National Weather Service United States Department of Commerce

Back-to-Back Pacific Storms to Impact the West Coast; Heavy Snow in the Central Appalachians

Back-to-back powerful Pacific storm systems to impact the Pacific Northwest and northern California through the end of this week with heavy rain, flooding, strong winds, and higher elevation mountain snow. A strong, long-duration atmospheric river will accompany the Pacific storms, bringing excessive rainfall and flash flooding to southwest Oregon and northwest California through the week. Read More >

Overview

A strong area of low pressure moved through the eastern Great Lakes on March 28, 2021, driving a strong cold front towards the mid-Atlantic coast. Unseasonably warm conditions developed ahead of the cold front. As is typical for such environments in the cool season months, only limited instability, up to around 500J/kg of surface based CAPE, developed ahead of the cold front. However, extreme deep layer (0-6km) shear of near 100 kt and strong mechanical lift associated with the cold front combined with the small amount of instability to cause a squall line to develop. This line moved from west to east across the mid-Atlantic during the very late afternoon and evening hours. The limited instability caused the line to be low topped and to produce little lightning, another common characteristic of cold season severe weather events. However, the strong shear and forcing contributed to the line producing widespread damaging wind across the region. Many measured wind gusts to severe strength (> 50 kt) were recorded, with numerous downed trees and wires causing tens of thousands of power outages across several states. Several mesovorticies were observed on radar, and NWS meteorologists studied multiple areas of enhanced damage for signs of possible brief tornadoes. However, it was concluded that all the damage was most likely due to straight line winds. Thankfully, no injuries or fatalities were reported during this event.

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KDIX radar loop of the March 28, 2021 squall line at half hour increments from 2130 UTC 28 March 2021 to 0030 UTC 29 March 2021.

Meteorological Environment/Setup

Synoptic Overview at 12z 28 March 2021 (courtesy of SPC)

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Figure 1: 250-mb analysis Figure 2: 300-mb analysis Figure 3: 500-mb analysis
 
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Figure 4: 700-mb analysis Figure 5: 850-mb analysis Figure 6: 925-mb analysis

Synoptic Overview at 00z 29 March 2021 (courtesy of SPC)

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Figure 7: 250-mb analysis Figure 8: 300-mb analysis Figure 9: 500-mb analysis
 
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Figure 10: 700-mb analysis Figure 11: 850-mb analysis Figure 12: 925-mb analysis
 

Surface Maps (courtesy of WPC)

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Figure 13: 12z surface map Figure 14: 15z surface map Figure 15: 18z surface map
 
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Figure 16: 21z surface map Figure 17: 00z surface map Figure 18: 03z surface map

Observed Soundings
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Figure 19: 12z Sterling, VA sounding Figure 20: 12z Wallops Island, VA sounding Figure 21: 12z Long Island, NY sounding
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Figure 22: 0z Sterling, VA sounding Figure 23: 0z Wallops Island, VA sounding Figure 24: 0z Long Island, NY sounding

Preliminary Storm Reports

prelimreports prelimreports prelimreports
Figure 1: National Preliminary Reports 12z 28 March 2021 to 12z 29 March 2021. Figure 2: Zoomed Preliminary Reports for the same period. Figure 3: March 28 1630z SPC Convective Outlook.

Preliminary Local Storm Reports

 

NWUS51 KPHI 291030
LSRPHI

PRELIMINARY LOCAL STORM REPORT...SUMMARY
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
630 AM EDT MON MAR 29 2021

...SEVERE WEATHER REPORTS FROM MARCH 28 2021...

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

0615 PM     TSTM WND DMG     1 NW HONEY BROOK        40.11N 75.93W
03/28/2021                   CHESTER            PA   FIRE DEPT/RESCUE 

            TREE DOWN ONTO WIRES ON RESERVOIR RD. TIME 
            ESTIMATED FROM RADAR. 

0619 PM     TSTM WND DMG     1 SSW WEST SADSBURY TWP 39.96N 75.97W
03/28/2021                   CHESTER            PA   FIRE DEPT/RESCUE 

            MULTIPLE DOWNED TREE AND WIRE REPORTS ON 
            STRASBURG RD. TIME ESTIMATED FROM RADAR. 

0619 PM     TSTM WND DMG     2 NNW HIGHLAND TWP.     39.95N 75.88W
03/28/2021                   CHESTER            PA   UTILITY COMPANY  

            DOWNED WIRES NEAR HIGHLAND ROAD AND TIMACULA 
            ROAD. TIME ESTIMATED FROM RADAR. 

0619 PM     TSTM WND DMG     1 S WAGONTOWN           40.00N 75.85W
03/28/2021                   CHESTER            PA   UTILITY COMPANY  

            DOWNED TREES AND WIRES NEAR ZALESKI ROAD. 
            TIME ESTIMATED FROM RADAR. 

