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Sunspot Number History & HF Propagation

Daily sunspot numbers provide a longer view of solar activity. Compare the last month, quarter or year, then combine the trend with current solar flux and geomagnetic conditions when planning HF operation.

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NOAA observed readings

Daily Sunspot Number

Latest reading: 96 on November 7, 2026.

96 on Nov 7, 2026

063125188250Nov 8, 2025Nov 7, 2026
Daily reading 30-day average
View daily values as a table
DateSunspot number
Nov 7, 202696
Nov 6, 202691
Nov 5, 202689
Nov 4, 202664
Nov 3, 202641
Nov 2, 202637
Nov 1, 202630
Oct 31, 202624
Oct 30, 202636
Oct 29, 202622
Oct 28, 202612
Oct 27, 202625
Oct 26, 202625
Oct 25, 202622
Oct 24, 202625
Oct 23, 202651
Oct 22, 202649
Oct 21, 202666
Oct 20, 202666
Oct 19, 202666
Oct 18, 202682
Oct 17, 202687
Oct 16, 202681
Oct 15, 2026104
Oct 14, 2026124
Oct 13, 2026102
Oct 12, 202693
Oct 11, 202694
Oct 10, 202699
Oct 9, 202693
Oct 8, 202669
Oct 7, 202678
Oct 6, 202677
Oct 5, 202658
Oct 4, 202655
Oct 3, 202653
Oct 2, 202637
Oct 1, 202638
Sep 30, 202629
Sep 29, 202628
Sep 28, 202646
Sep 27, 202667
Sep 26, 202688
Sep 25, 2026110
Sep 24, 2026124
Sep 23, 2026142
Sep 22, 2026126
Sep 21, 202685
Sep 20, 202654
Sep 19, 202611
Sep 18, 20260
Sep 17, 202611
Sep 16, 202623
Sep 15, 202623
Sep 14, 202651
Sep 13, 202677
Sep 12, 202687
Sep 11, 202688
Sep 10, 202690
Sep 9, 2026107
Sep 8, 2026102
Sep 7, 2026103
Sep 6, 202683
Sep 5, 202670
Sep 4, 202672
Sep 3, 202637
Sep 2, 202673
Sep 1, 202655
Aug 31, 202681
Aug 30, 202674
Aug 29, 202673
Aug 28, 202692
Aug 27, 202676
Aug 26, 202699
Aug 25, 202683
Aug 24, 202684
Aug 23, 202673
Aug 22, 202687
Aug 21, 202659
Aug 20, 202672
Aug 19, 202678
Aug 18, 202671
Aug 17, 202676
Aug 16, 202683
Aug 15, 2026111
Aug 14, 2026106
Aug 13, 2026101
Aug 12, 202682
Aug 11, 202662
Aug 10, 202655
Aug 9, 202641
Aug 8, 202662
Aug 7, 202672
Aug 6, 202671
Aug 5, 202686
Aug 4, 2026100
Aug 3, 2026104
Aug 2, 2026105
Aug 1, 2026102
Jul 31, 2026123
Jul 30, 2026130
Jul 29, 2026123
Jul 28, 2026102
Jul 27, 202689
Jul 26, 202699
Jul 25, 202686
Jul 24, 2026101
Jul 23, 202688
Jul 22, 202663
Jul 21, 202688
Jul 20, 202674
Jul 19, 202644
Jul 18, 202624
Jul 17, 202626
Jul 16, 202647
Jul 15, 202625
Jul 14, 202636
Jul 13, 202659
Jul 12, 202670
Jul 11, 202682
Jul 10, 202662
Jul 9, 202677
Jul 8, 202681
Jul 7, 202650
Jul 6, 202685
Jul 5, 2026116
Jul 4, 202697
Jul 3, 2026112
Jul 2, 2026101
Jul 1, 2026146
Jun 30, 2026139
Jun 29, 2026132
Jun 28, 2026131
Jun 27, 2026119
Jun 26, 202699
Jun 25, 2026136
Jun 24, 2026126
Jun 23, 2026106
Jun 22, 202681
Jun 21, 202653
Jun 20, 202673
Jun 19, 202655
Jun 18, 202646
Jun 17, 202650
Jun 16, 202676
Jun 15, 202678
Jun 14, 202661
Jun 13, 202641
Jun 12, 2026113
Jun 11, 202681
Jun 10, 2026114
Jun 9, 2026120
Jun 8, 2026119
Jun 7, 2026124
Jun 6, 2026139
Jun 5, 2026145
Jun 4, 2026157
Jun 3, 2026141
Jun 2, 2026133
Jun 1, 2026146
May 31, 2026110
May 30, 2026133
May 29, 2026135
May 28, 2026161
May 27, 2026165
