-
3 Day Space Weather Forec
From
Sean Dennis@VERT/IISS to
All on Monday, May 11, 2026 00:19:00
:Product: 3-Day Forecast
:Issued: 2026 May 11 0030 UTC
# Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center
#
A. NOAA Geomagnetic Activity Observation and Forecast
The greatest observed 3 hr Kp over the past 24 hours was 2 (below NOAA
Scale levels).
The greatest expected 3 hr Kp for May 11-May 13 2026 is 2.67 (below NOAA
Scale levels).
NOAA Kp index breakdown May 11-May 13 2026
May 11 May 12 May 13
00-03UT 1.67 1.67 1.67
03-06UT 2.67 1.67 2.67
06-09UT 2.67 1.33 2.67
09-12UT 1.67 1.33 2.33
12-15UT 1.33 1.33 2.33
15-18UT 1.33 0.67 2.00
18-21UT 2.00 1.67 2.33
21-00UT 2.67 1.67 2.67
Rationale: No G1 (Minor) or greater geomagnetic storms are expected. No significant transient or recurrent solar wind features are forecast.
B. NOAA Solar Radiation Activity Observation and Forecast
Solar radiation, as observed by NOAA GOES-19 over the past 24 hours, was
below S-scale storm level thresholds.
Solar Radiation Storm Forecast for May 11-May 13 2026
May 11 May 12 May 13
S1 or greater 20% 20% 20%
Rationale: No S1 (Minor) or greater solar radiation storms are expected.
No significant active region activity favorable for radiation storm
production is forecast.
C. NOAA Radio Blackout Activity and Forecast
Radio blackouts reaching the R2 levels were observed over the past 24
hours. The largest was at May 10 2026 1339 UTC.
Radio Blackout Forecast for May 11-May 13 2026
May 11 May 12 May 13
R1-R2 45% 45% 45%
R3 or greater 20% 20% 20%
Rationale: There exists a chance for R1-R2 (Minor-Moderate) radio
blackouts, with a slight chance for R3 (Strong), over 11-13 May.
--- MBSE BBS v1.1.7.2 (Linux-x86_64)
* Origin: Outpost BBS * Johnson City, TN (1:18/200)
-
From
Sean Dennis@VERT/IISS to
All on Saturday, April 11, 2026 00:19:00
:Product: 3-Day Forecast
:Issued: 2026 Apr 11 0030 UTC
# Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center
#
A. NOAA Geomagnetic Activity Observation and Forecast
The greatest observed 3 hr Kp over the past 24 hours was 4 (below NOAA
Scale levels).
The greatest expected 3 hr Kp for Apr 11-Apr 13 2026 is 4.67 (NOAA Scale
G1).
NOAA Kp index breakdown Apr 11-Apr 13 2026
Apr 11 Apr 12 Apr 13
00-03UT 3.67 3.67 2.67
03-06UT 4.67 (G1) 3.67 2.67
06-09UT 4.00 3.67 3.00
09-12UT 4.00 2.67 2.67
12-15UT 3.00 2.67 1.67
15-18UT 2.67 1.67 1.67
18-21UT 4.00 2.67 2.00
21-00UT 4.67 (G1) 3.00 2.67
Rationale: Periods of G1 (Minor) storm levels are expected on 11 Apr due
to +CH HSS influences.
B. NOAA Solar Radiation Activity Observation and Forecast
Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was
below S-scale storm level thresholds.
Solar Radiation Storm Forecast for Apr 11-Apr 13 2026
Apr 11 Apr 12 Apr 13
S1 or greater 1% 1% 1%
Rationale: No S1 (Minor) or greater solar radiation storms are expected.
No significant active region activity favorable for radiation storm
production is forecast.
C. NOAA Radio Blackout Activity and Forecast
No radio blackouts were observed over the past 24 hours.
