Heavy Snow in Pennsylvania, February 22 to 23, 2001

Name: Heavy Snow in Pennsylvania, February 22 to 23, 2001
Start: 2001-02-22T12:30
End: 2001-02-23T12:30
Location: Pennsylvania

February 22 to 23, 2001 · NWS PHI · 10 events in 10 counties and zones

A fast moving low pressure system brought heavy snow to Eastern Pennsylvania on the 22nd. Accumulations averaged between 5 and 10 inches with the highest amounts in the Lehigh Valley and the Poconos.

Where it happened

Every event with a place to put it; 7 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.

Tornadoes
Tropical storms and surge
Floods
Wind
Hail
Winter weather
Heat and drought
Cold
Fire, smoke and dust
Marine and coastal
Other

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The toll

Deaths: 0
Injuries: 0
Property damage: None recorded
Crop damage: None recorded
Events: 10

Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.

What happened

The episode as NWS PHI wrote it up.

A fast moving low pressure system brought heavy snow to Eastern Pennsylvania on the 22nd. Accumulations averaged between 5 and 10 inches with the highest amounts in the Lehigh Valley and the Poconos. Snow began falling during the first half of the afternoon. Cold weather the previous two days made it easy for the snow to accumulate. Roads became slippery quickly as witnesses by Whitemarsh Township (Montgomery County) which reported thirteen accidents within the first half hour that the snow started. In a similar situation to what occurred on the 5th of this month, schools and businesses closed early and created an early rush hour. Numerous accidents occurred, about three times the normal number of crashes. Average commutes took three to four times longer than normal. The heaviest snow fell during the latter half of the afternoon and the first half of the evening. It ended around midnight that night. In Carbon County, the Mansion House Hill road was closed as vehicles became stranded. Many schools were closed the next day (Friday the 23rd). In Northampton County, two tractor trailers became stuck on opposite sides of Pennsylvania State Route 378. Westbound U.S. Route 22 was closed because of an accident around cemetery curve. Cars were abandoned at the bottom of hills as people trudged home from there. Tractor trailers could not make up the hills within Allentown (Lehigh County) also. Around Philadelphia, bus lines were cancelled in the hillier parts of the city and there were dozens of delays at the International Airport. Specific accumulations included in Berks County: 10 inches in Kutztown, 6 inches in Morgantown, 5.5 inches in Hamburg and 5 inches in Reading, in Bucks County: 8 inches in Springtown, 7.4 inches in Doylestown, 7 inches in New Hope and 6 inches in Langhorne, in Carbon County: 10.7 inches in Palmerton, 10.5 inches in Summit Hill, 9 inches in Lehighton, and 7 inches in Jim Thorpe, in Chester County: 8.1 inches in West Chester, 7.5 inches in Valley Forge and 7 inches in Westtown, in Delaware County: 7.5 inches in Media, 7.4 inches in Radnor and 6.7 inches in Clifton, in Lehigh County: 10.5 inches in Schnecksville, 10 inches in New Tripoli, 8.5 inches in Zionsville and 7 to 8 inches in Allentown, in Monroe County: 9.4 inches in Bossardsville, 8.5 inches in East Stroudsburg, 7 inches in Saylorsburg and 6.5 inches in Effort, in Montgomery County: 7.6 inches in King of Prussia, 7 inches in Huntingdon Valley, 6 inches in Palm and Ambler, in Northampton County: 10 inches in Forks, 9 inches in Plainfield and 8.3 inches in Bath and in Philadelphia County: 7 inches at the International Airport and 6.4 inches at the Franklin Institute.The low pressure system responsible for the heavy snow developed along the Red River Valley in the Southern Plains on Wednesday the 21st. By Thursday morning the 22nd, it was located over northern Alabama. It moved quickly offshore and by the morning of the 23rd, it was more than 300 miles east of the Delmarva Peninsula. The quick movement of the low pressure system prevented heavier snow from occurring. But it was compensated by a higher than normal snowfall to water equivalent ratio. In the so-called average snowstorm the ratio of snowfall to water equivalent is usually 10 to 1. For example, 10 inches of snow would melt down to about one inch of water (or rain). In this storm, partially because the air mass over the region was considerably colder than normal, the snowfall to water equivalent ratio was closer to 20 to 1.

