Scattered storms formed ahead of an approaching cold front during the afternoon and evening of July 6, 2023. A few of the cells merged to form a short-lived line that produced sporadic wind damage and a measured gust to 58 mph at Williamsport Regional Airport.
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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.
The episode as NWS CTP wrote it up.
Scattered storms formed ahead of an approaching cold front during the afternoon and evening of July 6, 2023. A few of the cells merged to form a short-lived line that produced sporadic wind damage and a measured gust to 58 mph at Williamsport Regional Airport.
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 State College, PA wrote its last area forecast discussion before the first event at Jul 6, 1:10 PM EST, 4 hours 10 minutes earlier.
Area Forecast Discussion National Weather Service State College PA 210 PM EDT Thu Jul 6 2023 .SYNOPSIS... Summertime heat and humidity will continue into the upcoming weekend with an increased chance for showers and thunderstorms expected through the weekend. Locally heavy rain is possible with a risk of flooding/runoff concerns Friday and Sunday, mainly across the Eastern half of the state. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... A quintessential summer day is underway with dewpoints in the mid 60s to low 70s across the area - firmly in the uncomfortable to oppressive category. As of 11:30AM, temperatures are already well into the 80s across the entire area with additional warming expected to push highs into the low 90s in the valleys and lower elevations of Central Pennsylvania. Regional satellite/day cloud phase RGB shows cumulus clouds building mainly along ridgetops and some horizontal convective rolls advecting into southeast PA with moist southeast flow. Scattered showers and thunderstorms will continue to develop and slowly drift northward and eventually eastward this afternoon. Mean 0-6km shear <20kt should result in non severe, slow moving, pulse type t-storms with brief heavy downpours in spots. Coverage of these storms should be widely scattered such that most locations stay dry for a majority of the day. Storm activity through early afternoon should be primarily confined to the Lower Susquehanna Valley. Later this afternoon and evening, there will be a better chance for areas in the Laurels and Northern Mountains to get in on the rainfall activity as broad scale lift ahead of the approaching cold front provides amplified forcing for ascent. Spotty rainfall totals through this evening could approach 0.5 inches. From a sensible weather standpoint, partly to mostly sunny, very warm and humid conditions are on tap for today. The combination of heat and humidity will result in heat index values ranging from the upper 80s to upper 90s. If you've got plans to hit the pool today or do anything outside, make sure to hydrate and take shelter if you hear thunder! && .SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/... Scattered convection should fade with loss of heating over most of Central PA tonight. However, the approach of an upstream trough and associated cold front will bring a renewed chance of showers/tsra across the NW Mtns toward dawn Friday. Thursday night will be another humid one with patchy fog in areas that receive rainfall this afternoon. Low temperatures will dip into the low 60s to low 70s, which is 5 to 10 degrees warmer than average for this time of year. Southeasterly flow will also lead to a deck of low clouds moving into southeast Pennsylvania toward daybreak. These clouds cloud be slow to erode and it may take a few hours for the sun to break out Friday morning in the Lower Susquehanna Valley. It's a rinse and repeat kind of pattern for Friday as heat, humidity, and afternoon showers and t-storms are again expected. The main difference is that a weak cold front will drift across the region and provide a bit more lift and resultant expanded coverage of showers. The CAPE/shear profile will not favor severe storms, but some heavy downpours remain likely especially with pwats climbing >1.5 inches ahead of the front. Forecast highs drop back by a few to several degrees given clouds and showers with highs ranging from 75-80F over the Alleghenies to 85-90F in the lower Susquehanna Valley. Some lower pwat air arrives behind the front and delivers a cooler night across the NW mtns with lows falling back into the mid 50s. Patchy fog should also develop again overnight into early Saturday morning thanks to recent rainfall and calm winds. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... All medium range guidance stalls the cold front east of the forecast area Saturday. However, an approaching upper level trough could support scattered PM convection. The focus by late in the weekend turns to a developing surface low over the Ohio Valley. Recent model runs have shown the low tracking slightly farther to the northeast, which has resulted in the area expecting the highest rainfall totals shifting east as well. Latest ensemble plumes indicate most likely rainfall between 0.5 and 1.5 inches, with locally higher amounts possible. Lingering showers appear possible Monday with the passage of the associated shortwave, then odds favor fair and seasonable conditions Tuesday, although a shower or thunderstorms cannot be ruled out in the afternoon. The end of the period will be characterized by an upper trough that develops over the Great Lakes. Showers associated with this feature and the associated cold front could arrive by Wednesday PM. && .AVIATION /18Z THURSDAY THROUGH TUESDAY/... Prevailing VFR. Isolated showers and t-storms are developing this afternoon and will continue to do so into the evening hours. Low clouds and fog could be more widespread tonight based on the NAM MOS which has a tendency to be too aggressive with IFR. Outlook... Fri...Periods of sub-VFR with showers & t-storms especially central and eastern sites. Fog psbl Friday night. Sat...Brief sub-VFR in sct t-storms mainly southeast 1/2. Fog psbl Sat night. Sun...Sub-VFR likely in rain and t-storms. Mon and Tue...Chance of showers and t-storms. && .CTP WATCHES/WARNINGS/ADVISORIES... None. && SYNOPSIS...Lambert/Steinbugl NEAR TERM...Lambert/Banghoff SHORT TERM...Lambert/Banghoff LONG TERM...Fitzgerald/Bauco AVIATION...Steinbugl/Gartner
Hazardous Weather Outlook National Weather Service State College PA 350 AM EDT Thu Jul 6 2023 PAZ004>006-010>012-017>019-024>028-033>037-041-042-045-046-049>053- 056>059-063>066-070800- Warren-McKean-Potter-Elk-Cameron-Northern Clinton-Clearfield- Northern Centre-Southern Centre-Cambria-Blair-Huntingdon-Mifflin- Juniata-Somerset-Bedford-Fulton-Franklin-Tioga-Northern Lycoming- Sullivan-Southern Clinton-Southern Lycoming-Union-Snyder-Montour- Northumberland-Columbia-Perry-Dauphin-Schuylkill-Lebanon-Cumberland- Adams-York-Lancaster- 350 AM EDT Thu Jul 6 2023 This Hazardous Weather Outlook is for central Pennsylvania. .DAY ONE...Today and tonight. The probability for widespread hazardous weather is low. .DAYS TWO THROUGH SEVEN...Friday through Wednesday. Scattered strong to potentially severe thunderstorms are possible Friday afternoon and evening, mainly across the eastern half of the state, as a weak cold front pushes east across Pennsylvania. In addition, locally heavy rain along with potential runoff and minor flooding concerns will exist Friday through Sunday over Southern and Eastern parts of the state. .SPOTTER INFORMATION STATEMENT... Spotters are encouraged to report significant hazardous weather.
Preliminary Local Storm Report
National Weather Service State College PA
1235 PM EDT Thu Jul 6 2023
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0308 PM Tornado 1 S Zion 40.91N 77.66W
07/02/2023 Centre PA NWS Storm Survey
NWS survey confirms an EF-1 tornado occurred
southeast of Zion, damaging several large
trees. Estimated max wind speed 93 mph.
Length 0.62 mi. Width 200 yds.
&&
JCGSpecial Weather Statement
National Weather Service State College PA
1254 PM EDT Thu Jul 6 2023
PAZ059-061730-
Lebanon PA-
1254 PM EDT Thu Jul 6 2023
...A STRONG THUNDERSTORM WILL IMPACT CENTRAL LEBANON COUNTY THROUGH
130 PM EDT...
At 1253 PM EDT, Doppler radar was tracking a strong thunderstorm over
Myerstown, moving north at 15 mph.
HAZARD...Wind gusts up to 50 mph.
SOURCE...Radar indicated.
IMPACT...Gusty winds could knock down tree limbs and blow around
unsecured objects.
Locations impacted include...
Lebanon, Annville, Myerstown, Pleasant Hill, Sand Hill, Newmanstown,
Lebanon South, Cleona, Avon, Richland, Fredericksburg, Lickdale,
Jonestown and Avon Heights.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
If outdoors, consider seeking shelter inside a building.