0625 PM     TSTM WND DMG     2 WNW ELK TWP           39.73N 75.90W
03/28/2021                   CHESTER            PA   UTILITY COMPANY  

            DOWNED WIRES NEAR GLEN HOPE ROAD. TIME 
            ESTIMATED FROM RADAR. 

0625 PM     TSTM WND DMG     1 ESE MODENA            39.95N 75.78W
03/28/2021                   CHESTER            PA   FIRE DEPT/RESCUE 

            TREE DOWN BLOCKING MORTONVILLE RD. TIME 
            ESTIMATED FROM RADAR. 

0625 PM     TSTM WND DMG     1 SSW WEST MARLBOROUGH  39.90N 75.82W
03/28/2021                   CHESTER            PA   UTILITY COMPANY  

            DOWNED WIRES NEAR WINTERWOOD LANE. TIME 
            ESTIMATED FROM RADAR. 

0631 PM     TSTM WND DMG     1 SSE DOWNINGTON        39.99N 75.69W
03/28/2021                   CHESTER            PA   UTILITY COMPANY  

            DOWNED WIRES ON OLD TROLLEY ROAD. TIME 
            ESTIMATED FROM RADAR. 

0634 PM     TSTM WND DMG     NORTH STAR              39.76N 75.72W
03/28/2021                   NEW CASTLE         DE   DEPT OF HIGHWAYS 

            DOWNED TREE ON NORTH STAR ROAD. TIME 
            ESTIMATED FROM RADAR. 

0634 PM     TSTM WND DMG     2 NNE BROOKSIDE         39.69N 75.72W
03/28/2021                   NEW CASTLE         DE   UTILITY COMPANY  

            SEVERAL REPORTS OF DOWNED TREE LIMBS AND 
            POWER LINES IN THE WINDY HILLS AREA. TIME 
            ESTIMATED FROM RADAR. 

0635 PM     TSTM WND GST     2 SW BROOKSIDE          39.65N 75.75W
03/28/2021  M68 MPH          NEW CASTLE         DE   MESONET          

            DE DOT GAUGE. 

0635 PM     TSTM WND DMG     2 SSE LANDENBERG        39.75N 75.76W
03/28/2021                   CHESTER            PA   FIRE DEPT/RESCUE 

            TREE AND WIRE DOWN AND ON FIRE ON YEATMANS 
            STATION RD AND QUARTZ MILL RD. 

0638 PM     TSTM WND DMG     1 SSW WEST CHESTER      39.95N 75.60W
03/28/2021                   CHESTER            PA   UTILITY COMPANY  

            DOWNED TREES AND WIRES NEAR COLLEGE AVENUE. 
            TIME ESTIMATED FROM RADAR. 

0638 PM     TSTM WND DMG     1 SSW WEST CHESTER      39.95N 75.61W
03/28/2021                   CHESTER            PA   COUNTY OFFICIAL  

            DOWNED TREE ON ROSEDALE AVENUE. TIME 
            ESTIMATED FROM RADAR. 

0639 PM     TSTM WND DMG     2 SSE WEST CHESTER      39.94N 75.58W
03/28/2021                   CHESTER            PA   UTILITY COMPANY  

            DOWNED WIRES NEAR MATLACK STREET. TIME 
            ESTIMATED FROM RADAR. 

0639 PM     TSTM WND DMG     2 NE WASHINGTON         40.78N 74.96W
03/28/2021                   WARREN             NJ   UTILITY COMPANY  

            DOWNED TREES AND POWER LINES NEAR WESTERVELT 
            ROAD. TIME ESTIMATED FROM RADAR. 

0639 PM     TSTM WND DMG     THE CEDARS              39.74N 75.63W
03/28/2021                   NEW CASTLE         DE   UTILITY COMPANY  

            SEVERAL REPORTS OF DOWNED TREE LIMBS AND 
            POWER LINES IN THE ALBERTSON PARK AREA. TIME 
            ESTIMATED FROM RADAR. 

0640 PM     TSTM WND DMG     BIRMINGHAM TWP          39.89N 75.60W
03/28/2021                   CHESTER            PA   FIRE DEPT/RESCUE 

            TREE AND WIRES DOWN ON CREEK RD. TIME 
            ESTIMATED FROM RADAR. 

0642 PM     TSTM WND DMG     1 WNW MILLINGTON        39.26N 75.86W
03/28/2021                   KENT               MD   DEPT OF HIGHWAYS 

            DOWNED TREES AND WIRES NEAR THE INTERSECTION 
            OF STATE HIGHWAY 291 AND U.S. HIGHWAY 301. 
            TIME ESTIMATED FROM RADAR. 