What forecasters said that day

The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Philadelphia/Mount Holly wrote its last area forecast discussion before the first event at Feb 22, 10:35 AM EST, 1 hour 55 minutes earlier.

Area forecast discussion, Feb 22, 10:35 AM EST, 1 hour 55 minutes before

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1035 AM EST THU FEB 22 2001

WL UPDATE ZONES TO FRESHEN AND MAKE SOME MINOR ADJUSTMENTS...SPCLY
TO TEMPS WHERE THE RANGE WL BE LOWERED A BIT...BUT LARGE SCALE WRNGS
AND ADVYS LEFT INTACT UNTIL THIS DEVELOPING WASHINGTON/S BIRTHDAY
STORM CAN BE CORRELATED WITH 12Z RUN...SOME OF WHICH WE HAVE SEEN.
NGM AND ETA ARE IN PRETTY GOOD AGREEMENT ON SFC LO TRACK...AND THIS
CAUSES US TO WONDER IF SNOW AMTS WCNTRL AND NRN ZONES NEED TO BE
LOWERED SOMEWHAT....AND PERHAPS EVEN MERCER-MONMOUTH-MIDDLESEX NJ.
EVEN ETA QPF SEEMS TO BE LOWER NOW...ABOUT 0.30 LIQUID HOWVER AS
NOTED FROM PREVIOUS THE RAIN/LIQ EQUIV RATIO SHUD BE FAIRLY HI AND
THIS NEEDS TO BE TAKEN INTO ACCOUNT...AS WAS DONE YDA AS WELL.
HOWEVER WE WILL ASSUME THIS BIAS TWD LWER AMTS NWRN ZONES FOR FUTURE
UPDATES. ALSO...WONDER IF THE STORM WL FINISH SOONER...SPCLY SWRN
ZONES...IN VIEW OF STLT TRENDS. UPDATED WSW WL BE ISSUED ALONG WITH
UPDATED ZONES. NO CHG ON MARINE...SCA KEPT AS WINDS WL BE INCRSG
SOON.

REST AS FROM PREVIOUS...

*********************************************************************

WILL BE ISSUING WINT STORM WRNG FOR PREV WATCH AREA...BUT WILL ADD
A FEW ADTNL CNTRL NJ CTYS OUT OF RESPECT FOR THE DVLPG WRAPARND.
WINT WX ADVSRYS WILL THEN BE ISSUED FOR THE REMAINDER OF OUR CWA.

GENERAL GIST OF THIS FCST WILL BE TO CONT WITH THE AVN MDL WITH THIS
PKG. ETA/S WOES HAVE BEEN DOCUMENTED AND ITS ALRDY (TU HPC) BEEN TOO
WET WITH THIS SYS TO OUR SW. LATEST 06Z MESOETA IS EVER SO SLGTLY
DRIER. THE AVN WHICH WAS NRLY AS WET AS THE ETA ON THE DAY RUN HAS
BCM DRIER ON ITS SUCCESSIVE 18Z AND 00Z RUNS. IT IS ALSO TRENDING A
BIT MORE TO THE SE (WHICH WOULD MAKE SENSE IN THIS ZONAL FLOW). CAN
MDLS ALSO LEAN TWD THE AVN WITH EVEN THE GEM PIVOTING THE HVYST PCPN
FROM S OF THE MASON-DIXON LINE TO THE NJ CST. CONVECTION ACRS TN VLY
IS PRETTY MUCH RACING EWD. CONCERNED THIS MIGHT CUT OFF A BIT WAA
INFLOW FTHR TO THE N WITH FIRST SHOT.

