Northern lights in Michigan tonight
The aurora reaches Michigan at about Kp 5.8 in the far north of the state and Kp 6.9 at its southern edge. SWPC's highest forecast Kp over the next three days is 2, in the 03-06 UTC block on Mon, Sep 21. Not tonight. The forecast Kp of 2 is well below what it takes for the aurora to reach this far south.
From NOAA’s Space Weather Prediction Center, read Sep 20, 10:57 UTC.
Radar
Reflectivity now over Michigan. Open it to see the aurora forecast on the map.
Radar mosaic and map layers from NOAA MRMS. Boundaries from the Iowa Environmental Mesonet.
Rain and snow mean cloud, and cloud is the last thing between a forecast aurora and the sky you are standing under. Each town page carries that town’s own sky cover forecast for the dark hours.
Tonight at Eagle River
The most poleward town in Michigan with a page, and the first place in the state an aurora reaches. Cloud cover is on each town’s own page.
No tonight
Not tonight. The forecast Kp of 2 is well below what it takes for the aurora to reach this far south.
- The aurora reaches this place at about Kp 5.8, which is 56 degrees geomagnetic latitude on NOAA's storm scales.
- SWPC forecasts a highest Kp of 2 (2.00) during tonight's dark hours: quiet.
- The moon is waxing gibbous, 71% lit, and up for part of the dark hours.
Towns best placed in Michigan
The 24 most poleward of the 549 towns in Michigan with a page. Each page gives tonight’s chance there, the darkness, the moon and that town’s own cloud forecast.
- Eagle RiverKeweenaw County · population 71 · 56.2° geomagneticKp 5.8
- CalumetHoughton County · population 703 · 56.0° geomagneticKp 5.8
- LauriumHoughton County · population 1,941 · 56.0° geomagneticKp 5.8
- Lake LindenHoughton County · population 989 · 56.0° geomagneticKp 5.8
- HubbellHoughton County · population 946 · 56.0° geomagneticKp 5.8
- HancockHoughton County · population 4,555 · 55.9° geomagneticKp 5.8
- Dollar BayHoughton County · population 1,082 · 55.9° geomagneticKp 5.8
- HoughtonHoughton County · population 7,970 · 55.9° geomagneticKp 5.8
- Atlantic MineHoughton County · population 2,082 · 55.9° geomagneticKp 5.8
- South RangeHoughton County · population 746 · 55.8° geomagneticKp 5.8
- OntonagonOntonagon County · population 1,324 · 55.6° geomagneticKp 5.9
- BaragaBaraga County · population 1,996 · 55.6° geomagneticKp 5.9
- L'AnseBaraga County · population 1,934 · 55.5° geomagneticKp 5.9
- Sault Ste. MarieChippewa County · population 13,827 · 55.5° geomagneticKp 5.9
- Trowbridge ParkMarquette County · population 2,176 · 55.4° geomagneticKp 5.9
- MarquetteMarquette County · population 21,297 · 55.4° geomagneticKp 5.9
- HarveyMarquette County · population 1,393 · 55.3° geomagneticKp 5.9
- NegauneeMarquette County · population 4,582 · 55.3° geomagneticKp 5.9
- IshpemingMarquette County · population 6,483 · 55.3° geomagneticKp 5.9
- West IshpemingMarquette County · population 2,662 · 55.3° geomagneticKp 5.9
- MunisingAlger County · population 2,288 · 55.3° geomagneticKp 5.9
- NewberryLuce County · population 1,455 · 55.3° geomagneticKp 5.9
- RepublicMarquette County · population 570 · 55.2° geomagneticKp 6
- WakefieldGogebic County · population 1,725 · 55.2° geomagneticKp 6
Every town in Michigan with a page
549 towns at 48 degrees geomagnetic latitude or higher, which a strong storm reaches. The figure after each is the Kp it takes there.
