地磁気活動

今日は磁気嵐が起きている?Kp 指数は地球全体の磁場の乱れを示します。オーロラが見えるかは場所、暗さ、天気にも左右されます。

G0

磁気嵐

基準未満
観測 · NOAA
S0

太陽放射線嵐

基準未満
観測 · NOAA
R0

電波障害

基準未満
観測 · NOAA
太陽風速度
532.49 km/s観測
陽子密度
1.87 p/cm³観測
Bt:
4.97 nT観測
Bz:
-3.38 nT観測
地磁気活動 · Kp
4.67 Kp観測
Dst 指数
-48.00 nTデータ遅延

地磁気活動 · Kp

4.67
観測

Kp は 0~9 で、5 から磁気嵐の基準に達します。地球全体の指標であり、各都市でオーロラが見える確率ではありません。

更新時刻 · 2026年11月1日 00:00 UTCNOAA SWPC

Dst 指数

-48 nT
観測
データ遅延 · 2026年11月1日 03:00 UTCNOAA SWPC

南北半球のオーロラ出力

49 GW
予報
北向き南向き
更新時刻 · 2026年11月1日 04:40 UTCNOAA SWPC

北半球オーロラ予報図

北半球オーロラ予報図
NOAA SWPC / OVATION

南半球オーロラ予報図

南半球オーロラ予報図
NOAA SWPC / OVATION
専門データ・公報原文

GOES · 磁力計

42.7 nT
観測
HpHeHn
更新時刻 · 2026年11月1日 04:37 UTCNOAA SWPC

磁力計

磁力計
Natural Resources Canada
予報・警報 · 公式公報・英語原文
ALERT: Geomagnetic K-index of 5
Space Weather Message Code: ALTK05
Serial Number: 2060
Issue Time: 2026 Nov 01 0117 UTC

ALERT: Geomagnetic K-index of 5 
Threshold Reached: 2026 Nov 01 0117 UTC
Synoptic Period: 0000-0300
Active Warning: YES
Noaa Scale: G1 - Minor
Comment: 

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.
WARNING: Geomagnetic K-index of 5 expected
Space Weather Message Code: WARK05
Serial Number: 2274
Issue Time: 2026 Nov 01 0008 UTC

WARNING: Geomagnetic K-index of 5 expected 
Valid From: 2026 Nov 01 0007 UTC
Valid To: 2026 Nov 01 0900 UTC
Warning Conditions: Persistence
Noaa Scale: G1 - Minor
Comment: Re-issued due to technical issues with end date of previous warning.


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.
ALERT: Geomagnetic K-index of 6
Space Weather Message Code: ALTK06
Serial Number: 729
Issue Time: 2026 Oct 31 1914 UTC

ALERT: Geomagnetic K-index of 6 
Threshold Reached: 2026 Oct 31 1914 UTC
Synoptic Period: 1800-2100
Active Warning: YES
Noaa Scale: G2 - Moderate
Comment: 

NOAA Scale: G2 - Moderate

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 55 degrees Geomagnetic Latitude.
Induced Currents - Power grid fluctuations can occur. High-latitude power systems may experience voltage alarms.
Spacecraft - Satellite orientation irregularities may occur; increased drag on low Earth-orbit satellites is possible.
Radio - HF (high frequency) radio propagation can fade at higher latitudes.
Aurora - Aurora may be seen as low as New York to Wisconsin to Washington state.
WARNING: Geomagnetic K-index of 6 expected
Space Weather Message Code: WARK06
Serial Number: 673
Issue Time: 2026 Oct 31 1908 UTC

WARNING: Geomagnetic K-index of 6 expected 
Valid From: 2026 Oct 31 1908 UTC
Valid To: 2026 Oct 31 2359 UTC
Warning Conditions: Onset
Noaa Scale: G2 - Moderate
Comment: 

NOAA Scale: G2 - Moderate

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 55 degrees Geomagnetic Latitude.
Induced Currents - Power grid fluctuations can occur. High-latitude power systems may experience voltage alarms.
Spacecraft - Satellite orientation irregularities may occur; increased drag on low Earth-orbit satellites is possible.
Radio - HF (high frequency) radio propagation can fade at higher latitudes.
Aurora - Aurora may be seen as low as New York to Wisconsin to Washington state.
ALERT: Geomagnetic K-index of 5
Space Weather Message Code: ALTK05
Serial Number: 2059
Issue Time: 2026 Oct 31 1907 UTC

ALERT: Geomagnetic K-index of 5 
Threshold Reached: 2026 Oct 31 1907 UTC
Synoptic Period: 1800-2100
Active Warning: YES
Noaa Scale: G1 - Minor
Comment: 

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.
WARNING: Geomagnetic K-index of 5 expected
Space Weather Message Code: WARK05
Serial Number: 2273
Issue Time: 2026 Oct 31 1904 UTC

WARNING: Geomagnetic K-index of 5 expected 
Valid From: 2026 Oct 31 1901 UTC
Valid To: 2026 Oct 31 2359 UTC
Warning Conditions: Onset
Noaa Scale: G1 - Minor
Comment: 

