The geomagnetic field was quiet to active on March 2. Solar wind speed at SOHO ranged between 377 and 555 km/sec. The high latitude magnetometer at Andenes recorded quiet to minor storm levels. A high speed coronal hole stream arrived late on March 2 and is causing active geomagnetic conditions early on March 3. It is uncertain if this is the early arrival of effects from CH1133 or if there is another source.
Solar flux density measured at 20h UT on 2.8 GHz was 168.8 - increasing 34.3 over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 135.50). The Potsdam WDC planetary A index was 8 (STAR Ap - based on the mean of three hour interval ap indices: 8.1). Three hour interval K indices: 11221134 (planetary), ******** (Boulder), 21222245 (Andenes).
The background x-ray flux was at the class C1 level (GOES 16).
At the time of counting spots (see image time), spots were observed in 15 active regions using 2K resolution (SN: 233) and in 13 active regions using 1K resolution (SN: 169) SDO/HMI images.
Region 13234 [N23W67] decayed slowly losing
area in the trailing and intermediate spot sections. A major flare is possible as there are still multiple magnetic
deltas.
Region 13236 [S24W71] decayed slowly and was
mostly quiet.
Region 13237 [S12W56] reemerged with tiny spots.
Region 13238 [N09E25] was quiet and stable.
Region 13239 [N32E43] was quiet and stable.
Region 13240 [S14E42] decayed slowly and quietly.
Region 13241 [N28E57] was quiet and stable.
New region 13242 [N10E66] rotated partly into view on March 1 and was
numbered the next day by SWPC as the region developed slowly.
Spotted regions not observed (or interpreted
differently) by SWPC:
S8308 [S21W43] was quiet and stable.
S8311 [S21W04] was quiet and stable.
S8315 [S07W53] was quiet and stable.
S8324 [N18W22] developed slowly and quietly.
New region S8326 [S20E24] was observed with tiny spots in an
old plage area.
New region S8327 [S09E33] emerged with tiny
spots.
New region S8328 [S23E84] rotated partly into view with a large
leader spot.
C2+ flares:
| Magnitude | Peak time (UT) | Location | Source | Recorded by | Comment |
| C4.1 | 03:54 | N08E79 | 13242 | GOES16 | |
| C2.2 | 04:35 | 13242 | GOES16 | ||
| C9.2 | 04:50 | 13234 | GOES16 | ||
| C3.0 | 05:40 | 13241 | GOES16 | ||
| C2.0 | 06:40 | 13234 | GOES16 | ||
| C2.8 | 08:02 | N20W55 | 13234 | GOES16 | simultaneous flare in AR 13242 |
| C2.2 | 08:31 | 13234 | GOES16 | ||
| C2.2 | 09:37 | 13236 | GOES16 | ||
| C2.5 | 10:10 | 13234 | GOES16 | ||
| C3.1 | 10:29 | N20W57 | 13234 | GOES16 | |
| C3.2 | 10:41 | SE limb | S8328 | GOES16 | |
| C3.7 | 11:46 | N09E84 | 13242 | GOES16 | |
| C6.5 | 12:10 | SE limb | S8328 | GOES16 | |
| C2.6 | 12:48 | 13234 | GOES16 | ||
| C2.2 | 14:31 | 13242 | GOES16 | ||
| C2.8 | 15:47 | 13234 | GOES16 | ||
| C3.1 | 16:23 | 13234 | GOES16 | ||
| C2.5 | 19:58 | 13234 | GOES16 | ||
| M3.8/1N | 21:16 | N20W65 | 13234 | GOES16 | Likely CME |
February 28 - March 1: No obviously Earth directed CMEs were observed.
March 2: The M3.8 flare in AR 13234 affected a fairly wide area with
coronal dimming observed. Awaiting LASCO imagery covering the hours after
the event to determine if the likely CME had any Earth directed component.
[Coronal hole history (since October 2002)]
[Compare today's report to the situation one solar rotation ago:
28 days ago
27 days ago
26 days ago]
A trans equatorial coronal hole (CH1133) rotated across the central meridian on March 1-3.
Long distance low and medium frequency (below 2 MHz) propagation along paths north of due west over upper middle and high latitudes is poor. Propagation on long distance northeast-southwest paths is poor.
Quiet to active conditions are likely on March 3-6 due to effects from CH1133, isolated minor storm intervals are possible.
| Coronal holes (1) | Coronal mass ejection (2) | M and X class flares (3) |
1) Effects from a coronal hole
could reach Earth within the next 5 days. When the high speed
stream has arrived the color changes to green.
2) Effects from a CME are likely to be observed at Earth within 96 hours.
