| TYPE | RADIO BLACKOUT | SOLAR STORM | GEO STORM |
|---|---|---|---|
| SCALE | 1-2: 5%, 3-5: 45% | 5% | 0 |
| TEXT | None | S1 or < | none |
| TYPE | RADIO BLACKOUT | SOLAR STORM | GEO STORM |
|---|---|---|---|
| SCALE | 0 | 0 | 0 |
| TEXT | none | none | none |
| TYPE | RADIO BLACKOUT | SOLAR STORM | GEO STORM |
|---|---|---|---|
| SCALE | 1-2: 5%, 3-5: 5% | 5% | 0 |
| TEXT | None | S1 or < | none |
:Product: 3-Day Forecast
:Issued: 2026 May 03 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 03-May 05 2026 is 4.00 (below NOAA
Scale levels).
NOAA Kp index breakdown May 03-May 05 2026
May 03 May 04 May 05
00-03UT 2.67 2.67 2.67
03-06UT 3.00 3.00 2.67
06-09UT 4.00 2.67 2.00
09-12UT 2.67 2.67 2.00
12-15UT 2.33 1.67 1.67
15-18UT 1.67 1.67 1.67
18-21UT 1.67 0.67 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-18 over the past 24 hours, was
below S-scale storm level thresholds.
Solar Radiation Storm Forecast for May 03-May 05 2026
May 03 May 04 May 05
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 03-May 05 2026
May 03 May 04 May 05
R1-R2 45% 45% 45%
R3 or greater 5% 5% 5%
Rationale: There exists a chance for R1-R2 (Minor-Moderate) radio
blackouts over 03-05 May due to the flare potential from multiple
complex active regions on the Suns visible disk.
Updated last 2026/05/03 05:10 UTC
-------------------
Product ID: TIIA
Issued: 2026-05-02 11:11:38.977
Message Follows:
Space Weather Message Code: ALTTP2
Serial Number: 1482
Issue Time: 2026 May 02 1111 UTC
ALERT: Type II Radio Emission
Begin Time: 2026 May 02 1051 UTC
Estimated Velocity: 641 km/s
Comment: Likely associated with C-class flare acitivity originating from AR 4420 on the west limb.
Description: Type II emissions occur in association with eruptions on the sun and typically indicate a coronal mass ejection is associated with a flare event.
-------------------
Product ID: TIIA
Issued: 2026-05-01 15:50:32.247
Message Follows:
Space Weather Message Code: ALTTP2
Serial Number: 1481
Issue Time: 2026 May 01 1550 UTC
ALERT: Type II Radio Emission
Begin Time: 2026 May 01 1535 UTC
Estimated Velocity: 593 km/s
Description: Type II emissions occur in association with eruptions on the sun and typically indicate a coronal mass ejection is associated with a flare event.
-------------------
Product ID: K05A
Issued: 2026-04-30 23:59:26.927
Message Follows:
Space Weather Message Code: ALTK05
Serial Number: 2013
Issue Time: 2026 Apr 30 2359 UTC
ALERT: Geomagnetic K-index of 5
Threshold Reached: 2026 Apr 30 2359 UTC
Synoptic Period: 2100-2400 UTC
Active Warning: Yes
NOAA Scale: G1 - Minor
NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation
Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.
-------------------
Product ID: K04W
Issued: 2026-04-30 23:11:27.400
Message Follows:
Space Weather Message Code: WARK04
Serial Number: 5332
Issue Time: 2026 Apr 30 2311 UTC
EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5331
Valid From: 2026 Apr 30 2005 UTC
Now Valid Until: 2026 May 01 1500 UTC
Warning Condition: Persistence
NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation
Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.
-------------------
Product ID: K05W
Issued: 2026-04-30 23:09:26.960
Message Follows:
Space Weather Message Code: WARK05
Serial Number: 2230
Issue Time: 2026 Apr 30 2309 UTC
WARNING: Geomagnetic K-index of 5 expected
Valid From: 2026 Apr 30 2309 UTC
Valid To: 2026 May 01 0900 UTC
Warning Condition: Onset
NOAA Scale: G1 - Minor
NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation
Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.
-------------------
Product ID: K04A
Issued: 2026-04-30 20:35:36.850
Message Follows:
Space Weather Message Code: ALTK04
Serial Number: 2653
Issue Time: 2026 Apr 30 2035 UTC
ALERT: Geomagnetic K-index of 4
Threshold Reached: 2026 Apr 30 2035 UTC
Synoptic Period: 1800-2100 UTC
Active Warning: Yes
NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation
Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.
