Alert archive / Pennsylvania / Flash Flood Warnings in 1997

Flash Flood Warning 12, NWS State College, PA

June 18, 1997Lancaster County, Pennsylvania

NWS State College, PA issued this flash flood warning at Jun 18, 1997, 8:38 PM EDT for Lancaster County, Pennsylvania. It was in force for 3 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Jun 18, 1997, 8:38 PM EDT (00:38 UTC)
Expired
Jun 18, 1997, 11:45 PM EDT
In force
3 hr
Issued by
NWS State College, PA
Area
Whole counties

County Lancaster County, PA

The radar

The Dover AFB radar (KDOX), 152 km from the middle of the area, began a volume at 00:38 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

Wallops Is Stn, VA (KWAL), launched 00:00Z, 0.6 hours before the alert went out and 246 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, Wallops Is Stn, VA at 00:00Z on 1997-06-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1609 joules per kilogram.LCLLFCEL10008507005003002001001 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, Wallops Is Stn, VA at 00:00Z on 1997-06-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 56 square meters per square second.19395878Sfc1 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
1609 J/kg
Mixed-layer CIN
-79 J/kg
Mixed-layer LCL
1132 m above ground
0-6 km bulk shear
23 kt
0-1 km storm-relative helicity
56 m²/s²
0-3 km storm-relative helicity
75 m²/s²
Significant tornado parameter
0.0
Supercell composite
2.2

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
TTAA00 KCTP 190038
FFWCTP
PAC071-190345-
 
BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE STATE COLLEGE PA
838 PM EDT WED JUN 18 1997
 
THE NATIONAL WEATHER SERVICE IN STATE COLLEGE HAS ISSUED A
FLASH FLOOD WARNING EFFECTIVE UNTIL 1145 PM EDT
FOR PEOPLE IN THE FOLLOWING LOCATIONS......
 
IN  PENNSYLVANIA
 
   ...LANCASTER COUNTY
 
AT 830 PM STATE COLLEGE DOPPLER RADAR SHOWED A LINE OF SLOW MOVING
THUNDERSTORMS OVER NORTHERN LANCASTER COUNTY...NORTH OF RTE 30.
 
RADAR ESTIMATES BETWEEN 1 AND 1.5 INCHES OF RAIN HAS FALLEN SINCE 730
PM OVER NORTHERN LANCASTER COUNTY. RAIN GAGE REPORTS FROM ELM ALSO
SHOWED MORE THAN 1 INCH OF RAIN HAS FALLEN.
 
THUNDERSTORMS WITH VERY HEAVY RAIN WILL CONTINUE OVER NORTHERN LANCASTER
COUNTY THROUGH AROUND 9 PM. EXPECT FLOODING OF POOR DRAINAGE AND LOW
LYING AREAS INCLUDING AREAS IN THE VICINITY OF MANHEIM... EPHRATA
AND MY JOY.
 
BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZ&E
THE DANGERS OF FLOODS AND FLASH FLOODS.  IF FLASH FLOODING IS
OBSERVED...ACT QUICKLY.  MOVE UP TO ESCAPE FLOOD WATERS.  DO
NOT STAY IN AREAS SUBJECT TO FLOODING WHEN WATER BEGINS RISING.
 
LA CORTE/NICOSIA
 
&

What forecasters said that day

The local office's own words before this flash flood 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 flash flood warning went out at Jun 18, 1:28 PM EDT, 7 hours 10 minutes earlier.

Area forecast discussion, Jun 18, 1:28 PM EDT, 7 hours 10 minutes before
CENTRAL PENNSYLVANIA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
120 PM EDT WED JUN 18 1997

...DISCUSSION...

WON'T SPEND A LOT OF TIME HERE AS DEVELOPING CONVECTION NEEDS MOST
ATTENTION THIS AFTERNOON.

CLOUD COVER BREAKING UP RAPIDLY IN WARM SECTOR WITH MESO ANALYSIS
AND DIAGNOSTICS SHOWING RAPIDLY DESTABILIZING AIRMASS. MESO DATA
FROM PSU SHOWS STRONG MOISTURE CONVERGENCE OVER LAUREL HIGHLANDS
WHERE TEMPERATURES ARE CLIMBING QUICKLY. DEWPOINTS IN MID TO UPPER
60S SHOULD PROVIDE PLENTY OF FUEL AS INCREASING DYNAMICS SWING
ACROSS REGION LATER TODAY AND THIS EVENING.