0642 PM     TSTM WND DMG     NEW CASTLE              39.66N 75.57W
03/28/2021                   NEW CASTLE         DE   TRAINED SPOTTER  

            A COUPLE OF LIGHT POLES BLOWN OVER IN A 
            PARKING LOT. 

0642 PM     TSTM WND DMG     3 SSW STARKEY CORNER    39.09N 76.03W
03/28/2021                   QUEEN ANNES       MD   DEPT OF HIGHWAYS 

            OUTFLOW FROM STORMS DOWNED TREES AND WIRES 
            IN PORTIONS OF QUEEN ANNES COUNTY ALONG 
            STATE HIGHWAY 213 NORTH OF CENTREVILLE AND 
            SOUTH OF CHURCH HILL. TIME ESTIMATED FROM 
            RADAR. 

0644 PM     TSTM WND GST     NEW CASTLE COUNTY AIRPO 39.68N 75.61W
03/28/2021  M60 MPH          NEW CASTLE         DE   ASOS             

            KILG ASOS. 

0646 PM     TSTM WND DMG     3 SSE SASSAFRAS         39.34N 75.77W
03/28/2021                   KENT               MD   UTILITY COMPANY  

            DOWNED TREES AND WIRES NEAR GOLFS CALDWELL 
            ROAD. TIME ESTIMATED FROM RADAR. 

0647 PM     TSTM WND DMG     CRAGMERE                39.77N 75.49W
03/28/2021                   NEW CASTLE         DE   UTILITY COMPANY  

            SEVERAL REPORTS OF DOWNED TREE LIMBS AND 
            POWER LINES IN THE BELLEFONTE AREA. TIME 
            ESTIMATED FROM RADAR. 

0647 PM     TSTM WND GST     1 S ODESSA              39.44N 75.66W
03/28/2021  M76 MPH          NEW CASTLE         DE   DEPT OF HIGHWAYS 

            DEDOT GAUGE AT U.S. HIGHWAY 1 AT THE 
            APPOQUINIMINK RIVER. 

0648 PM     TSTM WND DMG     1 ENE WILLISTOWN TWP    40.01N 75.48W
03/28/2021                   CHESTER            PA   FIRE DEPT/RESCUE 

            TREE DOWN BLOCKING THE ROAD ON WEST CHESTER 
            PIKE AT DELCHESTER RD. TIME ESTIMATED FROM 
            RADAR. 

0648 PM     TSTM WND DMG     2 ENE BERWYN            40.06N 75.41W
03/28/2021                   CHESTER            PA   FIRE DEPT/RESCUE 

            TREE DOWN BLOCKING MEADOWBANK RD. TIME 
            ESTIMATED FROM RADAR. 

0650 PM     TSTM WND GST     SHELLBURNE              39.78N 75.51W
03/28/2021  M64 MPH          NEW CASTLE         DE   DEPT OF HIGHWAYS 

            DEDOT GAUGE AT I-95 AND MARSH ROAD. 

0650 PM     TSTM WND DMG     MIDDLETOWN TWP          39.90N 75.43W
03/28/2021                   DELAWARE           PA   FIRE DEPT/RESCUE 

            TREE AND WIRES DOWN ON MIDDLETOWN RD. 

0650 PM     TSTM WND DMG     ASTON TWP               39.87N 75.43W
03/28/2021                   DELAWARE           PA   PUBLIC           

            MPING REPORT OF LARGE TREE LIMBS OR POWER 
            POLES DOWN. TIME ESTIMATED FROM RADAR. 

0650 PM     TSTM WND DMG     RADNOR TOWNSHIP         40.03N 75.37W
03/28/2021                   DELAWARE           PA   FIRE DEPT/RESCUE 

            DOWNED TREE AND WIRES IN RADNOR TWP. TIME 
            ESTIMATED FROM RADAR. 

0652 PM     TSTM WND DMG     BOOTHWYN                39.83N 75.44W
03/28/2021                   DELAWARE           PA   UTILITY COMPANY  

            DOWNED TREE LIMBS AND WIRES NEAR SECOND 
            AVENUE. TIME ESTIMATED FROM RADAR. 

0652 PM     TSTM WND DMG     OLDMANS TWP.            39.76N 75.42W
03/28/2021                   SALEM              NJ   UTILITY COMPANY  

            SEVERAL REPORTS OF DOWNED WIRES FROM PENNS 
            GROVE TO BECKETT. TIME ESTIMATED FROM RADAR. 

0652 PM     TSTM WND DMG     1 NW WHITEMARSH TWP     40.09N 75.26W
03/28/2021                   MONTGOMERY         PA   UTILITY COMPANY  

            SEVERAL REPORTS OF DOWNED TREE LIMBS AND 
            WIRES IN THE PLYMOUTH MEETING AREA. TIME 
            ESTIMATED FROM RADAR. 

