Northern lights in New Hampshire tonight
The aurora reaches New Hampshire at about Kp 6.2 in the far north of the state and Kp 6.6 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, 17:10 UTC.
The oval right now
NOAA’s OVATION model: the chance of aurora overhead 30 to 90 minutes from now, valid Sep 20, 18:08 UTC. Green is a low chance, red a high one.
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.
Open the live map with the aurora forecast
Aurora forecast from NOAA’s Space Weather Prediction Center. Original at SWPC
Tonight at Pittsburg
The most poleward town in New Hampshire 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 6.2, which is 54 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, 70% lit, and up for part of the dark hours.
Towns best placed in New Hampshire
The 24 most poleward of the 221 towns in New Hampshire with a page. Each page gives tonight’s chance there, the darkness, the moon and that town’s own cloud forecast.
- PittsburgCoos County · population 923 · 54.2° geomagneticKp 6.2
- StewartstownCoos County · population 964 · 54.2° geomagneticKp 6.2
- ColebrookCoos County · population 1,394 · 54.1° geomagneticKp 6.2
- ColumbiaCoos County · population 799 · 54.0° geomagneticKp 6.2
- StratfordCoos County · population 1,003 · 53.9° geomagneticKp 6.2
- StarkCoos County · population 550 · 53.8° geomagneticKp 6.2
- GrovetonCoos County · population 1,118 · 53.8° geomagneticKp 6.2
- MilanCoos County · population 1,418 · 53.8° geomagneticKp 6.2
- NorthumberlandCoos County · population 2,597 · 53.8° geomagneticKp 6.2
- LancasterCoos County · population 1,725 · 53.7° geomagneticKp 6.3
- BerlinCoos County · population 9,367 · 53.7° geomagneticKp 6.3
- JeffersonCoos County · population 1,071 · 53.6° geomagneticKp 6.3
- DaltonCoos County · population 987 · 53.6° geomagneticKp 6.3
- GorhamCoos County · population 1,600 · 53.6° geomagneticKp 6.3
- WhitefieldCoos County · population 1,142 · 53.6° geomagneticKp 6.3
- LittletonGrafton County · population 4,412 · 53.5° geomagneticKp 6.3
- CarrollCoos County · population 706 · 53.5° geomagneticKp 6.3
- BethlehemGrafton County · population 972 · 53.5° geomagneticKp 6.3
- MonroeGrafton County · population 808 · 53.5° geomagneticKp 6.3
- DeerfieldGrafton County · population 4,315 · 53.4° geomagneticKp 6.3
- FranconiaGrafton County · population 984 · 53.4° geomagneticKp 6.3
- Sugar HillGrafton County · population 600 · 53.4° geomagneticKp 6.3
- LisbonGrafton County · population 980 · 53.4° geomagneticKp 6.3
- BathGrafton County · population 951 · 53.4° geomagneticKp 6.3
Every town in New Hampshire with a page
221 towns at 48 degrees geomagnetic latitude or higher, which a strong storm reaches. The figure after each is the Kp it takes there.
A
- Acworth Kp 6.5
- Albany Kp 6.4
- Alexandria Kp 6.4
- Allenstown Kp 6.5
- Alstead Kp 6.5
- Alton Kp 6.5
- Amherst Kp 6.6
- Andover Kp 6.5
- Antrim Kp 6.6
- Ashland Kp 6.4
- Atkinson Kp 6.6
- Auburn Kp 6.6
B
- Barnstead Kp 6.5
- Barrington Kp 6.5
- Bath Kp 6.3
- Bedford Kp 6.6
- Belmont Kp 6.5
- Berlin Kp 6.3
- Bethlehem Kp 6.3
- Boscawen Kp 6.5
- Bow Bog Kp 6.5
- Brentwood Kp 6.6
- Bridgewater Kp 6.4
- Bristol Kp 6.4
- Brookfield Kp 6.4
- Brookline Kp 6.6
C
- Canaan Kp 6.4
- Candia Kp 6.5
- Canterbury Kp 6.5
- Carroll Kp 6.3
- Center Harbor Kp 6.4
- Center Ossipee Kp 6.4
- Charlestown Kp 6.5
- Chester Kp 6.6
- Chesterfield Kp 6.6
- Chichester Kp 6.5
- Claremont Kp 6.5