A
- Addison Kp 6.8
- Adrian Kp 6.8
- Alanson Kp 6.1
- Albion Kp 6.8
- Algonac Kp 6.7
- Allegan Kp 6.7
- Allen Park Kp 6.7
- Allendale Kp 6.6
- Alma Kp 6.5
- Almont Kp 6.6
- Alpena Kp 6.2
- Ann Arbor Kp 6.7
- Argentine Kp 6.6
- Armada Kp 6.6
- Ashley Kp 6.6
- Athens Kp 6.8
- Atlanta Kp 6.2
- Atlantic Mine Kp 5.8
- Attica Kp 6.6
- Au Gres Kp 6.4
- Au Sable Kp 6.3
- Auburn Kp 6.5
- Auburn Hills Kp 6.7
- Augusta Kp 6.7
- Avoca Kp 6.6
B
- Bad Axe Kp 6.4
- Baldwin Kp 6.4
- Bancroft Kp 6.6
- Bangor Kp 6.8
- Baraga Kp 5.9
- Barnes Lake-Millers Lake Kp 6.6
- Baroda Kp 6.8
- Bath Kp 6.6
- Battle Creek Kp 6.7
- Bay City Kp 6.5
- Bay Harbor Kp 6.1
- Bay Shore Kp 6.1
- Beaverton Kp 6.4
- Beecher Kp 6.6
- Beechwood Kp 6.7
- Belding Kp 6.6
- Bellaire Kp 6.2
- Belleville Kp 6.8
- Bellevue Kp 6.7
- Belmont Kp 6.6
- Benton Harbor Kp 6.8
- Benton Heights Kp 6.8
- Berkley Kp 6.7
- Berrien Springs Kp 6.8
- Bessemer Kp 6
- Beulah Kp 6.3
- Beverly Hills Kp 6.7
- Big Rapids Kp 6.5
- Bingham Farms Kp 6.7
- Birch Run Kp 6.6
- Birmingham Kp 6.7
- Blissfield Kp 6.8
- Bloomfield Hills Kp 6.7
- Boyne City Kp 6.2
- Breckenridge Kp 6.5
- Bridgeport Kp 6.5
- Bridgman Kp 6.8
- Brighton Kp 6.7
- Britton Kp 6.8
- Bronson Kp 6.8
- Brooklyn Kp 6.8
- Brown City Kp 6.6
- Brownlee Park Kp 6.7
- Buchanan Kp 6.9
- Buckley Kp 6.3
- Buena Vista Kp 6.5
- Burr Oak Kp 6.8
- Burt Kp 6.6
- Burton Kp 6.6
- Byron Kp 6.6
- Byron Center Kp 6.7
C
- Cadillac Kp 6.4
- Caledonia Kp 6.7
- Calumet Kp 5.8
- Camden Kp 6.9
- Canadian Lakes Kp 6.5
- Canton Kp 6.7
- Capac Kp 6.6
- Carleton Kp 6.8
- Caro Kp 6.5
- Carrollton Kp 6.5
- Carson City Kp 6.6
- Carsonville Kp 6.5
- Caseville Kp 6.4
- Caspian Kp 6
- Cass City Kp 6.5
- Cassopolis Kp 6.8
- Cedar Springs Kp 6.6
- Center Line Kp 6.7
- Central Lake Kp 6.2
- Centreville Kp 6.8
- Charlevoix Kp 6.1
- Charlotte Kp 6.7
- Cheboygan Kp 6.1
- Chelsea Kp 6.7
- Chesaning Kp 6.6
- Chums Corner Kp 6.3
- Clare Kp 6.4
- Clarkston Kp 6.7
- Clawson Kp 6.7
- Climax Kp 6.8
- Clinton Kp 6.8
- Clinton Township Kp 6.7
- Clio Kp 6.6
- Coldwater Kp 6.8
- Coleman Kp 6.5
- Coloma Kp 6.8
- Colon Kp 6.8
- Columbiaville Kp 6.6
- Comstock Northwest Kp 6.7
- Comstock Park Kp 6.6
- Concord Kp 6.8
- Constantine Kp 6.8
- Coopersville Kp 6.6
- Corunna Kp 6.6
- Croswell Kp 6.5
- Crystal Falls Kp 6
- Cutlerville Kp 6.6
D
- Dansville Kp 6.7