0652 PM     TSTM WND DMG     3 NNW SERGEANTSVILLE    40.48N 74.97W
03/28/2021                   HUNTERDON          NJ   UTILITY COMPANY  

            DOWNED TREES AND WIRES NEAR LOCKTOWN ROAD. 
            TIME ESTIMATED FROM RADAR. 

0654 PM     MARINE TSTM WIND 1 NNE DELAWARE CITY     39.58N 75.59W
03/28/2021  M46 MPH          NEW CASTLE         DE   MESONET          

             

0654 PM     TSTM WND DMG     CHESTER                 39.85N 75.37W
03/28/2021                   DELAWARE           PA   FIRE DEPT/RESCUE 

            SEVERAL DOWNED TREE AND WIRE REPORTS IN 
            CHESTER. TIME ESTIMATED FROM RADAR. 

0654 PM     TSTM WND DMG     1 W SERGEANTSVILLE      40.44N 74.96W
03/28/2021                   HUNTERDON          NJ   UTILITY COMPANY  

            DOWNED TREES AND WIRES NEAR ROSEMONT RINGOES 
            ROAD. TIME ESTIMATED FROM RADAR. 

0655 PM     TSTM WND DMG     BROOKHAVEN              39.87N 75.38W
03/28/2021                   DELAWARE           PA   PUBLIC           

            ESTIMATED WINDS OVER 60 MPH WITH DOWNED 
            POWER LINES IN BROOKHAVEN. 

0657 PM     TSTM WND DMG     2 E DELAWARE TWP        40.45N 74.92W
03/28/2021                   HUNTERDON          NJ   911 CALL CENTER  

            TREE AND WIRES DOWN NEAR EAST AMWELL. TIME 
            ESTIMATED FROM RADAR. 

0657 PM     TSTM WND DMG     2 E ABINGTON            40.12N 75.08W
03/28/2021                   MONTGOMERY         PA   FIRE DEPT/RESCUE 

            TREE AND WIRES DOWN ACROSS THE ROAD ON 
            WASHINGTON LN AT STOCKTON RD. TIME ESTIMATED 
            FROM RADAR. 

0658 PM     TSTM WND DMG     MORTON                  39.91N 75.32W
03/28/2021                   DELAWARE           PA   UTILITY COMPANY  

            SEVERAL REPORTS OF POWER LINES DOWN FROM 
            SYCAMORE HILLS TO BROOMALL. TIME ESTIMATED 
            FROM RADAR. 

0658 PM     TSTM WND DMG     PENN WYNNE              39.99N 75.28W
03/28/2021                   MONTGOMERY         PA   UTILITY COMPANY  

            SEVERAL REPORTS OF DOWNED TREE LIMBS AND 
            WIRES IN THE PENN WYNNE AREA. TIME ESTIMATED 
            FROM RADAR. 

0659 PM     TSTM WND DMG     2 E ABINGTON            40.12N 75.10W
03/28/2021                   MONTGOMERY         PA   UTILITY COMPANY  

            SEVERAL REPORTS OF DOWNED WIRES IN THE 
            ABINGTON AREA. TIME ESTIMATED FROM RADAR. 

0700 PM     TSTM WND DMG     UPPER DARBY TWP         39.96N 75.29W
03/28/2021                   DELAWARE           PA   FIRE DEPT/RESCUE 

            TREE AND WIRES DOWN ON PINE ST. 

0700 PM     TSTM WND DMG     WEST AMWELL TWP         40.36N 74.90W
03/28/2021                   HUNTERDON          NJ   911 CALL CENTER  

            TREE AND WIRES DOWN IN WEST AMWELL. TIME 
            ESTIMATED FROM RADAR. 

0703 PM     TSTM WND DMG     CHELTENHAM              40.06N 75.11W
03/28/2021                   MONTGOMERY         PA   UTILITY COMPANY  

            SEVERAL REPORTS OF DOWNED TREE LIMBS AND 
            WIRES IN CHELTENHAM AND ELKINS PARK. TIME 
            ESTIMATED FROM RADAR. 

0703 PM     TSTM WND DMG     1 W STENTON             39.99N 75.18W
03/28/2021                   PHILADELPHIA       PA   UTILITY COMPANY  

            DOWNED WIRES NEAR SUSQUEHANNA AVENUE. TIME 
            ESTIMATED FROM RADAR. 

0704 PM     TSTM WND DMG     NATIONAL PARK           39.86N 75.18W
03/28/2021                   GLOUCESTER         NJ   UTILITY COMPANY  

            DOWNED WIRES NEAR GROVE AVENUE. TIME 
            ESTIMATED FROM RADAR. 

0705 PM     TSTM WND DMG     WESTVILLE               39.87N 75.13W
03/28/2021                   GLOUCESTER         NJ   TRAINED SPOTTER  

            TREE LIMBS AND UTILITY WIRES DOWN. 

