on Earth. NOAA's sunspot count was 91, a moderately active Sun (0 is no spots at all; 150 to 200 is typical at the peak of a cycle); 2 new sunspot groups appeared. The Sun's radio output, a second gauge of its activity that does not depend on counting spots, read 125, moderate (about 70 for a quiet Sun, 200 or more for a very active one). The solar wind, the stream of particles flowing past Earth, averaged 355 km per second, a normal pace, and peaked at 440. Its magnetic field tipped southward for a time (Bz down to -9.7 nT), the direction that feeds storms.
Kp through the day, one value per three hours from midnight UTC: 2.3, 0.7, 2.7, 2.3, 2, 2, 2.3, 3.3.
Saturday, November 7, 2026
Earth's magnetic field was in a minor geomagnetic storm (G1): the Kp index, a 0 to 9 scale where 5 and above counts as a geomagnetic storm, peaked at 5.3 in the 18:00 to 21:00 UTC window and averaged 3.4 for the day. Aurora could reach the northern US states, Scotland, and Scandinavia. The Sun let off 3 medium (M-class) and 26 small (C-class) flares; the biggest was M1.9 at 18:42 UTC, enough for a brief shortwave radio fade on the daylit side. NOAA's sunspot count was 93, a moderately active Sun (0 is no spots at all; 150 to 200 is typical at the peak of a cycle); no new sunspot groups appeared. The Sun's radio output, a second gauge of its activity that does not depend on counting spots, read 127, moderate (about 70 for a quiet Sun, 200 or more for a very active one). The solar wind, the stream of particles flowing past Earth, averaged 535 km per second, fast, and peaked at 1156. Its magnetic field swung strongly southward for a time (Bz down to -10.9 nT), the direction that lets energy into Earth's field and drives storms.
Kp through the day, one value per three hours from midnight UTC: 3, 2.3, 3.3, 3.3, 3, 3, 5.3, 4.
Sunday, November 8, 2026
Earth's magnetic field was in a minor geomagnetic storm (G1): the Kp index, a 0 to 9 scale where 5 and above counts as a geomagnetic storm, peaked at 5 in the 00:00 to 03:00 UTC window and averaged 3.4 for the day. Aurora could reach the northern US states, Scotland, and Scandinavia. The Sun let off 3 medium (M-class) and 27 small (C-class) flares; the biggest was M1.7 at 07:46 UTC, enough for a brief shortwave radio fade on the daylit side. NOAA's sunspot count was 72, a moderately active Sun (0 is no spots at all; 150 to 200 is typical at the peak of a cycle); 1 new sunspot group appeared. The Sun's radio output, a second gauge of its activity that does not depend on counting spots, read 128, moderate (about 70 for a quiet Sun, 200 or more for a very active one). The solar wind, the stream of particles flowing past Earth, averaged 731 km per second, very fast, the kind of stream that stirs up storms, and peaked at 832. Its magnetic field tipped southward for a time (Bz down to -8.7 nT), the direction that feeds storms (22 of 24 hours recorded).
Kp through the day, one value per three hours from midnight UTC: 5, 3.3, 3, 3.3, 2.7, 3.3, 4, 2.7.
What do these numbers mean?
Four things are tracked each day. The Kp index says how disturbed Earth's magnetic field was, on a 0 to 9 scale measured every three hours; 5 and above is a geomagnetic storm, and the higher it goes the farther south the aurora reaches. Flares are sudden flashes on the Sun, sorted by size: C-class is small and harmless, M-class is medium and can briefly fade shortwave radio, X-class is large. The sunspot count is NOAA's daily tally of dark spots, weighted so that groups count more than lone spots; it runs from 0 on a blank Sun to 150 or more near the peak of a solar cycle. The radio output is the Sun's brightness at a 10.7 cm radio wavelength, a second activity gauge that does not depend on counting spots; 70 is quiet, 200 very active. The solar wind is the stream of particles flowing past Earth, measured about 1.5 million km upstream; its speed and the north-south direction of its magnetic field (Bz) decide whether a storm follows, because a southward field lets the wind's energy into Earth's field.