Alert archive / New York / Mesoscale Discussions in 2012

Mesoscale Discussion 4

January 2, 20124 counties in New York

The Storm Prediction Center issued this mesoscale discussion at Jan 2, 2012, 10:13 AM EST for 4 counties in New York. It was in force for 4 hr.

The area

The outline as issued.

The facts

Issued: Jan 2, 2012, 10:13 AM EST (15:13 UTC)
Expired: Jan 2, 2012, 2:15 PM EST
In force: 4 hr
Issued by: the Storm Prediction Center

Counties Hamilton County, NY, Herkimer County, NY, Lewis County, NY, Oswego County, NY

The radar

The Ft Drum radar (KTYX), 19 km from the middle of the area, began a volume at 15:16 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

Albany, NY (KALY), launched 12:00Z, 3.2 hours before the alert went out and 191 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: 1130 m above ground
0-6 km bulk shear: 92 kt
0-1 km storm-relative helicity: -148 m²/s²
0-3 km storm-relative helicity: -92 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.

777 
ACUS11 KWNS 021513
SWOMCD
SPC MCD 021513 
NYZ000-021915-

MESOSCALE DISCUSSION 0004
NWS STORM PREDICTION CENTER NORMAN OK
0913 AM CST MON JAN 02 2012

AREAS AFFECTED...DOWNSTREAM OF LK ONTARIO

CONCERNING...HEAVY SNOW 

VALID 021513Z - 021915Z

LK EFFECT SNOW BAND IS ONGOING ACROSS PORTIONS OF UPSTATE NY...AND
WILL GRADUALLY SAG SWD LATER THIS AFTERNOON. SNOWFALL RATES NEAR 1-2
IN/HR WILL CONTINUE...WITH 3 IN/HR POSSIBLE IN ASSOCIATION WITH
THUNDERSNOW.

12Z BUF SOUNDING REFLECTS 850 MB TEMPERATURES NEAR -10 C...WHICH IN
COMBINATION WITH LAKE TEMPERATURES IN THE MID 40S F HAS LED TO STEEP
LOW-LEVEL LAPSE RATES. THESE LAPSE RATES WILL CONTINUE TO STEEPEN
THROUGH THE MORNING AS COLDER ARCTIC AIR PROGRESSES INTO NY. LONG
FETCH UNIDIRECTIONAL WLY WINDS WILL FURTHER SUPPORT A WELL-DEVELOPED
SNOW BAND THAT CURRENTLY EXTENDS TO THE NY/VT BORDER. WEAK
INSTABILITY MAY STILL LEAD TO ISOLATED LIGHTNING STRIKES...WITH
HEAVIER SNOWFALL RATES POSSIBLE IN CONVECTIVE BURSTS...WHILE TERRAIN
INDUCED HEAVIER RATES /TUG HILL PLATEAU/ REMAIN POSSIBLE AS WELL.
LOW-LEVEL WINDS WILL GRADUALLY BEGIN TO SHIFT TO A MORE WNWLY
DIRECTION AS AN UPPER TROUGH AND ASSOCIATED COLD FRONT PROGRESS
THROUGH THE AREA...LEADING TO A SWD SHIFT OF THE ONGOING SNOW BAND
LATER THIS AFTERNOON.

..HURLBUT.. 01/02/2012

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

ATTN...WFO...BTV...ALY...BGM...BUF...

LAT...LON   43907638 44167459 43867399 43477463 43277552 43177628
            43197683 43427694 43777662 43907638

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jan 2, 12:37 AM EST	Mesoscale Discussion	SPC	Cattaraugus, Chautauqua	4 hr
Jan 2, 3:50 AM EST	Mesoscale Discussion	SPC	Jefferson, Lewis	6 hr

Nearby

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

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.