Alert archive / Pennsylvania / Snow Squall Warnings in 2019

Snow Squall Warning 7, NWS State College, PA

December 18, 2019Potter County, Tioga County, Pennsylvania

NWS State College, PA issued this snow squall warning at Dec 18, 2019, 10:32 AM EST for Potter County, Tioga County, Pennsylvania. It was in force for 43 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Dec 18, 2019, 10:32 AM EST (15:32 UTC)
Expired
Dec 18, 2019, 11:15 AM EST
In force
43 min
Issued by
NWS State College, PA
Area
Storm-based polygon

Counties Potter County, PA, Tioga County, PA

The radar

The State College radar (KCCX), 100 km from the middle of the area, began a volume at 15:35 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

Buffalo Intl Airport, NY (KBUF), launched 12:00Z, 3.5 hours before the alert went out and 160 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, Buffalo Intl Airport, NY at 12:00Z on 2019-12-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Buffalo Intl Airport, NY at 12:00Z on 2019-12-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -86 square meters per square second.1939587897117Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1343 m above ground
0-6 km bulk shear
75 kt
0-1 km storm-relative helicity
-86 m²/s²
0-3 km storm-relative helicity
42 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this snow squall warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS State College, PA wrote its last area forecast discussion before this snow squall warning went out at Dec 18, 9:57 AM EST, 35 minutes earlier.

Area forecast discussion, Dec 18, 9:57 AM EST, 35 minutes before
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Hazardous weather outlook, Dec 18, 4:05 AM EST, 6 hours 27 minutes before
Hazardous Weather Outlook
National Weather Service State College PA
405 AM EST Wed Dec 18 2019

PAZ004-005-190915-
Warren-McKean-
405 AM EST Wed Dec 18 2019

...WINTER WEATHER ADVISORY IN EFFECT UNTIL 7 AM EST THURSDAY...

This Hazardous Weather Outlook is for central Pennsylvania.

.DAY ONE...Today and tonight.

Please listen to NOAA Weather Radio or go to
weather.gov/StateCollege on the internet for more
information about the following hazards.

   Winter Weather Advisory.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday.

Please listen to NOAA Weather Radio or go to
weather.gov/StateCollege on the internet for more
information about the following hazards.

   Winter Weather Advisory.

.SPOTTER INFORMATION STATEMENT...

Spotters are encouraged to report snowfall to the National Weather
Service in State College PA via the Internet or Phone.

PAZ006-010-011-190915-
Potter-Elk-Cameron-
405 AM EST Wed Dec 18 2019

This Hazardous Weather Outlook is for central Pennsylvania.

.DAY ONE...Today and tonight.

Frequent snow showers and brief heavier snow squalls today and
tonight will bring total snow accumulations of 1 to 3 inches. Gusty
west to northwest winds of 30 to 35 mph will cause locally reduced
visibility from the combination of falling and blowing snow.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday.

The probability for widespread hazardous weather is low.

.SPOTTER INFORMATION STATEMENT...

Spotters are encouraged to report snowfall to the National Weather
Service in State College PA via the Internet or Phone.

PAZ012-017-018-024-033-037-041-042-190915-
Northern Clinton-Clearfield-Northern Centre-Cambria-Somerset-Tioga-
Northern Lycoming-Sullivan-
405 AM EST Wed Dec 18 2019

This Hazardous Weather Outlook is for central Pennsylvania.

.DAY ONE...Today and tonight.

Frequent snow showers will occur from late this morning through the
afternoon hours. Scattered snow squalls are also possible,
potentially resulting in dangerous driving conditions. Total snow
accumulation of 1 to 2 inches is expected by late tonight.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday.

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Spotters are encouraged to report snowfall to the National Weather
Service in State College PA via the Internet or Phone.

PAZ019-025>028-034-035-045-046-049>053-056-058-190915-
Southern Centre-Blair-Huntingdon-Mifflin-Juniata-Bedford-Fulton-
Southern Clinton-Southern Lycoming-Union-Snyder-Montour-
Northumberland-Columbia-Perry-Schuylkill-
405 AM EST Wed Dec 18 2019

This Hazardous Weather Outlook is for central Pennsylvania.

.DAY ONE...Today and tonight.

