Alert archive / Pennsylvania / Lake Effect Snow Warnings in 2017

Lake Effect Snow Warning 2, NWS State College, PA

December 11, 2017Warren County, Pennsylvania

NWS State College, PA issued this lake effect snow warning at Dec 11, 2017, 12:02 PM EST for Warren County, Pennsylvania. It took effect at Dec 12, 2017, 7:00 AM EST. It was in force for 30 hr. 5 reports came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued
Dec 11, 2017, 12:02 PM EST (17:02 UTC)
In effect from
Dec 12, 2017, 7:00 AM EST
Expired
Dec 13, 2017, 1:00 PM EST
In force
30 hr
Issued by
NWS State College, PA

County Warren County, PA

The radar

The Buffalo radar (KBUF), 134 km from the middle of the area, began a volume at 17:04 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
Dec 12, 7:00 AM ESTSNOW 24 Sse Sugar Grove, PACO-OP OBSERVER STATION CVWP1, CHANDLERS VALLEY 1SE.
Dec 12, 7:00 AM ESTSNOW 2.81 Ne Warren, PACO-OP OBSERVER STATION WRRP1, WARREN.
Dec 12, 7:00 AM ESTSNOW 42 Se Russell, PAMESONET STATION KZAP1, KINZUA.
Dec 12, 8:30 PM ESTSNOW 5Chandlers Valley, PA
Dec 13, 8:00 AM ESTHEAVY SNOW 15.2Bear Lake, PA9 INCHES OVERNIGHT

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

The nearest sounding before it

Buffalo Intl Airport, NY (KBUF), launched 12:00Z, 5.0 hours before the alert went out and 133 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 2017-12-11Temperature 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 2017-12-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 77 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
565 m above ground
0-6 km bulk shear
80 kt
0-1 km storm-relative helicity
77 m²/s²
0-3 km storm-relative helicity
274 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

114 
WWUS41 KCTP 111702
WSWCTP

URGENT - WINTER WEATHER MESSAGE
National Weather Service State College PA
1202 PM EST Mon Dec 11 2017

PAZ004-120300-
/O.UPG.KCTP.WS.A.0001.171212T0000Z-171213T2100Z/
/O.NEW.KCTP.LE.W.0001.171212T1200Z-171213T1800Z/
Warren-
Including the city of Warren
1202 PM EST Mon Dec 11 2017

...LAKE EFFECT SNOW WARNING IN EFFECT FROM 7 AM TUESDAY TO 1 PM
EST WEDNESDAY...

* WHAT...Heavy lake effect snow expected. Travel will become very
  difficult Tuesday into Wednesday. Total snow accumulations of 
  10 to 15 inches are expected, with localized amounts up to 18 
  inches over extreme northwest Warren County.

* WHERE...Warren County.

* WHEN...From 7 AM Tuesday to 1 PM EST Wednesday.

* ADDITIONAL DETAILS...Winds gusting as high as 35 mph will cause
  areas of blowing and drifting snow.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

The Pennsylvania Department of Transportation and Pennsylvania
Turnpike Commission strongly encourage motorists to heed all
travel restrictions and delay unnecessary travel. Visit
www.511pa.com for the latest travel, roadway and traffic
conditions.

$$

PAZ017-024-033-120300-
/O.EXB.KCTP.WW.Y.0019.171212T1200Z-171213T1800Z/
Clearfield-Cambria-Somerset-
Including the cities of DuBois, Clearfield, Johnstown, 
and Somerset
1202 PM EST Mon Dec 11 2017

...WINTER WEATHER ADVISORY IN EFFECT FROM 7 AM TUESDAY TO 1 PM
EST WEDNESDAY...

* WHAT...4 to 8 inches of snow expected...with locally higher
  amounts possible. Plan on difficult travel conditions. 

* WHERE...Clearfield, Cambria and Somerset Counties.

* WHEN...From 7 AM Tuesday to 1 PM EST Wednesday.

* ADDITIONAL DETAILS...Winds gusting as high as 35 mph will 
  cause areas of blowing and drifting snow late Tuesday into 
  Wednesday.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

The Pennsylvania Department of Transportation and Pennsylvania
Turnpike Commission remind motorists to adjust speeds based on
driving conditions as winter weather impacts Pennsylvania
roadways. Visit www.511pa.com for the latest travel, roadway and
traffic conditions.

$$

PAZ005-010-120300-
/O.EXT.KCTP.WW.Y.0019.171212T1200Z-171213T1800Z/
McKean-Elk-
Including the cities of Bradford, St. Marys, and Ridgway
1202 PM EST Mon Dec 11 2017

...WINTER WEATHER ADVISORY NOW IN EFFECT FROM 7 AM TUESDAY TO
1 PM EST WEDNESDAY...

* WHAT...Lake effect snow expected. Plan on difficult travel
  conditions. Total snow accumulations of 4 to 8 inches, with 
  localized higher amounts possible.

