Severe Thunderstorm Warning 166, NWS Philadelphia/Mount Holly

Issued

Aug 18, 2017, 5:11 PM EDT (21:11 UTC)

Expired

Aug 18, 2017, 6:00 PM EDT

In force

49 min

Issued by

NWS Philadelphia/Mount Holly

Area

Storm-based polygon

Tornado

Possible

Hail

0.75 in

Wind

60.0 mph

Counties Hunterdon County, NJ, Mercer County, NJ, Somerset County, NJ, Bucks County, PA, Chester County, PA, Delaware County, PA, Montgomery County, PA, Philadelphia County, PA

The Philadelphia radar (KDIX), 58 km from the middle of the area, began a volume at 21:12 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.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

769 
WUUS51 KPHI 182111
SVRPHI
NJC019-021-035-PAC017-029-045-091-101-182200-
/O.NEW.KPHI.SV.W.0166.170818T2111Z-170818T2200Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
511 PM EDT FRI AUG 18 2017

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Southeastern Hunterdon County in northwestern New Jersey...
  Northwestern Mercer County in central New Jersey...
  Southwestern Somerset County in northern New Jersey...
  Montgomery County in southeastern Pennsylvania...
  Bucks County in southeastern Pennsylvania...
  Northeastern Chester County in southeastern Pennsylvania...
  Northern Philadelphia County in southeastern Pennsylvania...
  Northern Delaware County in southeastern Pennsylvania...

* Until 600 PM EDT

* At 510 PM EDT, severe thunderstorms were located along a line
  extending from near Quakertown to near Chester Springs, moving east
  at 40 mph.

  HAZARD...60 mph wind gusts and penny size hail. 

  SOURCE...Radar indicated. 

  IMPACT...Expect damage to trees and power lines. 

* Locations impacted include...
  Philadelphia, Trenton, Somerville, Bensalem, Ewing, Norristown,
  Phoenixville, Lansdale, West Norriton, Middlesex, East Norriton,
  Princeton, Bound Brook, Manville, Bristol, Quakertown, Perkasie,
  Doylestown, Byram and Conshohocken.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Intense thunderstorm lines can produce brief tornadoes and widespread
significant wind damage. Although a tornado is not immediately
likely, it is best to move to an interior room on the lowest floor of
a building. These storms may cause serious injury and significant
property damage.

In addition to large hail and damaging winds...frequent cloud to
ground lightning is occurring with this storm. Move indoors
immediately. Remember...if you can hear thunder...you are close
enough to be struck by lightning.

&&

LAT...LON 4008 7487 4007 7494 4001 7505 4004 7570
      4050 7537 4057 7453 4053 7450
TIME...MOT...LOC 2110Z 266DEG 33KT 4043 7530 4010 7555 

TORNADO...POSSIBLE
HAIL...0.75IN
WIND...60MPH
 
$$

SFJ

271 
WWUS51 KPHI 182148
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
548 PM EDT FRI AUG 18 2017

PAC029-045-182157-
/O.CAN.KPHI.SV.W.0166.000000T0000Z-170818T2200Z/
Chester PA-Delaware PA-
548 PM EDT FRI AUG 18 2017

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN CHESTER AND
NORTHERN DELAWARE COUNTIES IS CANCELLED...

The storms which prompted the warning have moved out of the warned 
area. Therefore, the warning has been cancelled.

A severe thunderstorm watch remains in effect until 900 PM EDT for
southern, central, northern and northwestern New Jersey...and
southeastern Pennsylvania.

LAT...LON 4008 7487 4007 7494 4001 7505 4002 7533
      4007 7536 4007 7540 4052 7511 4057 7453
      4053 7450
TIME...MOT...LOC 2147Z 233DEG 30KT 4048 7494 4015 7519 

$$

NJC019-021-035-PAC017-091-101-182200-
/O.CON.KPHI.SV.W.0166.000000T0000Z-170818T2200Z/
Hunterdon NJ-Mercer NJ-Somerset NJ-Montgomery PA-Bucks PA-
Philadelphia PA-
548 PM EDT FRI AUG 18 2017

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 600 PM EDT
FOR SOUTHEASTERN HUNTERDON...NORTHWESTERN MERCER...SOUTHWESTERN
SOMERSET...SOUTHEASTERN MONTGOMERY...CENTRAL BUCKS AND NORTHERN
PHILADELPHIA COUNTIES...

At 547 PM EDT, severe thunderstorms were located along a line
extending from Sand Brook to Ambler, moving northeast at 35 mph.

HAZARD...60 mph wind gusts and penny size hail. 

SOURCE...Radar indicated. 

IMPACT...Expect damage to trees and power lines. 

Locations impacted include...
Philadelphia, Trenton, Somerville, Bensalem, Ewing, Norristown,
Lansdale, West Norriton, Middlesex, East Norriton, Princeton, Bound
Brook, Manville, Bristol, Doylestown, Byram, Conshohocken, Hatboro,
Ambler and Flemington.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Remain alert for a possible tornado! Tornadoes can develop quickly
from severe thunderstorms. If you spot a tornado go at once into the
basement or small central room in a sturdy structure.

To report severe weather contact your nearest law enforcement agency.
They will send your report to the National Weather Service office in
Mount Holly NJ.

&&

LAT...LON 4008 7487 4007 7494 4001 7505 4002 7533
      4007 7536 4007 7540 4052 7511 4057 7453
      4053 7450
TIME...MOT...LOC 2147Z 233DEG 30KT 4048 7494 4015 7519 

TORNADO...POSSIBLE
HAIL...0.75IN
WIND...60MPH
 
$$

SFJ

Severe Thunderstorm Warnings in Pennsylvania, 2017Severe Thunderstorm Warnings in New Jersey, 2017Every severe thunderstorm warning in 2017

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.