3) There is a possibility of either M or X class flares within the next 48 hours.
Green: 0-30% probability, Yellow: 30-70% probability, Red: 70-100% probability.
(Click on image for 2K resolution).
4K resolution.
Compare to the previous day's image. 0.5K image
When available the active region map has a coronal hole polarity overlay where red (pink) is negative and blue is positive.
Data for all officially numbered solar regions according to the Solar Region Summary provided by NOAA/SWPC, all other regions are numbered sequentially as they emerge using the STAR spot number. Comments are my own, as is the STAR spot count (spots observed at or inside a few hours before midnight) and data for regions not numbered by SWPC or where SWPC has observed no spots. SWPC active region numbers in the table below and in the active region map above are the historic SWPC/USAF numbers. SWPC data considered to be not sufficiently precise (location, area, classification) are colored red.
| Active region | SWPC date numbered STAR detected |
Spot count | Location at midnight | Area | Classification | SDO / HMI 4K continuum image with magnetic polarity overlays |
Comment | ||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| SWPC/ USAF |
Magnetic (SDO) |
SWPC | STAR | Current | Previous | ||||||
| 2K | 1K | ||||||||||
| 13230 | 2023.02.17 2023.02.18 |
S23W86 |
 |
location: S22W82 | |||||||
| 13234 | 2023.02.20 2023.02.20 |
20 | 20 | 12 | N25W63 | 0830 | EKC | EKC |
 |
 |
beta-gamma-delta location: N23W67 area: 0640 |
| 13235 | 2023.02.22 2023.02.23 |
N19W87 | |||||||||
| 13236 | 2023.02.23 2023.02.23 |
2 | 5 | 3 | S26W72 | 0010 | BXO | CRO |
 |
 |
location: S24W71 |
| 13237 | 2023.02.23 2023.02.24 |
4 | 3 | S08W52 | 0010 | BXO |
 |
real location: S12W56 SWPC observers were confused by the spots of AR S8315 on February 27 and changed the location to that group |
|||
| S8306 | 2023.02.23 | N12W43 | |||||||||
| S8308 | 2023.02.24 | 2 | 1 | S21W43 | 0004 | BXO |
 |
 |
|||
| S8310 | 2023.02.25 | S26W21 | |||||||||
| S8311 | 2023.02.25 | 10 | 3 | S21W04 | 0020 | BXO |
 |
 |
|||
| S8313 | 2023.02.25 | N18W30 | |||||||||
| 13238 | 2023.02.26 2023.02.27 |
1 | 5 | 2 | N09E22 | 0070 | HSX | CSO |
 |
 |
location: N09E25 area: 0090 |
| S8315 | 2023.02.26 | 1 | S07W53 | 0002 | AXX |
 |
 |
||||
| S8316 | 2023.02.27 | N18W31 | |||||||||
| 13239 | 2023.02.27 2023.02.28 |
1 | 2 | 1 | N31E41 | 0100 | HSX | HSX |
 |
 |
location: N32E43 area: 0200 |
| S8318 | 2023.02.27 | S29W03 | |||||||||
| 13241 | 2023.02.28 2023.03.01 |
2 | 3 | 2 | N27E59 | 0070 | HSX | HSX |
 |
 |
area: 0090 location: N28E57 |
| 13240 | 2023.02.28 2023.03.01 |
2 | 3 | 1 | S16E41 | 0010 | BXO | BXO |
 |
 |
area: 0005 location: S14E42 |
| S8321 | 2023.02.28 | N41E03 | |||||||||
| S8322 | 2023.03.01 | S13W35 |
 |
||||||||
| 13242 | 2023.03.01 2023.03.02 |
14 | 6 | N10E66 | 0330 | DKO |
 |
 |
|||
| S8324 | 2023.03.01 | 7 | 3 | N18W22 | 0030 | CRO |
 |
 |
|||
| S8325 | 2023.03.01 | N17W02 |
 |
||||||||
| S8326 | 2023.03.02 | 3 | S20E24 | 0005 | AXX |
 |
|||||
| S8327 | 2023.03.02 | 3 | 1 | S09E33 | 0006 | AXX |
 |
||||
| S8328 | 2023.03.02 | 1 | 1 | S23E84 | 0350 | HKX |
 |
||||
| Total spot count: | 28 | 83 | 39 | ||||||||