* WHERE...McKean and Elk Counties.

* WHEN...From 7 AM Tuesday to 1 PM EST Wednesday.

* ADDITIONAL DETAILS...Winds gusting as high as 35 mph will 
  cause areas of blowing and drifting snow late Tuesday into 
  Wednesday.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

The Pennsylvania Department of Transportation and Pennsylvania
Turnpike Commission remind motorists to adjust speeds based on
driving conditions as winter weather impacts Pennsylvania
roadways. Visit www.511pa.com for the latest travel, roadway and
traffic conditions.

$$

DeVoir
6 follow-up statements
487 
WWUS41 KCTP 120234
WSWCTP

URGENT - WINTER WEATHER MESSAGE
National Weather Service State College PA
934 PM EST Mon Dec 11 2017


PAZ004-121045-
/O.CON.KCTP.LE.W.0001.171212T1200Z-171213T1800Z/
Warren-
Including the city of Warren
934 PM EST Mon Dec 11 2017

...LAKE EFFECT SNOW WARNING REMAINS IN EFFECT FROM 7 AM TUESDAY
TO 1 PM EST WEDNESDAY...

* WHAT...Heavy lake effect snow expected. Travel will become 
  very difficult Tuesday into Wednesday. Total snow 
  accumulations of 10 to 15 inches are expected, with localized 
  amounts up to 18 inches over extreme northwest Warren County.

* WHERE...Warren County.

* WHEN...From 7 AM Tuesday to 1 PM EST Wednesday.

* ADDITIONAL DETAILS...Winds gusting as high as 35 mph will 
  cause areas of blowing and drifting snow.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

The Pennsylvania Department of Transportation and Pennsylvania
Turnpike Commission strongly encourage motorists to heed all
travel restrictions and delay unnecessary travel. Visit
www.511pa.com for the latest travel, roadway and traffic
conditions.

$$

PAZ017-024-033-121045-
/O.CON.KCTP.WW.Y.0019.171212T1200Z-171213T1800Z/
Clearfield-Cambria-Somerset-
Including the cities of DuBois, Clearfield, Johnstown, 
and Somerset
934 PM EST Mon Dec 11 2017

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 7 AM TUESDAY TO
1 PM EST WEDNESDAY...

* WHAT...4 to 8 inches of snow expected...with locally higher 
  amounts possible. Plan on difficult travel conditions.

* WHERE...Clearfield, Cambria and Somerset Counties.

* WHEN...From 7 AM Tuesday to 1 PM EST Wednesday.

* ADDITIONAL DETAILS...Winds gusting as high as 35 mph will 
  cause areas of blowing and drifting snow late Tuesday into 
  Wednesday.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

The Pennsylvania Department of Transportation and Pennsylvania
Turnpike Commission remind motorists to adjust speeds based on
driving conditions as winter weather impacts Pennsylvania
roadways. Visit www.511pa.com for the latest travel, roadway and
traffic conditions.

$$

PAZ005-010-121045-
/O.CON.KCTP.WW.Y.0019.171212T1200Z-171213T1800Z/
McKean-Elk-
Including the cities of Bradford, St. Marys, and Ridgway
934 PM EST Mon Dec 11 2017

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 7 AM TUESDAY TO
1 PM EST WEDNESDAY...

* WHAT...Lake effect snow expected. Plan on difficult travel 
  conditions. Total snow accumulations of 4 to 8 inches, with 
  localized higher amounts possible.

* WHERE...McKean and Elk Counties.

* WHEN...From 7 AM Tuesday to 1 PM EST Wednesday.

* ADDITIONAL DETAILS...Winds gusting as high as 35 mph will 
  cause areas of blowing and drifting snow late Tuesday into 
  Wednesday.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

The Pennsylvania Department of Transportation and Pennsylvania
Turnpike Commission remind motorists to adjust speeds based on
driving conditions as winter weather impacts Pennsylvania
roadways. Visit www.511pa.com for the latest travel, roadway and
traffic conditions.

$$
800 
WWUS41 KCTP 121015
WSWCTP

URGENT - WINTER WEATHER MESSAGE
National Weather Service State College PA
515 AM EST Tue Dec 12 2017


PAZ004-121815-
/O.CON.KCTP.LE.W.0001.171212T1200Z-171213T1800Z/
Warren-
Including the city of Warren
515 AM EST Tue Dec 12 2017

...LAKE EFFECT SNOW WARNING REMAINS IN EFFECT UNTIL 1 PM EST
WEDNESDAY...

* WHAT...Heavy lake effect snow expected. Plan on difficult travel
  conditions. Total snow accumulations of 8 to 12 inches, with 
  localized amounts up to 16 inches, are expected.

* WHERE...Warren County.

* WHEN...Until 1 PM EST Wednesday.

