Alert archive / Maine / Mesoscale Discussions in 2011

Mesoscale Discussion 83

February 2, 201115 counties in Maine; Carroll County, Coos County, New Hampshire; 7 counties in Vermont

The Storm Prediction Center issued this mesoscale discussion at Feb 2, 2011, 10:00 AM EST for 15 counties in Maine; Carroll County, Coos County, New Hampshire; 7 counties in Vermont. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued: Feb 2, 2011, 10:00 AM EST (15:00 UTC)
Expired: Feb 2, 2011, 4:00 PM EST
In force: 6 hr
Issued by: the Storm Prediction Center

All 24 counties

Androscoggin County, ME, Aroostook County, ME, Cumberland County, ME, Franklin County, ME, Hancock County, ME, Kennebec County, ME, Knox County, ME, Lincoln County, ME, Oxford County, ME, Penobscot County, ME, Piscataquis County, ME, Sagadahoc County, ME, Somerset County, ME, Waldo County, ME, Washington County, ME, Carroll County, NH, Coos County, NH, Caledonia County, VT, Chittenden County, VT, Essex County, VT, Franklin County, VT, Lamoille County, VT, Orleans County, VT, Washington County, VT

The radar

The Portland,ME radar (KGYX), 152 km from the middle of the area, began a volume at 15:00 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

Gray, ME (KGYX), launched 12:00Z, 3.0 hours before the alert went out and 152 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 564 m above ground
0-6 km bulk shear: 87 kt
0-1 km storm-relative helicity: 376 m²/s²
0-3 km storm-relative helicity: 700 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

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

702 
ACUS11 KWNS 021501
SWOMCD
SPC MCD 021500
MEZ000-NHZ000-VTZ000-022100-

MESOSCALE DISCUSSION 0083
NWS STORM PREDICTION CENTER NORMAN OK
0900 AM CST WED FEB 02 2011

AREAS AFFECTED...NRN VT...NRN NH...MUCH OF ME

CONCERNING...HEAVY SNOW

VALID 021500Z - 022100Z

BANDS OF HEAVY SNOW WILL OVERSPREAD NRN VT...NRN NH...AND MUCH OF ME
THROUGH LATE MORNING AND CONTINUE INTO THE AFTERNOON. RATES OF 1-2
INCHES PER HOUR WILL BE COMMON ACROSS THE AREA.

INTENSE ASCENT WITHIN THE DEFORMATION ZONE OF THE STRONG
EXTRATROPICAL CYCLONE OVER THE NERN CONUS WILL SUPPORT SNOWFALL
RATES OF 1 TO 2 INCHES ACROSS MUCH OF THE DISCUSSION AREA AFTER 16Z.
HOWEVER...STRONG 850-700-MB FRONTOGENESIS WILL AUGMENT THE ASCENT TO
SUPPORT A CORRIDOR OF 2-3 INCH/HOUR RATES WITHIN A 40-60-MILE WIDE
CORRIDOR CENTERED ALONG A LINE FROM 15 MILES NNW OF KBTV TO 30 MILES
NNW KEPM. IN THIS REGION...13Z RUC FORECAST SOUNDINGS INDICATE THE
ASCENT COINCIDING WITH DEEP DENDRITIC GROWTH ZONES /AOA 150 MB
THICK/ SUPPORTING VERY EFFICIENT SNOW GROWTH. ADDITIONALLY...
PRECIPITATION ACROSS SRN PORTIONS OF THE DISCUSSION AREA COULD
EXPERIENCE A CONVECTIVE ENHANCEMENT WITH THE POTENTIAL FOR AN
ISOLATED LIGHTNING STRIKE...AS MID-LEVEL LAPSE RATES STEEPEN AOA 7
C/KM PER THE RUC MODEL. THE 12Z EXPERIMENTAL HRRR INDICATES HEAVY
SNOWFALL RATES CONTINUING THROUGH MID-AFTERNOON...WITH RATES
BEGINNING TO TAPER OFF FROM WEST TO EAST FROM 20Z TO 23Z.

..COHEN/ROGERS.. 02/02/2011

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

ATTN...WFO...CAR...GYX...BTV...

LAT...LON   43986875 43757068 44137314 45247300 45317118 46177028
            46796981 46826893 46456776 45846760 44886705 44106838
            43986875

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Feb 2, 2:57 AM EST	Mesoscale Discussion	SPC	Androscoggin, Cumberland, Franklin, Kennebec, Lincoln, Oxford and 4 more	4 hr

Nearby

Mesoscale Discussions in Maine, 2011 Mesoscale Discussions in Vermont, 2011 Mesoscale Discussions in New Hampshire, 2011 Every mesoscale discussion in 2011

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.