0706 PM     TSTM WND DMG     YARDLEY                 40.24N 74.84W
03/28/2021                   BUCKS              PA   UTILITY COMPANY  

            DOWNED WIRES REPORTED IN A FEW LOCATIONS 
            BETWEEN YARDLEY AND MORRISVILLE. TIME 
            ESTIMATED FROM RADAR. 

0706 PM     TSTM WND DMG     2 WSW LANGHORNE         40.17N 74.95W
03/28/2021                   BUCKS              PA   UTILITY COMPANY  

            DOWNED TREE LIMBS AND WIRES NEAR ARROWHEAD 
            DRIVE. TIME ESTIMATED FROM RADAR. 

0707 PM     TSTM WND DMG     DEPTFORD                39.83N 75.16W
03/28/2021                   GLOUCESTER         NJ   PUBLIC           

            TREES, UTILITY POLES, AND FENCES BLOWN DOWN 
            IN DEPTFORD. TIME ESTIMATED FROM RADAR. 

0708 PM     TSTM WND DMG     1 ESE WOODBURY          39.83N 75.14W
03/28/2021                   GLOUCESTER         NJ   UTILITY COMPANY  

            DOWNED WIRES NEAR COOPER STREET. TIME 
            ESTIMATED FROM RADAR. 

0708 PM     TSTM WND DMG     2 E FEASTERVILLE-TREVOS 40.14N 74.94W
03/28/2021                   BUCKS              PA   UTILITY COMPANY  

            DOWNED TREE LIMBS AND WIRES NEAR CANTERBERRY 
            COURT. TIME ESTIMATED FROM RADAR. 

0709 PM     TSTM WND DMG     2 W PROSPECT PARK       40.24N 74.81W
03/28/2021                   MERCER             NJ   UTILITY COMPANY  

            SEVERAL REPORTS OF DOWNED TREE LIMBS AND 
            WIRES NEAR SANHICAN DRIVE. TIME ESTIMATED 
            FROM RADAR. 

0709 PM     TSTM WND DMG     1 NW SKILLMAN           40.43N 74.73W
03/28/2021                   SOMERSET           NJ   UTILITY COMPANY  

            DOWNED TREE LIMBS AND WIRES NEAR SERVIS 
            ROAD. TIME ESTIMATED FROM RADAR. 

0709 PM     TSTM WND DMG     2 ESE HOPEWELL          40.38N 74.73W
03/28/2021                   MERCER             NJ   UTILITY COMPANY  

            DOWNED TREE LIMBS AND WIRES NEAR PROVINCE 
            LINE ROAD. TIME ESTIMATED FROM RADAR. 

0709 PM     TSTM WND DMG     1 SE NESHANIC STATION   40.50N 74.72W
03/28/2021                   SOMERSET           NJ   UTILITY COMPANY  

            DOWNED TREES AND WIRES NEAR ZION ROAD IN 
            NESHANIC. TIME ESTIMATED FROM RADAR. 

0710 PM     TSTM WND DMG     EDGEWATER PARK TWP      40.05N 74.92W
03/28/2021                   BURLINGTON         NJ   NWS EMPLOYEE     

            NWS EMPLOYEE ESTIMATED 60 MPH WIND GUSTS 
            WITH DOWNED FENCING AND TREE BRANCHES. 

0710 PM     TSTM WND DMG     GLASSBORO               39.70N 75.11W
03/28/2021                   GLOUCESTER         NJ   TRAINED SPOTTER  

            TREE LIMBS AND UTILITY WIRES DOWN. 

0711 PM     TSTM WND DMG     1 NW BLACKWOOD          39.81N 75.08W
03/28/2021                   CAMDEN             NJ   UTILITY COMPANY  

            DOWNED TREE LIMBS AND WIRES NEAR GOOD INTENT 
            ROAD. TIME ESTIMATED FROM RADAR. 

0712 PM     TSTM WND GST     HADDON TWP              39.91N 75.05W
03/28/2021  E60 MPH          CAMDEN             NJ   NWS EMPLOYEE     

            NWS EMPLOYEE ESTIMATED 60 MPH WIND GUSTS. 
            TIME ESTIMATED FROM RADAR. 

0712 PM     TSTM WND DMG     HILLSBOROUGH TWP        40.50N 74.67W
03/28/2021                   SOMERSET           NJ   911 CALL CENTER  

            SIX TO EIGHT POWER POLES AND AROUND 10 TREES 
            REPORTED DOWN IN HILLSBOROUGH. TIME 
            ESTIMATED FROM RADAR. 

0714 PM     TSTM WND DMG     1 N MONTGOMERY TWP      40.44N 74.68W
03/28/2021                   SOMERSET           NJ   911 CALL CENTER  

            A FEW REPORTS OF DOWNED TREES AND WIRES ON 
            THE NORTH SIDE OF MONTGOMERY TWP. TIME 
            ESTIMATED FROM RADAR. 

