Mesoscale Discussion 560

Issued

Apr 16, 2012, 1:33 PM EDT (17:33 UTC)

Expired

Apr 16, 2012, 3:00 PM EDT

In force

87 min

Issued by

the Storm Prediction Center

The Binghamton radar (KBGM), 130 km from the middle of the area, began a volume at 17:33 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.

880 
ACUS11 KWNS 161734
SWOMCD
SPC MCD 161733
NYZ000-PAZ000-161900-

MESOSCALE DISCUSSION 0560
NWS STORM PREDICTION CENTER NORMAN OK
1233 PM CDT MON APR 16 2012

AREAS AFFECTED...WRN/CNTRL NY...NWRN/N-CNTRL PA

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE

VALID 161733Z - 161900Z

ISOLATED TO SCATTERED THUNDERSTORMS MAY DEVELOP BETWEEN 1930Z AND
2100Z AND POSE A RISK FOR DMGG WIND GUSTS ACROSS WRN/CNTRL NY AND
NWRN/N-CNTRL PA. THE ISSUANCE OF A SVR TSTM WATCH IS POSSIBLE THIS
AFTERNOON.

A SFC COLD FRONT CONTINUES TRACKING EWD...AND CURRENTLY EXTENDS FROM
MIDDLE LAKE ERIE SWD ACROSS ERN OH. VISIBLE SATELLITE IMAGERY
INDICATES REGIONS OF CLEARING AMIDST A CORRIDOR OF MULTI-LAYERED
CLOUDS ACCOMPANYING THE FRONT. MOSTLY TO PARTLY SUNNY SKIES EXIST
ACROSS MUCH OF PA AND NY IN ADVANCE OF THE FRONT IN ASSOCIATION WITH
A NWD-EXTENDING ZONE OF DEEP-LAYER DRY AIR PER WATER VAPOR IMAGERY.
DIABATIC HEATING AHEAD OF THE FRONT HAS ALLOWED TEMPERATURES TO
BECOME ANOMALOUSLY WARM FOR THIS TIME OF YEAR...WITH READINGS
REACHING THE 80S IN MANY LOCATIONS. MODIFICATIONS TO THE
BUFFALO/PITTSBURGH SOUNDINGS TO ACCOUNT FOR THE LATEST SFC
OBSERVATIONS SUGGEST THAT SBCAPE VALUES ARE REACHING NEAR 500 J/KG
IN SOME LOCATIONS.

WHILE THE DEGREE OF SFC-BASED BUOYANCY IS EXPECTED TO BE LIMITED
ACROSS THE AREA OWING TO VERTICAL MIXING OF DRY AIR ALOFT INTO THE
BOUNDARY LAYER -- I.E. DEWPOINTS MAINLY IN THE LOWER/MIDDLE 50S --
STEEP LOW-LEVEL LAPSE RATES WILL LIKELY GENERATE SUFFICIENT BUOYANCY
TO SUPPORT THE DEVELOPMENT OF DEEPENING CONVECTION BY MID-AFTERNOON
GIVEN LOW-LEVEL ASCENT ALONG THE COLD FRONT AIDED BY OROGRAPHIC
EFFECTS. STORMS WILL BE MOST LIKELY OVER WRN NY ADJACENT TO LAKE
ONTARIO AND THE EAST END OF LAKE ERIE IN CLOSEST PROXIMITY TO THE
STRONGEST MID-LEVEL HEIGHT FALLS -- ON THE ORDER OF 70-100
GEOPOTENTIAL METERS PER 12 HOURS. FARTHER SOUTH INTO PA...STORM
COVERAGE IS EXPECTED TO BE RELATIVELY MORE ISOLATED OWING TO WEAKER
DEEP-LAYER FORCING FOR ASCENT.

WITH EFFECTIVE BULK SHEAR MAGNITUDES OF 50-60 KT...ORGANIZED STORM
STRUCTURES INCLUDING MULTICELLS AND BOWING LINE SEGMENTS COULD
MATERIALIZE WITH THE ATTENDANT THREAT FOR DMGG WIND GUSTS. SVR WINDS
WILL ALSO BE SUPPORTED BY THE STRONG BACKGROUND FLOW IN THE LOW
LEVELS BECOMING MANIFESTED AT THE SFC VIA DOWNWARD CONVECTIVE MASS
TRANSPORT...WITH 40-60 KT OF WSWLY FLOW IN THE 1-3-KM AGL LAYER PER
BUFFALO VWP DATA.

..COHEN.. 04/16/2012

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

ATTN...WFO...BTV...ALY...BGM...BUF...CTP...PBZ...CLE...

LAT...LON   44937461 44477450 43507487 42257601 41287758 40717937
            40957998 41557987 42667950 43337891 43567744 44107616
            44777534 44937461

Mesoscale Discussions in New York, 2012Mesoscale Discussions in Pennsylvania, 2012Every mesoscale discussion in 2012

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.