| TYPE | RADIO BLACKOUT | SOLAR STORM | GEO STORM |
|---|---|---|---|
| SCALE | 1-2: 5%, 3-5: 25% | 1% | 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: 10%, 3-5: 10% | 1% | 0 |
| TEXT | None | S1 or < | none |
:Product: 3-Day Forecast
:Issued: 2025 Nov 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 5 (NOAA Scale
G1).
The greatest expected 3 hr Kp for Nov 01-Nov 03 2025 is 4.00 (below NOAA
Scale levels).
NOAA Kp index breakdown Nov 01-Nov 03 2025
Nov 01 Nov 02 Nov 03
00-03UT 4.00 3.33 2.67
03-06UT 3.33 4.00 3.67
06-09UT 3.33 3.33 3.00
09-12UT 3.00 2.67 2.67
12-15UT 3.67 2.33 2.33
15-18UT 2.67 2.00 2.33
18-21UT 2.67 2.33 2.00
21-00UT 3.33 3.33 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 Nov 01-Nov 03 2025
Nov 01 Nov 02 Nov 03
S1 or greater 1% 5% 10%
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 Nov 01-Nov 03 2025
Nov 01 Nov 02 Nov 03
R1-R2 25% 35% 45%
R3 or greater 5% 10% 10%
Rationale: There is an increasing chance for R1-R2 (Minor-Moderate)
radio blackouts all three days. A slight chance exists for R3 (Major) or
greater blackouts on 02-03 Nov.
Updated last 2025/11/01 01:40 UTC
-------------------
Product ID: TIIA
Issued: 2025-10-31 21:07:07.420
Message Follows:
Space Weather Message Code: ALTTP2
Serial Number: 1437
Issue Time: 2025 Oct 31 2107 UTC
ALERT: Type II Radio Emission
Begin Time: 2025 Oct 31 2013 UTC
Estimated Velocity: 542 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: K05W
Issued: 2025-10-31 14:27:15.627
Message Follows:
Space Weather Message Code: WARK05
Serial Number: 2128
Issue Time: 2025 Oct 31 1427 UTC
EXTENDED WARNING: Geomagnetic K-index of 5 expected
Extension to Serial Number: 2127
Valid From: 2025 Oct 29 2344 UTC
Now Valid Until: 2025 Oct 31 2100 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 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: 2025-10-31 14:27:15.597
Message Follows:
Space Weather Message Code: WARK04
Serial Number: 5128
Issue Time: 2025 Oct 31 1427 UTC
EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5127
Valid From: 2025 Oct 27 2325 UTC
Now Valid Until: 2025 Nov 01 0600 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: EF3A
Issued: 2025-10-31 13:09:59.793
Message Follows:
Space Weather Message Code: ALTEF3
Serial Number: 3551
Issue Time: 2025 Oct 31 1309 UTC
ALERT: Electron 2MeV Integral Flux exceeded 1000pfu
Threshold Reached: 2025 Oct 31 1250 UTC
Station: GOES19
Potential Impacts: Satellite systems may experience significant charging resulting in increased risk to satellite systems.
-------------------
Product ID: K05A
Issued: 2025-10-31 06:02:24.570
Message Follows:
Space Weather Message Code: ALTK05
Serial Number: 1890
Issue Time: 2025 Oct 31 0602 UTC
ALERT: Geomagnetic K-index of 5
Threshold Reached: 2025 Oct 31 0559 UTC
Synoptic Period: 0300-0600 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: 2025-10-31 05:49:16.087
Message Follows:
Space Weather Message Code: WARK04
Serial Number: 5127
Issue Time: 2025 Oct 31 0549 UTC
EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5126
Valid From: 2025 Oct 27 2325 UTC
Now Valid Until: 2025 Oct 31 2100 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: 2025-10-31 05:49:16.087
Message Follows:
Space Weather Message Code: WARK05
Serial Number: 2127
Issue Time: 2025 Oct 31 0549 UTC
EXTENDED WARNING: Geomagnetic K-index of 5 expected
Extension to Serial Number: 2126
Valid From: 2025 Oct 29 2344 UTC
Now Valid Until: 2025 Oct 31 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 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: K05W
Issued: 2025-10-30 23:52:54.940
Message Follows:
Space Weather Message Code: WARK05
Serial Number: 2126
Issue Time: 2025 Oct 30 2352 UTC
EXTENDED WARNING: Geomagnetic K-index of 5 expected
Extension to Serial Number: 2125
Valid From: 2025 Oct 29 2344 UTC
Now Valid Until: 2025 Oct 31 0600 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 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: K05A
Issued: 2025-10-30 16:50:46.740
Message Follows:
Space Weather Message Code: ALTK05
Serial Number: 1889
Issue Time: 2025 Oct 30 1650 UTC
ALERT: Geomagnetic K-index of 5
Threshold Reached: 2025 Oct 30 1645 UTC
Synoptic Period: 1500-1800 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: 2025-10-30 16:36:46.063
Message Follows:
Space Weather Message Code: WARK04
Serial Number: 5126
Issue Time: 2025 Oct 30 1636 UTC
EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5125
Valid From: 2025 Oct 27 2325 UTC
Now Valid Until: 2025 Oct 31 1200 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: 2025-10-30 14:54:43.817
Message Follows:
Space Weather Message Code: WARK05
Serial Number: 2125
Issue Time: 2025 Oct 30 1454 UTC
EXTENDED WARNING: Geomagnetic K-index of 5 expected
Extension to Serial Number: 2124
Valid From: 2025 Oct 29 2344 UTC
Now Valid Until: 2025 Oct 30 2359 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 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.
Current 2025 Oct 31 1205 UTC
Solar-terrestrial indices for 30 October follow.
Solar flux 120 and estimated planetary A-index 38.
The estimated planetary K-index at 1200 UTC on 31 October was 3.67.
Space weather for the past 24 hours has been minor.
Geomagnetic storms reaching the G1 level occurred.
Space weather for the next 24 hours is predicted to be minor.
Geomagnetic storms reaching the G1 level are expected.
Official Space Weather Advisory issued by NOAA Space Weather Prediction Center
Boulder, Colorado, USA
SPACE WEATHER ADVISORY OUTLOOK #25-39
2025 October 26 at 9:00 p.m. MDT (2025 October 27 0300 UTC)
**** SPACE WEATHER OUTLOOK ****
Summary For October 20-26
No NOAA scale geomagnetic storms were observed from 20 - 26 Oct.
A single R1 - Minor radio blackout event was observed on 20 Oct at 0527 UTC.
No S1 level events were observed from 20 - 26 Oct.
Outlook For October 27-November 2
An isolated G1/G2 storm is likely on 28 Oct - 30 Oct due to recurrent positive polarity CH HSS influence, mixed with possible weak influence from the CME that left the Sun on 23 Oct.
Possible R1/R2 radfio blackouts are possible on 31 Oct - 15 Nov due to the return of Region
4246.
Depending on the complexity of returning Region 4246, an isolated S1 solar radiation event is possible from 31 Oct - 13 Nov.