Radio Blackout Forecast for Apr 11-Apr 13 2026
Apr 11 Apr 12 Apr 13
R1-R2 5% 5% 5%
R3 or greater 1% 1% 1%
Rationale: No R1 (Minor) or greater radio blackouts are expected. No significant active region flare activity is forecast.
--- MBSE BBS v1.1.7.2 (Linux-x86_64)
* Origin: Outpost BBS * Johnson City, TN (1:18/200)
-
From
Sean Dennis@VERT/IISS to
All on Tuesday, April 14, 2026 00:19:00
:Product: 3-Day Forecast
:Issued: 2026 Apr 14 0030 UTC
# Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center
#
A. NOAA Geomagnetic Activity Observation and Forecast
The greatest observed 3 hr Kp over the past 24 hours was 1 (below NOAA
Scale levels).
The greatest expected 3 hr Kp for Apr 14-Apr 16 2026 is 4.00 (below NOAA
Scale levels).
NOAA Kp index breakdown Apr 14-Apr 16 2026
Apr 14 Apr 15 Apr 16
00-03UT 1.67 2.67 1.67
03-06UT 2.67 3.00 2.67
06-09UT 1.67 4.00 2.67
09-12UT 1.67 2.67 2.33
12-15UT 1.00 2.67 1.67
15-18UT 0.67 1.67 1.67
18-21UT 1.67 1.67 1.67
21-00UT 2.00 2.00 2.33
Rationale: No G1 (Minor) or greater geomagnetic storms are expected. No significant transient or recurrent solar wind features are forecast.
B. NOAA Solar Radiation Activity Observation and Forecast
Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was
below S-scale storm level thresholds.
Solar Radiation Storm Forecast for Apr 14-Apr 16 2026
Apr 14 Apr 15 Apr 16
S1 or greater 1% 1% 1%
Rationale: No S1 (Minor) or greater solar radiation storms are expected.
No significant active region activity favorable for radiation storm
production is forecast.
C. NOAA Radio Blackout Activity and Forecast
No radio blackouts were observed over the past 24 hours.
Radio Blackout Forecast for Apr 14-Apr 16 2026
Apr 14 Apr 15 Apr 16
R1-R2 10% 10% 10%
R3 or greater 1% 1% 1%
Rationale: There is a slight chance for R1-R2 (Minor-Moderate) radio
blackouts on 14-16 Apr.
--- MBSE BBS v1.1.7.2 (Linux-x86_64)
* Origin: Outpost BBS * Johnson City, TN (1:18/200)
-
From
Sean Dennis@VERT/IISS to
All on Friday, April 17, 2026 00:19:00
:Product: 3-Day Forecast
:Issued: 2026 Apr 16 1230 UTC
# Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center
#
A. NOAA Geomagnetic Activity Observation and Forecast
The greatest observed 3 hr Kp over the past 24 hours was 2 (below NOAA
Scale levels).
The greatest expected 3 hr Kp for Apr 16-Apr 18 2026 is 6.00 (NOAA Scale
G2).
NOAA Kp index breakdown Apr 16-Apr 18 2026
Apr 16 Apr 17 Apr 18
00-03UT 0.67 2.33 6.00 (G2)
03-06UT 1.00 2.67 6.00 (G2)
06-09UT 1.00 2.67 5.00 (G1)
09-12UT 0.67 2.00 4.00
12-15UT 1.67 1.33 3.67
15-18UT 1.67 2.67 3.33
18-21UT 1.67 4.33 3.00
21-00UT 2.33 5.67 (G2) 4.33
Rationale: G1-G2 (Minor-Moderate) geomagnetic storms are likely on 17-18
Apr due to the anticipated arrival of a negative polarity CH HSS CIR.
B. NOAA Solar Radiation Activity Observation and Forecast
Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was
below S-scale storm level thresholds.
Solar Radiation Storm Forecast for Apr 16-Apr 18 2026
Apr 16 Apr 17 Apr 18
S1 or greater 1% 1% 1%
Rationale: No S1 (Minor) or greater solar radiation storms are expected.
