Alert archive / Pennsylvania / Snow Squall Warnings in 2020
Snow Squall Warning 4, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this snow squall warning at Jan 8, 2020, 8:28 AM EST for 4 states. It was in force for 47 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
- Jan 8, 2020, 8:28 AM EST (13:28 UTC)
- Expired
- Jan 8, 2020, 9:15 AM EST
- In force
- 47 min
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
Counties New Castle County, DE, Cecil County, MD, Kent County, MD, Cumberland County, NJ, Gloucester County, NJ, Salem County, NJ, Chester County, PA, Delaware County, PA, Montgomery County, PA, Philadelphia County, PA
The radar
The Dover AFB radar (KDOX), 104 km from the middle of the area, began a volume at 13:30 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.
The nearest sounding before it
Washington/Dulle, VA (KIAD), launched 12:00Z, 1.5 hours before the alert went out and 149 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
- 1404 m above ground
- 0-6 km bulk shear
- 103 kt
- 0-1 km storm-relative helicity
- 348 m²/s²
- 0-3 km storm-relative helicity
- 424 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
736
WWUS51 KPHI 081328
SQWPHI
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Snow Squall Warning
National Weather Service Mount Holly NJ
828 AM EST Wed Jan 8 2020
PAC011-017-029-045-091-081415-
/O.NEW.KPHI.SQ.W.0003.200108T1328Z-200108T1415Z/
Berks PA-Montgomery PA-Bucks PA-Chester PA-Delaware PA-
828 AM EST Wed Jan 8 2020
The National Weather Service in Mount Holly NJ has issued a
* Snow Squall Warning for...
Southeastern Berks County in eastern Pennsylvania...
Montgomery County in southeastern Pennsylvania...
Southwestern Bucks County in southeastern Pennsylvania...
Northeastern Chester County in southeastern Pennsylvania...
Northeastern Delaware County in southeastern Pennsylvania...
* Until 915 AM EST.
* At 828 AM EST, a dangerous snow squall was located near Elverson,
or 11 miles southeast of Reading, moving east at 45 mph.
HAZARD...Extremely poor visibility in heavy snow and blowing snow.
Wind gusts up to 30 mph.
SOURCE...Radar indicated.
IMPACT...Dangerous life-threatening travel.
* This includes the following highways...
Interstate 476 in Pennsylvania between mile markers 10 and 19.
Pennsylvania Turnpike between exits 298 and 333.
Northeast Extension between exits A20 and A31.
Interstate 176 in Pennsylvania between mile markers 1 and 11.
Interstate 76 in Pennsylvania between mile markers 327 and 335.
Locations impacted include...
Reading, Norristown, Pottstown, Phoenixville, Lansdale, West
Norriton, East Norriton, Wyomissing, Conshohocken, Souderton,
Birdsboro, Collegeville, Royersford, Chalfont, Sinking Spring,
Trappe, Hatfield, Wernersville, Schwenksville and Elverson.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Consider avoiding or delaying travel until the snow squall passes
your location. If you must travel, use extra caution and allow extra
time. Rapid changes in visibility and slick road conditions may lead
to accidents.
&&
LAT...LON 4033 7520 3998 7528 4012 7592 4014 7588
4034 7617
TIME...MOT...LOC 1328Z 274DEG 37KT 4020 7578
$$
Staarmann2 follow-up statements
782
WWUS51 KPHI 081352
SQWPHI
Snow Squall Warning
National Weather Service Mount Holly NJ
850 AM EST Wed Jan 8 2020
DEC003-MDC015-029-NJC011-015-033-PAC029-045-091-101-081415-
/O.CON.KPHI.SQ.W.0004.000000T0000Z-200108T1415Z/
New Castle DE-Kent MD-Cecil MD-Cumberland NJ-Salem NJ-Gloucester NJ-
Montgomery PA-Chester PA-Philadelphia PA-Delaware PA-
850 AM EST Wed Jan 8 2020
...A SNOW SQUALL WARNING REMAINS IN EFFECT UNTIL 915 AM EST FOR NEW
CASTLE...NORTHEASTERN KENT...CECIL...NORTHWESTERN CUMBERLAND...
SALEM...NORTHWESTERN GLOUCESTER...SOUTHEASTERN MONTGOMERY...SOUTHERN
CHESTER...SOUTHWESTERN PHILADELPHIA AND DELAWARE COUNTIES...
At 850 AM EST, a dangerous snow squall was located along a line
extending from near Kennett Square to near Middletown, moving east
at 55 mph. Roads will rapidly become snow covered when this squall
passes.
HAZARD...Extremely poor visibility in heavy snow.
SOURCE...Radar and webcams.
IMPACT...Dangerous life-threatening travel.
This includes the following highways...
Interstate 295 in New Jersey between mile markers 0 and 20.
Interstate 95 in Pennsylvania between mile markers 0 and 14.
Interstate 95 in Maryland between mile markers 91 and 109.
New Jersey Turnpike between exits 1 and 2.
Interstate 95 in Delaware between mile markers 0 and 23.
Interstate 476 in Pennsylvania between mile markers 0 and 9.
Locations impacted include...