May 26, 2026148
May 25, 2026132
May 24, 202686
May 23, 202686
May 22, 202667
May 21, 202676
May 20, 202667
May 19, 202672
May 18, 202677
May 17, 202686
May 16, 202683
May 15, 202646
May 14, 202660
May 13, 202656
May 12, 202658
May 11, 202679
May 10, 202689
May 9, 202681
May 8, 202675
May 7, 202659
May 6, 2026105
May 5, 2026119
May 4, 2026143
May 3, 2026138
May 2, 2026133
May 1, 2026158
Apr 30, 2026130
Apr 29, 2026142
Apr 28, 2026144
Apr 27, 2026122
Apr 26, 2026137
Apr 25, 2026154
Apr 24, 2026123
Apr 23, 202671
Apr 22, 202672
Apr 21, 202668
Apr 20, 202646
Apr 19, 202635
Apr 18, 202644
Apr 17, 202650
Apr 16, 202665
Apr 15, 202657
Apr 14, 202664
Apr 13, 202658
Apr 12, 202647
Apr 11, 202642
Apr 10, 202648
Apr 9, 202679
Apr 8, 2026103
Apr 7, 2026110
Apr 6, 2026112
Apr 5, 2026112
Apr 4, 2026113
Apr 3, 2026118
Apr 2, 2026152
Apr 1, 2026130
Mar 31, 2026133
Mar 30, 2026143
Mar 29, 2026125
Mar 28, 2026116
Mar 27, 2026152
Mar 26, 2026113
Mar 25, 2026103
Mar 24, 2026113
Mar 23, 202694
Mar 22, 202696
Mar 21, 202648
Mar 20, 202628
Mar 19, 202638
Mar 18, 202683
Mar 17, 202672
Mar 16, 202666
Mar 15, 202693
Mar 14, 202685
Mar 13, 2026105
Mar 12, 2026116
Mar 11, 2026120
Mar 10, 202671
Mar 9, 202672
Mar 8, 202676
Mar 7, 202675
Mar 6, 202675
Mar 5, 202673
Mar 4, 202671
Mar 3, 202664
Mar 2, 202682
Mar 1, 202685
Feb 28, 202644
Feb 27, 202653
Feb 26, 202643
Feb 25, 202625
Feb 24, 20260
Feb 23, 20260
Feb 22, 20260
Feb 21, 202611
Feb 20, 202634
Feb 19, 202639
Feb 18, 202643
Feb 17, 202663
Feb 16, 202669
Feb 15, 202665
Feb 14, 202660
Feb 13, 202650
Feb 12, 202682
Feb 11, 202684
Feb 10, 2026105
Feb 9, 2026107
Feb 8, 2026118
Feb 7, 2026128
Feb 6, 2026132
Feb 5, 2026139
Feb 4, 2026166
Feb 3, 2026171
Feb 2, 2026131
Feb 1, 202697
Jan 31, 2026126
Jan 30, 2026112
Jan 29, 2026117
Jan 28, 2026135
Jan 27, 2026100
Jan 26, 2026115
Jan 25, 2026131
Jan 24, 2026147
Jan 23, 2026195
Jan 22, 2026206
Jan 21, 2026166
Jan 20, 2026172
Jan 19, 2026162
Jan 18, 2026140
Jan 17, 2026124
Jan 16, 2026144
Jan 15, 2026123
Jan 14, 202670
Jan 13, 202649
Jan 12, 202652
Jan 11, 202684
Jan 10, 202665
Jan 9, 202680
Jan 8, 202696
Jan 7, 2026118
Jan 6, 202699
Jan 5, 202691
Jan 4, 202697
Jan 3, 2026136
Jan 2, 2026124
Jan 1, 2026120
Dec 31, 2025127
Dec 30, 2025141
Dec 29, 2025138
Dec 28, 2025143
Dec 27, 2025130
Dec 26, 2025131
Dec 25, 2025113
Dec 24, 2025103
Dec 23, 2025106
Dec 22, 202580
Dec 21, 202585
Dec 20, 202574
Dec 19, 202533
Dec 18, 202587
Dec 17, 202568
Dec 16, 202581
Dec 15, 202573
Dec 14, 202578
Dec 13, 202576
Dec 12, 2025124
Dec 11, 2025123
Dec 10, 2025134
Dec 9, 2025134
Dec 8, 2025146
Dec 7, 2025133
Dec 6, 2025129
Dec 5, 2025133
Dec 4, 2025165
Dec 3, 2025227
Dec 2, 2025177
Dec 1, 2025175
Nov 30, 2025108
Nov 29, 202574
Nov 28, 202587
Nov 27, 202576
Nov 26, 202585
Nov 25, 202599
Nov 24, 202599
Nov 23, 202579
Nov 22, 202574
Nov 21, 202575
Nov 20, 202551
Nov 19, 202560
Nov 18, 202566
Nov 17, 202545
Nov 16, 202566
Nov 15, 202597
Nov 14, 2025114
Nov 13, 2025104
Nov 12, 2025150
Nov 11, 2025131
Nov 10, 2025128
Nov 9, 2025126
Nov 8, 2025107