- Davison Kp 6.6
- Dearborn Kp 6.7
- Dearborn Heights Kp 6.7
- Decatur Kp 6.8
- Deckerville Kp 6.5
- Deerfield Kp 6.8
- Delton Kp 6.7
- Detroit Kp 6.7
- Detroit Beach Kp 6.8
- DeWitt Kp 6.6
- Dexter Kp 6.7
- Dimondale Kp 6.7
- Dollar Bay Kp 5.8
- Douglas Kp 6.7
- Dowagiac Kp 6.8
- Dryden Kp 6.6
- Dundee Kp 6.8
- Durand Kp 6.6
E
- Eagle River Kp 5.8
- East Grand Rapids Kp 6.6
- East Jordan Kp 6.2
- East Lansing Kp 6.7
- East Tawas Kp 6.3
- Eastpointe Kp 6.7
- Eastwood Kp 6.8
- Eaton Rapids Kp 6.7
- Eau Claire Kp 6.8
- Ecorse Kp 6.7
- Edgemont Park Kp 6.7
- Edmore Kp 6.5
- Edwardsburg Kp 6.9
- Elk Rapids Kp 6.2
- Elkton Kp 6.4
- Elsie Kp 6.6
- Escanaba Kp 6.1
- Essexville Kp 6.5
- Evart Kp 6.4
F
- Fair Plain Kp 6.8
- Fairgrove Kp 6.5
- Farmington Kp 6.7
- Farmington Hills Kp 6.7
- Farwell Kp 6.4
- Fennville Kp 6.7
- Fenton Kp 6.6
- Ferndale Kp 6.7
- Ferrysburg Kp 6.6
- Flat Rock Kp 6.8
- Flint Kp 6.6
- Flushing Kp 6.6
- Forest Hills Kp 6.6
- Fostoria Kp 6.5
- Fowler Kp 6.6
- Fowlerville Kp 6.7
- Frankenmuth Kp 6.5
- Frankfort Kp 6.3
- Franklin Kp 6.7
- Fraser Kp 6.7
- Freeland Kp 6.5
- Fremont Kp 6.5
- Fruitport Kp 6.6
G
- Galesburg Kp 6.8
- Galien Kp 6.9
- Garden City Kp 6.7
- Gaylord Kp 6.2
- Gibraltar Kp 6.8
- Gladstone Kp 6.1
- Gladwin Kp 6.4
- Gobles Kp 6.7
- Goodrich Kp 6.6
- Grand Blanc Kp 6.6
- Grand Haven Kp 6.6
- Grand Ledge Kp 6.7
- Grand Rapids Kp 6.6
- Grandville Kp 6.6
- Grant Kp 6.5
- Grass Lake Kp 6.8
- Grawn Kp 6.3
- Grayling Kp 6.3
- Greenville Kp 6.6
- Greilickville Kp 6.3
- Grosse Ile Kp 6.8
- Grosse Pointe Kp 6.7
- Grosse Pointe Farms Kp 6.7
- Grosse Pointe Park Kp 6.7
- Grosse Pointe Shores Kp 6.7
- Grosse Pointe Woods Kp 6.7
- Gwinn Kp 6
H
- Hamtramck Kp 6.7
- Hancock Kp 5.8
- Harbor Beach Kp 6.4
- Harbor Springs Kp 6.1
- Harper Woods Kp 6.7
- Harrison Kp 6.4
- Harrisville Kp 6.3
- Hart Kp 6.5
- Hartford Kp 6.8
- Harvey Kp 5.9
- Haslett Kp 6.7
- Hastings Kp 6.7
- Hazel Park Kp 6.7
- Hemlock Kp 6.5
- Hesperia Kp 6.5
- Highland Park Kp 6.7
- Hillman Kp 6.2
- Hillsdale Kp 6.8
- Holland Kp 6.7
- Holly Kp 6.6
- Holt Kp 6.7
- Homer Kp 6.8
- Hopkins Kp 6.7
- Horton Bay Kp 6.2
- Houghton Kp 5.8
- Houghton Lake Kp 6.3
- Howard City Kp 6.5
- Howell Kp 6.7
- Hubbard Lake Kp 6.2
- Hubbell Kp 5.8
- Hudson Kp 6.8
- Hudsonville Kp 6.6
- Huntington Woods Kp 6.7
I
- Imlay City Kp 6.6
