:Product: 3-Day Forecast
:Issued: 2026 May 17 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 17-May 19 2026 is 5.00 (NOAA Scale
G1).

NOAA Kp index breakdown May 17-May 19 2026

May 17 May 18 May 19
00-03UT 3.33 3.67 4.33
03-06UT 4.00 3.33 3.67
06-09UT 4.67 (G1) 3.00 3.00
09-12UT 2.33 2.67 2.00
12-15UT 2.00 2.67 1.67
15-18UT 2.33 5.00 (G1) 2.00
18-21UT 3.00 3.33 3.00
21-00UT 3.67 3.33 3.33

Rationale: G1 (Minor) geomagnetic storms are expected on 17 May due to
the negative polarity CH HSS ongoing effects. G1 (Minor) storming levels
are likely on 18 May due to possible glancing blow of a CME from 16 May.

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 17-May 19 2026

May 17 May 18 May 19
S1 or greater 5% 5% 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 16 2026 1742 UTC.

Radio Blackout Forecast for May 17-May 19 2026

May 17 May 18 May 19
R1-R2 40% 40% 40%
R3 or greater 5% 5% 5%

Rationale: R1-R2 (Minor-Moderate) radio blackouts are likely through 19
May due to the flare potential and evolution of the active regions on
the visible disk.


--- MBSE BBS v1.1.7.2 (Linux-x86_64)
* Origin: Outpost BBS * Johnson City, TN (618:618/1)

:Product: 3-Day Forecast
:Issued: 2026 May 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 4 (below NOAA
Scale levels).
The greatest expected 3 hr Kp for May 20-May 22 2026 is 3.67 (below NOAA
Scale levels).

NOAA Kp index breakdown May 20-May 22 2026

May 20 May 21 May 22
00-03UT 2.67 2.67 2.67
03-06UT 2.33 2.00 3.67
06-09UT 2.00 2.33 2.00
09-12UT 2.00 2.33 0.67
12-15UT 2.00 2.33 1.67
15-18UT 2.00 2.33 1.67
18-21UT 2.00 2.33 2.33
21-00UT 2.00 2.67 2.33

Rationale: No G1 (Minor) or greater geomagnetic storms are expected. A
solar sector boundary crossing and positive polarity CH HSS influences
are possible through 21-22 May.

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 20-May 22 2026

May 20 May 21 May 22
S1 or greater 5% 5% 5%

Rationale: No S1 (Minor) or greater solar radiation storms are expected.


C. NOAA Radio Blackout Activity and Forecast

No radio blackouts were observed over the past 24 hours.

Radio Blackout Forecast for May 20-May 22 2026

May 20 May 21 May 22
R1-R2 20% 20% 25%
R3 or greater 5% 5% 5%

Rationale: There is a slight chance for R1-R2 (Minor-Moderate) radio
blackouts through 21 May, increasing to a chance on 22 May. R3 (Strong)
or greater events are not expected.


--- MBSE BBS v1.1.7.2 (Linux-x86_64)
* Origin: Outpost BBS * Johnson City, TN (618:618/1)

:Product: 3-Day Forecast
:Issued: 2026 May 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 3 (below NOAA
Scale levels).
The greatest expected 3 hr Kp for May 23-May 25 2026 is 2.67 (below NOAA
Scale levels).

NOAA Kp index breakdown May 23-May 25 2026

May 23 May 24 May 25
00-03UT 2.33 1.67 1.67
03-06UT 2.67 1.67 1.33
06-09UT 2.33 1.33 1.33
09-12UT 1.67 1.33 1.33
12-15UT 1.67 1.33 1.67
15-18UT 2.00 1.33 1.33
18-21UT 2.33 1.33 1.67
21-00UT 2.33 1.67 1.33

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-19 over the past 24 hours, was
below S-scale storm level thresholds.

Solar Radiation Storm Forecast for May 23-May 25 2026

May 23 May 24 May 25
S1 or greater 5% 5% 5%

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 22 2026 1029 UTC.

Radio Blackout Forecast for May 23-May 25 2026

May 23 May 24 May 25
R1-R2 25% 25% 25%
R3 or greater 5% 5% 5%

Rationale: There is a chance for R1-R2 (Minor-Moderate) radio blackouts
over 23-25 May.