0715 PM     TSTM WND DMG     2 E BELLE MEAD          40.47N 74.63W
03/28/2021                   SOMERSET           NJ   UTILITY COMPANY  

            DOWNED TREES AND WIRES NEAR WILLOW ROAD. 
            TIME ESTIMATED FROM RADAR. 

0715 PM     TSTM WND GST     TRENTON                 40.22N 74.76W
03/28/2021  M63 MPH          MERCER             NJ   PUBLIC           

            63 MPH THUNDERSTORM WIND GUST MEASURED VIA A 
            HOME WEATHER STATION. 

0715 PM     TSTM WND DMG     2 NNW CLAYTON           39.68N 75.10W
03/28/2021                   GLOUCESTER         NJ   DEPT OF HIGHWAYS 

            DOWNED UTILITY POLE ON STATE HIGHWAY 47 
            SOUTH OF U.S. HIGHWAY 322. TIME ESTIMATED 
            FROM RADAR. 

0717 PM     TSTM WND DMG     1 WNW FELLOWSHIP        39.93N 74.98W
03/28/2021                   CAMDEN             NJ   UTILITY COMPANY  

            DOWNED UTILITY POLE NEAR CHURCH ROAD. TIME 
            ESTIMATED FROM RADAR. 

0719 PM     TSTM WND DMG     1 ENE WEST WINDSOR TWP. 40.31N 74.62W
03/28/2021                   MERCER             NJ   UTILITY COMPANY  

            DOWNED TREE LIMBS AND WIRES NEAR CLARKSVILLE 
            ROAD AND PENN LYLE ROAD. TIME ESTIMATED FROM 
            RADAR. 

0720 PM     TSTM WND DMG     WILLIAMSTOWN            39.69N 74.98W
03/28/2021                   GLOUCESTER         NJ   PUBLIC           

            MULTIPLE TRANFORMERS OBSERVED BLOWING OUT IN 
            WILLIAMSTOWN. TIME ESTIMATED FROM RADAR. 

0720 PM     TSTM WND GST     1 NE MAGNOLIA           39.09N 75.46W
03/28/2021  M60 MPH          KENT               DE   DEPT OF HIGHWAYS 

            DEDOT GAUGE NEAR STATE ROUTE 1 AND TRAP 
            SHOOTERS ROAD. TIME ESTIMATED FROM RADAR. 

0721 PM     TSTM WND DMG     1 ESE SICKLERVILLE      39.71N 74.95W
03/28/2021                   CAMDEN             NJ   UTILITY COMPANY  

            SEVERAL REPORTS OF DOWNED TREES AND WIRES IN 
            SICKLERVILLE. TIME ESTIMATED FROM RADAR. 

0726 PM     TSTM WND DMG     2 NNE MILFORD           38.94N 75.42W
03/28/2021                   KENT               DE   UTILITY COMPANY  

            DOWNED UTILITY POLE AND WIRES NEAR NEW WHARF 
            ROAD. TIME ESTIMATED FROM RADAR. 

0727 PM     TSTM WND DMG     2 NE ALLENTOWN          40.20N 74.56W
03/28/2021                   MERCER             NJ   NWS EMPLOYEE     

            TREE AND WIRES DOWN ON OLD YORK RD. ROAD 
            CLOSED BETWEEN PERRINEVILE RD AND SHARON RD. 
            TIME ESTIMATED FROM RADAR. 

0727 PM     TSTM WND DMG     3 NE JOBSTOWN           40.06N 74.66W
03/28/2021                   BURLINGTON         NJ   UTILITY COMPANY  

            DOWNED TREES AND WIRES NEAR MOUNT PLEASANT 
            ROAD. TIME ESTIMATED FROM RADAR. 

0727 PM     TSTM WND DMG     1 WNW EAST BRUNSWICK    40.42N 74.43W
03/28/2021                   MIDDLESEX          NJ   UTILITY COMPANY  

            DOWNED TREE LIMBS AND WIRES NEAR DUNHAMS 
            CORNER ROAD. TIME ESTIMATED FROM RADAR. 

0730 PM     MARINE TSTM WIND FORTESCUE               39.24N 75.18W
03/28/2021  M45 MPH          CUMBERLAND         NJ   MESONET          

            NJWXNET GAUGE. 

0733 PM     TSTM WND DMG     2 SSE SOUTH RIVER       40.43N 74.37W
03/28/2021                   MIDDLESEX          NJ   UTILITY COMPANY  

            DOWNED TREE LIMBS AND WIRES NEAR DONALD 
            ROAD. TIME ESTIMATED FROM RADAR. 