- Indian River Kp 6.1
- Inkster Kp 6.7
- Interlochen Kp 6.3
- Ionia Kp 6.6
- Iron Mountain Kp 6.1
- Iron River Kp 6
- Ironwood Kp 6
- Ishpeming Kp 5.9
- Ithaca Kp 6.5
J
- Jackson Kp 6.8
- Jenison Kp 6.6
- Jonesville Kp 6.8
K
- K. I. Sawyer Air Force Base Kp 6
- Kalamazoo Kp 6.8
- Kalkaska Kp 6.3
- Keego Harbor Kp 6.7
- Kent City Kp 6.6
- Kentwood Kp 6.6
- Kilmanagh Kp 6.4
- Kingsford Kp 6.1
- Kingsley Kp 6.3
L
- L'Anse Kp 5.9
- Laingsburg Kp 6.6
- Lake City Kp 6.3
- Lake Fenton Kp 6.6
- Lake Isabella Kp 6.5
- Lake Linden Kp 5.8
- Lake Michigan Beach Kp 6.8
- Lake Odessa Kp 6.7
- Lake Orion Kp 6.6
- Lakeview Kp 6.5
- Lakeview Kp 6.8
- Lakewood Club Kp 6.5
- Lambertville Kp 6.8
- Lansing Kp 6.7
- Lapeer Kp 6.6
- Lathrup Village Kp 6.7
- Laurium Kp 5.8
- Lawrence Kp 6.8
- Lawton Kp 6.8
- Leland Kp 6.2
- Lennon Kp 6.6
- Leslie Kp 6.7
- Level Park-Oak Park Kp 6.7
- Lewiston Kp 6.2
- Lexington Kp 6.5
- Lincoln Park Kp 6.7
- Linden Kp 6.6
- Litchfield Kp 6.8
- Livonia Kp 6.7
- Lowell Kp 6.6
- Ludington Kp 6.4
- Luna Pier Kp 6.8
- Lyons Kp 6.6
M
- Mackinaw City Kp 6.1
- Madison Heights Kp 6.7
- Mancelona Kp 6.2
- Manchester Kp 6.8
- Manistee Kp 6.4
- Manistique Kp 6
- Manitou Beach-Devils Lake Kp 6.8
- Manton Kp 6.3
- Maple Rapids Kp 6.6
- Marcellus Kp 6.8
- Marine City Kp 6.6
- Marion Kp 6.4
- Marlette Kp 6.5
- Marquette Kp 5.9
- Marshall Kp 6.8
- Marysville Kp 6.6
- Mason Kp 6.7
- Mattawan Kp 6.8
- Maybee Kp 6.8
- Mayville Kp 6.5
- McBain Kp 6.4
- Melvindale Kp 6.7
- Memphis Kp 6.6
- Mendon Kp 6.8
- Menominee Kp 6.2
- Merrill Kp 6.5
- Metamora Kp 6.6
- Michigan Center Kp 6.8
- Middletown Kp 6.6
- Middleville Kp 6.7
- Midland Kp 6.5
- Milan Kp 6.8
- Milford Kp 6.7
- Millington Kp 6.5
- Mio Kp 6.3
- Monroe Kp 6.8
- Montague Kp 6.5
- Montrose Kp 6.6
- Morenci Kp 6.9
- Morrice Kp 6.6
- Mount Clemens Kp 6.7
- Mount Morris Kp 6.6
- Mount Pleasant Kp 6.5
- Muir Kp 6.6
- Mulliken Kp 6.7
- Munising Kp 5.9
- Muskegon Kp 6.6
- Muskegon Heights Kp 6.6
N
- Napoleon Kp 6.8
- Nashville Kp 6.7
- Negaunee Kp 5.9
- New Baltimore Kp 6.7
- New Buffalo Kp 6.9
- New Haven Kp 6.6
- New Haven Kp 6.6
- New Lothrop Kp 6.6
- Newaygo Kp 6.5
- Newberry Kp 5.9
- Niles Kp 6.9
- North Branch Kp 6.6
- North Muskegon Kp 6.6
- Northport Kp 6.2
- Northview Kp 6.6
- Northville Kp 6.7
- Norton Shores Kp 6.6
- Norway Kp 6.1
- Novi Kp 6.7