--- MBSE BBS v1.1.7.2 (Linux-x86_64)
* Origin: Outpost BBS * Johnson City, TN (618:618/1)

:Product: 3-Day Forecast
:Issued: 2026 May 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 May 26-May 28 2026 is 3.67 (below NOAA
Scale levels).

NOAA Kp index breakdown May 26-May 28 2026

May 26 May 27 May 28
00-03UT 1.67 2.67 3.00
03-06UT 1.67 3.67 3.67
06-09UT 2.00 3.00 3.00
09-12UT 1.67 2.67 2.67
12-15UT 1.67 2.33 2.00
15-18UT 1.67 2.00 1.67
18-21UT 2.00 2.33 2.67
21-00UT 2.00 2.67 1.67

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 26-May 28 2026

May 26 May 27 May 28
S1 or greater 50% 5% 5%

Rationale: There is a chance for S1 (Minor) or greater solar radiation
storms due to activity beyond the NW limb.

C. NOAA Radio Blackout Activity and Forecast

No radio blackouts were observed over the past 24 hours.

Radio Blackout Forecast for May 26-May 28 2026

May 26 May 27 May 28
R1-R2 35% 35% 35%
R3 or greater 5% 5% 5%

Rationale: There is a chance for R1-R2 (Minor-Moderate) radio blackouts
all three days.


--- MBSE BBS v1.1.7.2 (Linux-x86_64)
* Origin: Outpost BBS * Johnson City, TN (618:618/1)

:Product: 3-Day Forecast
:Issued: 2026 May 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 4 (below NOAA
Scale levels).
The greatest expected 3 hr Kp for May 29-May 31 2026 is 4.00 (below NOAA
Scale levels).

NOAA Kp index breakdown May 29-May 31 2026

May 29 May 30 May 31
00-03UT 3.33 2.33 3.00
03-06UT 2.67 2.00 2.33
06-09UT 2.33 1.33 2.33
09-12UT 2.33 1.33 1.67
12-15UT 2.00 2.67 3.33
15-18UT 2.33 2.33 2.67
18-21UT 2.67 3.00 4.00
21-00UT 3.67 3.00 3.67

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 29-May 31 2026

May 29 May 30 May 31
S1 or greater 5% 5% 5%

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 29-May 31 2026

May 29 May 30 May 31
R1-R2 40% 40% 40%
R3 or greater 5% 5% 5%

Rationale: There is a chance for R1-R2 (Minor-Moderate) radio blackouts
through 31 May.


--- MBSE BBS v1.1.7.2 (Linux-x86_64)
* Origin: Outpost BBS * Johnson City, TN (618:618/1)

:Product: 3-Day Forecast
:Issued: 2026 Jun 01 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 Jun 01-Jun 03 2026 is 4.00 (below NOAA
Scale levels).

NOAA Kp index breakdown Jun 01-Jun 03 2026

Jun 01 Jun 02 Jun 03
00-03UT 3.67 2.67 2.00
03-06UT 3.00 2.33 3.33
06-09UT 2.33 2.00 4.00
09-12UT 2.00 1.33 3.00
12-15UT 1.67 1.33 2.67
15-18UT 2.00 2.00 2.33
18-21UT 2.00 2.00 2.33
21-00UT 2.33 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 Jun 01-Jun 03 2026

Jun 01 Jun 02 Jun 03
S1 or greater 5% 5% 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 Jun 01-Jun 03 2026

Jun 01 Jun 02 Jun 03
R1-R2 25% 25% 20%
R3 or greater 5% 5% 1%

Rationale: There is a chance for R1-R2 (Minor-Moderate) radio blackouts
on 01-02 Jun, with a slight chance for R1-R2 events on 03 Jun.


--- MBSE BBS v1.1.7.2 (Linux-x86_64)
* Origin: Outpost BBS * Johnson City, TN (618:618/1)

:Product: 3-Day Forecast
:Issued: 2026 Jun 04 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 Jun 04-Jun 06 2026 is 7.00 (NOAA Scale
G3).