* ADDITIONAL DETAILS...Winds gusting as high as 40 mph will cause
  areas of blowing and drifting snow.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

The Pennsylvania Department of Transportation and Pennsylvania
Turnpike Commission strongly encourage motorists to heed all
travel restrictions and delay unnecessary travel. Visit
www.511pa.com for the latest travel, roadway and traffic
conditions.

$$

PAZ017-024-033-121815-
/O.CON.KCTP.WW.Y.0019.171212T1200Z-171213T1800Z/
Clearfield-Cambria-Somerset-
Including the cities of DuBois, Clearfield, Johnstown, 
and Somerset
515 AM EST Tue Dec 12 2017

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 1 PM EST
WEDNESDAY...

* WHAT...Snow expected. Plan on difficult travel conditions. Tree
  branches could fall as well. Total snow accumulations of 2 to 5
  inches are expected. Locally up to 6 to 8 inches is possible on
  the ridges to the west of route 219. 

* WHERE...Clearfield, Cambria and Somerset Counties.

* WHEN...Until 1 PM EST Wednesday.

* ADDITIONAL DETAILS...Be prepared for reduced visibilities at
  times. Winds gusting as high as 40 mph will cause areas of 
  blowing and drifting snow.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

The Pennsylvania Department of Transportation and Pennsylvania
Turnpike Commission remind motorists to adjust speeds based on
driving conditions as winter weather impacts Pennsylvania
roadways. Visit www.511pa.com for the latest travel, roadway and
traffic conditions.

$$

PAZ005-010-121815-
/O.CON.KCTP.WW.Y.0019.171212T1200Z-171213T1800Z/
McKean-Elk-
Including the cities of Bradford, St. Marys, and Ridgway
515 AM EST Tue Dec 12 2017

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 1 PM EST
WEDNESDAY...

* WHAT...Lake effect snow expected. Plan on difficult travel 
  conditions. In addition, areas of poor visibility are expected. 
  Total snow accumulations of 3 to 5 inches, with localized 
  amounts up to 9 inches, are expected.

* WHERE...McKean and Elk Counties.

* WHEN...Until 1 PM EST Wednesday.

* ADDITIONAL DETAILS...Winds gusting as high as 40 mph will 
  cause areas of blowing and drifting snow.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

The Pennsylvania Department of Transportation and Pennsylvania
Turnpike Commission remind motorists to adjust speeds based on
driving conditions as winter weather impacts Pennsylvania
roadways. Visit www.511pa.com for the latest travel, roadway and
traffic conditions.

$$
549 
WWUS41 KCTP 121735
WSWCTP

URGENT - WINTER WEATHER MESSAGE
National Weather Service State College PA
1235 PM EST Tue Dec 12 2017

PAZ004-130145-
/O.CON.KCTP.LE.W.0001.000000T0000Z-171213T1800Z/
Warren-
Including the city of Warren
1235 PM EST Tue Dec 12 2017

...LAKE EFFECT SNOW WARNING REMAINS IN EFFECT UNTIL 1 PM EST
WEDNESDAY...

* WHAT...Heavy lake effect snow occurring. Plan on difficult
  travel conditions. Total snow accumulations of 8 to 12 inches, 
  with localized amounts up to 16 inches across the northern and 
  western sections of Warren County.

* WHERE...Warren County.

* WHEN...Until 1 PM EST Wednesday.

* ADDITIONAL DETAILS...Be prepared for significant reductions in 
  visibility at times.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

The Pennsylvania Department of Transportation and Pennsylvania
Turnpike Commission strongly encourage motorists to heed all
travel restrictions and delay unnecessary travel. Visit
www.511pa.com for the latest travel, roadway and traffic
conditions.

$$

PAZ017-024-033-130145-
/O.CON.KCTP.WW.Y.0019.000000T0000Z-171213T1800Z/
Clearfield-Cambria-Somerset-
Including the cities of DuBois, Clearfield, Johnstown, 
and Somerset
1235 PM EST Tue Dec 12 2017

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 1 PM EST
WEDNESDAY...

* WHAT...Snow occurring. Plan on difficult travel conditions.  
  Total accumulations of 2 to 5 inches, with locally up to 6 to 8 
  inches on the ridges to the west of route 219.

* WHERE...Clearfield, Cambria and Somerset Counties.

* WHEN...Until 1 PM EST Wednesday.

* ADDITIONAL DETAILS...Be prepared for reduced visibilities at 
  times.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

The Pennsylvania Department of Transportation and Pennsylvania
Turnpike Commission remind motorists to adjust speeds based on
driving conditions as winter weather impacts Pennsylvania
roadways. Visit www.511pa.com for the latest travel, roadway and
traffic conditions.

$$

PAZ005-010-130145-
/O.CON.KCTP.WW.Y.0019.000000T0000Z-171213T1800Z/
McKean-Elk-
Including the cities of Bradford, St. Marys, and Ridgway
1235 PM EST Tue Dec 12 2017

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 1 PM EST
WEDNESDAY...