Daily readings: NOAA Space Weather Prediction Center. A missing date is left blank, not treated as zero. The optional average is calculated from 30 consecutive daily readings.

What does this number mean?

The sunspot number is an activity index based on the number of sunspot groups and individual spots visible on the Sun. It is not simply a count of spots. NOAA publishes the daily observed value shown here.

Why does it matter for HF?

Over weeks and months, higher sunspot activity is often associated with stronger ionization high in Earth's atmosphere. That can help higher HF bands, especially 15, 12, and 10 meters, support longer-distance contacts.

How should I use the graph?

Look for the direction of the trend, not a promise about a particular day or path. Today's openings also depend on solar flux, geomagnetic conditions, flares, daylight, season, and the stations at both ends of a contact.

Learn more from NOAA's solar cycle explanation and ARRL's HF propagation guide.

Build a clearer picture

Explore solar & geomagnetic conditions

Each measurement tells part of the story. Compare solar activity with geomagnetic conditions, daylight and your operating path.

Live HF Propagation & Space Weather

Check current HF radio conditions with NOAA solar flux, Kp, solar wind, Bz, X-ray and sunspot data, history charts, band guidance and a live greyline map.

Explore current conditions →

Solar Flux Index (SFI) & F10.7 History

Track NOAA's Solar Flux Index with 7, 14 and 30-day F10.7 charts, daily readings and a 7-day average. Learn what solar flux means for HF propagation.

Explore the readings →

Planetary Kp Index & Geomagnetic Activity

Explore NOAA planetary Kp index history over 1, 3 or 7 days. Compare three-hour geomagnetic readings and learn how disturbed conditions can affect HF radio.

Explore the readings →

Solar Wind Speed & HF Radio Conditions

Follow NOAA solar wind speed in km/s with 6, 12 and 24-hour history charts. Learn why sustained speed changes, IMF Bz and Kp matter together for HF radio.

Explore the readings →

IMF Bz & the Solar Wind Magnetic Field

View NOAA IMF Bz history over 6, 12 or 24 hours. Understand positive and negative nanotesla readings and why sustained southward Bz matters for geomagnetic activity.

Explore the readings →

GOES X-Ray Flux & Solar Flare History

Explore NOAA GOES X-ray flux and solar flare history over 1, 3 or 7 days. Understand A, B, C, M and X classes and their relevance to sunlit-side HF radio blackouts.

Explore the readings →