Alert archive / New York / Mesoscale Discussions in 2021

Mesoscale Discussion 1158

July 5, 202111 counties in New York

The Storm Prediction Center issued this mesoscale discussion at Jul 5, 2021, 9:14 PM EDT for 11 counties in New York. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: Jul 5, 2021, 9:14 PM EDT (01:14 UTC)
Expired: Jul 5, 2021, 11:15 PM EDT
In force: 2 hr
Issued by: the Storm Prediction Center
Concerning: Severe potential...watch unlikely
Chance of a watch: 5%

Counties Cayuga County, NY, Jefferson County, NY, Lewis County, NY, Monroe County, NY, Oneida County, NY, Onondaga County, NY, Ontario County, NY, Orleans County, NY, Oswego County, NY, St. Lawrence County, NY, Wayne County, NY

The radar

The Ft Drum radar (KTYX), 54 km from the middle of the area, began a volume at 01:17 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

Buffalo Intl Airport, NY (KBUF), launched 00:00Z, 1.2 hours before the alert went out and 212 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: 886 J/kg
Mixed-layer CIN: -150 J/kg
Mixed-layer LCL: 1341 m above ground
0-6 km bulk shear: 19 kt
0-1 km storm-relative helicity: 5 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.

479 
ACUS11 KWNS 060114
SWOMCD
SPC MCD 060114 
NYZ000-060315-

Mesoscale Discussion 1158
NWS Storm Prediction Center Norman OK
0814 PM CDT Mon Jul 05 2021

Areas affected...Northern New York

Concerning...Severe potential...Watch unlikely 

Valid 060114Z - 060315Z

Probability of Watch Issuance...5 percent

SUMMARY...A line of storms may produce isolated wind damaging this
evening as it moves into northern New York, though a watch is not
expected.

DISCUSSION...KTYX imagery shows a line of storms moving across Lake
Ontario towards upstate NY. Surface observations from the western
shore of Ontario reported wind gusts upwards of 25-35 mph, and
velocity data show a few pockets of stronger winds aloft within the
line. A few isolated cells developing across NY ahead of this line
suggest that the thermodynamic environment remains supportive of
convection despite the onset of diurnal cooling and increasing
low-level stability. Modest mid-level flow between 30-40 knots (as
sampled by regional VWPs) will help maintain the line at least for
another 1-2 hours amid waning instability. The general expectation
is for a few instances of damaging winds as the line moves onshore
before gradually weakening across central NY later tonight. Given
the expected weakening trend of the line, a watch is not expected.

..Moore/Hart.. 07/06/2021

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

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

LAT...LON   43417834 43867745 44407654 44737604 44997551 44847480
            44377458 43927461 43377504 43097566 42857644 42767753
            42987802 43417834

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 6, 12:33 PM EDT	Mesoscale Discussion	SPC	Albany, Bronx, Broome, Chemung, Chenango, Columbia and 26 more	2 hr
Jul 6, 1:13 PM EDT	Severe Thunderstorm Watch	SPC	Albany, Broome, Chemung, Chenango, Columbia, Cortland and 17 more	7 hr
Jul 6, 1:32 PM EDT	Severe Thunderstorm Watch	SPC	Bronx, Kings, Nassau, New York, Orange, Putnam and 5 more	8 hr
Jul 6, 4:23 PM EDT	Mesoscale Discussion	SPC	Albany, Bronx, Columbia, Delaware, Dutchess, Greene and 9 more	97 min
Jul 6, 5:25 PM EDT	Mesoscale Discussion	SPC	Bronx, Kings, Nassau, New York, Orange, Queens and 3 more	95 min

Nearby

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

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.