Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 11, NWS State College, PA

April 1, 1998Lancaster County, York County, Pennsylvania

NWS State College, PA issued this severe thunderstorm warning at Apr 1, 1998, 7:44 PM EST for Lancaster County, York County, Pennsylvania. It was in force for 61 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
Apr 1, 1998, 7:44 PM EST (00:44 UTC)
Expired
Apr 1, 1998, 8:45 PM EST
In force
61 min
Issued by
NWS State College, PA
Area
Whole counties

Counties Lancaster County, PA, York County, PA

The radar

The Sterling radar (KLWX), 141 km from the middle of the area, began a volume at 00:44 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Apr 1, 7:15 PM ESTTornado WatchSPC5 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 00:00Z, 0.7 hours before the alert went out and 139 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, Washington/Dulle, VA at 00:00Z on 1998-04-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1170 joules per kilogram.LCLEL10008507005003002001001 km2 km3 km6 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Washington/Dulle, VA at 00:00Z on 1998-04-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 104 square meters per square second.1939587897Sfc1 km3 km6 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
1170 J/kg
Mixed-layer CIN
-6 J/kg
Mixed-layer LCL
817 m above ground
0-6 km bulk shear
80 kt
0-1 km storm-relative helicity
104 m²/s²
0-3 km storm-relative helicity
192 m²/s²
Significant tornado parameter
0.6
Supercell composite
3.7

Open this sounding in Storm Lab

The text

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

242 
WUUS01 KCTP 020046 RRA
SVRCTP
PAC071-133-020145-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE STATE COLLEGE PA
744 PM EST WED APR 1 1998
 
THE NATIONAL WEATHER SERVICE IN STATE COLLEGE HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  845 PM EST
FOR PEOPLE IN THE FOLLOWING LOCATIONS...S...
 
IN  PENNSYLVANIA
 
   ...LANCASTER COUNTY...EASTERN YORK COUNTY
 
NATIONAL WEATHER SERVICE DOPPLER RADAR AT 742 PM EST SHOWED A SEVERE
THUNDERSTORM OVER EASTERN YORK COUNTY...FROM NEAR WRIGHTSVILLE SOUTH TO
RED LION.
 
THE STORM WAS MOVING TO THE NORTHEAST AT 40 MPH.
 
CITIES AND TOWNS IN THE PATH OF THIS STORM ARE LANCASTER...MILLERSVILLE
AND SAFE HARBOR.
 
A TORNADO WATCH IS ALSO IN EFFECT FOR THE WARNED AREA.  REMEMBER
SEVERE THUNDERSTORMS CAN AND OCCASIONALLY DO PRODUCE TORNADOES
WITH LITTLE OR NO ADVANCE WARNING.  REMAIN CALM BUT BE ALERT TO
RAPIDLY CHANGING WEATHER CONDITIONS.
 
LAMBERT/JUNG

What forecasters said that day

The local office's own words before this severe thunderstorm 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 severe thunderstorm warning went out at Apr 1, 2:45 PM EST, 4 hours 59 minutes earlier.

Area forecast discussion, Apr 1, 2:45 PM EST, 4 hours 59 minutes before
CENTRAL PENNSYLVANIA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
245 PM EST WED APR 1 1998

...SUGGESTIONS...

...SET OF WRKZONES SENT TO EACH OFFICE...

...DISCUSSION...

FRONT MOVING THRU CTRL PA AT MID DAY. CONVECTION FIRED FROM JUST
EAST OF CTP DOWN TO MD BORDER. MINI BOW ECHO TYPE RETURNS SHOWED
SOME DECENT SHEAR ON DOPPLER DOWN OVER FRANKLIN AND ADAMS COUNTY.
LOWER SUSQ STILL RIPE FOR BEST SHOT AT SR WITH FRONT EXPECTED TO
SLOW AND BECOME WAVY...ALLOWING DEWPOINTS TO POOL AND CREATE AT
LEAST MARGINAL INSTABILITY.

