Alert archive / Pennsylvania / Flash Flood Warnings in 2021
Flash Flood Warning 28, NWS State College, PA
NWS State College, PA issued this flash flood warning at Sep 1, 2021, 4:24 PM EDT for Adams County, York County, Pennsylvania. It was in force for 4 hr. 2 reports came from inside the area while it was in force.
The area
The outline as issued, with what was reported inside it.
The facts
- Issued
- Sep 1, 2021, 4:24 PM EDT (20:24 UTC)
- Expired
- Sep 1, 2021, 8:30 PM EDT
- In force
- 4 hr
- Issued by
- NWS State College, PA
- Area
- Storm-based polygon
- Emergency
- Flash flood emergency
- Damage threat
- Catastrophic
- Flood severity
- None
Counties Adams County, PA, York County, PA
The radar
The Sterling radar (KLWX), 127 km from the middle of the area, began a volume at 20:28 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
| Time | Report | Where | Remark |
|---|---|---|---|
| Sep 1, 5:30 PM EDT | FLASH FLOOD | 1 Sse York, PA | SIGNIFICANT FLOODING ALONG TYLER RUN CREEK IN THE VICINITY OF YORK COLLEGE. |
| Sep 1, 6:10 PM EDT | FLASH FLOOD | 1 Ne York, PA | INTERSTATE 83 IS CLOSED DUE TO FLOODING OF MILL CREEK BETWEEN ROUTE 30 AND MARKET STREET (ROUTE 462). |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
The nearest sounding before it
Washington/Dulle, VA (KIAD), launched 12:00Z, 8.4 hours before the alert went out and 127 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
- 558 J/kg
- Mixed-layer CIN
- -21 J/kg
- Mixed-layer LCL
- 575 m above ground
- 0-6 km bulk shear
- 48 kt
- 0-1 km storm-relative helicity
- 122 m²/s²
- 0-3 km storm-relative helicity
- 223 m²/s²
- Significant tornado parameter
- 0.4
- Supercell composite
- 2.6
The text
As transmitted.
407
WGUS51 KCTP 012024
FFWCTP
PAC001-133-012230-
/O.NEW.KCTP.FF.W.0028.210901T2024Z-210901T2230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service State College PA
424 PM EDT Wed Sep 1 2021
...FLASH FLOOD EMERGENCY FOR SOUTHERN ADAMS COUNTY NORTHEAST INTO
YORK COUNTY...
The National Weather Service in State College has issued a
* Flash Flood Warning for...
Adams County in south central Pennsylvania...
York County in south central Pennsylvania...
* Until 630 PM EDT.
* At 424 PM EDT, Doppler radar and automated rain gauges indicated
thunderstorms producing heavy rain across the warned area.
Additional rainfall amounts of 1 to 3 inches are possible in the
warned area. Flash flooding is already occurring. If you do not
have to travel, please stay off the roads.
This is a FLASH FLOOD EMERGENCY for Southern Adams County
northeast into York County. This is a PARTICULARLY DANGEROUS
SITUATION. SEEK HIGHER GROUND NOW!
HAZARD...Life threatening flash flooding. Thunderstorms
producing flash flooding.
SOURCE...Radar and automated gauges.
IMPACT...This is a PARTICULARLY DANGEROUS SITUATION. SEEK
HIGHER GROUND NOW! Life threatening flash flooding of
low water crossings, small creeks and streams, urban
areas, highways, streets and underpasses.
* Some locations that will experience flash flooding include...
York, Hanover, Weigelstown, Gettysburg, Parkville, Red Lion, Spry,
Dallastown, Hampton, Shiloh, East York, Stonybrook-Wilshire, West
York, Littlestown, Carroll Valley, Shrewsbury, Codorus, Grantley,
Valley Green and Tyler Run-Queens Gate.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Move to higher ground now! This is an extremely dangerous and
life-threatening situation. Do not attempt to travel unless you are
fleeing an area subject to flooding or under an evacuation order.