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.
ALERT: Geomagnetic K-index of 4
Space Weather Message Code: ALTK04
Serial Number: 2696
Issue Time: 2026 Oct 31 1847 UTC

ALERT: Geomagnetic K-index of 4 
Threshold Reached: 2026 Oct 31 1845 UTC
Synoptic Period: 1800-2100
Active Warning: YES
Comment: 

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.
WARNING: Geomagnetic K-index of 4 expected
Space Weather Message Code: WARK04
Serial Number: 5445
Issue Time: 2026 Oct 31 1220 UTC

WARNING: Geomagnetic K-index of 4 expected 
Valid From: 2026 Oct 31 1235 UTC
Valid To: 2026 Nov 01 1500 UTC
Warning Conditions: Onset
Comment: 

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.
WARNING: Geomagnetic K-index of 5 expected
Space Weather Message Code: WARK05
Serial Number: 2272
Issue Time: 2026 Oct 30 2311 UTC

WARNING: Geomagnetic K-index of 5 expected 
Valid From: 2026 Oct 30 2310 UTC
Valid To: 2026 Oct 31 0600 UTC
Warning Conditions: Onset
Noaa Scale: G1 - Minor
Comment: 

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.
ALERT: Geomagnetic K-index of 4
Space Weather Message Code: ALTK04
Serial Number: 2695
Issue Time: 2026 Oct 30 2240 UTC

ALERT: Geomagnetic K-index of 4 
Threshold Reached: 2026 Oct 30 2235 UTC
Synoptic Period: 2100-2400
Active Warning: YES
Comment: 

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.
WARNING: Geomagnetic K-index of 4 expected
Space Weather Message Code: WARK04
Serial Number: 5444
Issue Time: 2026 Oct 30 2224 UTC

WARNING: Geomagnetic K-index of 4 expected 
Valid From: 2026 Oct 30 2223 UTC
Valid To: 2026 Oct 31 1200 UTC
Warning Conditions: Onset
Comment: 

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.
CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1,000pfu
Space Weather Message Code: ALTEF3
Serial Number: 3762
Issue Time: 2026 Oct 30 1459 UTC

CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1,000pfu
Continuation of Serial Number: 3761
Begin Time: 2026 Oct 23 1140 UTC

Yesterday Maximum 2MeV Flux: 1228 pfu
Max time: 2026 Oct 29 1630 UTC
WATCH: Geomagnetic Storm Category G1 Predicted
Space Weather Message Code: WATA20
Serial Number: 1134
Issue Time: 2026 Oct 29 1910 UTC

WATCH: Geomagnetic Storm Category G1 Predicted 
Highest Storm Level Predicted by Day:
Oct 30:  None (Below G1)   Oct 31:  G1 (Minor)   Nov 01:  G1 (Minor)   
THIS SUPERSEDES ANY/ALL PRIOR WATCHES IN EFFECT
Comment: 

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.
CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1,000pfu
Space Weather Message Code: ALTEF3
Serial Number: 3761
Issue Time: 2026 Oct 29 1614 UTC

CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1,000pfu
Continuation of Serial Number: 3760
Begin Time: 2026 Oct 23 1140 UTC

Yesterday Maximum 2MeV Flux: 2493 pfu
Max time: 2026 Oct 28 1805 UTC
WATCH: Geomagnetic Storm Category G1 Predicted
Space Weather Message Code: WATA20
Serial Number: 1133
Issue Time: 2026 Oct 28 1638 UTC

WATCH: Geomagnetic Storm Category G1 Predicted 
Highest Storm Level Predicted by Day:
Oct 29:  None (Below G1)   Oct 30:  None (Below G1)   Oct 31:  G1 (Minor)   
THIS SUPERSEDES ANY/ALL PRIOR WATCHES IN EFFECT
Comment: G1 (Minor) geomagnetic storms are likely on 31 Oct primarily due to recurrent, positive polarity coronal hole high speed stream effects.


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.
CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1,000pfu
Space Weather Message Code: ALTEF3
Serial Number: 3760
Issue Time: 2026 Oct 28 0923 UTC

CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1,000pfu
Continuation of Serial Number: 3759
Begin Time: 2026 Oct 23 1140 UTC

Yesterday Maximum 2MeV Flux: 1789 pfu
Max time: 2026 Oct 27 1715 UTC
CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1,000pfu
Space Weather Message Code: ALTEF3
Serial Number: 3759
Issue Time: 2026 Oct 27 1138 UTC

CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1,000pfu
Continuation of Serial Number: 3758
Begin Time: 2026 Oct 23 1140 UTC

Yesterday Maximum 2MeV Flux: 3304 pfu
Max time: 2026 Oct 26 1105 UTC
CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1,000pfu
Space Weather Message Code: ALTEF3
Serial Number: 3758
Issue Time: 2026 Oct 26 0517 UTC

CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1,000pfu
Continuation of Serial Number: 3757
Begin Time: 2026 Oct 23 1140 UTC