Philadelphia, Wilmington, Newark, Bridgeton, Middletown, Elkton,
Havre De Grace, Calvert, Chester, Pennsville, Yeadon, Westtown,
Carneys Point, Folcroft, Swarthmore, Elsmere, Paulsboro, Kennett
Square, New Castle and Penns Grove.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Consider avoiding or delaying travel until the snow squall passes
your location. If you must travel, use extra caution and allow extra
time. Rapid changes in visibility and slick road conditions may lead
to accidents.
There is no safe place on a highway when a snow squall hits.
Visibility and traction are immediately lost in whiteout conditions,
making it difficult or impossible to slow down and avoid stopped
vehicles. Delay travel or safely exit the highway before the snow
squall arrives.
&&
LAT...LON 3973 7610 3986 7590 4002 7522 3936 7516
3937 7606 3943 7600 3946 7601 3952 7598
3955 7603 3955 7609 3959 7611 3966 7618
3972 7620
TIME...MOT...LOC 1350Z 272DEG 48KT 3989 7566 3938 7570
$$
JEO675
WWUS51 KPHI 081410
SQWPHI
Snow Squall Warning
National Weather Service Mount Holly NJ
909 AM EST Wed Jan 8 2020
DEC003-MDC015-029-NJC011-015-033-PAC029-045-091-101-081419-
/O.EXP.KPHI.SQ.W.0004.000000T0000Z-200108T1415Z/
New Castle DE-Kent MD-Cecil MD-Cumberland NJ-Salem NJ-Gloucester NJ-
Montgomery PA-Chester PA-Philadelphia PA-Delaware PA-
909 AM EST Wed Jan 8 2020
...THE SNOW SQUALL WARNING FOR NEW CASTLE...NORTHEASTERN KENT...
CECIL...NORTHWESTERN CUMBERLAND...SALEM...NORTHWESTERN GLOUCESTER...
SOUTHEASTERN MONTGOMERY...SOUTHERN CHESTER...SOUTHWESTERN
PHILADELPHIA AND DELAWARE COUNTIES WILL EXPIRE AT 915 AM EST...
The snow squall which prompted the warning has exited the area.
Therefore, the snow squall warning will be allowed to expire. Roads
will remain snow covered.
LAT...LON 3973 7610 3986 7590 4002 7522 3936 7516
3937 7606 3943 7600 3946 7601 3952 7598
3955 7603 3955 7609 3959 7611 3966 7618
3972 7620
TIME...MOT...LOC 1409Z 272DEG 48KT 3988 7541 3937 7545
$$
JEOThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jan 8, 7:44 AM EST | Snow Squall Warning | PHI | Cecil | 46 min |
| Jan 8, 7:49 AM EST | Snow Squall Warning | PHI | Carbon, Monroe, Northampton | 41 min |
| Jan 8, 8:28 AM EST | Snow Squall Warning | PHI | Berks, Bucks, Chester, Delaware, Montgomery | 47 min |
| Jan 8, 8:30 AM EST | Snow Squall Warning | PHI | Monroe | 45 min |
| Jan 8, 11:25 AM EST | Snow Squall Warning | PHI | Berks | 35 min |
| Jan 8, 12:07 PM EST | Special Weather Statement | PHI | Montgomery | 23 min |
| Jan 8, 12:38 PM EST | Special Weather Statement | PHI | Montgomery, Philadelphia | 37 min |
| Jan 8, 12:49 PM EST | Snow Squall Warning | PHI | Chester, Delaware, Montgomery, Philadelphia | 26 min |
| Jan 8, 1:48 PM EST | Snow Squall Warning | PHI | Carbon, Monroe | 42 min |
| Jan 8, 2:05 PM EST | Special Weather Statement | PHI | Montgomery | 25 min |
| Jan 8, 2:32 PM EST | Special Weather Statement | PHI | Carbon, Northampton | 28 min |
| Jan 8, 2:33 PM EST | Special Weather Statement | PHI | Philadelphia | 27 min |
| Jan 8, 2:46 PM EST | Special Weather Statement | PHI | Berks | 44 min |
| Jan 8, 3:05 PM EST | Special Weather Statement | PHI | Northampton | 40 min |
| Jan 8, 8:48 AM EST | Snow Squall Warning | PHI | Hunterdon, Middlesex, Morris, Somerset, Warren | 42 min |
| Jan 8, 9:14 AM EST | Snow Squall Warning | PHI | Atlantic, Burlington, Camden, Cumberland, Gloucester, Salem | 46 min |
| Jan 8, 9:57 AM EST | Special Weather Statement | PHI | Atlantic | 33 min |
| Jan 8, 1:08 PM EST | Snow Squall Warning | PHI | Burlington, Camden | 37 min |
| Jan 8, 2:10 PM EST | Special Weather Statement | PHI | Sussex | 35 min |
| Jan 8, 2:18 PM EST | Snow Squall Warning | PHI | Morris, Sussex | 42 min |
| Jan 8, 4:24 PM EST | Special Weather Statement | PHI | Warren | 36 min |
| Jan 8, 6:10 PM EST | Small Craft Advisory | PHI | 13 hr | |
| Jan 8, 9:19 AM EST | Special Weather Statement | PHI | New Castle | 26 min |
Nearby
Snow Squall Warnings in Pennsylvania, 2020Snow Squall Warnings in New Jersey, 2020Snow Squall Warnings in Maryland, 2020Every snow squall warning in 2020
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.