Alert archive / New York / Mesoscale Discussions in 2021
Mesoscale Discussion 1186
The Storm Prediction Center issued this mesoscale discussion at Jul 7, 2021, 4:48 PM EDT for 5 states. It was in force for 87 min.
The area
The outline as issued.
The facts
- Issued
- Jul 7, 2021, 4:48 PM EDT (20:48 UTC)
- Expired
- Jul 7, 2021, 6:15 PM EDT
- In force
- 87 min
- Issued by
- the Storm Prediction Center
- Concerning
- Severe thunderstorm watch 344
All 77 counties
Berkshire County, MA, Bristol County, MA, Essex County, MA, Franklin County, MA, Hampden County, MA, Hampshire County, MA, Middlesex County, MA, Norfolk County, MA, Plymouth County, MA, Suffolk County, MA, Worcester County, MA, Bergen County, NJ, Essex County, NJ, Hudson County, NJ, Hunterdon County, NJ, Mercer County, NJ, Middlesex County, NJ, Monmouth County, NJ, Morris County, NJ, Passaic County, NJ, Somerset County, NJ, Sussex County, NJ, Union County, NJ, Warren County, NJ, Albany County, NY, Bronx County, NY, Broome County, NY, Chemung County, NY, Chenango County, NY, Columbia County, NY, Delaware County, NY, Dutchess County, NY, Greene County, NY, Kings County, NY, Nassau County, NY, New York County, NY, Orange County, NY, Putnam County, NY, Queens County, NY, Rensselaer County, NY, Richmond County, NY, Rockland County, NY, Schoharie County, NY, Schuyler County, NY, Steuben County, NY, Suffolk County, NY, Sullivan County, NY, Tioga County, NY, Tompkins County, NY, Ulster County, NY, Westchester County, NY, Berks County, PA, Bradford County, PA, Bucks County, PA, Carbon County, PA, Columbia County, PA, Lackawanna County, PA, Lehigh County, PA, Luzerne County, PA, Lycoming County, PA, Monroe County, PA, Montgomery County, PA, Montour County, PA, Northampton County, PA, Northumberland County, PA, Pike County, PA, Schuylkill County, PA, Sullivan County, PA, Susquehanna County, PA, Tioga County, PA, Wayne County, PA, Wyoming County, PA, Bristol County, RI, Kent County, RI, Newport County, RI, Providence County, RI, Washington County, RI
The radar
The Albany radar (KENX), 129 km from the middle of the area, began a volume at 20:50 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
Brookhaven, NY (KOKX), launched 12:00Z, 8.8 hours before the alert went out and 130 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.
- Mixed-layer CAPE
- 568 J/kg
- Mixed-layer CIN
- -83 J/kg
- Mixed-layer LCL
- 901 m above ground
- 0-6 km bulk shear
- 26 kt
- 0-1 km storm-relative helicity
- 79 m²/s²
- 0-3 km storm-relative helicity
- 109 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.3
The text
As transmitted.
198
ACUS11 KWNS 072049
SWOMCD
SPC MCD 072048
MAZ000-RIZ000-CTZ000-NYZ000-VTZ000-NJZ000-PAZ000-072215-
Mesoscale Discussion 1186
NWS Storm Prediction Center Norman OK
0348 PM CDT Wed Jul 07 2021
Areas affected...Southern NY...eastern PA...northern
NJ...CT...RI...MA
Concerning...Severe Thunderstorm Watch 344...
Valid 072048Z - 072215Z
The severe weather threat for Severe Thunderstorm Watch 344
continues.
SUMMARY...The risk for damaging winds and isolated hail continues
across the watch area, and is expected to increase in coverage over
the next few hours.
DISCUSSION...A cluster of severe thunderstorms was in progress at
2040z across southwest MA, with reports of wind damage having been
received. An isolated severe storm was also located over Essex
County in northeast MA. The downstream environment remains
moderately unstable and, with steep low-level lapse rates in place
the risk for damaging winds will continue as these storms move into
northern CT and coastal areas of northeast MA, respectively.
West of this cluster of storms, additional scattered thunderstorms
continue to develop/slowly intensify along the stationary front
across southern NY, and along a confluence zone across central
through eastern PA. This trend should continue over the next few
hours as ample instability (around 2000 J/kg) and 20-30 kts of
westerly effective shear remain in place to support organized
clusters of storms. Damaging downburst winds remain the main severe
hazard.
..Bunting.. 07/07/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...BOX...OKX...ALY...PHI...BGM...CTP...
LAT...LON 42497653 42767338 42637130 42717093 42307052 41677060
41337075 41117153 40707191 40257356 40077382 40157487
40187555 40617660 40707679 41167680 41327736 41437751
42517762 42497653SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 7, 1:50 PM EDT | Mesoscale Discussion | SPC | 115 min | |
| Jul 7, 2:41 PM EDT | Severe Thunderstorm Watch | SPC | Greater Bridgeport Planning Region, Capitol Planning Region, Northwest Hills Planning Region, Lower Connecticut River Valley Planning Region, Naugatuck Valley Planning Region, Southeastern Connecticut Planning Region and 1 more | 10 hr |
| Jul 7, 7:11 PM EDT | Mesoscale Discussion | SPC | 2 hr | |
| Jul 7, 3:31 PM EDT | Severe Thunderstorm Watch | SPC | Allegany, Cattaraugus, Chautauqua | 7 hr |
| Jul 7, 1:31 PM EDT | Severe Thunderstorm Watch | SPC | Crawford, Erie | 7 hr |
| Jul 7, 3:59 PM EDT | Mesoscale Discussion | SPC | Crawford, Erie | 91 min |
Nearby
Mesoscale Discussions in New York, 2021Mesoscale Discussions in Pennsylvania, 2021Mesoscale Discussions in New Jersey, 2021Every 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.