Yesterday Maximum 2MeV Flux: 2864 pfu
Max time: 2026 Oct 25 1820 UTC
CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1,000pfu
Space Weather Message Code: ALTEF3
Serial Number: 3757
Issue Time: 2026 Oct 25 0927 UTC

CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1,000pfu
Continuation of Serial Number: 3756
Begin Time: 2026 Oct 23 1140 UTC

Yesterday Maximum 2MeV Flux: 3259 pfu
Max time: 2026 Oct 24 1530 UTC
CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1,000pfu
Space Weather Message Code: ALTEF3
Serial Number: 3756
Issue Time: 2026 Oct 24 0904 UTC

CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1,000pfu
Continuation of Serial Number: 3755
Begin Time: 2026 Oct 23 1140 UTC

Yesterday Maximum 2MeV Flux: 3169 pfu
Max time: 2026 Oct 23 1540 UTC
ALERT: Geomagnetic K-index of 4
Space Weather Message Code: ALTK04
Serial Number: 2694
Issue Time: 2026 Oct 23 1955 UTC

ALERT: Geomagnetic K-index of 4 
Threshold Reached: 2026 Oct 23 1953 UTC
Synoptic Period: 1800-2100
Active Warning: YES
Comment: 

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.
WARNING: Geomagnetic K-index of 4 expected
Space Weather Message Code: WARK04
Serial Number: 5443
Issue Time: 2026 Oct 23 1927 UTC

WARNING: Geomagnetic K-index of 4 expected 
Valid From: 2026 Oct 23 1926 UTC
Valid To: 2026 Oct 24 0900 UTC
Warning Conditions: Onset
Comment: 

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.
ALERT: Electron 2MeV Integral Flux exceeded 1,000pfu
Space Weather Message Code: ALTEF3
Serial Number: 3755
Issue Time: 2026 Oct 23 1147 UTC

ALERT: Electron 2MeV Integral Flux exceeded 1,000pfu 
Threshold Reached: 2026 Oct 23 1140 UTC
Station: GOES-19
Comment: 
K04W
Space Weather Message Code: WARK04
Serial Number: 5442
Issue Time: 2026 Oct 22 2021 UTC

EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5441
Valid From: 2026 Oct 21 1616 UTC
Now Valid Until: 2026 Oct 23 0300 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.
K04W
Space Weather Message Code: WARK04
Serial Number: 5441
Issue Time: 2026 Oct 22 1648 UTC

EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5440
Valid From: 2026 Oct 21 1616 UTC
Now Valid Until: 2026 Oct 22 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.
K04W
Space Weather Message Code: WARK04
Serial Number: 5440
Issue Time: 2026 Oct 22 1424 UTC

EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5439
Valid From: 2026 Oct 21 1616 UTC
Now Valid Until: 2026 Oct 22 1800 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.
K04W
Space Weather Message Code: WARK04
Serial Number: 5439
Issue Time: 2026 Oct 22 0532 UTC

EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5438
Valid From: 2026 Oct 21 1616 UTC
Now Valid Until: 2026 Oct 22 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.
ALERT: Geomagnetic K-index of 5
Space Weather Message Code: ALTK05
Serial Number: 2058
Issue Time: 2026 Oct 22 0003 UTC

ALERT: Geomagnetic K-index of 5 
Threshold Reached: 2026 Oct 21 2359 UTC
Synoptic Period: 2100-2400
Active Warning: YES
Noaa Scale: G1 - Minor
Comment: 

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.
WARNING: Geomagnetic K-index of 5 expected
Space Weather Message Code: WARK05
Serial Number: 2271
Issue Time: 2026 Oct 21 2228 UTC

WARNING: Geomagnetic K-index of 5 expected 
Valid From: 2026 Oct 21 2227 UTC
Valid To: 2026 Oct 22 0900 UTC
Warning Conditions: Onset
Noaa Scale: G1 - Minor
Comment: 

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.
ALERT: Geomagnetic K-index of 4
Space Weather Message Code: ALTK04
Serial Number: 2693
Issue Time: 2026 Oct 21 2130 UTC

ALERT: Geomagnetic K-index of 4 
Threshold Reached: 2026 Oct 21 2059 UTC
Synoptic Period: 1800-2100
Active Warning: YES
Comment: 

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.

Kp が 5 ならオーロラが見える?

Kp 5 は G1 磁気嵐の基準ですが、見えるかは緯度、暗さ、雲にも左右されます。出発前に観測地の予報を確認しましょう。

Kp 指数は何を表す?

Kp は 0~9 で、5 から磁気嵐の基準に達します。地球全体の指標であり、各都市でオーロラが見える確率ではありません。

G・S・R の意味は?

NOAA の G は磁気嵐、S は太陽放射線嵐、R は電波障害を表し、それぞれ 1~5 の段階があります。0 は基準未満を意味し、欠測ではありません。

公開観測や予報には遅延や修正があります。オーロラの可視性や運用の安全性を保証するものではありません。重要な判断には公式情報をご確認ください。