O
- Oak Hill Kp 6.4
- Oak Park Kp 6.7
- Okemos Kp 6.7
- Olivet Kp 6.7
- Onaway Kp 6.1
- Onsted Kp 6.8
- Ontonagon Kp 5.9
- Orchard Lake Kp 6.7
- Ortonville Kp 6.6
- Oscoda Kp 6.3
- Ossineke Kp 6.2
- Otisville Kp 6.6
- Otsego Kp 6.7
- Ovid Kp 6.6
- Owosso Kp 6.6
- Oxford Kp 6.6
P
- Parchment Kp 6.7
- Parkdale Kp 6.4
- Parma Kp 6.8
- Paw Paw Kp 6.8
- Paw Paw Lake Kp 6.8
- Pearl Beach Kp 6.7
- Peck Kp 6.5
- Pellston Kp 6.1
- Pentwater Kp 6.5
- Perry Kp 6.6
- Petersburg Kp 6.8
- Petoskey Kp 6.1
- Pigeon Kp 6.4
- Pinckney Kp 6.7
- Pinconning Kp 6.4
- Plainwell Kp 6.7
- Pleasant Ridge Kp 6.7
- Plymouth Kp 6.7
- Pontiac Kp 6.7
- Port Austin Kp 6.4
- Port Huron Kp 6.6
- Port Sanilac Kp 6.5
- Portage Kp 6.8
- Portland Kp 6.6
- Potterville Kp 6.7
- Prudenville Kp 6.3
Q
R
- Rapid City Kp 6.2
- Ravenna Kp 6.6
- Reading Kp 6.8
- Redford Kp 6.7
- Reed City Kp 6.4
- Reese Kp 6.5
- Republic Kp 6
- Richland Kp 6.7
- Richmond Kp 6.6
- River Rouge Kp 6.7
- Riverview Kp 6.8
- Robin Glen-Indiantown Kp 6.5
- Rochester Kp 6.7
- Rochester Hills Kp 6.7
- Rockford Kp 6.6
- Rockwood Kp 6.8
- Rogers City Kp 6.1
- Romeo Kp 6.6
- Romulus Kp 6.8
- Roosevelt Park Kp 6.6
- Roscommon Kp 6.3
- Rose City Kp 6.3
- Roseville Kp 6.7
- Royal Oak Kp 6.7
S
- Saginaw Kp 6.5
- Saginaw Township North Kp 6.5
- Saint Charles Kp 6.5
- Saint Clair Kp 6.6
- Saint Clair Shores Kp 6.7
- Saint Helen Kp 6.3
- Saint Ignace Kp 6
- Saint Johns Kp 6.6
- Saint Joseph Kp 6.8
- Saint Louis Kp 6.5
- Saline Kp 6.8
- Sand Lake Kp 6.3
- Sand Lake Kp 6.6
- Sandusky Kp 6.5
- Sanford Kp 6.5
- Saranac Kp 6.6
- Saugatuck Kp 6.7
- Sault Ste. Marie Kp 5.9
- Schoolcraft Kp 6.8
- Scottville Kp 6.4
- Sebewaing Kp 6.5
- Shelby Kp 6.5
- Shelby Kp 6.7
- Shepherd Kp 6.5
- Sheridan Kp 6.6
- Shields Kp 6.5
- Shoreham Kp 6.8
- Shorewood-Tower Hills-Harbert Kp 6.8
- Skidway Lake Kp 6.4
- South Boardman Kp 6.3
- South Gull Lake Kp 6.7
- South Haven Kp 6.7
- South Lyon Kp 6.7
- South Monroe Kp 6.8
- South Range Kp 5.8
- South Rockwood Kp 6.8
- Southfield Kp 6.7
- Southgate Kp 6.8
- Sparta Kp 6.6
- Spring Arbor Kp 6.8
- Spring Lake Kp 6.6
- Springfield Kp 6.7
- Springport Kp 6.7
- Stambaugh, Iron River Kp 6
- Standish Kp 6.4
- Stanton Kp 6.6
- Stephenson Kp 6.2
- Sterling Kp 6.4
- Sterling Heights Kp 6.7
- Stevensville Kp 6.8
- Stockbridge Kp 6.7
- Stony Point Kp 6.7