GENERAL UPSHOT THO SYS IS TOO PROGRESSIVE TO BRING VERY HVY SNOW
AND FCSTD MESOSCALE FEATS (PTNL CSI OR EVEN INSTABILITY ITSELF)
ON THE ETA JUST HUG THE JERSEY SHORE. GIVEN ITS WWD BIAS WITH SFC
SYS THIS SHOULD THEN OCR OVR THE ATLC. EVEN THE ETA SEEMS TO BE
KEYING ON OUR DELMARVA FOR THE GREATEST PTNL FOR HVYST PCPN. THAT/S
WHERE ITS W-E ZONE OF STGST WAA/THETA E ADVT OCRS.

AIR MASS CUR OVR THE RGN IS EXTREMELY DRY. SOME OF THE INIT SNOW
BLAST IS GOING TO BE EVAPD INTO THIS DRY AIR. ON THE OTHER HAND...
THE SNOW/LIQUID EQIV RATIO OUGHT TO BE PRETTY HIGH FOR THIS EVENT
ESP N AND W OF PHL. ONE OF THE REASONS FOR NOT MUCH OF A DIF IN
ACCUM FCST FROM OUR CNTRL TO NW ZONES. THE ONLY ZONES WE/LL CONT THE
MNTN OF LIQUID PCPN WILL BE DEZ3/4 AND WILL KNOCK DOWN THE ACCUMS A
TAD THERE. H850 TEMPS AND 1000-850MB THICK GET MARGINAL FROM A
EASTON-DOV-ACY LINE. WOULD EXPECVT EITHER THE INIT EVAP COOLG AND/OR
THE HVY PCPN RATE (STG OMEGAS) TO NEGATE THE PSBLTY OF A MIX IN MOST
PLACES DOWN THERE. ALSO FCST SOUDGS DO NOT SUPPORT SLEET.

LIKE THE JAN 20-21 STORM WOULD EXPECT THIS EVENT TO BRING A COUPLE
OF HOURS OF SHEAR FRIGHT (OR DELIGHT) AS HVY SNOW MOVES QUICKLY THRU
THE RGN. UNFORTUNATELY THIS LOOKS LIKE IT MAY COINCIDE WITH THE EVE
RUSH HOME. GIVEN COLD START TO TDY...THE SNOW SHLD STICK QUITE
EASILY ONCE IT STARTS FALLING. WE/RE NOT GOING TO MOVE UP THE TIMING
BASED ON EVAP PBLMS ALG THE FRONT END...NEVERTHELESS KEYING ON A 6
HR PERIOD FOR MOST OF THE SNOW TO OCR MAINLY AFTN/ERLY ERLY EVE
DELMAR...LT AFTN/ERLY EVE PHL METRO AREA AND ERN PA AND LT AFTN INTO
THE EVE NRN NJ. AFT ABT 01-02Z WHL FLURRIES ARE FCST TO
LINGER...MOST OF THE MSTR IS BLO 700MB.

ETA SUGG MSTR GETS TRAPPED UNDER THE INVERSION IN NW ZONES ON FRI.
ATTM W/O A TRUE SFC HI WE/LL BITE INTO IT. WE/LL MAKE IT
PROGRESSIVELY SUNNIER FTHR TO THE S AND E. THEN FAIR WX FOR FRI NGT
AS HI PRES BUILDS IN. COULD BE PRETTY COLD GIVEN THE FRESH SNOW
PACK. LATEST AVN A BIT SLOR WITH NEXT EVENT. REMOVED MNTN OF PCPN
FOR SAT...BUT ON THE OTHER HAND ADDED THE MNTN OF SOME FZRA IN NWRN
CWA ON SUN BASED ON LATEST THICKNESSES/SFC TEMP FCSTS.

