Alert archive / Pennsylvania / Special Weather Statements in 2021

Special Weather Statement, NWS State College, PA

August 18, 2021Centre County, Pennsylvania

NWS State College, PA issued this special weather statement at Aug 18, 2021, 2:29 PM EDT for Centre County, Pennsylvania. It was in force for 31 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: Aug 18, 2021, 2:29 PM EDT (18:29 UTC)
Expired: Aug 18, 2021, 3:00 PM EDT
In force: 31 min
Issued by: NWS State College, PA
Hail: 0.00 in
Wind: 55

County Centre County, PA

The radar

The State College radar (KCCX), 21 km from the middle of the area, began a volume at 18:31 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

Pittsburgh, PA (KPIT), launched 12:00Z, 6.5 hours before the alert went out and 206 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: 109 J/kg
Mixed-layer CIN: -40 J/kg
Mixed-layer LCL: 684 m above ground
0-6 km bulk shear: 30 kt
0-1 km storm-relative helicity: 132 m²/s²
0-3 km storm-relative helicity: 165 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.1

Open this sounding in Storm Lab

The text

As transmitted.

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What forecasters said that day

The local office's own words before this special weather statement 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 special weather statement went out at Aug 18, 1:57 PM EDT, 32 minutes earlier.

Area forecast discussion, Aug 18, 1:57 PM EDT, 32 minutes before

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      <div class="status" id="status">Temporary Notice</div>
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        The site you requested is temporarily down for maintenance or an unexpected outage.
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Hazardous weather outlook, Aug 18, 11:39 AM EDT, 2 hours 50 minutes before

Hazardous Weather Outlook
National Weather Service State College PA
1139 AM EDT Wed Aug 18 2021

PAZ004>006-037-191545-
Warren-McKean-Potter-Tioga-
1139 AM EDT Wed Aug 18 2021

...FLASH FLOOD WATCH IN EFFECT THROUGH LATE TONIGHT...

This Hazardous Weather Outlook is for central Pennsylvania.

.DAY ONE...This afternoon and tonight.

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

   Flash Flood Watch.

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

The probability for widespread hazardous weather is low.

.SPOTTER INFORMATION STATEMENT...

Spotters are encouraged to report significant hazardous weather.

PAZ010>012-017>019-024>028-033>036-041-042-045-046-049>053-056>059-
063>066-191545-
Elk-Cameron-Northern Clinton-Clearfield-Northern Centre-
Southern Centre-Cambria-Blair-Huntingdon-Mifflin-Juniata-Somerset-
Bedford-Fulton-Franklin-Northern Lycoming-Sullivan-Southern Clinton-
Southern Lycoming-Union-Snyder-Montour-Northumberland-Columbia-Perry-
Dauphin-Schuylkill-Lebanon-Cumberland-Adams-York-Lancaster-
1139 AM EDT Wed Aug 18 2021

...FLASH FLOOD WATCH IN EFFECT THROUGH LATE TONIGHT...
...TORNADO WATCH 447 IN EFFECT UNTIL 8 PM EDT THIS EVENING...

This Hazardous Weather Outlook is for central Pennsylvania.

.DAY ONE...This afternoon and tonight.

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

   Tornado Watch.
   Flash Flood Watch.

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

The probability for widespread hazardous weather is low.

.SPOTTER INFORMATION STATEMENT...

Spotters are encouraged to report significant hazardous weather.

In the hours before

Special weather statement, Aug 18, 1:01 PM EDT, 1 hour 28 minutes before

Special Weather Statement
National Weather Service State College PA
101 PM EDT Wed Aug 18 2021

PAZ018-019-025-026-181745-
Northern Centre PA-Blair PA-Huntingdon PA-Southern Centre PA-
101 PM EDT Wed Aug 18 2021

...Strong thunderstorms will impact portions of northwestern
Huntingdon, southwestern Centre and northeastern Blair Counties
through 145 PM EDT...

At 100 PM EDT, Doppler radar was tracking strong thunderstorms along
a line extending from near Bald Eagle to near Trough Creek State
Park. Movement was north at 25 mph.

HAZARD...Wind gusts of 50 to 55 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects.

