Alert archive / New York / Mesoscale Discussions in 2021
Mesoscale Discussion 1049
The Storm Prediction Center issued this mesoscale discussion at Jun 21, 2021, 3:35 PM EDT for 13 counties in New York; 11 counties in Vermont. It was in force for 85 min.
The area
The outline as issued.
The facts
- Issued
- Jun 21, 2021, 3:35 PM EDT (19:35 UTC)
- Expired
- Jun 21, 2021, 5:00 PM EDT
- In force
- 85 min
- Issued by
- the Storm Prediction Center
- Concerning
- Severe thunderstorm watch 300
All 24 counties
Clinton County, NY, Essex County, NY, Franklin County, NY, Fulton County, NY, Hamilton County, NY, Herkimer County, NY, Madison County, NY, Montgomery County, NY, Oneida County, NY, Saratoga County, NY, Schenectady County, NY, Warren County, NY, Washington County, NY, Addison County, VT, Caledonia County, VT, Chittenden County, VT, Franklin County, VT, Grand Isle County, VT, Lamoille County, VT, Orange County, VT, Orleans County, VT, Rutland County, VT, Washington County, VT, Windsor County, VT
The radar
The Burlington radar (KCXX), 97 km from the middle of the area, began a volume at 19:39 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 watches that followed
Watches SPC issued over any of the same counties within four hours of this discussion.
The nearest sounding before it
Albany, NY (KALY), launched 12:00Z, 7.6 hours before the alert went out and 116 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
- 524 J/kg
- Mixed-layer CIN
- -118 J/kg
- Mixed-layer LCL
- 990 m above ground
- 0-6 km bulk shear
- 42 kt
- 0-1 km storm-relative helicity
- 162 m²/s²
- 0-3 km storm-relative helicity
- 192 m²/s²
- Significant tornado parameter
- 0.2
- Supercell composite
- 2.4
The text
As transmitted.
650
ACUS11 KWNS 211935
SWOMCD
SPC MCD 211935
NHZ000-VTZ000-NYZ000-212100-
Mesoscale Discussion 1049
NWS Storm Prediction Center Norman OK
0235 PM CDT Mon Jun 21 2021
Areas affected...Vermont and northeast New York
Concerning...Severe Thunderstorm Watch 300...
Valid 211935Z - 212100Z
The severe weather threat for Severe Thunderstorm Watch 300
continues.
SUMMARY...The severe storm threat continues with a threat for
damaging wind and possibly some large hail.
DISCUSSION...Storm intensity has slowly increased across portions of
northern New York. This process has likely been slowed by a pocket
of drier air which advected into the region with dewpoints falling
into the mid 60s at some sites. However, low-level moisture
continues to advect northward and temperatures remain in the upper
80s to low 90s across the region with MLCAPE likely remaining in the
1500 to 2000 J/kg range into the evening.
Even showers which have developed in the region have shown rotation,
indicative of the favorable shear profile in the region. Therefore,
once stronger updrafts develop, a few intense supercells will be
possible with the threat for large hail and damaging winds. One such
storm seems to have developed just north of the Canadian border
north of the VT/NY border, possibly showing what may materialize
farther south in the next few hours.
The KCXX VWP continues to show 0-1 SRH in excess of 150 m2/s2 with
mostly southerly winds across Vermont. Therefore, if these southerly
surface winds can remain as storms develop and move into the area, a
locally higher tornado threat may materialize.
..Bentley/Hart.. 06/21/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...GYX...BTV...ALY...BGM...BUF...
LAT...LON 42857580 45017481 45137220 44697199 44157200 43467233
42807380 42657472 42857580SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 21, 11:59 AM EDT | Mesoscale Discussion | SPC | Cattaraugus, Chautauqua | 91 min |
| Jun 21, 12:31 PM EDT | Mesoscale Discussion | SPC | Clinton, Essex, Franklin, Fulton, Hamilton, Herkimer and 12 more | 89 min |
| Jun 21, 12:31 PM EDT | Severe Thunderstorm Watch | SPC | Allegany, Cattaraugus, Cayuga, Chautauqua, Erie, Genesee and 14 more | 7 hr |
| Jun 21, 1:11 PM EDT | Severe Thunderstorm Watch | SPC | Broome, Chemung, Chenango, Clinton, Cortland, Essex and 14 more | 10 hr |
| Jun 21, 3:45 PM EDT | Severe Thunderstorm Watch | SPC | Albany, Columbia, Delaware, Dutchess, Greene, Otsego and 5 more | 7 hr |
| Jun 21, 3:47 PM EDT | Mesoscale Discussion | SPC | Allegany, Livingston, Ontario, Steuben, Wayne, Yates | 58 min |
| Jun 21, 4:33 PM EDT | Severe Thunderstorm Watch | SPC | Orange | 6 hr |
| Jun 21, 6:50 PM EDT | Mesoscale Discussion | SPC | Albany, Broome, Chenango, Columbia, Cortland, Delaware and 23 more | 55 min |
Nearby
Mesoscale Discussions in New York, 2021Mesoscale Discussions in Vermont, 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.