- Stony Point Kp 6.8
- Sturgis Kp 6.9
- Sunfield Kp 6.7
- Suttons Bay Kp 6.2
- Swartz Creek Kp 6.6
- Sylvan Lake Kp 6.7
T
- Tawas City Kp 6.3
- Taylor Kp 6.7
- Tecumseh Kp 6.8
- Tekonsha Kp 6.8
- Temperance Kp 6.8
- Three Oaks Kp 6.9
- Three Rivers Kp 6.8
- Traverse City Kp 6.3
- Trenton Kp 6.8
- Trowbridge Park Kp 5.9
- Troy Kp 6.7
- Twin Lake Kp 6.5
U
- Ubly Kp 6.5
- Union City Kp 6.8
- Utica Kp 6.7
V
- Vanderbilt Kp 6.2
- Vandercook Lake Kp 6.8
- Vassar Kp 6.5
- Vermontville Kp 6.7
- Vernon Kp 6.6
- Vicksburg Kp 6.8
W
- Wacousta Kp 6.6
- Wakefield Kp 6
- Waldron Kp 6.9
- Walker Kp 6.6
- Walled Lake Kp 6.7
- Warren Kp 6.7
- Waterford Kp 6.7
- Watervliet Kp 6.8
- Waverly Kp 6.7
- Wayland Kp 6.7
- Wayne Kp 6.7
- Webberville Kp 6.7
- Weidman Kp 6.5
- West Bloomfield Township Kp 6.7
- West Branch Kp 6.3
- West Ishpeming Kp 5.9
- West Monroe Kp 6.8
- Westland Kp 6.7
- Westphalia Kp 6.6
- Westwood Kp 6.8
- White Cloud Kp 6.5
- White Pigeon Kp 6.9
- Whitehall Kp 6.5
- Whitmore Lake Kp 6.7
- Williamston Kp 6.7
- Wixom Kp 6.7
- Wolf Lake Kp 6.6
- Wolverine Lake Kp 6.7
- Woodhaven Kp 6.8
- Woodland Beach Kp 6.8
- Wyandotte Kp 6.8
- Wyoming Kp 6.6
Y
Z
How far south each storm level reaches
NOAA’s space weather scales state the geomagnetic latitude each level of geomagnetic storm reaches, and the places its aurora has been seen from. The geographic latitudes are those lines converted with the geomagnetic dipole; the aurora sits low on the northern horizon there, and overhead far poleward of it.
| Storm | Geomagnetic | Central US | Eastern US | Northern Europe | NOAA says the aurora |
|---|---|---|---|---|---|
| G1 MinorKp 5 | 60° | 52°N | 51°N | 61°N | commonly visible at high latitudes: northern Michigan and Maine |
| G2 ModerateKp 6 | 55° | 47°N | 46°N | 56°N | has been seen as low as New York and Idaho |
| G3 StrongKp 7 | 50° | 42°N | 41°N | 51°N | has been seen as low as Illinois and Oregon |
| G4 SevereKp 8 | 45° | 37°N | 36°N | 45°N | has been seen as low as Alabama and northern California |
| G5 ExtremeKp 9 | 40° | 32°N | 31°N | 40°N | has been seen as low as Florida and southern Texas |
Source: NOAA space weather scales, swpc.noaa.gov/noaa-scales-explanation. Below Kp 5 the oval contracts more slowly; this section runs the line from 66 degrees geomagnetic at Kp 0 to the scale’s 60 degrees at Kp 5.
