Alert archive / New Hampshire / Mesoscale Discussions in 2018

Mesoscale Discussion 1712

December 16, 20185 states

The Storm Prediction Center issued this mesoscale discussion at Dec 16, 2018, 9:24 PM EST for 5 states. It was in force for 4 hr.

The area

The outline as issued.

The facts

Issued
Dec 16, 2018, 9:24 PM EST (02:24 UTC)
Expired
Dec 17, 2018, 1:30 AM EST
In force
4 hr
Issued by
the Storm Prediction Center
All 21 counties

Berkshire County, MA, Franklin County, MA, Cumberland County, ME, York County, ME, Belknap County, NH, Carroll County, NH, Cheshire County, NH, Hillsborough County, NH, Merrimack County, NH, Rockingham County, NH, Strafford County, NH, Sullivan County, NH, Albany County, NY, Columbia County, NY, Rensselaer County, NY, Saratoga County, NY, Schenectady County, NY, Washington County, NY, Bennington County, VT, Windham County, VT, Windsor County, VT

The radar

The Boston radar (KBOX), 153 km from the middle of the area, began a volume at 02:25 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 nearest sounding before it

Albany, NY (KALY), launched 00:00Z, 2.4 hours before the alert went out and 137 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, Albany, NY at 00:00Z on 2018-12-17Temperature 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, Albany, NY at 00:00Z on 2018-12-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 117 square meters per square second.1939Sfc1 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
612 m above ground
0-6 km bulk shear
29 kt
0-1 km storm-relative helicity
117 m²/s²
0-3 km storm-relative helicity
233 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

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SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Dec 16, 9:36 PM ESTMesoscale DiscussionSPCCumberland, York4 hr
Dec 17, 2:03 AM ESTMesoscale DiscussionSPCAndroscoggin, Cumberland, Hancock, Kennebec, Knox, Lincoln and 5 more6 hr

Nearby

Mesoscale Discussions in New Hampshire, 2018Mesoscale Discussions in New York, 2018Mesoscale Discussions in Vermont, 2018Every mesoscale discussion in 2018

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.