0736 PM     TSTM WND DMG     2 ESE CLARKSBURG        40.18N 74.41W
03/28/2021                   MONMOUTH           NJ   UTILITY COMPANY  

            DOWNED TREES AND WIRES ON CARRS TAVERN ROAD. 
            TIME ESTIMATED FROM RADAR. 

0737 PM     TSTM WND DMG     1 SE PARLIN             40.45N 74.30W
03/28/2021                   MIDDLESEX          NJ   DEPT OF HIGHWAYS 

            DOWNED UTILITY POLE ON U.S. HIGHWAY 9 NEAR 
            ERNSTON ROAD. TIME ESTIMATED FROM RADAR. 

0738 PM     TSTM WND GST     JOINT BASE MDL          40.02N 74.59W
03/28/2021  M70 MPH          BURLINGTON         NJ   AWOS             

            MCGUIRE AFB AWOS. 

0738 PM     TSTM WND DMG     MATAWAN                 40.42N 74.23W
03/28/2021                   MONMOUTH           NJ   TRAINED SPOTTER  

            SOME LARGE TREES DOWN IN MATAWAN. TIME 
            ESTIMATED FROM RADAR. 

0740 PM     TSTM WND DMG     1 W MATAWAN             40.41N 74.26W
03/28/2021                   MIDDLESEX          NJ   UTILITY COMPANY  

            DOWNED TREES AND WIRES NEAR OLD BRIDGE 
            MATAWAN ROAD. TIME ESTIMATED FROM RADAR. 

0742 PM     TSTM WND DMG     MARLBORO                40.32N 74.25W
03/28/2021                   MONMOUTH           NJ   PUBLIC           

            NUMEROUS TREES DOWN IN MARLBORO. TIME 
            ESTIMATED FROM RADAR. 

0743 PM     TSTM WND DMG     5 ESE NEW EGYPT         40.03N 74.44W
03/28/2021                   OCEAN              NJ   UTILITY COMPANY  

            DOWNED TREE LIMBS AND WIRES NEAR PINEHURST 
            ROAD. TIME ESTIMATED FROM RADAR. 

0746 PM     TSTM WND DMG     1 NNW HAZLET            40.43N 74.19W
03/28/2021                   MONMOUTH           NJ   DEPT OF HIGHWAYS 

            DOWNED TREE AND WIRES ON STATE HIGHWAY 36 
            NEAR MIDDLE ROAD IN HAZLET TWP. TIME 
            ESTIMATED FROM RADAR. 

0752 PM     TSTM WND DMG     2 E LAKEHURST           40.01N 74.27W
03/28/2021                   OCEAN              NJ   TRAINED SPOTTER  

            NUMEROUS TREES AND WIRES DOWN IN THE LEISURE 
            VILLAGE WEST AND PINE LAKE PARK AREAS OF 
            MANCHESTER TOWNSHIP. TIME ESTIMATED FROM 
            RADAR. 

0752 PM     TSTM WND DMG     1 SSW TINTON FALLS      40.28N 74.10W
03/28/2021                   MONMOUTH           NJ   UTILITY COMPANY  

            DOWNED TREES AND WIRES NEAR SQUANKUM ROAD. 
            TIME ESTIMATED FROM RADAR. 

0754 PM     TSTM WND DMG     ATLANTIC HIGHLANDS      40.41N 74.04W
03/28/2021                   MONMOUTH           NJ   UTILITY COMPANY  

            SEVERAL REPORTS OF DOWNED TREE LIMBS AND 
            POWER LINES IN THE ATLANTIC HIGHLANDS AREA. 
            TIME ESTIMATED FROM RADAR. 

0756 PM     TSTM WND DMG     1 WSW OAKHURST          40.26N 74.03W
03/28/2021                   MONMOUTH           NJ   UTILITY COMPANY  

            DOWNED TREES AND WIRES NEAR LINCOLN AVENUE. 
            TIME ESTIMATED FROM RADAR. 

0800 PM     TSTM WND DMG     NEPTUNE TWP             40.22N 74.07W
03/28/2021                   MONMOUTH           NJ   EMERGENCY MNGR   

            DAMAGE REPORTED ON NEW YORK RD. DOWNED ROAD 
            SIGNS AND A POSSIBLE PARTIAL ROOF COLLAPSE. 
            TIME ESTIMATED FROM RADAR. 

0810 PM     MARINE TSTM WIND 2 SSW MANTOLOKING       40.01N 74.06W
03/28/2021  M46 MPH          OCEAN              NJ   MESONET          

            WXFLOW SENSOR. 

0812 PM     MARINE TSTM WIND 5 SE MYSTIC ISLAND      39.51N 74.32W
03/28/2021  M42 MPH          OCEAN              NJ   MESONET          

            HADS SENSOR. 