Kp by 3-hour block
SWPC’s planetary K index forecast, three days ahead. Kp is a single number for the whole planet, from magnetometers around the world, on a scale of 0 to 9 in thirds.
| Block (UTC) | Kp | Level | Seen from | Central US |
|---|---|---|---|---|
| 1.00 | Quiet | 65° geomag. | 57°N | |
| 1.00 | Quiet | 65° geomag. | 57°N | |
| 1.00 | Quiet | 65° geomag. | 57°N | |
| 1.33 | Quiet | 64° geomag. | 56°N | |
| 1.33 | Quiet | 64° geomag. | 56°N | |
| 1.67 | Quiet | 64° geomag. | 56°N | |
| 2.00 | Quiet | 64° geomag. | 55°N | |
| 1.67 | Quiet | 64° geomag. | 56°N | |
| 1.33 | Quiet | 64° geomag. | 56°N | |
| 0.67 | Quiet | 65° geomag. | 57°N | |
| 1.33 | Quiet | 64° geomag. | 56°N | |
| 1.33 | Quiet | 64° geomag. | 56°N | |
| 1.67 | Quiet | 64° geomag. | 56°N | |
| 1.67 | Quiet | 64° geomag. | 56°N | |
| 1.33 | Quiet | 64° geomag. | 56°N | |
| 1.33 | Quiet | 64° geomag. | 56°N | |
| 1.33 | Quiet | 64° geomag. | 56°N | |
| 1.33 | Quiet | 64° geomag. | 56°N | |
| 1.33 | Quiet | 64° geomag. | 56°N | |
| 1.67 | Quiet | 64° geomag. | 56°N | |
| 1.67 | Quiet | 64° geomag. | 56°N | |
| 1.67 | Quiet | 64° geomag. | 56°N |
The forecast is for the planet, not for your sky. A block at Kp 5 means the field is disturbed enough for the aurora to reach 60 degrees geomagnetic somewhere along the night side; whether you see it depends on being on the night side, on darkness, and on the clouds.
Other states with aurora pages
- Alaska
- Colorado
- Connecticut
- Delaware
- District of Columbia
- Idaho
- Illinois
- Indiana
- Iowa
- Kansas
- Kentucky
- Maine
- Maryland
- Massachusetts
- Minnesota
- Missouri
- Montana
- Nebraska
- Nevada
- New Hampshire
- New Jersey
- New York
- North Dakota
- Ohio
- Oregon
- Pennsylvania
- Rhode Island
- South Dakota
- Utah
- Vermont
- Virginia
- Washington
- West Virginia
- Wisconsin
- Wyoming
What this means
Each place is placed by its geomagnetic latitude, measured from the geomagnetic dipole pole, and compared with the reach NOAA states for each storm level on its space weather scales: G1 (Kp 5) about 60 degrees geomagnetic, G2 55, G3 50, G4 45, G5 (Kp 9) 40. Reading that backwards gives the Kp a place needs. Below Kp 5 the oval contracts more slowly and the line runs from 66 degrees at Kp 0 to 60 at Kp 5.
The forecasts have different horizons and the pages keep them apart: OVATION is the only thing that knows whether an aurora is out now, and it reaches 30 to 90 minutes ahead; the planetary Kp forecast runs three days; the 27-day outlook names likely active days and is not a forecast of any one night. None of them knows the clouds, which is why a town page reads its own forecast for those.
Sources
From NOAA’s Space Weather Prediction Center: the OVATION aurora forecast, the planetary K index forecast, the 3-day forecast, the 27-day outlook, its watches, warnings and alerts, and the real-time solar wind. Read Sep 20, 10:57 UTC.