Alert archive / New Jersey / Mesoscale Discussions in 2011

Mesoscale Discussion 48

January 26, 20115 states

The Storm Prediction Center issued this mesoscale discussion at Jan 26, 2011, 11:12 AM EST for 5 states. It was in force for 4 hr.

The area

The outline as issued.

The facts

Issued: Jan 26, 2011, 11:12 AM EST (16:12 UTC)
Expired: Jan 26, 2011, 3:15 PM EST
In force: 4 hr
Issued by: the Storm Prediction Center

All 27 counties

Bristol County, MA, Bergen County, NJ, Essex County, NJ, Hudson County, NJ, Hunterdon County, NJ, Mercer County, NJ, Middlesex County, NJ, Monmouth County, NJ, Morris County, NJ, Passaic County, NJ, Somerset County, NJ, Union County, NJ, Bronx County, NY, Kings County, NY, Nassau County, NY, New York County, NY, Queens County, NY, Richmond County, NY, Rockland County, NY, Suffolk County, NY, Westchester County, NY, Bucks County, PA, Montgomery County, PA, Bristol County, RI, Kent County, RI, Newport County, RI, Washington County, RI

The radar

The Brookhaven radar (KOKX), 41 km from the middle of the area, began a volume at 16:15 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

Brookhaven, NY (KOKX), launched 12:00Z, 4.2 hours before the alert went out and 41 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: 956 m above ground
0-6 km bulk shear: 63 kt
0-1 km storm-relative helicity: 44 m²/s²
0-3 km storm-relative helicity: 70 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.

740 
ACUS11 KWNS 261612
SWOMCD
SPC MCD 261612 
MAZ000-RIZ000-CTZ000-NYZ000-NJZ000-PAZ000-262015-

MESOSCALE DISCUSSION 0048
NWS STORM PREDICTION CENTER NORMAN OK
1012 AM CST WED JAN 26 2011

AREAS AFFECTED...NERN NJ/NYC METRO AREA AND LONG ISLAND/SRN AND ERN
CT/RI

CONCERNING...WINTER MIXED PRECIPITATION 

VALID 261612Z - 262015Z

ONGOING SNOWFALL WITH EMBEDDED AREAS OF HIGHER RATES FROM NERN NJ
THROUGH NEW YORK CITY METRO AREA...ACROSS LONG ISLAND TO SRN EXTENT
OF CT WILL PERSIST THROUGH 18Z.  SNOWFALL RATES /UP TO 1 IN PER HR/
WILL SPREAD NEWD ACROSS ERN CT INTO RI THROUGH EARLY AFTERNOON. 
MEANWHILE...THE NEW YORK CITY AREA SWWD INTO NERN/CENTRAL NJ MAY
TRANSITION TO A BRIEF 1-2 HOUR PERIOD OF SLEET AND/OR FREEZING RAIN
MIXED WITH LIGHT SNOW BEFORE PRECIPITATION DIMINISHES DURING THE
EARLY-MID AFTERNOON. 

AT 1545Z...REGIONAL RADAR IMAGERY SHOWED A BAND OF WINTRY
PRECIPITATION...MAINLY IN THE FORM OF SNOW...EXTENDING FROM BWI/PHL
NEWD TO NYC AREA INTO SWRN NEW ENGLAND.  ENELY SURFACE WINDS ACROSS
THIS REGION ARE EXPECTED TO MAINTAIN SUB-FREEZING TEMPERATURES. 
FORECAST SOUNDINGS SUGGEST AN INCREASE IN LOWER TROPOSPHERIC
TEMPERATURES TO ABOVE 0 C IN THE 750-850 MB LAYER FROM CENTRAL NJ TO
THE NYC AREA...RESULTING IN VERTICAL THERMAL STRUCTURE SUPPORTIVE OF
A TRANSITION TO SOME SLEET/FREEZING RAIN MIXED WITH LIGHT SNOW BY
17-18Z.  THESE THERMODYNAMIC TRENDS ARE SUPPORTED BY THE RUC AND 09Z
SREF.

FARTHER NE ACROSS SRN NEW ENGLAND...FORECAST SOUNDINGS SUGGEST THE
VERTICAL THERMAL PROFILE WILL REMAIN COLD ENOUGH FOR ALL SNOW
THROUGH MID AFTERNOON /20Z/...AND THEN A POTENTIAL FOR SLEET AND/OR
FREEZING RAIN MIXING IN WITH THE SNOW.

..PETERS.. 01/26/2011

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

ATTN...WFO...BOX...OKX...ALY...PHI...

LAT...LON   41957096 41207135 40567361 40047439 40177550 40717539
            41297384 41587337 41707285 41957096

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jan 26, 2:19 PM EST	Mesoscale Discussion	SPC	Atlantic, Burlington, Camden, Cape May, Cumberland, Essex and 12 more	6 hr
Jan 26, 7:30 AM EST	Mesoscale Discussion	SPC	Allegheny, Armstrong, Bedford, Blair, Cambria, Franklin and 7 more	5 hr

Nearby

Mesoscale Discussions in New Jersey, 2011 Mesoscale Discussions in New York, 2011 Mesoscale Discussions in Connecticut, 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.