Alert archive / New Hampshire / Severe Thunderstorm Warnings in 1999

Severe Thunderstorm Warning 21, NWS Gray, ME

July 6, 1999Strafford County, New Hampshire

NWS Gray, ME issued this severe thunderstorm warning at Jul 6, 1999, 3:20 PM EDT for Strafford County, New Hampshire. It was in force for 45 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Jul 6, 1999, 3:20 PM EDT (19:20 UTC)
Expired
Jul 6, 1999, 4:05 PM EDT
In force
45 min
Issued by
NWS Gray, ME
Area
Whole counties

County Strafford County, NH

The radar

The Portland,ME radar (KGYX), 91 km from the middle of the area, began a volume at 19:21 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.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Jul 6, 3:00 PM EDTSevere Thunderstorm WatchSPC6 hr

The nearest sounding before it

Gray, ME (KGYX), launched 12:00Z, 7.3 hours before the alert went out and 90 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.

Skew-T log-pSkew-T log-p diagram, Gray, ME at 12:00Z on 1999-07-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Gray, ME at 12:00Z on 1999-07-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 291 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
711 m above ground
0-6 km bulk shear
39 kt
0-1 km storm-relative helicity
291 m²/s²
0-3 km storm-relative helicity
406 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

The office that day

Everything else NWS Gray, ME issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 6, 2:31 PM EDTSevere Thunderstorm WarningGYXOxford44 min
Jul 6, 4:54 PM EDTSevere Thunderstorm WarningGYXYork61 min
Jul 6, 1:08 AM EDTSevere Thunderstorm WarningGYXCarroll42 min
Jul 6, 2:05 PM EDTSevere Thunderstorm WarningGYXCoos60 min
Jul 6, 3:41 PM EDTSevere Thunderstorm WarningGYXGrafton, Sullivan49 min
Jul 6, 3:58 PM EDTSevere Thunderstorm WarningGYXBelknap, Merrimack77 min
Jul 6, 3:58 PM EDTSevere Thunderstorm WarningGYXCarroll77 min
Jul 6, 4:43 PM EDTSevere Thunderstorm WarningGYXRockingham, Strafford47 min

Nearby

Severe Thunderstorm Warnings in New Hampshire, 1999Every severe thunderstorm warning in 1999

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.