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
&&
LAT...LON 3972 7742 3976 7741 3995 7724 4016 7695
4017 7691 4017 7692 4022 7683 4020 7683
4018 7675 4013 7674 4006 7666 4005 7657
4005 7653 3996 7649 3991 7639 3986 7637
3972 7647
FLASH FLOOD...RADAR AND GAUGE INDICATED
FLASH FLOOD DAMAGE THREAT...CATASTROPHIC
$$
CR2 follow-up statements
581
WGUS71 KCTP 012223
FFSCTP
Flash Flood Statement
National Weather Service State College PA
623 PM EDT Wed Sep 1 2021
PAC133-012233-
/O.CAN.KCTP.FF.W.0028.000000T0000Z-210901T2230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
York PA-
623 PM EDT Wed Sep 1 2021
...FLASH FLOOD WARNING IS CANCELLED FOR YORK COUNTY...
Flooding is no longer expected to pose a threat. Please continue to
heed remaining road closures.
A Flash Flood Watch remains in effect until 800 AM EDT Thursday for
a portion of central Pennsylvania.
LAT...LON 3972 7742 3976 7741 3995 7724 4005 7710
4003 7707 4001 7702 3994 7697 3993 7697
3992 7697 3990 7698 3989 7698 3988 7697
3987 7696 3986 7696 3985 7698 3983 7699
3983 7700 3972 7700
$$
PAC001-012230-
/O.CON.KCTP.FF.W.0028.000000T0000Z-210901T2230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Adams PA-
623 PM EDT Wed Sep 1 2021
...FLASH FLOOD EMERGENCY FOR SOUTHERN ADAMS COUNTY NORTHEAST INTO
YORK COUNTY...
...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 630 PM EDT THIS
EVENING FOR ADAMS COUNTY...
At 623 PM EDT, Doppler radar and automated rain gauges indicated
thunderstorms producing heavy rain across the warned area.
Additional rainfall amounts of 1 to 3 inches are possible in the
warned area. Flash flooding is already occurring.
This is a FLASH FLOOD EMERGENCY for Southern Adams County northeast
into York County. This is a PARTICULARLY DANGEROUS SITUATION. SEEK
HIGHER GROUND NOW!
HAZARD...Life threatening flash flooding. Thunderstorms producing
flash flooding.
SOURCE...Radar and automated gauges.
IMPACT...This is a PARTICULARLY DANGEROUS SITUATION. SEEK HIGHER
GROUND NOW! Life threatening flash flooding of low water
crossings, small creeks and streams, urban areas,
highways, streets and underpasses.
Some locations that will experience flash flooding include...
Hanover, Gettysburg, Hampton, Littlestown, Carroll Valley,
McSherrystown, Lake Meade, Bonneauville, New Oxford, East Berlin,
Lake Heritage, Biglerville, Abbottstown, York Springs,
Heidlersburg, Hunterstown, Fairfield, Two Taverns, Gettysburg
National Military Park and Gettysburg College.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Move to higher ground now! This is an extremely dangerous and
life-threatening situation. Do not attempt to travel unless you are
fleeing an area subject to flooding or under an evacuation order.
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
&&
LAT...LON 3972 7742 3976 7741 3995 7724 4005 7710
4003 7707 4001 7702 3994 7697 3993 7697
3992 7697 3990 7698 3989 7698 3988 7697
3987 7696 3986 7696 3985 7698 3983 7699
3983 7700 3972 7700
FLASH FLOOD...RADAR AND GAUGE INDICATED
FLASH FLOOD DAMAGE THREAT...CATASTROPHIC
$$
Colbert865
WGUS51 KCTP 012226
FFWCTP
PAC001-020030-
/O.EXT.KCTP.FF.W.0028.000000T0000Z-210902T0030Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service State College PA
626 PM EDT Wed Sep 1 2021
...FLASH FLOOD EMERGENCY FOR SOUTHERN ADAMS COUNTY...
The National Weather Service in State College has extended the
* Flash Flood Warning for...
Adams County in south central Pennsylvania...
* Until 830 PM EDT.
* At 626 PM EDT, emergency management reported ongoing flooding from
heavy rain in Adams County. Between 5 and 7 inches of rain have
fallen. Additional rainfall amounts up to 1 inch is possible in
the warned area. Flash flooding is already occurring.
This is a FLASH FLOOD EMERGENCY for Southern Adams County. This is
a PARTICULARLY DANGEROUS SITUATION. SEEK HIGHER GROUND NOW!