Locations impacted include...
Huntingdon, Tyrone, Bald Eagle, Warriors Mark, Williamsburg, Port
Matilda, Sandy Ridge, Spruce Creek, Birmingham, Franklinville,
Raystown Dam, Shy Beaver, Trough Creek State Park, Entriken,
McConnellstown, Petersburg, Alexandria, Marklesburg and Juniata
College.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

Very heavy rainfall is also occurring with these storms and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.

These storms may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

A Tornado Watch remains in effect until 800 PM EDT for central
Pennsylvania.

&&

LAT...LON 4092 7810 4048 7791 4035 7803 4029 7821
      4069 7825 4081 7828
TIME...MOT...LOC 1700Z 191DEG 20KT 4070 7821 4039 7811

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...55 MPH

Colbert

Special weather statement, Aug 18, 1:15 PM EDT, 1 hour 14 minutes before

Special Weather Statement
National Weather Service State College PA
115 PM EDT Wed Aug 18 2021

PAZ027-028-181745-
Juniata PA-Mifflin PA-
115 PM EDT Wed Aug 18 2021

...A strong thunderstorm will impact portions of central Mifflin and
northwestern Juniata Counties through 145 PM EDT...

At 114 PM EDT, Doppler radar was tracking a strong thunderstorm near
Spruce Hill, moving north at 50 mph.

HAZARD...Wind gusts of 50 to 55 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects.

Locations impacted include...
Lewistown, Burnham, Belleville, Milroy, Highland Park, Honey Grove,
Yeagertown, Spruce Hill, Strodes Mills, Reedsville, Juniata Terrace,
Alfarata, Belltown, Walnut, Seven Mountains, Reeds Gap State Park,
Mifflintown, Port Royal, Mifflin and Maitland.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

A Tornado Watch remains in effect until 800 PM EDT for central and
south central Pennsylvania.

&&

LAT...LON 4046 7774 4067 7770 4068 7768 4068 7770
      4071 7769 4073 7768 4079 7752 4065 7729
      4043 7747 4040 7754 4038 7753 4037 7756
TIME...MOT...LOC 1714Z 188DEG 42KT 4047 7752

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...55 MPH

Colbert

Local storm report, Aug 18, 1:28 PM EDT, 1 hour 1 minute before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
128 PM EDT WED AUG 18 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0115 PM     FLASH FLOOD      WILLIAMSBURG            40.46N 78.20W
08/18/2021                   BLAIR              PA   911 CALL CENTER

            NUMEROUS FLOODED ROADS IN AND AROUND
            WILLIAMSBURG.

&&

Special weather statement, Aug 18, 2:00 PM EDT, 29 minutes before

Special Weather Statement
National Weather Service State College PA
200 PM EDT Wed Aug 18 2021

PAZ028-050-056-181830-
Perry PA-Juniata PA-Snyder PA-
200 PM EDT Wed Aug 18 2021

...A strong thunderstorm will impact portions of northeastern
Juniata, western Snyder and northeastern Perry Counties through 230
PM EDT...

At 159 PM EDT, Doppler radar was tracking a strong thunderstorm near
Mcalisterville, moving north at 50 mph.

HAZARD...Wind gusts up to 50 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects.

Locations impacted include...
Middleburg, Mcalisterville, McClure, Penns Creek, Beaver Springs,
Richfield, Mount Pleasant Mills, Paxtonville, Troxelville,
Snyder-Middleswart State Park, Beavertown, Thompsontown, Millerstown
and East Salem.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

Very heavy rainfall is also occurring with this storm and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.

A Tornado Watch remains in effect until 800 PM EDT for central and
south central Pennsylvania.

&&

LAT...LON 4052 7733 4069 7732 4069 7729 4070 7732
      4082 7732 4087 7706 4086 7702 4088 7699
      4050 7709
TIME...MOT...LOC 1759Z 186DEG 41KT 4060 7720

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...50 MPH

Jurewicz

Special weather statement, Aug 18, 2:26 PM EDT, 3 minutes before

Special Weather Statement
National Weather Service State College PA
226 PM EDT Wed Aug 18 2021

PAZ056-063-181900-
Perry PA-Cumberland PA-
226 PM EDT Wed Aug 18 2021

...A strong thunderstorm will impact portions of north central
Cumberland and eastern Perry Counties through 300 PM EDT...