WHAT SEEMS CERTAIN IS THE RECENT LATE MARCH RECORD BREAKING WARMTH
HAS COME TO A GRINDING HALT COURTESY OF THE PRESENT RESPECTABLE
ANAFRONT SLIDING SLOWLY EAST. WHAT FOLLOWS FOR NEXT DAY OR SO IS
CYCLONIC FLOW ALOFT WITH POTENTIAL FOR COLD ADVECTION STRATO-CU AND
SPOTTY PRECIP IN NORMALLY FAVORED UPSLOPE NWRN LOCATIONS. REST OF
REGION WILL LIKELY SEE NORMAL TRANSITION FROM M-CLDY NW TO AT LEAST
P-SUNNY SE WITH RETURN TO MORE SEASONAL READINGS.

FRONT A TAD SLOWER THAN EXPECTED YESTERDAY BUT NOT SIGNIFICANTLY SO.
STILL TIMING LAG PLACES XTRM SE PA UNDER THE GUN FOR SEVERE THIS PM
AS DEWPOINTS RISE ALLOWING STABILITY TO ERODE. MODELS SUGGEST FRONT
SLOWS UNDER INCREASING PARALLEL UPPER FLOW WHICH FURTHER SUGGESTS
WAVES MAY DEVELOP ALONG THE FRONT AS IT EDGES THRU ERN PA. THIS WUD
BE A CONCERN AS ANY MESOSCALE BACKING OF FLOW WUD INCREASE POTENTIAL
HELICITY IN LOW LEVELS IN THE VICINITY OF THE BOUNDARY OR ANY WAVE
THAT MAY FORM. LIMITING FACTOR WUD BE CLOUDCOVER KEEPING LID ON
INSTABILITY. VISUALS SHOW PRETTY HEAVY CLOUD SHIELD ALL THE WAY
TO CAROLINAS. CONTRIBUTING FACTOR IS MID LEVEL DRYING WHICH WATER
VAPOR IMAGERY SHOWS IS SURGING INTO WRN PA NOW. WITH THIS SLATED TO
OVERRUN MOIST LOW LEVELS LATER TODAY...AND IF BREAKS MANAGE TO FORM
IN PREFRONTAL SWLY FLOW...THIS AREA CUD BECOME VERY INTERESTING.

FOR REST OF AREA IN THE BIG PICTURE...CLEARING BEHIND FRONTAL SURGE
HAS A FEW LIGHT SHOWERS EMBEDDED...BUT THESE TOO SHUD DIE WITH LOSS
OF HEATING. THINK BEST CHC OF POPS NEXT DAY OR SO WILL BE OVER AREAS
OF NRN MTNS WHERE BEST MOISTURE ASSOC WITH SHEARING UPPER SHORTWAVE
GETS CLOSEST. ALSO MAY SEE SHOWERS OVER LAURELS AS WEST FLOW ACTS AS
UPSLOPE.

AVN TAKES NEXT SYSTEM AND SUGGESTS PRECIP INVADING FROM SOUTHWEST BY
LATER FRIDAY. I DISCARDED THIS AS PER NGM/ETA SLOWER SOLUTIONS.
STILL...LOOKS POTENTIALLY COLD AND INCLEMENT FOR WEEKEND AS CUT OFF
SLIDES OFF TO OUR SOUTH. SNOW MAY YET ENTER THE PICTURE AGAIN BY SAT
IF AVN VERIFIES.

LA CORTE

In the hours before

Special weather statement, Apr 1, 7:18 PM EST, 26 minutes before
PAZ064>066-020515-

SPECIAL WEATHER STATEMENT - TORNADO WATCH
NATIONAL WEATHER SERVICE STATE COLLEGE PA
718 PM EST WED APR 1 1998

...THE NATIONAL WEATHER SERVICE HAS ISSUED A TORNADO WATCH
FOR PORTIONS OF THE LOWER SUSQUEHANNA VALLEY UNTIL MIDNIGHT
TONIGHT...

