Alert archive / Pennsylvania / Special Weather Statements in 2021

Special Weather Statement, NWS Philadelphia/Mount Holly

July 6, 2021Philadelphia County, Pennsylvania

NWS Philadelphia/Mount Holly issued this special weather statement at Jul 6, 2021, 10:08 PM EDT for Philadelphia County, Pennsylvania. It was in force for 37 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Jul 6, 2021, 10:08 PM EDT (02:08 UTC)
Expired
Jul 6, 2021, 10:45 PM EDT
In force
37 min
Issued by
NWS Philadelphia/Mount Holly

County Philadelphia County, PA

The radar

The Philadelphia radar (KDIX), 73 km from the middle of the area, began a volume at 02:11 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.

The nearest sounding before it

Brookhaven, NY (KOKX), launched 00:00Z, 2.1 hours before the alert went out and 221 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-pSkew-T log-p diagram, Brookhaven, NY at 00:00Z on 2021-07-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1647 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Brookhaven, NY at 00:00Z on 2021-07-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 85 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
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
1647 J/kg
Mixed-layer CIN
-86 J/kg
Mixed-layer LCL
876 m above ground
0-6 km bulk shear
25 kt
0-1 km storm-relative helicity
85 m²/s²
0-3 km storm-relative helicity
93 m²/s²
Significant tornado parameter
0.3
Supercell composite
3.3

Open this sounding in Storm Lab

The text

As transmitted.

170 
WWUS81 KPHI 070208
SPSPHI

Special Weather Statement
National Weather Service Mount Holly NJ
1008 PM EDT Tue Jul 6 2021

NJZ018-019-PAZ071-104-106-070245-
Northwestern Burlington-Camden-Lower Bucks-Eastern
Montgomery-Philadelphia-
1008 PM EDT Tue Jul 6 2021

...A STRONG THUNDERSTORM WILL AFFECT NORTHWESTERN CAMDEN...
SOUTHEASTERN MONTGOMERY...SOUTH CENTRAL BUCKS AND PHILADELPHIA
COUNTIES...

At 1008 PM EDT, a strong thunderstorm was located over Plymouth
Meeting, or 11 miles northwest of Philadelphia, moving southeast at
35 mph.

Wind gusts up to 45 mph and pea size hail are possible with this 
storm.

Locations impacted include...
Philadelphia, Camden, Gloucester City, Bensalem, Norristown,
Lansdale, West Norriton, East Norriton, Conshohocken, Palmyra,
Hatboro, Ambler, Jenkintown, Narberth, Rockledge, Abington, Bryn
Athyn, Audubon Park, Wissinoming and Feasterville-Trevose.

This includes the following highways...
 Pennsylvania Turnpike between mile markers 327 and 355.
 Northeast Extension between mile markers 21 and 27.
 Interstate 95 in Pennsylvania between mile markers 20 and 37.
 Interstate 76 in Pennsylvania between mile markers 327 and 344.
 Interstate 676 in Pennsylvania between mile markers 0 and 1.
 Interstate 676 in New Jersey between mile markers 1 and 4.
 Interstate 476 in Pennsylvania between mile markers 14 and 19.

If outdoors, consider seeking shelter inside a building.

LAT...LON 3988 7507 4003 7534 4007 7536 4006 7538
      4007 7540 4009 7541 4022 7533 4024 7530
      4013 7489
TIME...MOT...LOC 0208Z 296DEG 31KT 4013 7528 

$$

Staarmann

The office that day

Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 6, 8:03 PM EDTSpecial Weather StatementPHIBurlington, Ocean42 min
Jul 6, 8:11 PM EDTSpecial Marine WarningPHI82 min
Jul 6, 8:24 PM EDTSpecial Marine WarningPHI2 hr
Jul 6, 8:29 PM EDTSevere Thunderstorm WarningPHIHunterdon, Warren46 min
Jul 6, 8:37 PM EDTSevere Thunderstorm WarningPHIHunterdon, Middlesex, Monmouth, Morris, Somerset53 min
Jul 6, 8:50 PM EDTSevere Thunderstorm WarningPHIHunterdon, Mercer, Middlesex, Monmouth, Somerset40 min
Jul 6, 9:04 PM EDTSevere Thunderstorm WarningPHIHunterdon, Mercer, Middlesex, Somerset41 min
Jul 6, 9:10 PM EDTAreal Flood AdvisoryPHIHunterdon, Mercer, Middlesex, Monmouth, Morris, Somerset and 1 more2 hr
Jul 6, 9:29 PM EDTSevere Thunderstorm WarningPHIHunterdon, Mercer, Middlesex, Monmouth, Morris, Somerset61 min
Jul 6, 9:37 PM EDTSpecial Marine WarningPHI113 min
Jul 6, 9:48 PM EDTSevere Thunderstorm WarningPHIBurlington, Mercer, Middlesex, Monmouth, Ocean57 min
Jul 6, 10:21 PM EDTSevere Thunderstorm WarningPHIBurlington, Camden39 min
Jul 6, 10:50 PM EDTAreal Flood AdvisoryPHIMonmouth, Ocean2 hr
Jul 6, 10:54 PM EDTSpecial Weather StatementPHIBurlington51 min
Jul 6, 11:11 PM EDTSpecial Weather StatementPHIBurlington19 min
Jul 6, 11:30 PM EDTSevere Thunderstorm WarningPHIAtlantic, Burlington, Camden, Ocean45 min
Jul 6, 11:39 PM EDTSpecial Marine WarningPHI66 min
Jul 6, 11:55 PM EDTSpecial Weather StatementPHIMonmouth50 min
Jul 7, 12:01 AM EDTAreal Flood AdvisoryPHIMiddlesex, Monmouth71 min
Jul 7, 12:10 AM EDTSpecial Marine WarningPHI95 min
Jul 7, 11:19 AM EDTTropical Storm WatchPHIAtlantic, Burlington, Cape May, Monmouth, Ocean18 hr
Jul 7, 3:32 PM EDTFlash Flood WatchPHIAtlantic, Burlington, Camden, Cape May, Cumberland, Gloucester and 10 more42 hr
Jul 6, 8:16 PM EDTSpecial Weather StatementPHILehigh29 min

Nearby

Special Weather Statements in Pennsylvania, 2021Every special weather statement 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.