HAZARD...Life threatening flash flooding. Thunderstorms
producing flash flooding.
SOURCE...Emergency management reported.
IMPACT...This is a PARTICULARLY DANGEROUS SITUATION. SEEK
HIGHER GROUND NOW! Life threatening flash flooding of
low water crossings, small creeks and streams, urban
areas, highways, streets and underpasses.
* Some locations that will experience flash flooding include...
Hanover, Gettysburg, Hampton, Littlestown, Carroll Valley,
McSherrystown, Lake Meade, Bonneauville, New Oxford, East Berlin,
Lake Heritage, Biglerville, Abbottstown, York Springs,
Heidlersburg, Hunterstown, Fairfield, Two Taverns, Gettysburg
National Military Park and Gettysburg College.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Move to higher ground now! This is an extremely dangerous and
life-threatening situation. Do not attempt to travel unless you are
fleeing an area subject to flooding or under an evacuation order.
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
Be especially cautious at night when it is harder to recognize the
dangers of flooding.
&&
LAT...LON 3972 7742 3976 7741 3995 7724 4005 7710
4003 7707 4001 7702 3994 7697 3993 7697
3992 7697 3990 7698 3989 7698 3988 7697
3987 7696 3986 7696 3985 7698 3983 7699
3983 7700 3972 7700
FLASH FLOOD...OBSERVED
FLASH FLOOD DAMAGE THREAT...CATASTROPHIC
$$
ColbertThe office that day
Everything else NWS State College, PA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 1, 8:54 AM EDT | Flash Flood Warning | CTP | Bedford, Blair, Cambria, Centre, Clearfield, Fulton and 3 more | 8 hr |
| Sep 1, 9:37 AM EDT | Flash Flood Warning | CTP | Cambria, Clearfield, Somerset | 6 hr |
| Sep 1, 9:45 AM EDT | Areal Flood Advisory | CTP | Adams, Columbia, Cumberland, Dauphin, Franklin, Juniata and 10 more | 2 hr |
| Sep 1, 11:04 AM EDT | River Flood Warning | CTP | Snyder, Union | 17 hr |
| Sep 1, 11:04 AM EDT | River Flood Warning | CTP | Cambria | 17 hr |
| Sep 1, 11:04 AM EDT | River Flood Warning | CTP | Huntingdon | 23 hr |
| Sep 1, 11:04 AM EDT | River Flood Warning | CTP | Juniata, Mifflin | 20 hr |
| Sep 1, 11:04 AM EDT | River Flood Warning | CTP | Bedford, Huntingdon | 30 hr |
| Sep 1, 11:04 AM EDT | River Flood Warning | CTP | Dauphin | 55 hr |
| Sep 1, 12:04 PM EDT | Flash Flood Warning | CTP | Adams, Columbia, Cumberland, Dauphin, Franklin, Juniata and 10 more | 6 hr |
| Sep 1, 1:09 PM EDT | Flash Flood Warning | CTP | Cambria | 5 hr |
| Sep 1, 2:07 PM EDT | Severe Thunderstorm Warning | CTP | Adams | 53 min |
| Sep 1, 2:28 PM EDT | Severe Thunderstorm Warning | CTP | York | 77 min |
| Sep 1, 3:05 PM EDT | Tornado Warning | CTP | York | 23 min |
| Sep 1, 3:25 PM EDT | Severe Thunderstorm Warning | CTP | Lancaster, York | 35 min |
| Sep 1, 3:34 PM EDT | Areal Flood Warning | CTP | Cambria, Clearfield, Somerset | 6 hr |
| Sep 1, 4:21 PM EDT | Severe Thunderstorm Warning | CTP | Lancaster | 39 min |
| Sep 1, 4:40 PM EDT | Areal Flood Warning | CTP | Bedford, Blair, Cambria, Centre, Clearfield, Franklin and 4 more | 6 hr |
| Sep 1, 5:41 PM EDT | Areal Flood Warning | CTP | Adams, Centre, Columbia, Cumberland, Dauphin, Franklin and 15 more | 14 hr |
Nearby
Flash Flood Warnings in Pennsylvania, 2021Every flash flood warning 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.