0815 PM     MARINE TSTM WIND NORTH WILDWOOD          39.01N 74.80W
03/28/2021  M48 MPH          CAPE MAY           NJ   MESONET          

             

0816 PM     MARINE TSTM WIND 2 SW BEACH HAVEN        39.54N 74.26W
03/28/2021  M43 MPH          OCEAN              NJ   MESONET          

             

0828 PM     MARINE TSTM WIND INDIAN BEACH            38.68N 75.08W
03/28/2021  M54 MPH          SUSSEX             DE   MESONET          

            WXFLOW SENSOR. 


&&

$$

CMS/MJG/JEO

Public Information Statement - Straight Line Winds

PUBLIC INFORMATION STATEMENT
National Weather Service MOUNT HOLLY NJ
1049 AM EDT Mon Mar 29 2021

...UPDATE ON STORM DAMAGE FROM SUNDAY EVENING...

The National Weather Service in Mount Holly received numerous 
reports of damage caused by a line of showers and thunderstorms 
which moved through the region on Sunday evening. Several wind gusts 
of 60 to 70 mph were measured across southeast Pennsylvania, 
Delaware, and New Jersey.

Based on an analysis of the damage, radar data, coordination with 
local emergency management, and eyewitness accounts, it has been 
determined that all damage reports received so far were due to 
straight line winds. This includes in Neptune Twp, New Jersey, where 
very prelminary accounts from first responders on Sunday evening led 
to speculation of a possible tornado. Damage in that area, including 
to the roof of the America's Best Value Inn, was consistent with 
straight line winds of around 70 mph, which likely caused the roof 
to peel off.

The National Weather Service will continue to investigate any 
additional damage reports should they be received, and would like to 
thank the Monmouth County Office of Emergency Management, and the 
Neptune Twp Office of Emergency Management, for their assistance.

$$

JEO/JJM

Radar Interrogation

Notable Radar Imagery (GR2Analyst)

Environment Environment
Figure 1: KDIX radar reflectivity factor (left) and base velocity (right) for the 0.5 degree elevation angle valid at 2229 UTC 28 March 2021. By this time, numerous reports of wind damage were beginning to occur as the line intensified. The downstream environment supported continued maintenance of the squall line all the way to the Atlantic coast, prompting the issance of Severe Thunderstorm Warnings for most of New Jersey, eastern Pennsylvania, and northern Delaware as it moved east. Figure 2: KDIX radar reflectivity factor (left) and storm relative motion (SRM, right) valid at 2304 UTC 28 March 2021. As the line progressed eastward, several attempted mesovortex generations occurred. These circulations can sometimes produce brief tornadoes intertwined with more widespread straight line wind damage. One such example occurred here, very near Philadelphia International Airport. A hook feature is seen in the reflectivity, with a weak but well-defined area of rotation in the SRM.
Environment Environment
Figure 3: Same as Figure 1 valid at 2327 UTC 28 March 2021. Some bowing segments also developed along the line as it moved eastward, which led to areas of greater wind damage. One such segment passed near the Mount Holly, NJ area, not far from the NWS office. NWS meteorologists estimated winds of around 50 mph as the storms passed, but higher wind gusts of 60 to 70 mph likely occurred very nearby, with numerous reports of damage and power outages in the vicinity. Figure 4: A KDIX along-line radar reflectivity cross-section, for the same time and area as Figure 3. The shallow nature of this squall line is evident. Convective cloud tops extend to a height of barely 20,000 feet, and the height of the 50 dbz echo (red pixels) is mainly below 10,000 ft. This is typical of cold season environments with strong shear and forcing but weak instability. The line produced very little lightning as it moved east, though some electrical activity did occur, with a couple of lightning flashes noted by NWS meteorologists as the line passed over the office.
Environment Environment
Figure 5: Same as Figure 2 valid at 0000 UTC 29 March 2021. The most publicized damage report from this event came in the area of Neptune Twp, NJ. A motel had a large section of its roof removed, and a couple of small boats were shifted from a back bay onto a street in the same area. Radar at the time showed an east-northeast moving bowing segment approaching the area. SRM showed some evidence of weak rotation in the area, but it was very broad and ill-defined, though the KDIX radar does not have a favorable viewing angle for velocity data in that area. The nature of the damage, which involved a transport of debris in a broadly west to east direction, suggested straight line winds were most likely responsible, and that building design and construction likely contributed to the roofing loss at the affected motel. Figure 6: Same as Figure 2 valid at 0004 UTC 29 March 2021, just a few minutes after the image in Figure 5. A bit further south along the New Jersey shore, another mesovortex, perhaps the most impressive of the event, is seen northeast of Toms River, approaching the coast. An area of fairly well-defined rotation is seen in the SRM. However, like all such signatures in this event, the rotation was very fleeting, and had dissipated within a couple of minutes. It cannot be entirely ruled out that one or more brief tornado touchdowns occurred in the local area, but no conclusive evidence of such was found.