BOUNDARY EXTENDS ACROSS CTRL PA ASSOC WITH WEAK BACK-DOOR COOL
FRONT WHICH SETTLED SOUTH ACROSS REGION LAST 24HRS. LOW LEVEL
HELICITY VALUES ABOUT THIS FEATURE ARE APPROACHING THE MILDLY
IMPRESSIVE RANGE WITH BRN'S OFF THE MASSAGED 12Z SOUNDING
SUPPORTIVE OF SUPERCEL DEVELOPMENT. LOW LEVEL JET IN THE RANGE OF
30KTS OR SO IS ALREADY EVIDENT ON PIT/CTP VWP'S. UPPER LEVEL JET
STREAK PROGGED TO APPROACH REGION DURING THE AFTERNOON AND EVENING.
LOWER BRANCH OF AGEOSTROPHIC TRANSVERSE CIRCULATION IN THE JET EXIT
WILL PROVIDE ADDITIONAL SLY COMPONENT TO LOW LEVEL FLOW WHICH WILL
ONLY HELP SUPPORT THIS FEATURE. BOTTOM LINE IS THAT IT LOOKS LIKE
A BUSY DAY SETTING UP FOR REGIONAL OFFICES.

AGREE IN WINDING DOWN ACTIVITY OVERNIGHT WITH FOG LIKELY IN SOME
LOCATIONS. AM STILL LEERY ABOUT THU. DEWPOINTS DON'T DROP ALL THAT
MUCH DURING THE DAY AND MODELS SHOW WEAK SECONDARY UPPER SHORTWAVE
SLIDING ACROSS DURG THE AFTERNOON. WE ARE APPROACHING THE TIME OF
YEAR WHERE THUNDER POTENTIAL NEEDS TO BE ASSESSED ALMOST DAILY. NEW
ETA TAKES AREA OF 30+ K INDICES JUST SOUTH OF THE BORDER DURG MAX
HEATING.

LA CORTE

In the hours before

Special weather statement, Jun 18, 3:07 PM EDT, 5 hours 31 minutes before
PAZ034-025-024-011-018-019-017-012-045-010-035-026-028-041-046-
005-027-006-033-037-004-190030-

SPECIAL WEATHER STATEMENT...CORRECTED
NATIONAL WEATHER SERVICE STATE COLLEGE PA
233 PM EDT WED JUN 18 1997

...SEVERE THUNDERSTORM WATCH...

THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM WATCH FOR
MUCH OF WESTERN PENNSYLVANIA. THE WATCH IS VALID UNTIL 8PM THIS EVENING
AND INCLUDES THE FOLLOWING COUNTIES:

WARREN... MCKEAN... ELK... CAMERON.. POTTER... TIOGA... CLINTON...
CLEARFIELD... CENTRE... LYCOMING... CAMBRIA... BLAIR... SOMERSET
... HUNTINGDON... FULTON... JUNIATA... MIFFLIN AND BEDFORD.

A COLD FRONT WILL CONTINUE MOVING ACROSS CENTRAL PENNSYLVANIA THIS
AFTERNOON AND THIS EVENING. WARM HUMID AIR IN PLACE OVER THE REGION
WILL CREATE CONDITIONS RIPE FOR LOCALLY SEVERE THUNDERSTORMS.
THUNDERSTORMS WILL INCREASE IN COVERAGE AND INTENSITY AS THE AFTERNOON
PROGRESSES. SOME OF THESE STORMS WILL CONTAIN LARGE HAIL ANDL
STRONG DAMAGING WINDS.

...CORRECTED TO ADD CENTRE COUNTY TO WATCH...