-------------------
Product ID: K04W
Issued: 2026-04-30 20:06:19.720
Message Follows:
Space Weather Message Code: WARK04
Serial Number: 5331
Issue Time: 2026 Apr 30 2006 UTC
WARNING: Geomagnetic K-index of 4 expected
Valid From: 2026 Apr 30 2005 UTC
Valid To: 2026 May 01 0600 UTC
Warning Condition: Onset
NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation
Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.
-------------------
Product ID: TIIA
Issued: 2026-04-27 01:06:25.970
Message Follows:
Space Weather Message Code: ALTTP2
Serial Number: 1480
Issue Time: 2026 Apr 27 0106 UTC
ALERT: Type II Radio Emission
Begin Time: 2026 Apr 26 2257 UTC
Estimated Velocity: 834 km/s
Description: Type II emissions occur in association with eruptions on the sun and typically indicate a coronal mass ejection is associated with a flare event.
-------------------
Product ID: K04W
Issued: 2026-04-26 23:33:07.687
Message Follows:
Space Weather Message Code: WARK04
Serial Number: 5330
Issue Time: 2026 Apr 26 2333 UTC
EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5329
Valid From: 2026 Apr 26 0359 UTC
Now Valid Until: 2026 Apr 27 0900 UTC
Warning Condition: Persistence
NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation
Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.
-------------------
Product ID: XM5S
Issued: 2026-04-26 23:17:50.840
Message Follows:
Space Weather Message Code: SUMXM5
Serial Number: 314
Issue Time: 2026 Apr 26 2317 UTC
SUMMARY: X-ray Event exceeded M5
Begin Time: 2026 Apr 26 2251 UTC
Maximum Time: 2026 Apr 26 2257 UTC
End Time: 2026 Apr 26 2302 UTC
X-ray Class: M6.0
Location: N21W33
NOAA Scale: R2 - Moderate
NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation
Potential Impacts: Area of impact centered primarily on sub-solar point on the sunlit side of Earth.
Radio - Limited blackout of HF (high frequency) radio communication for tens of minutes.
-------------------
Product ID: BHIS
Issued: 2026-04-26 23:08:38.813
Message Follows:
Space Weather Message Code: SUM10R
Serial Number: 909
Issue Time: 2026 Apr 26 2308 UTC
SUMMARY: 10cm Radio Burst
Begin Time: 2026 Apr 26 2256 UTC
Maximum Time: 2026 Apr 26 2257 UTC
End Time: 2026 Apr 26 2258 UTC
Duration: 1 minutes
Peak Flux: 260 sfu
Latest Penticton Noon Flux: 148 sfu
Description: A 10cm radio burst indicates that the electromagnetic burst associated with a solar flare at the 10cm wavelength was double or greater than the initial 10cm radio background. This can be indicative of significant radio noise in association with a solar flare. This noise is generally short-lived but can cause interference for sensitive receivers including radar, GPS, and satellite communications.
Current 2026 May 02 1205 UTC
Solar-terrestrial indices for 01 May follow.
Solar flux 145 and estimated planetary A-index 14.
The estimated planetary K-index at 1200 UTC on 02 May was 2.00.
No space weather storms were observed for the past 24 hours.
No space weather storms are predicted for the next 24 hours.
Official Space Weather Advisory issued by NOAA Space Weather Prediction Center
Boulder, Colorado, USA
SPACE WEATHER ADVISORY OUTLOOK #26-17
2026 April 26 at 11:47 p.m. MDT (2026 April 27 0547 UTC)
**** SPACE WEATHER OUTLOOK ****
Summary For April 20-26
R1 (Minor) radio blackouts were observed on 23-26 Apr due to activity from Regions 4419. 4420, 4423, and 4425.
R2 (Moderate) radio blackouts were observed on 24 Apr and 26 Apr due to activity from Region 4419 and 4420.
R3 (Strong) radio blackouts were observed on 24 Apr due to activity from Region 4419.
G1 (Minor) geomagnetic storm levels were observed on 20-21 Apr due to influence from a coronal hole.
No other space weather storms were observed during the summary period.
Outlook For April 27-May 3
R1-R2 (Minor-Moderate) radio blackouts are likely over 27 Apr - 03 May due to the flare potential of multiple active regions.
No other space weather storms are expected during the outlook period.