At 226 PM EDT, Doppler radar was tracking a strong thunderstorm over
Plainfield, moving northeast at 50 mph.

HAZARD...Wind gusts up to 50 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects.

Locations impacted include...
Carlisle, Plainfield, Schlusser, Boiling Springs, Mount Holly
Springs, Newport, Duncannon, Newville, New Bloomfield, New Kingstown,
New Buffalo, Bloserville, Wertzville, Carlisle Springs, Shermansdale,
Liverpool, Millerstown, Landisburg and Penn State Dickinson School Of
Law.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

Very heavy rainfall is also occurring with this storm and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

A Tornado Watch remains in effect until 800 PM EDT for south central
and central Pennsylvania.

&&

LAT...LON 4017 7741 4055 7720 4056 7717 4059 7717
      4061 7701 4063 7695 4059 7696 4057 7699
      4052 7698 4047 7695 4042 7702 4039 7703
      4037 7702 4035 7699 4009 7720
TIME...MOT...LOC 1826Z 206DEG 43KT 4021 7726

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...50 MPH

Jurewicz

Special weather statement, Aug 18, 2:29 PM EDT, 0 minutes before

Special Weather Statement
National Weather Service State College PA
229 PM EDT Wed Aug 18 2021

PAZ018-019-181900-
Northern Centre PA-Southern Centre PA-
229 PM EDT Wed Aug 18 2021

...A strong thunderstorm will impact portions of central Centre
County through 300 PM EDT...

At 229 PM EDT, Doppler radar was tracking a strong thunderstorm over
Milesburg, moving north at 40 mph.

HAZARD...Wind gusts of 50 to 55 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects.

Locations impacted include...
State College, Bellefonte, Park Forest Village, Boalsburg, Pleasant
Gap, Lemont, Zion, Houserville, Milesburg, Snow Shoe, Blanchard,
Clarence, Julian, Bald Eagle State Park, Howard, Beech Creek,
Unionville, Pennsylvania State University and University Park
Airport.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

A Tornado Watch remains in effect until 800 PM EDT for central and
north central Pennsylvania.