IN GENERAL WE LIKE THE COLDER NGM MOS FOR TDY GIVEN CLDS ARE ALRDY
INCRG TO OUR W. WOULD EXPECT TEMPS AND DEWPTS TO MERGE NOT THE
LATTER RISING TO THE FRMR LIKE THE AVN MAV HAS. WILL TAKE ABT A CAT
OFF FOR THE SNOWPACK ON FRI AND EVEN MORE FRI NGT WITH IDEAL RDTNL
CONDS EXPECTED.

MAR: WE/LL KEEP SCA GOING AS THEY/LL PBLY BE JUST A BRIEF LULL BTWN
SYS.

TU COR COORD EVERONE...HAVE A GOOD NIGHT/DAY.

.PHI...WINTER STORM WARNING PAZ070-071-NJZ012-013>026-DEZALL-
       MDZ008-012-015-019-020 FOR THIS AFTN AND NGT.
       WINTER WX ADVY FOR THIS AFTN AND NGT NJZ001-007>010
       PAZ054-055-060>062/067>069.
       SMALL CRAFT ADVISORY FROM SANDY HOOK NJ TO FENWICK
       ISLAND DE AND FOR DELAWARE BAY.

TFG /

The radar

The national radar mosaic for the moment the first event began.

Open the radar archive at this moment

Event by event

10 heavy snow. Local standard time, as filed.

Heavy Snow, Berks

When: February 22, 12:30 PM EST to February 23, 12:00 PM EST
Where: Berks forecast zone
Reported by: TRAINED SPOTTER
Coordinates: 40.416, -75.926 (the zone’s center; the record gives no point)

Heavy Snow, Chester

When: February 22, 12:30 PM EST to 11:30 PM EST
Where: Chester forecast zone
Reported by: TRAINED SPOTTER

Heavy Snow, Delaware

When: February 22, 12:45 PM EST to February 23, 12:00 PM EST
Where: Delaware forecast zone
Reported by: TRAINED SPOTTER
Coordinates: 39.917, -75.399 (the zone’s center; the record gives no point)

Heavy Snow, Philadelphia

When: February 22, 1:00 PM EST to February 23, 12:00 AM EST
Where: Philadelphia forecast zone
Reported by: TRAINED SPOTTER
Coordinates: 40.008, -75.134 (the zone’s center; the record gives no point)

Heavy Snow, Bucks

When: February 22, 1:30 PM EST to February 23, 12:30 PM EST
Where: Bucks forecast zone
Reported by: TRAINED SPOTTER

Heavy Snow, Montgomery

When: February 22, 1:30 PM EST to February 23, 12:00 AM EST
Where: Montgomery forecast zone
Reported by: TRAINED SPOTTER

Heavy Snow, Carbon

When: February 22, 2:00 PM EST to February 23, 1:00 AM EST
Where: Carbon forecast zone
Reported by: TRAINED SPOTTER
Coordinates: 40.918, -75.709 (the zone’s center; the record gives no point)

Heavy Snow, Lehigh

When: February 22, 2:00 PM EST to February 23, 1:00 AM EST
Where: Lehigh forecast zone
Reported by: TRAINED SPOTTER
Coordinates: 40.613, -75.592 (the zone’s center; the record gives no point)

Heavy Snow, Monroe

When: February 22, 2:00 PM EST to February 23, 2:00 AM EST
Where: Monroe forecast zone
Reported by: TRAINED SPOTTER
Coordinates: 41.058, -75.339 (the zone’s center; the record gives no point)

Heavy Snow, Northampton

When: February 22, 2:00 PM EST to February 23, 1:00 AM EST
Where: Northampton forecast zone
Reported by: TRAINED SPOTTER
Coordinates: 40.754, -75.307 (the zone’s center; the record gives no point)

What these are

Heavy Snow: Snowfall reaching the local warning threshold without the other hazards of a winter storm.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

Every storm in Pennsylvania in 2001 Every state in 2001 This day in weather history Warnings in Pennsylvania, February 2001

Sources

NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 5232057, 5232060, 5232061, 5232066, 5232058, 5232064, 5232059, 5232062, 5232063, 5232065.