THE TORNADO WATCH INCLUDES THE FOLLOWING COUNTIES:

ADAMS... YORK AND LANCASTER.

...FORECAST DETAILS...

A COLD FRONT SWEEPING ACROSS THE LOWER SUSQUEHANNA VALLEY THIS
EVENING IS TRIGGERING THUNDERSTORMS ACROSS THE REGION...MAINLY SOUTH
OF THE TURNPIKE.  SOME OF THE THUNDERSTORMS THIS EVENING MAY BECOME
SEVERE...AND COULD SPAWN A TORNADO.

REMEMBER... A TORNADO WATCH MEANS THAT TORNADOES ARE POSSIBLE IN
AND NEAR THE WATCH AREA. LARGE HAIL... DAMAGING WINDS... AND
TORRENTIAL RAINFALL MAY ALSO OCCUR. BE READY TO SEEK A PLACE OF
SAFETY IF A WARNING IS ISSUED FOR YOUR AREA.

DO NOT USE YOUR CAR TO OUTRUN A TORNADO. CARS ARE EASILY TOSSED
AROUND BY TORNADIC WINDS. IF YOU ARE CAUGHT IN THE PATH OF A
TORNADO... LEAVE THE CAR AND GO TO A STRONG BUILDING. IF NO
STRUCTURE IS NEARBY...SEEK SAFETY IN A DITCH OR LOW SPOT. BE
MINDFUL OF RISING WATERS.

STAY TUNED TO NOAA WEATHER RADIO OR YOUR LOCAL RADIO OR TV STATION
FOR LATER STATEMENTS OR WARNINGS CONCERNING THIS SEVERE WEATHER
SITUATION.

JUNG
Special weather statement, Apr 1, 7:18 PM EST, 26 minutes before
PAZ064>066-020515-

SPECIAL WEATHER STATEMENT - TORNADO WATCH
NATIONAL WEATHER SERVICE STATE COLLEGE PA
718 PM EST WED APR 1 1998

...THE NATIONAL WEATHER SERVICE HAS ISSUED A TORNADO WATCH
FOR PORTIONS OF THE LOWER SUSQUEHANNA VALLEY UNTIL MIDNIGHT
TONIGHT...

THE TORNADO WATCH INCLUDES THE FOLLOWING COUNTIES:

ADAMS... YORK AND LANCASTER.

...FORECAST DETAILS...

A COLD FRONT SWEEPING ACROSS THE LOWER SUSQUEHANNA VALLEY THIS
EVENING IS TRIGGERING THUNDERSTORMS ACROSS THE REGION...MAINLY SOUTH
OF THE TURNPIKE.  SOME OF THE THUNDERSTORMS THIS EVENING MAY BECOME
SEVERE...AND COULD SPAWN A TORNADO.

REMEMBER... A TORNADO WATCH MEANS THAT TORNADOES ARE POSSIBLE IN
AND NEAR THE WATCH AREA. LARGE HAIL... DAMAGING WINDS... AND
TORRENTIAL RAINFALL MAY ALSO OCCUR. BE READY TO SEEK A PLACE OF
SAFETY IF A WARNING IS ISSUED FOR YOUR AREA.

DO NOT USE YOUR CAR TO OUTRUN A TORNADO. CARS ARE EASILY TOSSED
AROUND BY TORNADIC WINDS. IF YOU ARE CAUGHT IN THE PATH OF A
TORNADO... LEAVE THE CAR AND GO TO A STRONG BUILDING. IF NO
STRUCTURE IS NEARBY...SEEK SAFETY IN A DITCH OR LOW SPOT. BE
MINDFUL OF RISING WATERS.

STAY TUNED TO NOAA WEATHER RADIO OR YOUR LOCAL RADIO OR TV STATION
FOR LATER STATEMENTS OR WARNINGS CONCERNING THIS SEVERE WEATHER
SITUATION.

JUNG

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 1998Every severe thunderstorm warning in 1998

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.