Alert archive / New Hampshire / Mesoscale Discussions in 2012

Mesoscale Discussion 826

May 16, 20125 states

The Storm Prediction Center issued this mesoscale discussion at May 16, 2012, 6:36 PM EDT for 5 states. It was in force for 84 min.

The area

The outline as issued.

The facts

Issued: May 16, 2012, 6:36 PM EDT (22:36 UTC)
Expired: May 16, 2012, 8:00 PM EDT
In force: 84 min
Issued by: the Storm Prediction Center

All 21 counties

Berkshire County, MA, Franklin County, MA, Hampden County, MA, Hampshire County, MA, Worcester County, MA, Oxford County, ME, Belknap County, NH, Carroll County, NH, Cheshire County, NH, Coos County, NH, Grafton County, NH, Hillsborough County, NH, Merrimack County, NH, Sullivan County, NH, Columbia County, NY, Rensselaer County, NY, Bennington County, VT, Essex County, VT, Orange County, VT, Windham County, VT, Windsor County, VT

The radar

The Albany radar (KENX), 145 km from the middle of the area, began a volume at 22:35 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 12:00Z, 10.6 hours before the alert went out and 123 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 304 J/kg
Mixed-layer CIN: -26 J/kg
Mixed-layer LCL: 484 m above ground
0-6 km bulk shear: 32 kt
0-1 km storm-relative helicity: 16 m²/s²
0-3 km storm-relative helicity: 56 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.1

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

578 
ACUS11 KWNS 162236
SWOMCD
SPC MCD 162236 
MEZ000-NHZ000-MAZ000-VTZ000-CTZ000-NYZ000-170000-

MESOSCALE DISCUSSION 0826
NWS STORM PREDICTION CENTER NORMAN OK
0536 PM CDT WED MAY 16 2012

AREAS AFFECTED...FAR EASTERN NY INTO PORTIONS OF VT/NH/MA/CT AND
WESTERN MAINE

CONCERNING...SEVERE THUNDERSTORM WATCH 280...

VALID 162236Z - 170000Z

THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 280
CONTINUES.

SUMMARY...SEVERE TSTM WATCH 280 CONTINUES UNTIL 01Z FOR FAR EASTERN
NY INTO PORTIONS OF VT/NH/MA/CT AND WESTERN MAINE...WITH DAMAGING
WINDS AND SEVERE HAIL THE PRIMARY CONCERNS.

DISCUSSION...SCATTERED STRONG/SEVERE TSTMS ARE ONGOING ACROSS THE
REGION THIS AFTERNOON NEAR A COLD FRONT...WITH THE MOST ROBUST
STORMS ONGOING ACROSS FAR EASTERN NY NEAR/NORTHEAST OF THE ALBANY
AREA INTO SOUTHERN VT AS OF 2230Z. THIS IS WHERE A WEAK SURFACE WAVE
/1008 MB/ IS ANALYZED ALONG THE FRONT...COINCIDENT WITH A PRE-COLD
FRONTAL AXIS OF LOWER 60S F SURFACE DEWPOINTS WITH MLCAPES ON THE
ORDER OF 500-1000 J/KG. A FEW/MAINLY TRANSIENT SUPERCELLS REMAIN
POSSIBLE IN THE SHORT TERM...BUT OTHERWISE STORMS SHOULD CONTINUE TO
GENERALLY CLUSTER/SPREAD EAST-NORTHEASTWARD ACROSS SOUTHERN VT/NH
AND WESTERN MAINE THROUGH EARLY/MID EVENING. A DOWNWARD INTENSITY
TREND SHOULD BEGIN TO OCCUR BY THE 00Z-01Z TIME FRAME AS THE
BOUNDARY LAYER COOLS...BUT NONETHELESS...ADDITIONAL PORTIONS OF
MA/NH/SOUTHWEST MAINE MAY WARRANT A SPATIAL/TEMPORAL EXTENSION OF WW
280 WHICH IS CURRENTLY SCHEDULED TO EXPIRE AT 01Z.

..GUYER.. 05/16/2012

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...GYX...BOX...BTV...ALY...

LAT...LON   43077363 44907164 45167043 43247106 42107208 41747318
            42067414 43077363

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 16, 1:18 PM EDT	Severe Thunderstorm Watch	SPC	Capitol Planning Region, Northwest Hills Planning Region	9 hr
May 16, 12:27 PM EDT	Mesoscale Discussion	SPC	Albany, Broome, Chemung, Chenango, Clinton, Columbia and 22 more	2 hr
May 16, 3:37 PM EDT	Mesoscale Discussion	SPC	Albany, Broome, Chemung, Chenango, Clinton, Columbia and 22 more	113 min

Nearby

Mesoscale Discussions in New Hampshire, 2012 Mesoscale Discussions in Massachusetts, 2012 Mesoscale Discussions in Vermont, 2012 Every mesoscale discussion in 2012

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.