* WHAT...Lake effect snow occurring. Plan on difficult travel
  conditions. Total snow accumulations of 2 to 5 inches, with 
  localized amounts up to 9 inches, are expected.

* WHERE...McKean and Elk Counties.

* WHEN...Until 1 PM EST Wednesday.

* ADDITIONAL DETAILS...Be prepared for reduced visibilities at 
  times.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

The Pennsylvania Department of Transportation and Pennsylvania
Turnpike Commission remind motorists to adjust speeds based on
driving conditions as winter weather impacts Pennsylvania
roadways. Visit www.511pa.com for the latest travel, roadway and
traffic conditions.

$$

Martin/Jung
828 
WWUS41 KCTP 130144
WSWCTP

URGENT - WINTER WEATHER MESSAGE
National Weather Service State College PA
844 PM EST Tue Dec 12 2017


PAZ024-033-130245-
/O.CAN.KCTP.WW.Y.0019.000000T0000Z-171213T1800Z/
Cambria-Somerset-
Including the cities of Johnstown and Somerset
844 PM EST Tue Dec 12 2017

...WINTER WEATHER ADVISORY IS CANCELLED...

Scattered light snow showers will continue to affect area
overnight. However, accumulations will only range from a dusting
in most spots, to perhaps an inch along the ridgetops. 

$$

PAZ004-130945-
/O.CON.KCTP.LE.W.0001.000000T0000Z-171213T1800Z/
Warren-
Including the city of Warren
844 PM EST Tue Dec 12 2017

...LAKE EFFECT SNOW WARNING REMAINS IN EFFECT UNTIL 1 PM EST
WEDNESDAY...

* WHAT...Heavy lake effect snow expected. Plan on difficult travel
  conditions. Many areas are seeing a lull in the snow this
  evening. However, it will pick up around midnight and continue
  through Wednesday morning. Additional accumulations of 3 to 6
  inches are expected, with the heaviest amounts over the
  northwest corner of Warren County.

* WHERE...Warren County.

* WHEN...Until 1 PM EST Wednesday.

* ADDITIONAL DETAILS...Be prepared for significant reductions in 
  visibility at times.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

The Pennsylvania Department of Transportation and Pennsylvania
Turnpike Commission strongly encourage motorists to heed all
travel restrictions and delay unnecessary travel. Visit
www.511pa.com for the latest travel, roadway and traffic
conditions.

$$

PAZ017-130945-
/O.CON.KCTP.WW.Y.0019.000000T0000Z-171213T1800Z/
Clearfield-
Including the cities of DuBois and Clearfield
844 PM EST Tue Dec 12 2017

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 1 PM EST
WEDNESDAY...

* WHAT...Snow expected. Plan on slippery road conditions. Snow has
  tapered off this evening. However, additional snow showers are
  expected late tonight into Wednesday morning. Additional snow 
  accumulations of up to one inch are expected.

* WHERE...Clearfield County.

* WHEN...Until 1 PM EST Wednesday.

* ADDITIONAL DETAILS...Be prepared for reduced visibilities at 
  times.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

The Pennsylvania Department of Transportation and Pennsylvania
Turnpike Commission remind motorists to adjust speeds based on
driving conditions as winter weather impacts Pennsylvania
roadways. Visit www.511pa.com for the latest travel, roadway and
traffic conditions.

$$

PAZ005-010-130945-
/O.CON.KCTP.WW.Y.0019.000000T0000Z-171213T1800Z/
McKean-Elk-
Including the cities of Bradford, St. Marys, and Ridgway
844 PM EST Tue Dec 12 2017

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 1 PM EST
WEDNESDAY...

* WHAT...Lake effect snow expected. Plan on slippery road
  conditions. Snow has tapered off this evening. However, it will
  redevelop around midnight and continue into Wednesday morning.
  Additional accumulations of 1 to 3 inches are expected.

* WHERE...McKean and Elk Counties.

* WHEN...Until 1 PM EST Wednesday.

* ADDITIONAL DETAILS...Be prepared for reduced visibilities at 
  times.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

The Pennsylvania Department of Transportation and Pennsylvania
Turnpike Commission remind motorists to adjust speeds based on
driving conditions as winter weather impacts Pennsylvania
roadways. Visit www.511pa.com for the latest travel, roadway and
traffic conditions.

$$
097 
WWUS41 KCTP 130905
WSWCTP

URGENT - WINTER WEATHER MESSAGE
National Weather Service State College PA
405 AM EST Wed Dec 13 2017


PAZ004-131800-
/O.NEW.KCTP.WW.Y.0020.171213T2300Z-171214T1300Z/
/O.CON.KCTP.LE.W.0001.000000T0000Z-171213T1800Z/
Warren-
Including the city of Warren
405 AM EST Wed Dec 13 2017

...LAKE EFFECT SNOW WARNING REMAINS IN EFFECT UNTIL 1 PM EST THIS
AFTERNOON...
...WINTER WEATHER ADVISORY IN EFFECT FROM 6 PM THIS EVENING TO
8 AM EST THURSDAY...

