Alert archive / New Jersey / Mesoscale Discussions in 2015

Mesoscale Discussion 813

May 27, 20157 states

The Storm Prediction Center issued this mesoscale discussion at May 27, 2015, 4:49 PM EDT for 7 states. It was in force for 86 min.

The area

The outline as issued.

The facts

Issued
May 27, 2015, 4:49 PM EDT (20:49 UTC)
Expired
May 27, 2015, 6:15 PM EDT
In force
86 min
Issued by
the Storm Prediction Center
All 63 counties

Berkshire County, MA, Franklin County, MA, Hampden County, MA, Hampshire County, MA, Franklin County, ME, Oxford County, ME, Belknap County, NH, Carroll County, NH, Cheshire County, NH, Coos County, NH, Grafton County, NH, Merrimack County, NH, Sullivan County, NH, Bergen County, NJ, Burlington County, NJ, Camden County, NJ, Essex County, NJ, Gloucester County, NJ, Hudson County, NJ, Hunterdon County, NJ, Mercer County, NJ, Middlesex County, NJ, Monmouth County, NJ, Morris County, NJ, Ocean County, NJ, Passaic County, NJ, Somerset County, NJ, Sussex County, NJ, Union County, NJ, Warren County, NJ, Albany County, NY, Bronx County, NY, Columbia County, NY, Dutchess County, NY, Greene County, NY, Kings County, NY, New York County, NY, Orange County, NY, Putnam County, NY, Queens County, NY, Rensselaer County, NY, Richmond County, NY, Rockland County, NY, Sullivan County, NY, Ulster County, NY, Washington County, NY, Westchester County, NY, Bucks County, PA, Chester County, PA, Delaware County, PA, Lehigh County, PA, Monroe County, PA, Montgomery County, PA, Northampton County, PA, Philadelphia County, PA, Pike County, PA, Bennington County, VT, Caledonia County, VT, Essex County, VT, Orange County, VT, Rutland County, VT, Windham County, VT, Windsor County, VT

The radar

The Albany radar (KENX), 97 km from the middle of the area, began a volume at 20:53 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 watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

The nearest sounding before it

Albany, NY (KALY), launched 12:00Z, 8.8 hours before the alert went out and 95 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 12:00Z on 2015-05-27Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 101 joules per kilogram.LCLLFCEL10008507005003002001001 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 12:00Z on 2015-05-27The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 188 square meters per square second.193958Sfc1 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
101 J/kg
Mixed-layer CIN
-166 J/kg
Mixed-layer LCL
994 m above ground
0-6 km bulk shear
32 kt
0-1 km storm-relative helicity
188 m²/s²
0-3 km storm-relative helicity
193 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.

667 
ACUS11 KWNS 272050
SWOMCD
SPC MCD 272049 
MEZ000-NHZ000-VTZ000-MAZ000-CTZ000-NYZ000-NJZ000-PAZ000-DEZ000-MDZ000-272215-

MESOSCALE DISCUSSION 0813
NWS STORM PREDICTION CENTER NORMAN OK
0349 PM CDT WED MAY 27 2015

AREAS AFFECTED...FROM WRN ME SSWWD TO NJ/ERN PA

CONCERNING...SEVERE THUNDERSTORM WATCH 227...

VALID 272049Z - 272215Z

THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 227
CONTINUES.

SUMMARY...RISK FOR ISOLATED DAMAGING WIND GUSTS CONTINUES.

DISCUSSION...LATEST RADAR LOOP SHOWS SOME UPTICK IN CONVECTIVE
INTENSITY ACROSS PARTICULARLY NRN PORTIONS OF THE WW AREA.  AIRMASS
DOWNSTREAM REMAINS SUFFICIENTLY UNSTABLE TO SUPPORT CONVECTIVE
MAINTENANCE...AND SHEAR LIKEWISE SUPPORTS CONTINUED SEVERE RISK. 
WITH A VERY WARM AIRMASS INDICATED E OF THE WW...WITH DEWPOINT
DEPRESSIONS SUPPORTIVE OF SOME ENHANCEMENT TO DOWNDRAFTS/OUTFLOW
WINDS...NEW WW MAY BE REQUIRED DOWNSTREAM.

..GOSS.. 05/27/2015

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

ATTN...WFO...GYX...BOX...BTV...OKX...ALY...PHI...BGM...CTP...

LAT...LON   39637409 39507483 39767604 41507513 42177433 43007394
            45277126 45307015 44606996 42577217 41767243 40767376
            39637409

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 27, 12:54 PM EDTSevere Thunderstorm WatchSPCGreater Bridgeport Planning Region, Northwest Hills Planning Region6 hr
May 27, 2:59 PM EDTMesoscale DiscussionSPC2 hr
May 27, 5:02 PM EDTSevere Thunderstorm WatchSPCCapitol Planning Region, Northeastern Connecticut Planning Region4 hr
May 27, 7:21 PM EDTMesoscale DiscussionSPC54 min
May 27, 6:17 PM EDTMesoscale DiscussionSPCAroostook, Penobscot, Piscataquis58 min
May 27, 11:50 AM EDTMesoscale DiscussionSPCBerkshire85 min
May 27, 12:21 PM EDTMesoscale DiscussionSPCBergen, Camden, Essex, Gloucester, Hunterdon, Mercer and 8 more54 min

Nearby

Mesoscale Discussions in New Jersey, 2015Mesoscale Discussions in New York, 2015Mesoscale Discussions in Pennsylvania, 2015Every mesoscale discussion in 2015

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.