LA CORTE
Special weather statement, Jun 18, 5:20 PM EDT, 3 hours 18 minutes before
PAZ004>006-010>012-017>019-024>028-033>037-041-042-045-046-049>053-
056>059-063>066-190300-

SPECIAL WEATHER STATEMENT...SEVERE THUNDERSTORM WATCH
NATIONAL WEATHER SERVICE STATE COLLEGE PA
520 PM EDT WED JUN 18 1997

...SEVERE THUNDERSTORM WATCH...

THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM WATCH
FOR MUCH OF EASTERN PENNSYLVANIA VALID UNTIL 11 PM.

THE SEVERE THUNDERSTORM WATCH INCLUDES THE FOLLOWING COUNTIES:

TIOGA... LYCOMING... SULLIVAN... UNION... SNYDER...
NORTHUMBERLAND... MONTOUR... COLUMBIA... CENTRE... HUNTINGDON...
BEDFORD... FULTON... FRANKLIN... MIFFLIN... JUNIATA...
SCHUYLKILL... PERRY... DAUPHIN... LEBANON... CUMBERLAND... ADAMS...
YORK AND LANCASTER.

A COLD FRONT WILL CONTINUE MOVING ACROSS CENTRAL PENNSYLVANIA THIS
EVENING. WARM HUMID AIR IN PLACE OVER THE REGION WILL SUPPORT THE
POTENTIAL FOR THUNDERSTORMS...SOME WHICH WILL CAUSE LARGE HAIL AND
STRONG DAMAGING WINDS.

THE COLD FRONT WILL SETTLE SOUTH OF THE AREA LATER TONIGHT BRINGING
AN END TO THE THREAT OF SEVERE STORMS.

IN ADDITION...A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL
10 PM FOR MUCH OF THE REST OF WESTERN PENNSYLVANIA. THE WATCH
INCLUDES THE FOLLOWING COUNTIES:

WARREN... MCKEAN... ELK... CAMERON.. POTTER... CLEARFIELD...
CAMBRIA... BLAIR... SOMERSET...

LA CORTE
Special weather statement, Jun 18, 5:22 PM EDT, 3 hours 16 minutes before
PAZ004>006-010>012-017>019-024>028-033>037-041-042-045-046-049>053-
056>059-063>066-190300-

SPECIAL WEATHER STATEMENT...SEVERE THUNDERSTORM WATCH
NATIONAL WEATHER SERVICE STATE COLLEGE PA
520 PM EDT WED JUN 18 1997

...SEVERE THUNDERSTORM WATCH...

THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM WATCH
FOR MUCH OF EASTERN PENNSYLVANIA VALID UNTIL 11 PM.

THE SEVERE THUNDERSTORM WATCH INCLUDES THE FOLLOWING COUNTIES:

TIOGA... LYCOMING... SULLIVAN... UNION... SNYDER...
NORTHUMBERLAND... MONTOUR... COLUMBIA... CENTRE... HUNTINGDON...
BEDFORD... FULTON... FRANKLIN... MIFFLIN... JUNIATA...
SCHUYLKILL... PERRY... DAUPHIN... LEBANON... CUMBERLAND... ADAMS...
YORK AND LANCASTER.

A COLD FRONT WILL CONTINUE MOVING ACROSS CENTRAL PENNSYLVANIA THIS
EVENING. WARM HUMID AIR IN PLACE OVER THE REGION WILL SUPPORT THE
POTENTIAL FOR THUNDERSTORMS...SOME WHICH WILL CAUSE LARGE HAIL AND
STRONG DAMAGING WINDS.

THE COLD FRONT WILL SETTLE SOUTH OF THE AREA LATER TONIGHT BRINGING
AN END TO THE THREAT OF SEVERE STORMS.

IN ADDITION...A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL
10 PM FOR MUCH OF THE REST OF WESTERN PENNSYLVANIA. THE WATCH
INCLUDES THE FOLLOWING COUNTIES\:

WARREN... MCKEAN... ELK... CAMERON.. POTTER... CLEARFIELD...
CAMBRIA... BLAIR... SOMERSET...

LA CORTE
Special weather statement, Jun 18, 7:00 PM EDT, 1 hour 38 minutes before
PAZ004>006-010>012-017>019-024>028-033>037-041-042-045-046-049>053-
056>059-063>066-190300-

SPECIAL WEATHER STATEMENT...SEVERE THUNDERSTORM WATCH CANCELED
NATIONAL WEATHER SERVICE STATE COLLEGE PA
7 PM EDT WED JUN 18 1997

...SEVERE THUNDERSTORM WATCH CANCELED FOR PARTS OF THE NORTHERN
MOUNTAINS...