* WHAT...Bands of heavy lake effect snow will diminish during the
  midday hours today, then additional snow will occur late today
  and tonight. Plan on difficult travel conditions. Additional
  snow accumulations of 2 to 4 inches expected this morning, and
  another 2 to 4 inches of snow will follow for late today and 
  tonight.

* WHERE...Warren County.

* WHEN...For the Lake Effect Snow Warning, until 1 PM EST this 
  afternoon. For the Winter Weather Advisory, from 6 PM this 
  evening to 8 AM EST Thursday.

* ADDITIONAL DETAILS...Be prepared for significant reductions in 
  visibility at times.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

The Pennsylvania Department of Transportation and Pennsylvania
Turnpike Commission strongly encourage motorists to heed all
travel restrictions and delay unnecessary travel. Visit
www.511pa.com for the latest travel, roadway and traffic
conditions.

$$

PAZ017-131800-
/O.NEW.KCTP.WW.Y.0020.171213T2300Z-171214T1300Z/
/O.CON.KCTP.WW.Y.0019.000000T0000Z-171213T1800Z/
Clearfield-
Including the cities of DuBois and Clearfield
405 AM EST Wed Dec 13 2017

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 1 PM EST THIS
AFTERNOON...
...WINTER WEATHER ADVISORY IN EFFECT FROM 6 PM THIS EVENING TO
8 AM EST THURSDAY...

* WHAT...Bands of snow showers will meander across the county this
  morning. Additional snow will spread in from the west for late
  today and tonight. Plan on slippery road conditions. Additional
  snow accumulations of an inch or two is expected this morning,
  followed by another 2 to 4 inches of snow late today and
  tonight. 

* WHERE...Clearfield County.

* WHEN...For the Winter Weather Advisory, until 1 PM EST this 
  afternoon. For the Winter Weather Advisory, from 6 PM this 
  evening to 8 AM EST Thursday.

* ADDITIONAL DETAILS...Be prepared for reduced visibilities at 
  times.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

The Pennsylvania Department of Transportation and Pennsylvania
Turnpike Commission remind motorists to adjust speeds based on
driving conditions as winter weather impacts Pennsylvania
roadways. Visit www.511pa.com for the latest travel, roadway and
traffic conditions.


$$

PAZ005-010-131800-
/O.NEW.KCTP.WW.Y.0020.171213T2300Z-171214T1300Z/
/O.CON.KCTP.WW.Y.0019.000000T0000Z-171213T1800Z/
McKean-Elk-
Including the cities of Bradford, St. Marys, and Ridgway
405 AM EST Wed Dec 13 2017

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 1 PM EST THIS
AFTERNOON...
...WINTER WEATHER ADVISORY IN EFFECT FROM 6 PM THIS EVENING TO
8 AM EST THURSDAY...

* WHAT...Bands of lake effect snow are occurring, and will 
  dissipate during the midday hours today. Additional snow will 
  spread in from the west late today and continue tonight. Plan on
  slippery road conditions. Additional snow accumulations of up 
  to two inches are expected this morning. Another 2 to 3 inches 
  of snow is likely late today and tonight.

* WHERE...McKean and Elk Counties.

* WHEN...For the Winter Weather Advisory, until 1 PM EST this 
  afternoon. For the Winter Weather Advisory, from 6 PM this 
  evening to 8 AM EST Thursday.

* ADDITIONAL DETAILS...Be prepared for reduced visibilities at 
  times.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

The Pennsylvania Department of Transportation and Pennsylvania
Turnpike Commission remind motorists to adjust speeds based on
driving conditions as winter weather impacts Pennsylvania
roadways. Visit www.511pa.com for the latest travel, roadway and
traffic conditions.

$$

PAZ024-033-131800-
/O.NEW.KCTP.WW.Y.0020.171213T2300Z-171214T1300Z/
Cambria-Somerset-
Including the cities of Johnstown and Somerset
405 AM EST Wed Dec 13 2017

...WINTER WEATHER ADVISORY IN EFFECT FROM 6 PM THIS EVENING TO
8 AM EST THURSDAY...

* WHAT...Snow expected. Plan on slippery road conditions. Snow 
  accumulations of 3 to 4 inches are expected.

* WHERE...Cambria and Somerset Counties.

* WHEN...From 6 PM this evening to 8 AM EST Thursday.