No significant active region activity favorable for radiation storm
production is forecast.
C. NOAA Radio Blackout Activity and Forecast
No radio blackouts were observed over the past 24 hours.
Radio Blackout Forecast for Apr 16-Apr 18 2026
Apr 16 Apr 17 Apr 18
R1-R2 30% 30% 30%
R3 or greater 5% 5% 5%
Rationale: There is a chance for R1-R2 (Minor-Moderate) radio blackouts
through 18 Apr, mostly due to the flare potential of Region 4419.
--- MBSE BBS v1.1.7.2 (Linux-x86_64)
* Origin: Outpost BBS * Johnson City, TN (1:18/200)
-
From
Sean Dennis@VERT/IISS to
All on Monday, April 20, 2026 00:19:00
:Product: 3-Day Forecast
:Issued: 2026 Apr 20 0030 UTC
# Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center
#
A. NOAA Geomagnetic Activity Observation and Forecast
The greatest observed 3 hr Kp over the past 24 hours was 6 (NOAA Scale
G2).
The greatest expected 3 hr Kp for Apr 20-Apr 22 2026 is 4.00 (below NOAA
Scale levels).
NOAA Kp index breakdown Apr 20-Apr 22 2026
Apr 20 Apr 21 Apr 22
00-03UT 3.67 3.33 2.67
03-06UT 3.67 4.00 2.00
06-09UT 3.33 3.00 2.33
09-12UT 3.33 2.67 2.00
12-15UT 3.33 2.33 2.00
15-18UT 2.00 3.00 2.33
18-21UT 3.33 2.67 2.00
21-00UT 3.33 2.33 2.00
Rationale: No G1 (Minor) or greater geomagnetic storms are expected as
the CH HSS ongoing effect wanes.
B. NOAA Solar Radiation Activity Observation and Forecast
Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was
below S-scale storm level thresholds.
Solar Radiation Storm Forecast for Apr 20-Apr 22 2026
Apr 20 Apr 21 Apr 22
S1 or greater 1% 1% 1%
Rationale: No S1 (Minor) or greater solar radiation storms are expected.
No significant active region activity favorable for radiation storm
production is forecast.
C. NOAA Radio Blackout Activity and Forecast
No radio blackouts were observed over the past 24 hours.
Radio Blackout Forecast for Apr 20-Apr 22 2026
Apr 20 Apr 21 Apr 22
R1-R2 5% 5% 5%
R3 or greater 1% 1% 1%
Rationale: No R1 (Minor) or greater radio blackouts are expected. No significant active region flare activity is forecast.
--- MBSE BBS v1.1.7.2 (Linux-x86_64)
* Origin: Outpost BBS * Johnson City, TN (1:18/200)
-
From
Sean Dennis@VERT/IISS to
All on Thursday, April 23, 2026 00:19:00
:Product: 3-Day Forecast
:Issued: 2026 Apr 23 0030 UTC
# Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center
#
A. NOAA Geomagnetic Activity Observation and Forecast
The greatest observed 3 hr Kp over the past 24 hours was 2 (below NOAA
Scale levels).
The greatest expected 3 hr Kp for Apr 23-Apr 25 2026 is 3.00 (below NOAA
Scale levels).
NOAA Kp index breakdown Apr 23-Apr 25 2026
Apr 23 Apr 24 Apr 25
00-03UT 2.33 2.33 2.33
03-06UT 2.00 2.67 2.67
06-09UT 2.00 2.67 2.33
09-12UT 2.00 1.67 2.00
12-15UT 0.67 1.33 1.33
15-18UT 2.00 2.00 1.67
18-21UT 2.67 2.00 2.00
21-00UT 3.00 2.33 2.67
Rationale: No G1 (Minor) or greater geomagnetic storms are expected. No significant transient or recurrent solar wind features are forecast.
B. NOAA Solar Radiation Activity Observation and Forecast
Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was
below S-scale storm level thresholds.