NOAA Kp index breakdown Jun 04-Jun 06 2026

Jun 04 Jun 05 Jun 06
00-03UT 2.67 7.00 (G3) 4.33
03-06UT 3.00 6.33 (G2) 3.67
06-09UT 4.00 6.00 (G2) 2.67
09-12UT 2.67 4.67 (G1) 2.67
12-15UT 3.67 4.33 3.00
15-18UT 6.33 (G2) 4.67 (G1) 3.33
18-21UT 6.67 (G3) 5.00 (G1) 4.00
21-00UT 5.67 (G2) 4.33 3.67

Rationale: G2-G3 (Moderate) or greater geomagnetic storms are likely on
04-05 Jun due to a combination of CMEs that left the Sun on 03-04 Jun.

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 Jun 04-Jun 06 2026

Jun 04 Jun 05 Jun 06
S1 or greater 10% 10% 10%

Rationale: There is a slight chance for S1 (Minor) or greater solar
radiation storms over the next three days.

C. NOAA Radio Blackout Activity and Forecast

Radio blackouts reaching the R2 levels were observed over the past 24
hours. The largest was at Jun 03 2026 1127 UTC.

Radio Blackout Forecast for Jun 04-Jun 06 2026

Jun 04 Jun 05 Jun 06
R1-R2 60% 60% 60%
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 06 June.


--- MBSE BBS v1.1.7.2 (Linux-x86_64)
* Origin: Outpost BBS * Johnson City, TN (618:618/1)

:Product: 3-Day Forecast
:Issued: 2026 Jun 07 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 Jun 07-Jun 09 2026 is 7.00 (NOAA Scale
G3).

NOAA Kp index breakdown Jun 07-Jun 09 2026

Jun 07 Jun 08 Jun 09
00-03UT 3.00 2.33 6.33 (G2)
03-06UT 2.67 2.00 5.33 (G1)
06-09UT 2.67 3.00 5.00 (G1)
09-12UT 2.00 4.33 4.33
12-15UT 2.00 5.33 (G1) 3.00
15-18UT 2.00 5.67 (G2) 3.33
18-21UT 2.33 7.00 (G3) 3.33
21-00UT 2.33 6.33 (G2) 3.67

Rationale: Periods of G1-G3 (Minor-Strong) geomagnetic storming are
likely on 08 Jun, with G1-G2 (Minor-Moderate) storm periods likely on 09
Jun, following the anticipated arrival of a CME that left the Sun on 06
Jun.

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 Jun 07-Jun 09 2026

Jun 07 Jun 08 Jun 09
S1 or greater 15% 25% 10%

Rationale: There is a slight chance for S1 (Minor) solar radiation
storms on 07 and 09 Jun, with a chance for S1 levels on 08 Jun following
the anticipated shock arrival of the 06 June CME.

C. NOAA Radio Blackout Activity and Forecast

Radio blackouts reaching the R1 levels were observed over the past 24
hours. The largest was at Jun 06 2026 1401 UTC.

Radio Blackout Forecast for Jun 07-Jun 09 2026

Jun 07 Jun 08 Jun 09
R1-R2 55% 55% 55%
R3 or greater 10% 10% 10%

Rationale: R1-R2 (Minor-Moderate) radio blackouts are likely, with a
slight chance for R3 (Strong) or greater events, over 07-09 Jun.


--- MBSE BBS v1.1.7.2 (Linux-x86_64)
* Origin: Outpost BBS * Johnson City, TN (618:618/1)

:Product: 3-Day Forecast
:Issued: 2026 Jun 10 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 Jun 10-Jun 12 2026 is 4.00 (below NOAA
Scale levels).

NOAA Kp index breakdown Jun 10-Jun 12 2026

Jun 10 Jun 11 Jun 12
00-03UT 3.67 2.00 3.67
03-06UT 2.67 2.00 4.00
06-09UT 2.67 3.00 4.00
09-12UT 2.00 2.67 2.33
12-15UT 2.67 3.00 2.00
15-18UT 2.00 3.00 2.67
18-21UT 2.67 3.00 2.00
21-00UT 3.00 2.67 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 Jun 10-Jun 12 2026

Jun 10 Jun 11 Jun 12
S1 or greater 10% 10% 10%

Rationale: A slight chance of solar radiation storms are expected
through 12 Jun.

