Mesoscale Discussion 2049

Issued

Dec 18, 2021, 2:54 PM EST (19:54 UTC)

Expired

Dec 18, 2021, 8:00 PM EST

In force

5 hr

Issued by

the Storm Prediction Center

Concerning

Winter mixed precipitation

The Albany radar (KENX), 47 km from the middle of the area, began a volume at 19:53 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.

587 
ACUS11 KWNS 181954
SWOMCD
SPC MCD 181954 
MAZ000-NHZ000-CTZ000-VTZ000-NYZ000-190100-

Mesoscale Discussion 2049
NWS Storm Prediction Center Norman OK
0154 PM CST Sat Dec 18 2021

Areas affected...Parts of eastern NY...northern CT...western
MA...southern VT...and southwestern NH

Concerning...Winter mixed precipitation 

Valid 181954Z - 190100Z

SUMMARY...Winter mixed precipitation will continue across parts of
eastern NY, northern CT, and western MA before spreading northward
across southern VT and southern NH later this afternoon.

DISCUSSION...Latest radar mosaic depicts an increase in
precipitation across the Northeast this afternoon, associated with
strengthening DCVA and low/mid-level warm advection preceding an
approaching shortwave trough. The increasing warm advection aloft
continues to support partial to full melting of descending
hydrometers, where surface wet bulb temperatures remain near of just
below freezing. These factors will continue to support a mix of
freezing rain, snow, sleet, and rain through the afternoon. As
forcing for ascent continues to strengthen over the next several
hours, freezing rain rates and sleet accumulations will gradually
increase across parts of eastern NY, northern CT, and west-central
MA before spreading northward into southern VT and southern NH. The
latest high-resolution guidance suggests freezing rain rates could
approach 0.1 in/hour or greater later this afternoon into the
evening, with a focus over eastern NY and western MA. The increasing
warm advection aloft will favor a gradual transition to rain from
south to north by this evening, with moderate to heavy snow
persisting across northeastern NY, VT, NH, and southern ME into the
overnight hours.

..Weinman.. 12/18/2021

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...GYX...BOX...BTV...ALY...BGM...

LAT...LON   42457551 42897554 43447501 43417373 43307265 43007169
            42527162 42077177 41897202 41877240 41897274 41927306
            41957330 41987347 42097364 42027390 41867422 41737455
            41707475 42057521 42457551

Mesoscale Discussions in New York, 2021Mesoscale Discussions in Massachusetts, 2021Mesoscale Discussions in New Hampshire, 2021Every mesoscale discussion in 2021

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.