* ADDITIONAL DETAILS...Be prepared for reduced visibilities at 
  times.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

The Pennsylvania Department of Transportation and Pennsylvania
Turnpike Commission remind motorists to adjust speeds based on
driving conditions as winter weather impacts Pennsylvania
roadways. Visit www.511pa.com for the latest travel, roadway and
traffic conditions.

$$

Lambert/RXR
749 
WWUS41 KCTP 131808
WSWCTP

URGENT - WINTER WEATHER MESSAGE
National Weather Service State College PA
108 PM EST Wed Dec 13 2017

...A fast moving Alberta Clipper storm system will bring a 
widespread light to moderate snowfall to the region overnight...


PAZ004-140215-
/O.EXP.KCTP.LE.W.0001.000000T0000Z-171213T1800Z/
/O.CON.KCTP.WW.Y.0020.171213T2300Z-171214T1300Z/
Warren-
Including the city of Warren
108 PM EST Wed Dec 13 2017

...LAKE EFFECT SNOW WARNING WILL EXPIRE AT 1 PM EST THIS
AFTERNOON...

...THE NEW WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 6 PM 
THIS EVENING TO 8 AM EST THURSDAY...


* WHAT...Snow expected. Additional snow accumulations of 3 to 5 
  inches are expected.

* WHERE...Warren County.

* WHEN...Winter Weather Advisory, from 6 PM this evening to 8 AM 
  EST Thursday.

* ADDITIONAL DETAILS...Be prepared for reduced visibilities and
  poor road conditions.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

The Pennsylvania Department of Transportation and Pennsylvania
Turnpike Commission remind motorists to adjust speeds based on
driving conditions as winter weather impacts Pennsylvania
roadways. Visit www.511pa.com for the latest travel, roadway and
traffic conditions.

$$

PAZ017-140215-
/O.EXP.KCTP.WW.Y.0019.000000T0000Z-171213T1800Z/
/O.CON.KCTP.WW.Y.0020.171213T2300Z-171214T1300Z/
Clearfield-
Including the cities of DuBois and Clearfield
108 PM EST Wed Dec 13 2017

...WINTER WEATHER ADVISORY WILL EXPIRE AT 1 PM EST THIS
AFTERNOON...

...THE NEW WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 6 PM 
THIS EVENING TO 8 AM EST THURSDAY...


* WHAT...Snow expected. Additional snow accumulations of 3 to 5 
  inches are expected.

* WHERE...Clearfield County.

* WHEN...Winter Weather Advisory, from 6 PM this evening to 8 AM 
  EST Thursday.

* ADDITIONAL DETAILS...Be prepared for reduced visibilities and
  poor road conditions.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

The Pennsylvania Department of Transportation and Pennsylvania
Turnpike Commission remind motorists to adjust speeds based on
driving conditions as winter weather impacts Pennsylvania
roadways. Visit www.511pa.com for the latest travel, roadway and
traffic conditions.

$$

PAZ005-010-140215-
/O.EXP.KCTP.WW.Y.0019.000000T0000Z-171213T1800Z/
/O.CON.KCTP.WW.Y.0020.171213T2300Z-171214T1300Z/
McKean-Elk-
Including the cities of Bradford, St. Marys, and Ridgway
108 PM EST Wed Dec 13 2017

...WINTER WEATHER ADVISORY WILL EXPIRE AT 1 PM EST THIS
AFTERNOON...

...THE NEW WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 6 PM 
THIS EVENING TO 8 AM EST THURSDAY...


* WHAT...Snow expected. Additional snow accumulations of 3 to 5 
  inches are expected.

* WHERE...McKean and Elk Counties.

* WHEN...Winter Weather Advisory, from 6 PM this evening to 8 AM 
  EST Thursday.

* ADDITIONAL DETAILS...Be prepared for reduced visibilities and
  poor road conditions.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

The Pennsylvania Department of Transportation and Pennsylvania
Turnpike Commission remind motorists to adjust speeds based on
driving conditions as winter weather impacts Pennsylvania
roadways. Visit www.511pa.com for the latest travel, roadway and
traffic conditions.

$$

PAZ006-011-012-018-019-025>028-034-037-041-042-045-046-049>053-
056>059-140215-
/O.EXB.KCTP.WW.Y.0020.171214T0000Z-171214T1300Z/
Potter-Cameron-Northern Clinton-Northern Centre-Southern Centre-
Blair-Huntingdon-Mifflin-Juniata-Bedford-Tioga-Northern Lycoming-
Sullivan-Southern Clinton-Southern Lycoming-Union-Snyder-Montour-
Northumberland-Columbia-Perry-Dauphin-Schuylkill-Lebanon-
Including the cities of Coudersport, Emporium, Renovo, 
Philipsburg, State College, Altoona, Huntingdon, Mount Union, 
Lewistown, Mifflintown, Bedford, Mansfield, Wellsboro, Trout Run,
Laporte, Lock Haven, Williamsport, Lewisburg, Selinsgrove, 
Danville, Sunbury, Shamokin, Bloomsburg, Berwick, Newport, 
Harrisburg, Hershey, Pottsville, and Lebanon
108 PM EST Wed Dec 13 2017

...WINTER WEATHER ADVISORY IN EFFECT FROM 7 PM THIS EVENING TO
8 AM EST THURSDAY...

