Alert archive / New Jersey / Mesoscale Discussions in 2018
Mesoscale Discussion 430
The Storm Prediction Center issued this mesoscale discussion at May 15, 2018, 3:33 PM EDT for 5 states. It was in force for 117 min.
The area
The outline as issued.
The facts
- Issued
- May 15, 2018, 3:33 PM EDT (19:33 UTC)
- Expired
- May 15, 2018, 5:30 PM EDT
- In force
- 117 min
- Issued by
- the Storm Prediction Center
All 55 counties
New Castle County, DE, Cecil County, MD, Harford County, MD, 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, Sussex County, NJ, Union County, NJ, Warren County, NJ, Bronx County, NY, Dutchess County, NY, Kings County, NY, Nassau County, NY, New York County, NY, Orange County, NY, Putnam County, NY, Queens County, NY, Richmond County, NY, Rockland County, NY, Suffolk County, NY, Westchester County, NY, Adams County, PA, Berks County, PA, Bucks County, PA, Carbon County, PA, Chester County, PA, Cumberland County, PA, Dauphin County, PA, Delaware County, PA, Lancaster County, PA, Lebanon County, PA, Lehigh County, PA, Monroe County, PA, Montgomery County, PA, Northampton County, PA, Perry County, PA, Philadelphia County, PA, Pike County, PA, Schuylkill County, PA, York County, PA
The radar
The Philadelphia radar (KDIX), 60 km from the middle of the area, began a volume at 19:35 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
Brookhaven, NY (KOKX), launched 12:00Z, 7.6 hours before the alert went out and 168 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 909 m above ground
- 0-6 km bulk shear
- 36 kt
- 0-1 km storm-relative helicity
- 107 m²/s²
- 0-3 km storm-relative helicity
- 153 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
787
ACUS11 KWNS 151933
SWOMCD
SPC MCD 151933
CTZ000-NYZ000-NJZ000-PAZ000-DEZ000-MDZ000-152130-
Mesoscale Discussion 0430
NWS Storm Prediction Center Norman OK
0233 PM CDT Tue May 15 2018
Areas affected...Eastern Pennsylvania...far southern New York...New
Jersey...northern Delaware
Concerning...Severe Thunderstorm Watch 95...
Valid 151933Z - 152130Z
The severe weather threat for Severe Thunderstorm Watch 95
continues.
SUMMARY...Damaging wind and hail are likely to progress into eastern
Pennsylvania, New Jersey, and southern New York over the next
several hours.
DISCUSSION...A line of severe storms currently stretches from
northeastern PA into south-central PA along a cold front, and
eastward near the old outflow boundary across southern NY into
western MA and CT. A very warm and moist air mass has developed
ahead of the cold front, with temperatures approaching 90 F and
dewpoints in the 68-70 F range across PA and NJ. This high theta-e
air mass combined with 7.0+ C/km midlevel lapse rates is creating a
strongly unstable environment which will support severe storms as
they continue eastward.
..Jewell.. 05/15/2018
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...BOX...OKX...ALY...PHI...BGM...CTP...LWX...
LAT...LON 40267756 40947612 41707482 41947398 41957305 41647236
41127225 40717242 40577320 40427386 39897396 39247429
38957485 39147549 39297593 39627672 39827729 40267756SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 15, 11:43 AM EDT | Mesoscale Discussion | SPC | 3 hr | |
| May 15, 1:03 PM EDT | Tornado Watch | SPC | Northwest Hills Planning Region | 4 hr |
| May 15, 1:46 PM EDT | Severe Thunderstorm Watch | SPC | Greater Bridgeport Planning Region, Lower Connecticut River Valley Planning Region, Naugatuck Valley Planning Region, Southeastern Connecticut Planning Region | 9 hr |
| May 15, 1:58 PM EDT | Mesoscale Discussion | SPC | 2 hr | |
| May 15, 2:23 PM EDT | Tornado Watch | SPC | Capitol Planning Region, Northeastern Connecticut Planning Region | 4 hr |
| May 15, 2:38 PM EDT | Mesoscale Discussion | SPC | 2 hr | |
| May 15, 5:43 PM EDT | Mesoscale Discussion | SPC | Kent | 92 min |
| May 15, 5:54 PM EDT | Severe Thunderstorm Watch | SPC | Anne Arundel, Baltimore, Carroll, Frederick, Harford, Howard and 3 more | 4 hr |
| May 15, 12:26 PM EDT | Severe Thunderstorm Watch | SPC | Chemung, Schuyler, Steuben, Tioga, Tompkins | 7 hr |
| May 15, 2:14 PM EDT | Mesoscale Discussion | SPC | Broome | 2 hr |
Nearby
Mesoscale Discussions in New Jersey, 2018Mesoscale Discussions in Pennsylvania, 2018Mesoscale Discussions in New York, 2018Every mesoscale discussion in 2018
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.