Alert archive / Pennsylvania / Tornado Warnings in 2018

Tornado Warning 1, NWS Philadelphia/Mount Holly

May 15, 20185 counties in Pennsylvania

NWS Philadelphia/Mount Holly issued this tornado warning at May 15, 2018, 4:26 PM EDT for 5 counties in Pennsylvania. It was in force for 19 min. 8 reports 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: May 15, 2018, 4:26 PM EDT (20:26 UTC)
Expired: May 15, 2018, 4:45 PM EDT
In force: 19 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 1.0 in

Counties Berks County, PA, Bucks County, PA, Lehigh County, PA, Montgomery County, PA, Northampton County, PA

The radar

The Philadelphia radar (KDIX), 143 km from the middle of the area, began a volume at 20:30 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

Time	Report	Where	Remark
May 15, 4:39 PM EDT	TSTM WND DMG	1 Sse Fullerton, PA	DOWNED TREE AT SEVENTH STREET AND VIRGINIA AVENUE IN WHITEHALL TWP. TIME ESTIMATED FROM RADAR.
May 15, 4:40 PM EDT	TSTM WND DMG	North Catasauqua, PA	NUMEROUS TREES AND POWER LINES DOWN IN N CATASAUQUA. A WIND GUST OF 57 MPH WAS ALSO MEAUSURED DURING THIS TIME. TIME ESTIMATED FROM RADAR
May 15, 4:42 PM EDT	TSTM WND DMG	1 Ne Griesemersville, PA	ROOF COLLAPSE FROM STRONG WINDS.
May 15, 4:45 PM EDT	TSTM WND GST 68	Lower Macungie Twp, PA	WIND GUST OF 68 MPH MEASURED WITH HAND HELD ANEMOMETER...HOWEVER THE DEVICE HAD NOT BEEN CALIBRATED RECENTLY. TREE DAMAGE ALSO REPORTED
May 15, 4:46 PM EDT	TSTM WND GST 55	1 S Ruscomb Manor Twp, PA	CWOP STATION REPORTS WIND GUST OF 55 MPH
May 15, 4:50 PM EDT	TSTM WND DMG	North Catasauqua, PA	THREE-FOOT DIAMETER TREE FELL ONTO AND DAMAGED TWO DUMPSTERS AND A FENCE.
May 15, 4:52 PM EDT	TSTM WND GST 59	S Allentown, PA	TRAINED SPOTTER REPORTS WIND GUST OF 59 MPH MEASURED WITH A HANDHELD ANEMOMETER. PEA SIZE HAIL WAS ALSO FALLING AT THE TIME
May 15, 4:52 PM EDT	HAIL 0.75	1 S Allentown, PA	DIME SIZE HAIL IN S ALLENTOWN

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

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
May 15, 1:46 PM EDT	Severe Thunderstorm Watch	SPC	9 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 8.4 hours before the alert went out and 219 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 47 J/kg
Mixed-layer CIN: -484 J/kg
Mixed-layer LCL: 1259 m above ground
0-6 km bulk shear: 21 kt
0-1 km storm-relative helicity: 117 m²/s²
0-3 km storm-relative helicity: 79 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

064 
WFUS51 KPHI 152026
TORPHI
PAC011-017-077-091-095-152100-
/O.NEW.KPHI.TO.W.0001.180515T2026Z-180515T2100Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Mount Holly NJ
426 PM EDT TUE MAY 15 2018

The National Weather Service in Mount Holly NJ has issued a

* Tornado Warning for...
  Northeastern Berks County in eastern Pennsylvania...
  Northwestern Montgomery County in southeastern Pennsylvania...
  Lehigh County in eastern Pennsylvania...
  Northwestern Bucks County in southeastern Pennsylvania...
  Southwestern Northampton County in eastern Pennsylvania...

* Until 500 PM EDT.
    
* At 426 PM EDT, a severe thunderstorm capable of producing a tornado
  was located over Shoemakersville, or 11 miles north of Reading,
  moving east at 60 mph.

  HAZARD...Tornado and quarter size hail.

  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.

* This dangerous storm will be near...
  Reading, Laureldale and Lenhartsville around 430 PM EDT.
  Fleetwood around 435 PM EDT.
  Kutztown, Topton and Lyons around 440 PM EDT.
  Bechtelsville around 445 PM EDT.
  Bally, Zionsville and Ancient Oaks around 450 PM EDT.
  East Greenville, Green Lane and Geryville around 455 PM EDT.
  Quakertown around 500 PM EDT.

Other locations impacted by this tornadic thunderstorm include
Harleysville, Coopersburg, Alburtis, Boyertown, Coplay, Fountain
Hill, Fullerton, Hokendauqua, Red Hill and Macungie.

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.

This cluster of thunderstorms is capable of producing tornadoes and
widespread significant wind damage. Do not wait to see or hear the
tornado. For your protection move to an interior room on the lowest
floor of a building.