* WHAT...Snow expected. Total snow accumulations of 2 to 4 inches,
  with localized amounts up to 6 inches possible.

* WHERE...Much of central Pennsylvania.

* WHEN...From 7 PM this evening to 8 AM EST Thursday.

* ADDITIONAL DETAILS...Be prepared for reduced visibilities and
  poor road conditions.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

The Pennsylvania Department of Transportation and Pennsylvania
Turnpike Commission remind motorists to adjust speeds based on
driving conditions as winter weather impacts Pennsylvania
roadways. Visit www.511pa.com for the latest travel, roadway and
traffic conditions.

$$

PAZ024-033-140215-
/O.CON.KCTP.WW.Y.0020.171213T2300Z-171214T1300Z/
Cambria-Somerset-
Including the cities of Johnstown and Somerset
108 PM EST Wed Dec 13 2017

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 6 PM THIS
EVENING TO 8 AM EST THURSDAY...

* WHAT...Snow expected. Total snow accumulations of 3 to 6 inches
  are expected.

* WHERE...Cambria and Somerset Counties.

* WHEN...From 6 PM this evening to 8 AM EST Thursday.

* ADDITIONAL DETAILS...Be prepared for reduced visibilities and
  poor road conditions.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

The Pennsylvania Department of Transportation and Pennsylvania
Turnpike Commission remind motorists to adjust speeds based on
driving conditions as winter weather impacts Pennsylvania
roadways. Visit www.511pa.com for the latest travel, roadway and
traffic conditions.

$$

What forecasters said that day

The local office's own words before this lake effect snow 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 lake effect snow warning went out at Dec 11, 7:11 AM EST, 4 hours 51 minutes earlier.

Area forecast discussion, Dec 11, 7:11 AM EST, 4 hours 51 minutes before
Area Forecast Discussion
National Weather Service State College PA
711 AM EST Mon Dec 11 2017

.SYNOPSIS...
An alberta clipper will track just north of Pennsylvania
tonight, with a trailing arctic cold front sweeping through the
area Tuesday. A deep upper level trough will remain over the
eastern conus through the rest of this week with another weak
clipper likely affecting the area Thursday. The upper trough
will likely lift out by next weekend.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A moisture-starved shortwave is moving through central Pa early
this morning, accompanied by a few snow showers/flurries over
the northern mountains. The shortwave will be passing east of
the area by 12Z. However, will maintain mention of a few
lingering snow showers across the northwest mountains until late
morning in association with a dying cold front sagging south
from the Grt Lks.

For most of central Pa, expect a dry and slightly milder
Monday, as ridging briefly works into the region. Downsloping
subsidence should result in mostly sunny skies east of the
mountains, while stratocu lingers beneath subsidence inversion
over the northwest mountains. By late in the day, expect
increasing mid and high level cloudiness to arrive ahead of
clipper over the Grt Lks. Model soundings are well mixed to at
least 900mb, where temps of -4C to -6C should translate to max
temps from around 30F over the northwest mountains, to near 40F
across the Lower Susq Valley.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
All model guidance tracks clipper north of Pa tonight, which
should keep the most substantial snow north of Pa. However,
blend of latest guidance still supports a period of light
overrunning snow across northern Pa, with accums generally in
the 1-3 inch range. An examination of model omega/temperature
time sections indicates bulk of lift occurring tonight will be
well beneath the DGZ, indicating snow/water ratios not much
above 10 to 1.

The coldest air of the season is forecast to arrive behind
trailing arctic cold front Tuesday with more lake effect snow
lasting through midweek. Between light clipper snow tonight and
Tue-Wed lake effect, WPC graphics indicate about a 50 pct chance
of exceeding winter storm criteria across the snowbelt of
Warren County, so have issued a wint storm watch up there.
Further east, all model guidance indicating limited potential of
reaching warning criteria. However, model blended qpf supports
a long duration advisory over Elk/Mckean counties.

Still some concern about snow squalls accompanying cold front
passage between 12Z-18Z Tuesday. However, lower tropospheric
lapse rates look less impressive than would be expected for a
significant snow squall event and 00Z model CAPES are
nonexistent until front reaches the Lower Susq Valley, where
boundary layer temps appear borderline for shra vs shsn and
surface temps are likely to be near 40F.

Gusty wnw winds will develop Tuesday behind the cold front with
bufkit soundings supporting frequent gusts of 30kts+ by late
in the day.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
Model soundings suggest wind advisory criteria is possible
early Wed, as large scale subsidence and pressure fall/rise
couplet moves through. Have added blowing/drifting to the
forecast, where sig snow is expected over the northwest
mountains. Base of upper trough and coldest air will be over the
region Wed, with temps likely not reaching 20F over the
Allegheny Plateau and only reaching the upper 20s across the
LSV.

