Alert archive / Pennsylvania / Tornado Warnings in 2023

Tornado Warning 27, NWS Philadelphia/Mount Holly

July 16, 2023Montgomery County, Philadelphia County, Pennsylvania

NWS Philadelphia/Mount Holly issued this tornado warning at Jul 16, 2023, 9:53 AM EDT for Montgomery County, Philadelphia County, Pennsylvania. It was in force for 37 min. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Jul 16, 2023, 9:53 AM EDT (13:53 UTC)
Expired
Jul 16, 2023, 10:30 AM EDT
In force
37 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Tornado
Radar indicated
Hail
0.0 in

Counties Montgomery County, PA, Philadelphia County, PA

The radar

The Philadelphia radar (KDIX), 67 km from the middle of the area, began a volume at 13:54 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 was reported inside it

TimeReportWhereRemark
Jul 16, 9:54 AM EDTTSTM WND DMG1 Wnw Shawmont, PAPicture of trees down along Spring Lane and Hagys Mill Road. Time estimated from radar.

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

The nearest sounding before it

Brookhaven, NY (KOKX), launched 12:00Z, 1.9 hours before the alert went out and 215 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 12:00Z on 2023-07-16Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 236 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Brookhaven, NY at 12:00Z on 2023-07-16The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 193 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
236 J/kg
Mixed-layer CIN
-31 J/kg
Mixed-layer LCL
766 m above ground
0-6 km bulk shear
41 kt
0-1 km storm-relative helicity
193 m²/s²
0-3 km storm-relative helicity
223 m²/s²
Significant tornado parameter
0.2
Supercell composite
6.0

Open this sounding in Storm Lab

The text

As transmitted.

358 
WFUS51 KPHI 161353
TORPHI
PAC091-101-161430-
/O.NEW.KPHI.TO.W.0027.230716T1353Z-230716T1430Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Mount Holly NJ
953 AM EDT Sun Jul 16 2023

The National Weather Service in Mount Holly NJ has issued a

* Tornado Warning for...
  Southeastern Montgomery County in southeastern Pennsylvania...
  Northwestern Philadelphia County in southeastern Pennsylvania...

* Until 1030 AM EDT.
    
* At 953 AM EDT, a severe thunderstorm capable of producing a tornado
  was located over Narberth, or 7 miles west of Philadelphia, moving
  northeast at 10 mph.

  HAZARD...Tornado.

  SOURCE...Radar indicated rotation.

  IMPACT...Flying debris will be dangerous to those caught without 
           shelter. Mobile homes will be damaged or destroyed. 
           Damage to roofs, windows, and vehicles will occur.  Tree 
           damage is likely.

* Locations impacted include...
  Philadelphia, Conshohocken, Ambler, Jenkintown, Narberth,
  Rockledge, Plymouth Meeting, Germantown, Bryn Mawr, Chestnut Hill,
  Roxborough, West Conshohocken, Penn Wynne, Fort Washington,
  Glenside, Flourtown, Ardmore, Oreland, Wyndmoor and Wyncote.

This includes the following highways...
 Pennsylvania Turnpike between mile markers 334 and 340.
 Interstate 76 in Pennsylvania between mile markers 331 and 339.
 Interstate 476 in Pennsylvania between mile markers 15 and 17.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4006 7504 3998 7528 4005 7535 4018 7520
TIME...MOT...LOC 1353Z 234DEG 9KT 4004 7527 

TORNADO...RADAR INDICATED
MAX HAIL SIZE...0.00 IN

$$

MJL
2 follow-up statements
772 
WWUS51 KPHI 161407
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
1007 AM EDT Sun Jul 16 2023

PAC091-101-161430-
/O.CON.KPHI.TO.W.0027.000000T0000Z-230716T1430Z/
Montgomery PA-Philadelphia PA-
1007 AM EDT Sun Jul 16 2023

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 1030 AM EDT FOR
SOUTHEASTERN MONTGOMERY AND NORTHWESTERN PHILADELPHIA COUNTIES...
    
At 1007 AM EDT, a severe thunderstorm capable of producing a tornado
was located over Chestnut Hill, or near Philadelphia, moving
northeast at 10 mph.