C. NOAA Radio Blackout Activity and Forecast

No radio blackouts were observed over the past 24 hours.

Radio Blackout Forecast for Jun 10-Jun 12 2026

Jun 10 Jun 11 Jun 12
R1-R2 55% 55% 55%
R3 or greater 15% 15% 15%

Rationale: Solar activity is likely to be moderate (R1-R2,
Minor-Moderate) with a slight chance for an X-class flares (R3-Strong)
through 12 Jun, mainly due to the flare potential of Regions 4464
(S12E11, Ehi/beta) and 4465.


--- MBSE BBS v1.1.7.2 (Linux-x86_64)
* Origin: Outpost BBS * Johnson City, TN (618:618/1)

:Product: 3-Day Forecast
:Issued: 2026 Jun 13 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 Jun 13-Jun 15 2026 is 5.67 (NOAA Scale
G2).

NOAA Kp index breakdown Jun 13-Jun 15 2026

Jun 13 Jun 14 Jun 15
00-03UT 3.33 4.67 (G1) 3.00
03-06UT 4.67 (G1) 4.00 2.33
06-09UT 5.67 (G2) 3.33 3.67
09-12UT 3.00 3.33 2.67
12-15UT 4.67 (G1) 2.67 2.67
15-18UT 5.00 (G1) 2.67 2.00
18-21UT 4.33 3.67 2.33
21-00UT 4.33 4.00 2.33

Rationale: Geomagnetic field conditions are likely to reach G2
(Moderate) geomagnetic storm levels on 13 Jun due to the persistence of
the high-speed stream combined with the anticipated arrival of CMEs that
left the Sun over 09 Jun and 11 Jun. Conditions are expected to decrease
on 14 Jun, with isolated G1 (Minor) storming periods still likely, as
CME influences wane.

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 Jun 13-Jun 15 2026

Jun 13 Jun 14 Jun 15
S1 or greater 5% 5% 5%

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 Jun 13-Jun 15 2026

Jun 13 Jun 14 Jun 15
R1-R2 35% 35% 35%
R3 or greater 5% 5% 5%

Rationale: There is a chance for R1-R2 (Minor-Moderate) radio blackouts
on 13-15 Jun, primarily due to the potential of Regions 4464 and 4465.


--- MBSE BBS v1.1.7.2 (Linux-x86_64)
* Origin: Outpost BBS * Johnson City, TN (618:618/1)

:Product: 3-Day Forecast
:Issued: 2026 Jun 16 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 Jun 16-Jun 18 2026 is 4.00 (below NOAA
Scale levels).

NOAA Kp index breakdown Jun 16-Jun 18 2026

Jun 16 Jun 17 Jun 18
00-03UT 2.67 3.00 3.33
03-06UT 3.67 2.00 3.00
06-09UT 3.67 2.00 2.33
09-12UT 2.67 1.67 2.00
12-15UT 1.67 1.33 1.67
15-18UT 1.67 2.67 1.33
18-21UT 1.67 4.00 1.33
21-00UT 2.00 3.00 2.67

Rationale: No G1 (Minor) or greater geomagnetic storms are expected
through 18 Jun.

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 Jun 16-Jun 18 2026

Jun 16 Jun 17 Jun 18
S1 or greater 1% 1% 1%

Rationale: No S1 (Minor) or greater solar radiation storms are expected. through 18 Jun.

C. NOAA Radio Blackout Activity and Forecast

No radio blackouts were observed over the past 24 hours.

Radio Blackout Forecast for Jun 16-Jun 18 2026

Jun 16 Jun 17 Jun 18
R1-R2 20% 20% 20%
R3 or greater 1% 1% 1%

Rationale: There is a slight chance for R1-R2 (Minor-Moderate) radio
blackouts through 18 Jun.


--- MBSE BBS v1.1.7.2 (Linux-x86_64)
* Origin: Outpost BBS * Johnson City, TN (618:618/1)