THE NATIONAL WEATHER SERVICE HAS CANCELED THE SEVERE THUNDERSTORM
WATCH FOR PARTS OF THE NORTHERN MOUNTAINS.

THE WATCH HAS BEEN CANCELED FOR MCKEAN... POTTER... ELK AND CAMERON
COUNTIES.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 8PM FOR
NORTHERN CLINTON...BLAIR AND NORTHERN CENTRE COUNTIES.

IN ADDITION A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 11
PM FOR THE FOLLOWING COUNTIES:

TIOGA... LYCOMING... SULLIVAN... UNION... SNYDER...
NORTHUMBERLAND... MONTOUR... COLUMBIA... SOUTH CENTRE...
HUNTINGDON... BEDFORD... FULTON... FRANKLIN... MIFFLIN...
JUNIATA... SCHUYLKILL... PERRY... DAUPHIN... LEBANON...
CUMBERLAND... ADAMS... YORK AND LANCASTER.

IN ADDITION...A FLASH FLOOD WATCH REMAINS IN EFFECT UNTIL 10 PM FOR
CLEARFIELD... NORTHERN CENTRE... CAMBRIA... SOMERSET... AND BLAIR
COUNTIES.

A COLD FRONT MOVING THROUGH THE REGION HAS TRIGGERED WIDESPREAD
SHOWER AND THUNDERSTORM ACTIVITY THIS AFTERNOON AND EVENING. SOME
OF THE THUNDERSTORMS HAVE BEEN REPORTED AS SEVERE WITH LARGE HAIL
AND TORRENTIAL DOWNPOURS.

THE SHOWERS AND THUNDERSTORMS WILL CONTINUE OVER MUCH OF THE AREA
...BEFORE WINDING DOWN LATER THIS EVENING. SOME OF THE STORMS MAY
STILL BECOME SEVERE...CAUSING LARGE HAIL...DAMAGING WINDS AND
FLOODING IN AND NEAR THE WATCH AREAS.

THURSDAY PROMISES TO BE A DRIER AND MUCH MORE SETTLED DAY WITH
SUNSHINE AND PLEASANT TEMPERATURES RETURNING TO THE AREA.

LA CORTE
Special weather statement, Jun 18, 7:01 PM EDT, 1 hour 37 minutes before
PAZ004>006-010>012-017>019-024>028-033>037-041-042-045-046-049>053-
056>059-063>066-190300-

SPECIAL WEATHER STATEMENT...SEVERE THUNDERSTORM WATCH CANCELED
NATIONAL WEATHER SERVICE STATE COLLEGE PA
7 PM EDT WED JUN 18 1997

...SEVERE THUNDERSTORM WATCH CANCELED FOR PARTS OF THE NORTHERN
MOUNTAINS...

THE NATIONAL WEATHER SERVICE HAS CANCELED THE SEVERE THUNDERSTORM
WATCH FOR PARTS OF THE NORTHERN MOUNTAINS.

THE WATCH HAS BEEN CANCELED FOR MCKEAN... POTTER... ELK AND CAMERON
COUNTIES.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 8PM FOR
NORTHERN CLINTON...BLAIR AND NORTHERN CENTRE COUNTIES.

IN ADDITION A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 11
PM FOR THE FOLLOWING COUNTIES:

TIOGA... LYCOMING... SULLIVAN... UNION... SNYDER...
NORTHUMBERLAND... MONTOUR... COLUMBIA... SOUTH CENTRE...
HUNTINGDON... BEDFORD... FULTON... FRANKLIN... MIFFLIN...
JUNIATA... SCHUYLKILL... PERRY... DAUPHIN... LEBANON...
CUMBERLAND... ADAMS... YORK AND LANCASTER.

IN ADDITION...A FLASH FLOOD WATCH REMAINS IN EFFECT UNTIL 10 PM FOR
CLEARFIELD... NORTHERN CENTRE... CAMBRIA... SOMERSET... AND BLAIR
COUNTIES.