Lake effect snow is likely to abate late Wed, as weak surface
ridge builds in from the Grt Lks. Med range guidance indicates
another clipper is likely to affect the area Thursday with
another potential light snowfall. After that, ECENS and GEFS
both indicate upper trough will lift out, resulting in a marked
warm up next weekend. Latest EC ensemble MOS guidance indicating
temps returning to near or slightly above climo by next
weekend.

&&

.AVIATION /12Z MONDAY THROUGH FRIDAY/...
Lake flow will keep snow showers over the KBFD terminal off and
on through the mid morning hours. Restrictions there will remain
IFR through about 15z, then improve to MVFR. MVFR cigs will
persist at KJST into the early afternoon, and brief MVFR cigs
will be poss mid morning in parts of the central mountains. Mainly
VFR conditions are forecast elsewhere, with a scattered to
broken deck between 5000 and 12000 feet. Winds will be westerly
at 5 to 10 knots.

An alberta clipper will track just north of Pennsylvania
tonight, with a trailing arctic cold front sweeping through the
area Tuesday. Light snow will begin to impact NW mountains after
midnight, and spread into the NW half around 10-14z Tues. The
snow will be accompanied by cig/vsby reductions - again
primarily over the NW half of CWA. Some concern about snow
squalls accompanying cold front passage between 12Z-18Z Tuesday.
Then gusty WNW winds develop with frequent gusts of 30kts+ by
late in the day.

Outlook...

Late tonight and Tuesday...Periods of light snow - mainly NW
half. Widespread MVFR likely, with periods of IFR and brief
LIFR cigs and vsbys NW.

Wed...Snow showers with IFR NW Mtns. Sct snow showers with MVFR
NW half. Otherwise VFR.

Thu-Fri...Sct snow showers. Reductions west.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory from 7 PM this evening to 4 PM EST
Wednesday for PAZ005-010.
Winter Storm Watch from this evening through Wednesday
afternoon for PAZ004.

&&

SYNOPSIS...Fitzgerald
NEAR TERM...Fitzgerald
SHORT TERM...Fitzgerald
LONG TERM...Fitzgerald
AVIATION...RXR
Hazardous weather outlook, Dec 11, 6:50 AM EST, 5 hours 12 minutes before
Hazardous Weather Outlook
National Weather Service State College PA
650 AM EST Mon Dec 11 2017

PAZ019-024>028-033>036-045-046-049>053-056>059-063>066-121200-
Southern Centre-Cambria-Blair-Huntingdon-Mifflin-Juniata-Somerset-
Bedford-Fulton-Franklin-Southern Clinton-Southern Lycoming-Union-
Snyder-Montour-Northumberland-Columbia-Perry-Dauphin-Schuylkill-
Lebanon-Cumberland-Adams-York-Lancaster-
650 AM EST Mon Dec 11 2017

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...Tuesday through Sunday.

Strong, gusty winds will develop over the area Tuesday night into
Wednesday, as the coldest air of the season moves into the area.
The wind gusts could potentially be strong enough to down tree limbs
and result in scattered power outages.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

PAZ004-121200-
Warren-
650 AM EST Mon Dec 11 2017

...WINTER STORM WATCH IN EFFECT FROM THIS EVENING THROUGH WEDNESDAY
AFTERNOON...

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 Storm Watch.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday.

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

   Winter Storm Watch.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

PAZ005-010-121200-
McKean-Elk-
650 AM EST Mon Dec 11 2017

...WINTER WEATHER ADVISORY IN EFFECT FROM 7 PM THIS EVENING TO 4 PM
EST WEDNESDAY...

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...Tuesday through Sunday.

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...

Spotter activation is not expected at this time.

PAZ006-011-012-017-018-037-041-042-121200-
Potter-Cameron-Northern Clinton-Clearfield-Northern Centre-Tioga-
Northern Lycoming-Sullivan-
650 AM EST Mon Dec 11 2017

This Hazardous Weather Outlook is for central Pennsylvania.

.DAY ONE...Today and Tonight.

Light snow will fall over the area tonight into early Tuesday
morning. Accumulations only be between 1 and 2 inches in most
places, but could still cause slippery roads Tuesday morning.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday.

Strong, gusty winds will develop over the area Tuesday night into
Wednesday, as the coldest air of the season moves into the area.
The wind gusts could potentially be strong enough to down tree limbs
and result in scattered power outages.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

The office that day

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

IssuedProductOfficeCountiesLasted
Dec 11, 4:25 AM ESTWinter Weather AdvisoryCTPCambria, Clearfield, Elk, McKean, Somerset57 hr

Nearby

Lake Effect Snow Warnings in Pennsylvania, 2017Every lake effect snow warning in 2017

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.