| Sunspot number: | 88 | 233 | 169 | (total spot count + 10 * number of spotted regions) | |||||||
| Weighted SN: | 53 | 134 | 90 | (Sum of total spot count + classification weighting for each AR. Classification weighting: X=0, R=3, A/S=5, H/K=10) | |||||||
| Relative sunspot number (Wolf number): | 97 | 128 | 135 | ||||||||
| Month | Average solar flux | International sunspot number (WDC-SILSO) |
Smoothed sunspot number (4) | Average ap (3) |
|
|---|---|---|---|---|---|
| Measured | 1 AU | ||||
| 2014.02 | 170.3 (cycle peak) |
166.3 | 146.1 (SC24 peak) | 110.5 | 10.70 |
| 2014.04 | 143.9 | 144.8 | 112.5 | 116.4 (SC24 solar max) | 7.88 |
| 2017.09 | 91.3 | 92.3 | 43.6 | 18.2 (-1.3) | 18.22 (SC24 peak) |
| 2019.11 | 70.2 | 68.7 | 0.5 | 2.0 (-0.6) (Solar minimum using 365d smoothing: November 17, 2019) |
4.19 |
| 2019.12 | 70.8 | 68.6 | 1.6 | 1.8 (-0.2) (ISN 13 months smoothed solar minimum) |
3.22 |
| 2021.08 | 77.7 | 79.7 | 22.0 | 35.4 (+4.0) | 6.19 |
| 2021.09 | 87.0 | 88.2 | 51.3 | 40.2 (+4.8) | 6.33 |
| 2021.10 | 88.9 | 88.3 | 37.4 | 45.2 (+5.0) | 7.38 |
| 2021.11 | 86.2 | 84.4 | 34.8 | 50.8 (+5.6) | 9.83 |
| 2021.12 | 103.0 | 99.8 | 67.5 | 55.9 (+5.1) | 6.40 |
| 2022.01 | 103.8 | 100.5 | 55.3 | 60.1 (+4.2) | 8.92 |
| 2022.02 | 109.1 | 106.5 | 60.9 | 64.7 (+4.6) | 10.46 |
| 2022.03 | 117.0 | 115.8 | 78.6 | 68.7 (+4.0) | 10.20 |
| 2022.04 | 130.8 | 131.7 | 84.0 | 73.0 (+4.3) | 11.79 |
| 2022.05 | 133.8 | 136.8 | 96.5 | 77.2 (+4.2) | 7.48 |
| 2022.06 | 116.1 | 119.8 | 70.3 | 80.9 (+3.7) | 8.20 |
| 2022.07 | 125.4 | 129.5 | 91.4 | 86.5 (+5.6) | 9.51 |
| 2022.08 | 114.2 | 117.1 | 74.6 | 92.3 (+5.8) | 10.92 |
| 2022.09 | 135.1 | 136.5 | 96.0 | (97.0 projected, +4.7) | 12.18 |
| 2022.10 | 133.5 | 132.7 | 95.4 | (100.2 projected, +3.2) | 11.16 |
| 2022.11 | 123.4 | 120.7 | 77.6 | (103.0 projected, +2.8) | 9.33 |
| 2022.12 | 147.9 | 143.4 | 113.1 | (107.8 projected, +4.8) | 10.99 |
| 2023.01 | 182.4 | 176.6 | 143.6 | (113.8 projected, +6.0) | 8.73 |
| 2023.02 | 167.2 | 163.2 | 110.9 | (118.9 projected, +5.1) | 14.6 |
| 2023.03 | 165.4 (1) | 6.2 (2A) / 96.5 (2B) / 150.4 (2C) | (122.0 projected, +3.1) | (8.1) | |
| 2023.04 | (127.4 projected, +5.4) | ||||
| 2023.05 | (133.2 projected, +5.8) | ||||
| 2023.06 | (136.4 projected, +3.2) | ||||
| 2023.07 | (135.9 projected, -0.5) | ||||
| 2023.08 | (136.9 projected, +1.0) | ||||
| 2023.11 | (142.5 projected max SC25) | ||||
1) Running average based on the daily 20:00 UTC observed solar flux value at 2800 MHz
and any corrections applied to that measurement.
2A) Current impact on the monthly sunspot number based on the Boulder (NOAA/SWPC) sunspot number (accumulated daily sunspots / month days).
2B) Boulder SN current month average to date.
2C) STAR SDO 1K Wolf number 30 day average.
3) Running average based on the quicklook and definitive Potsdam WDC ap indices. Values in red
are based on the definitive international
GFZ Potsdam WDC ap indices.
4) Source: SIDC-SILSO.
This report has been prepared by Jan Alvestad. It is based on the analysis of data from whatever sources are available at the time the report is prepared. All time references are to Universal Time. Comments and suggestions are always welcome.
SDO images are courtesy of NASA/SDO and the AIA, EVE, and HMI science teams.