Solar Radiation Storm Forecast for Apr 23-Apr 25 2026
Apr 23 Apr 24 Apr 25
S1 or greater 1% 1% 1%
Rationale: No S1 (Minor) or greater solar radiation storms are expected.
No significant active region activity favorable for radiation storm
production is forecast.
C. NOAA Radio Blackout Activity and Forecast
No radio blackouts were observed over the past 24 hours.
Radio Blackout Forecast for Apr 23-Apr 25 2026
Apr 23 Apr 24 Apr 25
R1-R2 10% 10% 10%
R3 or greater 1% 1% 1%
Rationale: A slight chance for R1-R2 (Minor-Moderate) radio blackouts
will persist through 25 April primarily due to the flare potential
exhibited by Region 4420.
--- MBSE BBS v1.1.7.2 (Linux-x86_64)
* Origin: Outpost BBS * Johnson City, TN (1:18/200)
-
From
Sean Dennis@VERT/IISS to
All on Sunday, April 26, 2026 00:19:00
:Product: 3-Day Forecast
:Issued: 2026 Apr 26 0030 UTC
# Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center
#
A. NOAA Geomagnetic Activity Observation and Forecast
The greatest observed 3 hr Kp over the past 24 hours was 3 (below NOAA
Scale levels).
The greatest expected 3 hr Kp for Apr 26-Apr 28 2026 is 4.67 (NOAA Scale
G1).
NOAA Kp index breakdown Apr 26-Apr 28 2026
Apr 26 Apr 27 Apr 28
00-03UT 4.67 (G1) 3.67 2.33
03-06UT 4.33 3.00 2.00
06-09UT 3.33 2.67 2.00
09-12UT 3.33 2.33 2.00
12-15UT 2.33 2.00 2.33
15-18UT 2.33 2.33 2.00
18-21UT 3.00 3.33 2.00
21-00UT 3.33 3.33 2.00
Rationale: Isolated G1-G2 (Minor-Moderate) geomagnetic storming
conditions are possible (G1 likely with a chance for G2)early 26 Apr in response to the arrival of the glancing CMEs.
B. NOAA Solar Radiation Activity Observation and Forecast
Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was
below S-scale storm level thresholds.
Solar Radiation Storm Forecast for Apr 26-Apr 28 2026
Apr 26 Apr 27 Apr 28
S1 or greater 10% 10% 10%
Rationale: There is a chance to exceed the S1 (Minor) solar radiation
storm thresholds due to the flare potential of Region 4419 further
beyond the western limb, and Region 4420 near the central solar
meridian.
C. NOAA Radio Blackout Activity and Forecast
Radio blackouts reaching the R1 levels were observed over the past 24
hours. The largest was at Apr 25 2026 0759 UTC.
Radio Blackout Forecast for Apr 26-Apr 28 2026
Apr 26 Apr 27 Apr 28
R1-R2 55% 55% 55%
R3 or greater 15% 15% 15%
Rationale: R1-R2 (Minor-Moderate) radio blackouts are likely, with a
slight chance for R3 (Strong or greater) events through 28 Apr,
primarily driven by the complexity of Regions 4420, 4423, and 4425.
--- MBSE BBS v1.1.7.2 (Linux-x86_64)
* Origin: Outpost BBS * Johnson City, TN (1:18/200)
-
From
Sean Dennis@VERT/IISS to
All on Wednesday, April 29, 2026 00:19:00
:Product: 3-Day Forecast
:Issued: 2026 Apr 29 0030 UTC
# Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center
#
A. NOAA Geomagnetic Activity Observation and Forecast
The greatest observed 3 hr Kp over the past 24 hours was 1 (below NOAA
Scale levels).
The greatest expected 3 hr Kp for Apr 29-May 01 2026 is 4.00 (below NOAA
Scale levels).
