Alert archive / Massachusetts / Mesoscale Discussions in 2016

Mesoscale Discussion 94

February 8, 201610 counties in Massachusetts; Suffolk County, New York; 5 counties in Rhode Island

The Storm Prediction Center issued this mesoscale discussion at Feb 8, 2016, 12:30 PM EST for 10 counties in Massachusetts; Suffolk County, New York; 5 counties in Rhode Island. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued: Feb 8, 2016, 12:30 PM EST (17:30 UTC)
Expired: Feb 8, 2016, 5:30 PM EST
In force: 5 hr
Issued by: the Storm Prediction Center

Counties Barnstable County, MA, Bristol County, MA, Dukes County, MA, Essex County, MA, Middlesex County, MA, Nantucket County, MA, Norfolk County, MA, Plymouth County, MA, Suffolk County, MA, Worcester County, MA, Suffolk County, NY, Bristol County, RI, Kent County, RI, Newport County, RI, Providence County, RI, Washington County, RI

The radar

The Boston radar (KBOX), 28 km from the middle of the area, began a volume at 17:31 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

Chatham, MA (KCHH), launched 12:00Z, 5.5 hours before the alert went out and 108 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: 689 m above ground
0-6 km bulk shear: 52 kt
0-1 km storm-relative helicity: 4 m²/s²
0-3 km storm-relative helicity: 122 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

094 
ACUS11 KWNS 081731
SWOMCD
SPC MCD 081730 
MAZ000-NHZ000-RIZ000-CTZ000-NYZ000-082230-

MESOSCALE DISCUSSION 0094
NWS STORM PREDICTION CENTER NORMAN OK
1130 AM CST MON FEB 08 2016

AREAS AFFECTED...PORTIONS OF ERN MA...FAR ERN NH...RI...ERN CT...AND
ERN LONG ISLAND

CONCERNING...HEAVY SNOW 

VALID 081730Z - 082230Z

SUMMARY...HEAVY SNOWFALL...WITH RATES OF 1 INCH/HR COMMON...WILL
LIKELY CONTINUE UNTIL AROUND 22Z. BLIZZARD CONDITIONS WILL REMAIN
LIKELY ACROSS SERN MA...INCLUDING THE CAPE AND ADJACENT ISLANDS.

DISCUSSION...RADAR IMAGERY AS OF 1715Z ACROSS THE REGION DEPICTS
SEVERAL BANDS OF ONGOING MODERATE TO HEAVY SNOW ASSOCIATED WITH A
STACKED UPPER/SFC LOW ESE OF THE NEW ENGLAND COAST. TENDENCY WILL BE
FOR THESE MESOSCALE BANDS TO SLOWLY SHIFT EWD TOWARDS THE COAST
THROUGH 22Z AS THE UPPER/SFC LOW CONTINUE QUICKLY NEWD AND AWAY FROM
THE MCD AREA. ACROSS WRN PORTIONS OF MA/CT...ONE OF THESE MESOSCALE
BANDS IS STRUGGLING TO PRODUCE ANY MORE THAN MODERATE SNOW PER SFC
OBSERVATIONS AND REPORTED SNOW TOTALS. THIS MAY BE DUE TO AN
INTRUSION OF DRY LOW-LEVEL AIR EVIDENT ON THE 12Z KGYX SOUNDING AND
IN RECENT SFC DEWPOINTS AOB 10 DEG F LOCATED IN THIS AREA.

FURTHER E ACROSS THE DISCUSSION AREA...SFC DEWPOINTS ARE GENERALLY
HIGHER...AND A STRONG NLY/NELY FETCH OFF THE ATLANTIC SHOULD
ENCOURAGE HIGHER SNOWFALL RATES AROUND 1 INCH/HR. A STRONG PRESSURE
GRADIENT AND NELY LOW-LEVEL JET...PARTICULARLY OVER SERN MA
INCLUDING THE CAPE/ISLANDS...WILL CONTINUE TO PROMOTE NEAR-BLIZZARD
TO BLIZZARD CONDITIONS ACROSS THIS REGION. RECENT SFC OBSERVATIONS
INDICATE REDUCTIONS IN VISIBILITY AOB 1/4 MI WITH HEAVY SNOW AND
SUSTAINED WINDS OF 20-35 KT...WITH GUSTS UP TO 45 KT AT KACK.

..GLEASON.. 02/08/2016

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

ATTN...WFO...GYX...BOX...OKX...

LAT...LON   40707292 41867240 42637167 43077081 42987055 42607052
            42077000 41666983 41196992 41197085 41027180 40817237
            40707292

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Feb 8, 6:24 AM EST	Mesoscale Discussion	SPC		6 hr

Nearby

Mesoscale Discussions in Massachusetts, 2016 Mesoscale Discussions in Rhode Island, 2016 Mesoscale Discussions in Connecticut, 2016 Every mesoscale discussion in 2016

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.