- Colebrook Kp 6.2
- Columbia Kp 6.2
- Concord Kp 6.5
- Contoocook Kp 6.5
- Conway Kp 6.4
- Croydon Kp 6.5
D
- Dalton Kp 6.3
- Danbury Kp 6.5
- Danville Kp 6.6
- Deerfield Kp 6.3
- Deering Kp 6.5
- Derry Kp 6.6
- Derry Village Kp 6.6
- Dover Kp 6.5
- Dublin Kp 6.6
- Durham Kp 6.5
E
- East Concord Kp 6.5
- East Kingston Kp 6.6
- East Merrimack Kp 6.6
- Effingham Kp 6.4
- Enfield Kp 6.4
- Epping Kp 6.6
- Epsom Kp 6.5
- Exeter Kp 6.6
F
- Farmington Kp 6.5
- Fitzwilliam Kp 6.6
- Francestown Kp 6.6
- Franconia Kp 6.3
- Franklin Kp 6.5
- Freedom Kp 6.4
- Fremont Kp 6.6
G
- Gilford Kp 6.5
- Gilmanton Kp 6.5
- Gilsum Kp 6.6
- Goffstown Kp 6.6
- Gorham Kp 6.3
- Goshen Kp 6.5
- Grafton Kp 6.4
- Grantham Kp 6.5
- Greenfield Kp 6.6
- Greenland Kp 6.6
- Greenville Kp 6.6
- Groveton Kp 6.2
H
- Hampstead Kp 6.6
- Hampton Kp 6.6
- Hampton Beach Kp 6.6
- Hampton Falls Kp 6.6
- Hanover Kp 6.4
- Harrisville Kp 6.6
- Haverhill Kp 6.4
- Henniker Kp 6.5
- Hill Kp 6.5
- Hillsborough Kp 6.5
- Hinsdale Kp 6.6
- Holderness Kp 6.4
- Hollis Kp 6.6
- Hooksett Kp 6.5
- Hopkinton Kp 6.5
- Hudson Kp 6.6
J
K
- Keene Kp 6.6
- Kensington Kp 6.6
- Kingston Kp 6.6
L
- Laconia Kp 6.5
- Lancaster Kp 6.3
- Langdon Kp 6.5
- Lebanon Kp 6.4
- Lee Kp 6.5
- Lempster Kp 6.5
- Lincoln Kp 6.4
- Lisbon Kp 6.3
- Litchfield Kp 6.6
- Littleton Kp 6.3
- Londonderry Kp 6.6
- Loudon Kp 6.5
- Lyme Kp 6.4
- Lyndeborough Kp 6.6
M
- Madbury Kp 6.5
- Madison Kp 6.4
- Manchester Kp 6.6
- Marlborough Kp 6.6
- Marlow Kp 6.5
- Mason Kp 6.6
- Meredith Kp 6.4
- Merrimack Kp 6.6
- Milan Kp 6.2
- Milford Kp 6.6
- Milton Kp 6.5
- Monroe Kp 6.3
- Mont Vernon Kp 6.6
- Moultonborough Kp 6.4
N
- Nashua Kp 6.6
- Nelson Kp 6.6
- New Boston Kp 6.6
- New Castle Kp 6.5
- New Durham Kp 6.5
- New Ipswich Kp 6.6
- New London Kp 6.5
- Newbury Kp 6.5
- Newington Kp 6.5
- Newmarket Kp 6.5
- Newport Kp 6.5
- Newton Kp 6.6
- North Conway Kp 6.4
- North Hampton Kp 6.6
- North Haverhill Kp 6.3
- North Walpole Kp 6.5
- North Woodstock Kp 6.4
- Northfield Kp 6.5
- Northumberland Kp 6.2
- Northwood Kp 6.5
- Nottingham Kp 6.5
O
P
- Pelham Kp 6.6
- Pembroke Kp 6.5
- Peterborough Kp 6.6
- Piermont Kp 6.4
- Pinardville Kp 6.6
- Pittsburg Kp 6.2
- Pittsfield Kp 6.5
- Plaistow Kp 6.6
- Plymouth Kp 6.4
- Portsmouth Kp 6.5
R
S
- Salem Kp 6.6
- Salisbury Kp 6.5
- Sanbornton Kp 6.5
- Sanbornville Kp 6.5
- Sandown Kp 6.6
- Sandwich Kp 6.4
- Seabrook Kp 6.6
- Seabrook Beach Kp 6.6
- Somersworth Kp 6.5
- South Hampton Kp 6.6
- South Hooksett Kp 6.6
- Springfield Kp 6.5
- Stark Kp 6.2
- Stewartstown Kp 6.2
- Stoddard Kp 6.5
- Strafford Kp 6.5
- Stratford Kp 6.2
- Stratham Station Kp 6.6
- Sugar Hill Kp 6.3
- Sullivan Kp 6.6
- Sunapee Kp 6.5
- Suncook Kp 6.5
- Surry Kp 6.6
- Sutton Kp 6.5
- Swanzey Kp 6.6
T
- Tamworth Kp 6.4
- Temple Kp 6.6
- Thornton Kp 6.4
- Tilton Kp 6.5
- Tilton-Northfield Kp 6.5
- Troy Kp 6.6
- Tuftonboro Kp 6.4
U
- Unity Kp 6.5
W
- Wakefield Kp 6.4
- Walpole Kp 6.5
- Warren Kp 6.4
- Washington Kp 6.5
- Waterville Valley Kp 6.4
- Weare Kp 6.5
- Webster Kp 6.5
- Wentworth Kp 6.4
- West Swanzey Kp 6.6
- Westmoreland Kp 6.6
- Whitefield Kp 6.3
- Wilmot Kp 6.5
- Wilton Kp 6.6
- Winchester Kp 6.6
- Windham Kp 6.6
- Wolfeboro Kp 6.4
- Woodstock Kp 6.4
- Woodsville Kp 6.3
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 | |
| 1.33 | 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
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, 17:10 UTC.