Flurries and scattered snow showers will occur today and tonight.
Isolated, heavy snow squalls are possible during the late morning
into the mid afternoon hours today, potentially resulting in
dangerous driving conditions. Localized snow accumulation of an inch
or two is possible.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday.

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Spotters are encouraged to report snowfall to the National Weather
Service in State College PA via the Internet or Phone.

PAZ036-057-059-063>066-190915-
Franklin-Dauphin-Lebanon-Cumberland-Adams-York-Lancaster-
405 AM EST Wed Dec 18 2019

This Hazardous Weather Outlook is for central Pennsylvania.

.DAY ONE...Today and tonight.

The probability for widespread hazardous weather is low.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday.

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

Lambert

In the hours before

Special weather statement, Dec 18, 9:28 AM EST, 1 hour 4 minutes before
Special Weather Statement
National Weather Service State College PA
928 AM EST Wed Dec 18 2019

PAZ004>006-010>012-017-018-037-041-042-181730-
Warren-McKean-Potter-Elk-Cameron-Northern Clinton-Clearfield-
Northern Centre-Tioga-Northern Lycoming-Sullivan-
928 AM EST Wed Dec 18 2019

Fast moving bands of snow showers will bring a brief burst of
heavier snow to north central Pennsylvania through 1230 PM. The
snow will come down hard for a brief time and gusty winds will
cause poor visibility. While snow amounts will not be real heavy,
the combination of the rate of fall of the snow and gusty winds
will likely produce poor travel conditions at times. Persons
traveling this morning should be alert for a wide range of
conditions.

Martin
Special weather statement, Dec 18, 10:07 AM EST, 25 minutes before
Special Weather Statement
National Weather Service State College PA
1007 AM EST Wed Dec 18 2019

PAZ005-006-037-181600-
McKean PA-Potter PA-Tioga PA-
1007 AM EST Wed Dec 18 2019

...A BAND OF HEAVY SNOW WILL AFFECT PARTS OF MCKEAN...POTTER...AND
TIOGA COUNTIES...

HAZARDS...A band of heavy snow which can rapidly reduce visibility to
near a quarter of a mile.

LOCATION AND MOVEMENT...At 1006 AM EST, a band of heavy snow was
along a line extending from Keeneyville to near Coudersport to near
Keating Summit and moving southeast at 35 MPH.

THIS BAND OF HEAVY SNOW WILL BE NEAR...
  Wellsboro and Keeneyville around 1010 AM EST.
  Cherry Springs State Park around 1020 AM EST.
  Lyman Run State Park around 1025 AM EST.
  Mansfield and Covington around 1030 AM EST.
  Galeton, Wharton and Blossburg around 1035 AM EST.
  Leonard Harrison State Park around 1050 AM EST.

SAFETY INFO...
Use extra caution if you must travel into or through this band of
heavy snow. Rapid changes in visibility and potentially slick roads
are likely to lead to accidents. Consider delaying travel until this
band of heavy snow passes your location.

&&

LAT...LON 4192 7726 4180 7690 4160 7687 4155 7696
      4154 7760 4148 7760 4148 7798 4154 7812
      4162 7820 4162 7831 4167 7844 4194 7809
TIME...MOT...LOC 1506Z 294DEG 29KT 4186 7730 4178 7793 4167 7828

Colbert/ST

The office that day

Everything else NWS State College, PA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Dec 18, 3:39 AM ESTWinter Weather AdvisoryCTPMcKean, Warren24 hr
Dec 18, 10:07 AM ESTSpecial Weather StatementCTPPotter, Tioga53 min
Dec 18, 10:46 AM ESTSpecial Weather StatementCTPCameron, Clinton, Elk59 min
Dec 18, 11:20 AM ESTSnow Squall WarningCTPLycoming, Sullivan, Tioga55 min
Dec 18, 11:54 AM ESTSpecial Weather StatementCTPClinton66 min
Dec 18, 12:03 PM ESTSpecial Weather StatementCTPCentre, Clearfield87 min
Dec 18, 2:30 PM ESTSnow Squall WarningCTPBlair, Cambria, Huntingdon, Juniata, Mifflin75 min
Dec 18, 3:53 PM ESTSpecial Weather StatementCTPBedford, Fulton, Huntingdon, Juniata, Somerset52 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.