NOAA Kp index breakdown Apr 29-May 01 2026
Apr 29 Apr 30 May 01
00-03UT 0.33 4.00 3.00
03-06UT 0.67 3.33 2.67
06-09UT 1.33 2.67 2.67
09-12UT 1.33 3.00 2.33
12-15UT 1.00 2.33 2.00
15-18UT 1.00 2.33 2.00
18-21UT 1.33 2.00 2.00
21-00UT 1.67 3.00 2.33
Rationale: No G1 (Minor) or greater geomagnetic storms are expected. No significant transient or recurrent solar wind features are forecast.
B. NOAA Solar Radiation Activity Observation and Forecast
Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was
below S-scale storm level thresholds.
Solar Radiation Storm Forecast for Apr 29-May 01 2026
Apr 29 Apr 30 May 01
S1 or greater 15% 15% 15%
Rationale: There is a slight chance the greater than 10 MeV proton flux
could reach S1 (Minor) levels, but is mainly expected to remain at
background levels 29-30 Apr and 01 May.
C. NOAA Radio Blackout Activity and Forecast
Radio blackouts reaching the R1 levels were observed over the past 24
hours. The largest was at Apr 28 2026 1353 UTC.
Radio Blackout Forecast for Apr 29-May 01 2026
Apr 29 Apr 30 May 01
R1-R2 70% 70% 70%
R3 or greater 20% 20% 20%
Rationale: There is a high likelihood for R1/R2 (Minor/Moderate) radio blackouts, and a slight chance for R3 (Strong or greater) events through
01 May, due primarily to the complexity of regions 4420 and 4425.
--- MBSE BBS v1.1.7.2 (Linux-x86_64)
* Origin: Outpost BBS * Johnson City, TN (1:18/200)
-
From
Sean Dennis@VERT/IISS to
All on Saturday, May 02, 2026 00:19:00
:Product: 3-Day Forecast
:Issued: 2026 May 02 0030 UTC
# Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center
#
A. NOAA Geomagnetic Activity Observation and Forecast
The greatest observed 3 hr Kp over the past 24 hours was 4 (below NOAA
Scale levels).
The greatest expected 3 hr Kp for May 02-May 04 2026 is 4.00 (below NOAA
Scale levels).
NOAA Kp index breakdown May 02-May 04 2026
May 02 May 03 May 04
00-03UT 2.33 2.67 2.67
03-06UT 2.33 3.00 3.00
06-09UT 3.00 4.00 2.67
09-12UT 2.67 2.67 2.67
12-15UT 2.00 2.33 1.67
15-18UT 2.00 1.67 1.67
18-21UT 1.67 1.67 0.67
21-00UT 2.67 2.67 2.67
Rationale: No G1 (Minor) or greater geomagnetic storms are expected. No significant transient or recurrent solar wind features are forecast.
B. NOAA Solar Radiation Activity Observation and Forecast
Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was
below S-scale storm level thresholds.
Solar Radiation Storm Forecast for May 02-May 04 2026
May 02 May 03 May 04
S1 or greater 1% 1% 1%
Rationale: No S1 (Minor) or greater solar radiation storms are expected.
No significant active region activity favorable for radiation storm
production is forecast.
C. NOAA Radio Blackout Activity and Forecast
No radio blackouts were observed over the past 24 hours.
Radio Blackout Forecast for May 02-May 04 2026
May 02 May 03 May 04
R1-R2 40% 40% 40%
R3 or greater 5% 5% 5%
Rationale: There exists a chance for R1-R2 (Minor-Moderate) radio
blackouts over 02-04 May due to the potential from multiple complex
regions on the Suns visible disk.
--- MBSE BBS v1.1.7.2 (Linux-x86_64)
* Origin: Outpost BBS * Johnson City, TN (1:18/200)
-
From
Sean Dennis@VERT/IISS to
All on Tuesday, May 05, 2026 00:19:00
:Product: 3-Day Forecast
:Issued: 2026 May 05 0030 UTC
# Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center
#
A. NOAA Geomagnetic Activity Observation and Forecast
The greatest observed 3 hr Kp over the past 24 hours was 6 (NOAA Scale
G2).
