Alert archive / Pennsylvania / Snow Squall Warnings in 2019
Snow Squall Warning 9, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this snow squall warning at Dec 18, 2019, 11:49 PM EST for Bucks County, Montgomery County, Philadelphia County, Pennsylvania. It was in force for 26 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
- Dec 18, 2019, 11:49 PM EST (04:49 UTC)
- Expired
- Dec 19, 2019, 12:15 AM EST
- In force
- 26 min
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
Counties Bucks County, PA, Montgomery County, PA, Philadelphia County, PA
The radar
The Philadelphia radar (KDIX), 49 km from the middle of the area, began a volume at 04:49 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, 4.8 hours before the alert went out and 191 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
- 995 m above ground
- 0-6 km bulk shear
- 94 kt
- 0-1 km storm-relative helicity
- -100 m²/s²
- 0-3 km storm-relative helicity
- -67 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
294
WWUS51 KPHI 190451
SQWPHI
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Snow Squall Warning
National Weather Service Mount Holly NJ
1149 PM EST Wed Dec 18 2019
PAC017-091-101-190515-
/O.NEW.KPHI.SQ.W.0009.191219T0449Z-191219T0515Z/
Montgomery PA-Bucks PA-Philadelphia PA-
1149 PM EST Wed Dec 18 2019
The National Weather Service in Mount Holly NJ has issued a
* Snow Squall Warning for...
Northeastern Montgomery County in southeastern Pennsylvania...
Southern Bucks County in southeastern Pennsylvania...
Northeastern Philadelphia County in southeastern Pennsylvania...
* Until 1215 AM EST.
* At 1149 PM EST, a dangerous snow squall was located along a line
extending from near Souderton to Newtown, moving southeast at 40
mph.
HAZARD...Whiteout conditions. Near zero visibility in snow and
blowing snow. Wind gusts up to 30 mph.
SOURCE...Public and surface observations reports.
IMPACT...Dangerous life-threatening travel.
* This includes the following highways...
Interstate 95 in Pennsylvania between mile markers 32 and 40.
Pennsylvania Turnpike between exits 343 and 353.
Locations impacted include...
Philadelphia, Trenton, Bensalem, Ewing, Burlington, Bristol,
Perkasie, Doylestown, Hatboro, Souderton, Chalfont, Hatfield,
Yardley, Newtown, Tullytown, Langhorne, Bryn Athyn, Ivyland,
Feasterville-Trevose and Fricks.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Reduce your speed and turn on headlights! During snow squalls, the
visibility may suddenly drop to near zero in whiteout conditions.
Slow Down! Rapid changes in visibility and road conditions are
expected with this dangerous snow squall. Be alert for sudden
whiteout conditions.
&&
LAT...LON 4012 7478 4013 7482 4010 7484 4008 7487
4007 7494 4004 7499 4012 7510 4037 7540
4034 7498 4021 7476 4015 7472
TIME...MOT...LOC 0449Z 312DEG 36KT 4034 7534 4022 7495
$$
Gorse1 follow-up statement
258
WWUS51 KPHI 190503
SQWPHI
Snow Squall Warning
National Weather Service Mount Holly NJ
1202 AM EST Thu Dec 19 2019
PAC017-091-101-190515-
/O.CON.KPHI.SQ.W.0009.000000T0000Z-191219T0515Z/
Montgomery PA-Bucks PA-Philadelphia PA-
1202 AM EST Thu Dec 19 2019
...A SNOW SQUALL WARNING REMAINS IN EFFECT UNTIL 1215 AM EST FOR EAST
CENTRAL MONTGOMERY...SOUTHEASTERN BUCKS AND NORTHEASTERN PHILADELPHIA
COUNTIES...
At 1202 AM EST, a dangerous snow squall was located along a line
extending from near Chalfont to Levittown, moving southeast at 40
mph.
HAZARD...Poor visibility in snow and blowing snow. Wind gusts up to
30 mph.
SOURCE...Radar and webcams.
IMPACT...Expect hazardous road conditions.
This includes the following highways...
Interstate 95 in Pennsylvania between mile markers 32 and 40.
Pennsylvania Turnpike between exits 343 and 353.
Locations impacted include...
Philadelphia, Trenton, Bensalem, Burlington, Bristol, Hatboro,
Yardley, Newtown, Tullytown, Langhorne, Bryn Athyn, Ivyland,
Feasterville-Trevose, Willow Grove, Northeast Philadelphia,
Feasterville, Woodside, Richboro, Andalusia and Langhorn.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Reduce your speed and turn on headlights! During snow squalls, the
visibility may suddenly drop to near zero in whiteout conditions.
Slow Down! Rapid changes in visibility and road conditions are
expected with this dangerous snow squall. Be alert for sudden
whiteout conditions.
&&
LAT...LON 4012 7478 4013 7482 4010 7484 4008 7487
4007 7494 4004 7499 4012 7510 4027 7527
4030 7499 4021 7476 4015 7472
TIME...MOT...LOC 0502Z 312DEG 36KT 4027 7524 4015 7485
$$
GorseThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Dec 19, 12:09 AM EST | Snow Squall Warning | PHI | Bucks, Montgomery, Philadelphia | 36 min |
Nearby
Snow Squall Warnings in Pennsylvania, 2019Every snow squall warning in 2019
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.