&&

LAT...LON 4056 7610 4058 7605 4057 7602 4063 7600
      4065 7596 4072 7533 4026 7537 4040 7613
TIME...MOT...LOC 2026Z 276DEG 54KT 4049 7601 

TORNADO...RADAR INDICATED
HAIL...1.00IN

$$

SFJ

2 follow-up statements

212 
WWUS51 KPHI 152038
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
438 PM EDT TUE MAY 15 2018

PAC011-017-077-091-095-152100-
/O.CON.KPHI.TO.W.0001.000000T0000Z-180515T2100Z/
Berks PA-Montgomery PA-Lehigh PA-Bucks PA-Northampton PA-
438 PM EDT TUE MAY 15 2018

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 500 PM EDT FOR
NORTHEASTERN BERKS...NORTHWESTERN MONTGOMERY...LEHIGH...NORTHWESTERN
BUCKS AND SOUTHWESTERN NORTHAMPTON COUNTIES...
    
At 438 PM EDT, a severe thunderstorm capable of producing a tornado
was located over Lyons, or 12 miles northeast of Reading, moving east
at 60 mph.

HAZARD...Tornado and quarter size hail.

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.

This dangerous storm will be near...
  Bechtelsville around 445 PM EDT.
  Emmaus, Bally, Zionsville and Ancient Oaks around 450 PM EDT.
  East Greenville, Green Lane and Geryville around 455 PM EDT.
  Quakertown around 500 PM EDT.

Other locations impacted by this tornadic thunderstorm include
Harleysville, Coopersburg, Alburtis, Boyertown, Coplay, Fountain
Hill, Fullerton, Hokendauqua, Red Hill and Macungie.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

This cluster of thunderstorms is capable of producing tornadoes and
widespread significant wind damage. Do not wait to see or hear the
tornado. For your protection move to an interior room on the lowest
floor of a building.

&&

LAT...LON 4054 7590 4067 7572 4072 7533 4026 7537
      4038 7603 4051 7600
TIME...MOT...LOC 2038Z 276DEG 54KT 4047 7577 

TORNADO...RADAR INDICATED
HAIL...1.00IN

$$

SFJ

460 
WWUS51 KPHI 152045 RRA
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
445 PM EDT TUE MAY 15 2018

PAC011-017-077-091-095-152054-
/O.CAN.KPHI.TO.W.0001.000000T0000Z-180515T2100Z/
Berks PA-Montgomery PA-Lehigh PA-Bucks PA-Northampton PA-
445 PM EDT TUE MAY 15 2018

...THE TORNADO WARNING FOR NORTHEASTERN BERKS...NORTHWESTERN
MONTGOMERY...LEHIGH...NORTHWESTERN BUCKS AND SOUTHWESTERN NORTHAMPTON
COUNTIES IS CANCELLED...
    
The tornado threat has diminished and the Tornado Warning has been
cancelled. However, large hail and damaging winds remain likely and a
Severe Thunderstorm Warning remains in effect for the area.

A severe thunderstorm watch remains in effect until 1100 PM EDT for
eastern and southeastern Pennsylvania.


LAT...LON 4054 7590 4067 7572 4072 7533 4026 7537
      4038 7603 4051 7600
TIME...MOT...LOC 2042Z 276DEG 54KT 4046 7564 

$$

SFJ

The office that day

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

Issued	Product	Office	Counties	Lasted
May 15, 3:40 AM EDT	Flash Flood Watch	PHI	Berks, Bucks, Chester, Delaware, Lehigh, Montgomery and 1 more	21 hr
May 15, 2:49 PM EDT	Special Weather Statement	PHI	Berks, Carbon, Lehigh, Monroe, Northampton	56 min
May 15, 3:20 PM EDT	Severe Thunderstorm Warning	PHI	Carbon, Monroe	55 min
May 15, 3:46 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Lehigh, Northampton	74 min
May 15, 4:12 PM EDT	Severe Thunderstorm Warning	PHI	Carbon, Monroe	33 min
May 15, 4:24 PM EDT	Special Weather Statement	PHI	Berks	51 min
May 15, 4:41 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Bucks, Chester, Lehigh, Montgomery, Northampton	64 min
May 15, 5:12 PM EDT	Severe Thunderstorm Warning	PHI	Chester	63 min
May 15, 5:14 PM EDT	Areal Flood Advisory	PHI	Berks, Chester, Montgomery	2 hr
May 15, 5:22 PM EDT	Severe Thunderstorm Warning	PHI	Bucks, Chester, Delaware, Montgomery, Philadelphia	38 min
May 15, 5:31 PM EDT	Areal Flood Advisory	PHI	Bucks, Lehigh, Montgomery	3 hr
May 15, 5:35 PM EDT	Areal Flood Advisory	PHI	Bucks, Chester, Delaware, Montgomery, Philadelphia	4 hr
May 15, 5:38 PM EDT	Severe Thunderstorm Warning	PHI	Delaware, Philadelphia	67 min
May 15, 5:53 PM EDT	Severe Thunderstorm Warning	PHI	Bucks, Chester, Delaware, Montgomery, Philadelphia	52 min
May 15, 6:10 PM EDT	Areal Flood Advisory	PHI	Philadelphia	4 hr
May 15, 6:15 PM EDT	Severe Thunderstorm Warning	PHI	Chester	60 min
May 15, 6:35 PM EDT	Severe Thunderstorm Warning	PHI	Chester	40 min
May 15, 6:58 PM EDT	Areal Flood Advisory	PHI	Chester	4 hr

Nearby

Tornado Warnings in Pennsylvania, 2018 Every tornado warning in 2018 Tornadoes 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.