Alert archive / New Hampshire / Tornado Watches in 2024
Tornado Watch 520
The Storm Prediction Center issued this tornado watch at Jul 10, 2024, 5:55 PM EDT for Oxford County, Maine; 4 counties in New Hampshire. It was in force for 5 hr.
The area
The outline as issued.
The facts
- Issued
- Jul 10, 2024, 5:55 PM EDT (21:55 UTC)
- Expired
- Jul 10, 2024, 10:56 PM EDT
- In force
- 5 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 1 in
- Strongest gust expected
- 60 kt
Counties Oxford County, ME, Belknap County, NH, Carroll County, NH, Coos County, NH, Grafton County, NH
The radar
The Portland,ME radar (KGYX), 114 km from the middle of the area, began a volume at 21:54 UTC, the scan nearest the moment this went out.
Open the radar archive at this moment
The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.
What SPC expected
The probabilities SPC published with the watch, for the watch area over its life.
- Two or more tornadoes
- 40%
- One or more EF2 to EF5 tornadoes
- 20%
- Ten or more severe wind reports
- 30%
- One or more gusts of 65 knots or more
- 10%
- Ten or more severe hail reports
- 5%
- One or more hailstones of 2 inches or more
- 5%
- Six or more combined severe hail and wind reports
- 50%
Warnings issued inside it
5 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 10, 6:38 PM EDT | Tornado Warning | GYX | Grafton | 37 min |
| Jul 10, 7:41 PM EDT | Flash Flood Warning | GYX | Coos, Grafton | 7 hr |
| Jul 10, 7:54 PM EDT | Severe Thunderstorm Warning | GYX | Grafton | 51 min |
| Jul 10, 8:26 PM EDT | Tornado Warning | GYX | Coos, Grafton | 24 min |
| Jul 10, 10:24 PM EDT | Flash Flood Warning | GYX | Franklin, Oxford | 6 hr |
Discussions around it
SPC mesoscale discussions over the same counties from four hours before the watch to its end.
The nearest sounding before it
Gray, ME (KGYX), launched 12:00Z, 9.9 hours before the alert went out and 113 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.
- Mixed-layer CAPE
- 227 J/kg
- Mixed-layer CIN
- -81 J/kg
- Mixed-layer LCL
- 1180 m above ground
- 0-6 km bulk shear
- 44 kt
- 0-1 km storm-relative helicity
- 83 m²/s²
- 0-3 km storm-relative helicity
- 150 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.4
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 10, 4:53 PM EDT | Mesoscale Discussion | SPC | Belknap, Carroll, Cheshire, Grafton, Merrimack, Sullivan | 97 min |
| Jul 10, 12:06 PM EDT | Tornado Watch | SPC | Addison, Caledonia, Chittenden, Essex, Franklin, Grand Isle and 6 more | 11 hr |
Nearby
Tornado Watches in New Hampshire, 2024Tornado Watches in Maine, 2024Every tornado watch in 2024
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.