A COLD FRONT MOVING THROUGH THE REGION HAS TRIGGERED WIDESPREAD
SHOWER AND THUNDERSTORM ACTIVITY THIS AFTERNOON AND EVENING. SOME
OF THE THUNDERSTORMS HAVE BEEN REPORTED AS SEVERE WITH LARGE HAIL
AND TORRENTIAL DOWNPOURS.

THE SHOWERS AND THUNDERSTORMS WILL CONTINUE OVER MUCH OF THE AREA
...BEFORE WINDING DOWN LATER THIS EVENING. SOME OF THE STORMS MAY
STILL BECOME SEVERE...CAUSING LARGE HAIL...DAMAGING WINDS AND
FLOODING IN AND NEAR THE WATCH AREAS.

THURSDAY PROMISES TO BE A DRIER AND MUCH MORE SETTLED DAY WITH
SUNSHINE AND PLEASANT TEMPERATURES RETURNING TO THE AREA.

LA CORTE
Special weather statement, Jun 18, 7:08 PM EDT, 1 hour 30 minutes before
PAZ004>006-010>012-017>019-024>028-033>037-041-042-045-046-049>053-
056>059-063>066-190300-CORRECTED FOR COUNTIES

SPECIAL WEATHER STATEMENT...SEVERE THUNDERSTORM WATCH CANCELED
NATIONAL WEATHER SERVICE STATE COLLEGE PA
7 PM EDT WED JUN 18 1997

...SEVERE THUNDERSTORM WATCH CANCELED FOR PARTS OF THE NORTHERN
MOUNTAINS...

THE NATIONAL WEATHER SERVICE HAS CANCELED THE SEVERE THUNDERSTORM
WATCH FOR PARTS OF THE NORTHERN MOUNTAINS.

THE WATCH HAS BEEN CANCELED FOR MCKEAN... POTTER... ELK AND CAMERON
COUNTIES.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 8PM FOR
NORTHERN CLINTON...BLAIR AND NORTHERN CENTRE COUNTIES.

IN ADDITION A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 11
PM FOR THE FOLLOWING COUNTIES:

TIOGA... LYCOMING... SULLIVAN... UNION... SNYDER...
NORTHUMBERLAND... MONTOUR... COLUMBIA... SOUTH CENTRE...
HUNTINGDON... BEDFORD... FULTON... FRANKLIN... MIFFLIN...
JUNIATA... SCHUYLKILL... PERRY... DAUPHIN... LEBANON...
CUMBERLAND... ADAMS... YORK AND LANCASTER.

IN ADDITION...A FLASH FLOOD WATCH REMAINS IN EFFECT UNTIL 10 PM FOR
CLEARFIELD... CENTRE... CAMBRIA... SOMERSET... BLAIR... BEDFORD...
HUNTINGDON... MIFFLIN... JUNIATA... FULTON AND FRANKLIN COUNTIES.

A COLD FRONT MOVING THROUGH THE REGION HAS TRIGGERED WIDESPREAD
SHOWER AND THUNDERSTORM ACTIVITY THIS AFTERNOON AND EVENING. SOME
OF THE THUNDERSTORMS HAVE BEEN REPORTED AS SEVERE WITH LARGE HAIL
AND TORRENTIAL DOWNPOURS.

THE SHOWERS AND THUNDERSTORMS WILL CONTINUE OVER MUCH OF THE AREA
...BEFORE WINDING DOWN LATER THIS EVENING. SOME OF THE STORMS MAY
STILL BECOME SEVERE...CAUSING LARGE HAIL...DAMAGING WINDS AND
FLOODING IN AND NEAR THE WATCH AREAS.

THURSDAY PROMISES TO BE A DRIER AND MUCH MORE SETTLED DAY WITH
SUNSHINE AND PLEASANT TEMPERATURES RETURNING TO THE AREA.

LA CORTE

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 18, 8:47 PM EDTSevere Thunderstorm WarningCTPLancaster, York58 min

Nearby

Flash Flood Warnings in Pennsylvania, 1997Every flash flood warning in 1997

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.