HAZARD...Tornado.

SOURCE...Radar indicated rotation.

IMPACT...Flying debris will be dangerous to those caught without 
         shelter. Mobile homes will be damaged or destroyed. Damage 
         to roofs, windows, and vehicles will occur.  Tree damage is 
         likely.

Locations impacted include...
Philadelphia, Jenkintown, Rockledge, Abington, Germantown, Chestnut
Hill, Fort Washington, Glenside, Flourtown, Oreland, Wyndmoor,
Wyncote and Maple Glen.

This includes the following highways...
 Pennsylvania Turnpike between mile markers 337 and 341.
 Interstate 76 in Pennsylvania between mile markers 334 and 338.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4007 7505 4002 7523 4006 7529 4018 7519
TIME...MOT...LOC 1407Z 234DEG 9KT 4006 7523 

TORNADO...RADAR INDICATED
MAX HAIL SIZE...0.00 IN

$$

MJL
419 
WWUS51 KPHI 161421
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
1021 AM EDT Sun Jul 16 2023

PAC091-101-161431-
/O.EXP.KPHI.TO.W.0027.000000T0000Z-230716T1430Z/
Montgomery PA-Philadelphia PA-
1021 AM EDT Sun Jul 16 2023

...THE TORNADO WARNING FOR SOUTHEASTERN MONTGOMERY AND NORTHWESTERN
PHILADELPHIA COUNTIES WILL EXPIRE AT 1030 AM EDT...
                
The storm which prompted the warning has weakened below severe
limits, and no longer appears capable of producing a tornado.
Therefore, the warning will be allowed to expire.  However heavy rain
is still possible with this thunderstorm.

LAT...LON 4007 7505 4002 7523 4006 7529 4018 7519
TIME...MOT...LOC 1421Z 234DEG 9KT 4008 7519 

$$

MJL

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 15, 8:37 PM EDTAreal Flood AdvisoryPHICarbon19 min
Jul 15, 8:44 PM EDTSevere Thunderstorm WarningPHICarbon, Monroe30 min
Jul 15, 8:56 PM EDTFlash Flood WarningPHICarbon95 min
Jul 16, 12:50 AM EDTSpecial Weather StatementPHIBerks25 min
Jul 16, 1:41 AM EDTSpecial Weather StatementPHICarbon, Lehigh34 min
Jul 16, 2:12 AM EDTSpecial Weather StatementPHICarbon, Lehigh, Monroe33 min
Jul 16, 2:43 AM EDTFlash Flood WarningPHICarbon, Lehigh, Monroe, Northampton4 hr
Jul 16, 2:47 AM EDTSpecial Weather StatementPHIChester, Delaware28 min
Jul 16, 3:40 AM EDTFlash Flood WarningPHIMonroe, Northampton7 hr
Jul 16, 4:05 AM EDTFlash Flood WarningPHIBerks, Bucks, Chester, Lehigh, Montgomery, Northampton6 hr
Jul 16, 4:14 AM EDTSpecial Weather StatementPHIBucks31 min
Jul 16, 4:38 AM EDTTornado WarningPHIBucks37 min
Jul 16, 9:12 AM EDTFlash Flood WarningPHIChester2 hr
Jul 16, 9:40 AM EDTFlash Flood WarningPHIBucks, Chester, Delaware, Montgomery, Philadelphia3 hr
Jul 16, 10:54 AM EDTAreal Flood WarningPHIMonroe, Northampton5 hr
Jul 16, 11:08 AM EDTFlash Flood WarningPHIDelaware, Philadelphia3 hr
Jul 16, 12:22 PM EDTAreal Flood AdvisoryPHIBucks, Philadelphia3 hr
Jul 16, 12:26 PM EDTAreal Flood AdvisoryPHIPhiladelphia3 hr
Jul 16, 1:47 PM EDTAreal Flood AdvisoryPHIDelaware, Philadelphia80 min
Jul 16, 6:44 PM EDTAreal Flood AdvisoryPHIBucks90 min

Nearby

Tornado Warnings in Pennsylvania, 2023Every tornado warning in 2023Tornadoes in 2023

Sources

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.