Alert archive / New Jersey / Severe Thunderstorm Watches in 2021
Severe Thunderstorm Watch 236
The Storm Prediction Center issued this severe thunderstorm watch at Jun 4, 2021, 3:09 PM EDT for 4 states. It was in force for 5 hr.
The area
The outline as issued.
The facts
- Issued
- Jun 4, 2021, 3:09 PM EDT (19:09 UTC)
- Expired
- Jun 4, 2021, 7:48 PM EDT
- In force
- 5 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 1 in
- Strongest gust expected
- 55 kt
All 33 counties
New Castle County, DE, Atlantic County, NJ, Bergen County, NJ, Burlington County, NJ, Camden County, NJ, Cape May County, NJ, Cumberland County, NJ, Essex County, NJ, Gloucester County, NJ, Hudson County, NJ, Hunterdon County, NJ, Mercer County, NJ, Middlesex County, NJ, Monmouth County, NJ, Morris County, NJ, Ocean County, NJ, Passaic County, NJ, Salem County, NJ, Somerset County, NJ, Union County, NJ, Bronx County, NY, Kings County, NY, Nassau County, NY, New York County, NY, Queens County, NY, Richmond County, NY, Rockland County, NY, Westchester County, NY, Bucks County, PA, Chester County, PA, Delaware County, PA, Montgomery County, PA, Philadelphia County, PA
The radar
The Philadelphia radar (KDIX), 58 km from the middle of the area, began a volume at 19:11 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.
What SPC expected
The probabilities SPC published with the watch, for the watch area over its life.
- Two or more tornadoes
- 10%
- One or more EF2 to EF5 tornadoes
- 2%
- Ten or more severe wind reports
- 40%
- One or more gusts of 65 knots or more
- 5%
- Ten or more severe hail reports
- 20%
- One or more hailstones of 2 inches or more
- 5%
- Six or more combined severe hail and wind reports
- 70%
Warnings issued inside it
12 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 4, 3:10 PM EDT | Severe Thunderstorm Warning | OKX | Bergen, Essex, Hudson, Passaic, Union | 50 min |
| Jun 4, 3:14 PM EDT | Severe Thunderstorm Warning | PHI | Bucks, Montgomery, Philadelphia | 46 min |
| Jun 4, 3:18 PM EDT | Severe Thunderstorm Warning | PHI | Burlington, Mercer | 42 min |
| Jun 4, 3:23 PM EDT | Severe Thunderstorm Warning | PHI | Hunterdon, Mercer, Middlesex, Somerset | 67 min |
| Jun 4, 3:43 PM EDT | Severe Thunderstorm Warning | OKX | Bergen, Hudson | 47 min |
| Jun 4, 3:46 PM EDT | Severe Thunderstorm Warning | PHI | Burlington, Camden, Mercer | 44 min |
| Jun 4, 4:12 PM EDT | Severe Thunderstorm Warning | PHI | Burlington, Mercer, Middlesex, Monmouth, Ocean | 63 min |
| Jun 4, 4:19 PM EDT | Severe Thunderstorm Warning | OKX | Bronx, Kings, Nassau, Queens, Suffolk, Westchester | 41 min |
| Jun 4, 4:20 PM EDT | Severe Thunderstorm Warning | PHI | Burlington, Camden, Gloucester | 40 min |
| Jun 4, 4:23 PM EDT | Severe Thunderstorm Warning | PHI | Burlington, Ocean | 52 min |
| Jun 4, 5:12 PM EDT | Severe Thunderstorm Warning | PHI | Ocean | 18 min |
| Jun 4, 6:27 PM EDT | Severe Thunderstorm Warning | PHI | Atlantic, Cape May, Cumberland | 48 min |
Discussions around it
SPC mesoscale discussions over the same counties from four hours before the watch to its end.
The nearest sounding before it
Brookhaven, NY (KOKX), launched 12:00Z, 7.2 hours before the alert went out and 117 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
- 233 J/kg
- Mixed-layer CIN
- -50 J/kg
- Mixed-layer LCL
- 526 m above ground
- 0-6 km bulk shear
- 38 kt
- 0-1 km storm-relative helicity
- 30 m²/s²
- 0-3 km storm-relative helicity
- 95 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
943 WWUS20 KWNS 041904 SEL6 SPC WW 041904 CTZ000-DEZ000-NJZ000-NYZ000-PAZ000-CWZ000-050000- URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 236 NWS Storm Prediction Center Norman OK 305 PM EDT Fri Jun 4 2021 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Connecticut Delaware New Jersey Southern New York Far Eastern Pennsylvania Coastal Waters * Effective this Friday afternoon and evening from 305 PM until 800 PM EDT. * Primary threats include... Scattered damaging wind gusts to 65 mph possible Isolated large hail events to 1 inch in diameter possible SUMMARY...Clusters of storms will move east-southeastward toward New Jersey and southern New York including the New York City vicinity, with the strongest storms capable of wind damage and marginally severe hail. The severe thunderstorm watch area is approximately along and 45 statute miles east and west of a line from 35 miles northwest of Islip NY to 25 miles south southeast of Wilmington DE. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU6). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Severe Thunderstorm Watch means conditions are favorable for severe thunderstorms in and close to the watch area. Persons in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings. Severe thunderstorms can and occasionally do produce tornadoes. && OTHER WATCH INFORMATION...CONTINUE...WW 235... AVIATION...A few severe thunderstorms with hail surface and aloft to 1 inch. Extreme turbulence and surface wind gusts to 55 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 30025. ...Guyer
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 4, 2:26 PM EDT | Mesoscale Discussion | SPC | New Castle | 94 min |
| Jun 4, 4:12 PM EDT | Mesoscale Discussion | SPC | Kent, New Castle, Sussex | 93 min |
| Jun 4, 12:46 PM EDT | Mesoscale Discussion | SPC | Anne Arundel, Calvert, Charles, Prince George's, Queen Anne's, Saint Mary's and 2 more | 59 min |
| Jun 4, 12:59 PM EDT | Severe Thunderstorm Watch | SPC | Calvert, Charles, Dorchester, Saint Mary's, Somerset, Wicomico | 7 hr |
Nearby
Severe Thunderstorm Watches in New Jersey, 2021Severe Thunderstorm Watches in New York, 2021Severe Thunderstorm Watches in Pennsylvania, 2021Every severe thunderstorm watch 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.