&&
LAT...LON 4032 7651 4049 7653 4050 7644 4037 7625
4036 7620 4032 7616
TIME...MOT...LOC 1653Z 173DEG 11KT 4040 7636
MAX HAIL SIZE...0.00 IN
MAX WIND GUST...50 MPH
BanghoffSpecial Weather Statement
National Weather Service State College PA
452 PM EDT Thu Jul 6 2023
PAZ011-012-017-018-062130-
Northern Centre PA-Northern Clinton PA-Cameron PA-Clearfield PA-
452 PM EDT Thu Jul 6 2023
...A STRONG THUNDERSTORM WILL IMPACT NORTHEASTERN CLEARFIELD...
NORTHWESTERN CENTRE...SOUTHEASTERN CAMERON AND WEST CENTRAL CLINTON
COUNTIES THROUGH 530 PM EDT...
At 451 PM EDT, Doppler radar was tracking a strong thunderstorm 20
miles northeast of Clearfield, moving northeast at 15 mph.
HAZARD...Wind gusts up to 50 mph and pea size hail.
SOURCE...Radar indicated.
IMPACT...Gusty winds could knock down tree limbs and blow around
unsecured objects. Minor hail damage to vegetation
possible.
Locations impacted include...
Karthaus and Pine Glen.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
If outdoors, consider seeking shelter inside a building.
&&
LAT...LON 4106 7806 4104 7819 4121 7822 4134 7807
4119 7780
TIME...MOT...LOC 2051Z 222DEG 15KT 4115 7808
MAX HAIL SIZE...0.25 IN
MAX WIND GUST...50 MPH
ColbertSpecial Weather Statement
National Weather Service State College PA
605 PM EDT Thu Jul 6 2023
PAZ065-062230-
York PA-
605 PM EDT Thu Jul 6 2023
...A STRONG THUNDERSTORM WILL IMPACT NORTHWESTERN YORK COUNTY THROUGH
630 PM EDT...
At 605 PM EDT, Doppler radar was tracking a strong thunderstorm near
Weigelstown, moving northwest at 5 mph.
HAZARD...Wind gusts up to 50 mph and pea size hail.
SOURCE...Radar indicated.
IMPACT...Gusty winds could knock down tree limbs and blow around
unsecured objects. Minor hail damage to vegetation
possible.
Locations impacted include...
Valley Green, Manchester, Goldsboro, York Haven, Lewisberry,
Newberrytown and Ski Roundtop Ski Area.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
If outdoors, consider seeking shelter inside a building.
Very heavy rainfall is also occurring with this storm and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.
&&
LAT...LON 4011 7694 4017 7686 4015 7675 4013 7674
4012 7672 4010 7669 4009 7669 4004 7675
4004 7683
TIME...MOT...LOC 2205Z 155DEG 5KT 4009 7679
MAX HAIL SIZE...0.25 IN
MAX WIND GUST...50 MPH
ColbertThe State College radar (KCCX), 133 km away, was scanning. The volume nearest the first event began at 22:20 UTC.
6 thunderstorm wind. Local standard time, as filed.
A severe thunderstorm producing winds estimated near 60 mph knocked down several trees along Garriston Road near Route 382 in Newberry Township, damaging an awning and puncturing a roof.
A severe thunderstorm producing winds estimated near 60 mph knocked down 30 to 40 trees in the vicinity of Mount Eagle Road and the Bald Eagle train tracks.
A severe thunderstorm producing winds estimated near 60 mph knocked down trees onto power lines near McClure.
A severe thunderstorm producing winds estimated near 60 mph knocked down trees and caused structural damage to a barn near Collomsville.
A severe thunderstorm producing winds estimated near 60 mph knocked down trees and wires and caused power outages north of Williamsport.
A severe thunderstorm produced winds approaching 60 mph at Williamsport Regional Airport.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Pennsylvania in 2023Every state in 2023This day in weather historyWarnings in Pennsylvania, July 2023
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: 1106766, 1106762, 1106764, 1106765, 1106763, 1106767.