&&

LAT...LON 4107 7757 4078 7776 4080 7794 4112 7799
TIME...MOT...LOC 1829Z 188DEG 33KT 4094 7776

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...55 MPH

Colbert

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 18, 9:50 AM EDT	Special Weather Statement	CTP	Bedford	55 min
Aug 18, 10:25 AM EDT	Areal Flood Advisory	CTP	Bedford	3 hr
Aug 18, 10:32 AM EDT	Severe Thunderstorm Warning	CTP	Bedford, Blair	43 min
Aug 18, 10:53 AM EDT	Special Weather Statement	CTP	Cambria	37 min
Aug 18, 10:57 AM EDT	Special Weather Statement	CTP	Bedford	18 min
Aug 18, 11:15 AM EDT	Special Weather Statement	CTP	Blair, Cambria	30 min
Aug 18, 11:33 AM EDT	Areal Flood Advisory	CTP	Blair, Cambria	3 hr
Aug 18, 12:04 PM EDT	Areal Flood Advisory	CTP	Bedford	2 hr
Aug 18, 12:11 PM EDT	Special Weather Statement	CTP	Blair	34 min
Aug 18, 12:26 PM EDT	Special Weather Statement	CTP	Schuylkill	34 min
Aug 18, 12:35 PM EDT	Flash Flood Warning Considerable damage threat	CTP	Bedford, Blair, Huntingdon	3 hr
Aug 18, 12:39 PM EDT	Special Weather Statement	CTP	Cumberland	36 min
Aug 18, 12:54 PM EDT	Severe Thunderstorm Warning	CTP	Cumberland, Perry	36 min
Aug 18, 1:01 PM EDT	Special Weather Statement	CTP	Huntingdon	44 min
Aug 18, 1:15 PM EDT	Special Weather Statement	CTP	Juniata, Mifflin	30 min
Aug 18, 1:31 PM EDT	Severe Thunderstorm Warning	CTP	Juniata, Perry	44 min
Aug 18, 1:37 PM EDT	Flash Flood Warning Considerable damage threat	CTP	Blair, Centre, Huntingdon	82 min
Aug 18, 2:00 PM EDT	Special Weather Statement	CTP	Snyder	30 min
Aug 18, 2:02 PM EDT	Tornado Warning	CTP	Centre, Huntingdon	28 min
Aug 18, 2:12 PM EDT	Severe Thunderstorm Warning	CTP	Centre, Clinton	33 min
Aug 18, 2:26 PM EDT	Special Weather Statement	CTP	Cumberland, Perry	34 min
Aug 18, 2:36 PM EDT	Severe Thunderstorm Warning	CTP	Cumberland, Perry	39 min
Aug 18, 3:03 PM EDT	Special Weather Statement	CTP	Cumberland	42 min
Aug 18, 3:10 PM EDT	Tornado Warning	CTP	Adams, York	40 min
Aug 18, 3:17 PM EDT	Areal Flood Warning	CTP	Bedford, Blair, Huntingdon	118 min
Aug 18, 3:36 PM EDT	Severe Thunderstorm Warning	CTP	Cumberland, Dauphin, Lancaster, York	24 min
Aug 18, 3:56 PM EDT	Severe Thunderstorm Warning	CTP	Dauphin, Juniata, Northumberland, Perry, Snyder	34 min
Aug 18, 4:03 PM EDT	Special Weather Statement	CTP	Dauphin	42 min
Aug 18, 4:05 PM EDT	Severe Thunderstorm Warning	CTP	Franklin, Fulton	40 min
Aug 18, 4:30 PM EDT	Areal Flood Advisory	CTP	Juniata, Perry, Snyder	4 hr
Aug 18, 4:30 PM EDT	Special Weather Statement	CTP	Snyder	30 min
Aug 18, 4:39 PM EDT	Severe Thunderstorm Warning	CTP	Franklin	36 min
Aug 18, 4:42 PM EDT	Areal Flood Advisory	CTP	Fulton, Huntingdon	2 hr
Aug 18, 4:48 PM EDT	Areal Flood Advisory	CTP	Cameron, Clinton, Lycoming, Potter, Tioga	5 hr
Aug 18, 5:10 PM EDT	Severe Thunderstorm Warning	CTP	Adams, Cumberland, Franklin, Perry, York	35 min
Aug 18, 5:18 PM EDT	Severe Thunderstorm Warning	CTP	Juniata, Mifflin	45 min
Aug 18, 5:31 PM EDT	Severe Thunderstorm Warning	CTP	Dauphin	74 min
Aug 18, 5:35 PM EDT	Special Weather Statement	CTP	Lancaster	25 min
Aug 18, 5:35 PM EDT	Severe Thunderstorm Warning	CTP	Adams	40 min
Aug 18, 5:38 PM EDT	Severe Thunderstorm Warning	CTP	Adams, Cumberland, York	37 min
Aug 18, 6:13 PM EDT	Severe Thunderstorm Warning	CTP	Adams, Cumberland, Dauphin, Lancaster, Perry, York	47 min
Aug 18, 6:37 PM EDT	Areal Flood Advisory	CTP	Adams, Cumberland, Franklin, York	2 hr
Aug 18, 6:47 PM EDT	Severe Thunderstorm Warning	CTP	Adams, Dauphin, Lancaster, Lebanon, Schuylkill, York	43 min
Aug 18, 6:56 PM EDT	Special Weather Statement	CTP	Schuylkill	19 min
Aug 18, 7:23 PM EDT	Areal Flood Advisory	CTP	Columbia, Sullivan	2 hr
Aug 18, 7:30 PM EDT	Severe Thunderstorm Warning	CTP	Lancaster, York	45 min
Aug 18, 7:37 PM EDT	Flash Flood Warning Considerable damage threat	CTP	Schuylkill	2 hr
Aug 18, 7:40 PM EDT	Flash Flood Warning	CTP	Dauphin, Lancaster, York	3 hr

Nearby

Special Weather Statements in Pennsylvania, 2021 Every special weather statement in 2021

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.