The greatest expected 3 hr Kp for May 05-May 07 2026 is 5.67 (NOAA Scale
G2).
NOAA Kp index breakdown May 05-May 07 2026
May 05 May 06 May 07
00-03UT 5.33 (G1) 2.67 3.33
03-06UT 5.67 (G2) 2.33 3.67
06-09UT 5.00 (G1) 2.00 3.00
09-12UT 4.00 1.33 2.33
12-15UT 3.00 1.67 2.33
15-18UT 2.33 2.33 3.33
18-21UT 2.00 2.00 3.33
21-00UT 2.67 2.67 3.67
Rationale: Isolated G1-G2 (Minor-Moderate) storming periods are possible
early on 05 May as CME/CH HSS effects persist.
B. NOAA Solar Radiation Activity Observation and Forecast
Solar radiation, as observed by NOAA GOES-19 over the past 24 hours, was
below S-scale storm level thresholds.
Solar Radiation Storm Forecast for May 05-May 07 2026
May 05 May 06 May 07
S1 or greater 5% 1% 1%
Rationale: No S1 (Minor) or greater solar radiation storms are expected.
No significant active region activity favorable for radiation storm
production is forecast.
C. NOAA Radio Blackout Activity and Forecast
Radio blackouts reaching the R1 levels were observed over the past 24
hours. The largest was at May 04 2026 0133 UTC.
Radio Blackout Forecast for May 05-May 07 2026
May 05 May 06 May 07
R1-R2 30% 30% 30%
R3 or greater 5% 5% 5%
Rationale: There is a chance for isolated R1-R2 (Minor-Moderate) radio blackouts on 05-07 May, primarily due to the flare potential of Region
4429.
--- MBSE BBS v1.1.7.2 (Linux-x86_64)
* Origin: Outpost BBS * Johnson City, TN (1:18/200)
-
From
Sean Dennis@VERT/IISS to
All on Friday, May 08, 2026 00:19:00
:Product: 3-Day Forecast
:Issued: 2026 May 08 0030 UTC
# Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center
#
A. NOAA Geomagnetic Activity Observation and Forecast
The greatest observed 3 hr Kp over the past 24 hours was 3 (below NOAA
Scale levels).
The greatest expected 3 hr Kp for May 08-May 10 2026 is 4.00 (below NOAA
Scale levels).
NOAA Kp index breakdown May 08-May 10 2026
May 08 May 09 May 10
00-03UT 2.67 2.67 2.67
03-06UT 3.67 3.67 2.67
06-09UT 4.00 3.00 2.00
09-12UT 2.67 2.67 2.00
12-15UT 3.67 2.67 2.00
15-18UT 1.67 1.67 1.67
18-21UT 2.33 2.00 1.67
21-00UT 2.67 2.67 2.00
Rationale: No G1 (Minor) or greater geomagnetic storms are expected.
B. NOAA Solar Radiation Activity Observation and Forecast
Solar radiation, as observed by NOAA GOES-19 over the past 24 hours, was
below S-scale storm level thresholds.
Solar Radiation Storm Forecast for May 08-May 10 2026
May 08 May 09 May 10
S1 or greater 1% 1% 1%
Rationale: No S1 (Minor) or greater solar radiation storms are expected.
No significant active region activity favorable for radiation storm
production is forecast.
C. NOAA Radio Blackout Activity and Forecast
Radio blackouts reaching the R1 levels were observed over the past 24
hours. The largest was at May 07 2026 1514 UTC.
Radio Blackout Forecast for May 08-May 10 2026
May 08 May 09 May 10
R1-R2 45% 45% 45%
R3 or greater 10% 10% 10%
Rationale: There exists a chance for R1-R2 (Minor-Moderate) radio
blackouts, and a slight chance for R3 (Strong), over 08-10 May.
--- MBSE BBS v1.1.7.2 (Linux-x86_64)
* Origin: Outpost BBS * Johnson City, TN (1:18/200)