A strong cold front, driven by an unusually strong upper-level trough and wind shear, interacted with a hot, humid, and unstable airmass over the Mid-Atlantic. This pattern resulted in the formation of lines of thunderstorms and several supercells.
Every event with a place to put it. Tap one for its entry below.
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 LWX wrote it up.
A strong cold front, driven by an unusually strong upper-level trough and wind shear, interacted with a hot, humid, and unstable airmass over the Mid-Atlantic. This pattern resulted in the formation of lines of thunderstorms and several supercells. The most widespread and significant wind damage was noted over northern Maryland, although pockets of considerable wind damage were noted over portions of northwestern Virginia and eastern West Virginia. Somewhat atypical for the Mid-Atlantic is late summer was the number of large hail reports, with multiple instances of giant hail noted.
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 Baltimore/Washington wrote its last area forecast discussion before the first event at Aug 7, 9:28 AM EST, 3 hours 10 minutes earlier.
Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
1028 AM EDT Mon Aug 7 2023
.SYNOPSIS...
Scattered to numerous strong to severe thunderstorms are expected
today as a strong cold front pushes through the region. High
pressure returns behind the front Tuesday into Wednesday with breezy
conditions. A warm frontal boundary approaches from the south
THursday into Friday bring additional showers and thunderstorms.
Unsettled conditions linger into the weekend.
&&
.NEAR TERM /THROUGH TONIGHT/...
The forecast remains on track with a mesoscale convective vortex
(MCV) lifting toward northwestern Pennsylvania. Some residual
showers are pushing through Garrett, Mineral, and Allegany
counties, but these are decaying with little to no lightning
left. Elsewhere, a stagnant area of stratus clouds sit from the
I-64 corridor northeastward into northern Virginia, as well as
the DC/Baltimore metros. However, the aircraft soundings (ACAR)
do show this low cloud deck being quite shallow in nature with a
depth of about 200 meters (~650 feet). Given the early August
solar insolation angle, these should burn off/erode within the
next hour or two. Farther west, the Shenandoah Valley is under
mainly sunny skies with convective initiation likely within the
next few hours.
Daytime heating brings temperatures into the upper 80s to low
90s. Combined with dew points in the low to mid 70s, expect peak
heat indices between 100- 105 east of the Blue Ridge, and 95-99
west. This moist and unstable environment will fuel the active
weather looming later in the day. Of note, the Storm
Prediction Center has upgraded the risk area to Moderate which
is seen only 2 to 3 times per decade in the area.
Looking ahead at this afternoon and evening, given that we
destabilize, all signs point to a likely widespread severe wind
event across our area, though all modes of severe weather are
possible. A large mid-level trough over the western OH Valley this
morning will move eastward toward the Central Appalachians, with two
surface lows noted early this morning - one over southern ON and the
other along the IN/IL border. These surface lows deepen through the
afternoon, with models indicating pressure in the low 1000mb range,
which is quite impressive for early August (for a non-tropical low).
Storms are expected to develop in a favorable environment today
where surface dew points in the low 70s and impressive mid-level
lapse rates of 6-7 C/km yield around 1500-2000 J/kg of MLCAPE
(SBCAPE up to 2500+ J/kg possible). Storms should easily become
organized with deep-layer shear of 35-50KT.
Multiple rounds of storms are likely to impact the area today. The
moist airmass, approaching PVA max, and remnant MCV could initiate
late morning to early afternoon activity west of I-81 into north-
central MD. There is some potential for a storm or two to become
severe, with damaging winds and hail as the main threats.
The main surge is expected to develop by mid afternoon as the strong
synoptic forcing arrives, and is enhanced by the existing terrain
circulation and lee-side pressure trough. Models are rather good
agreement on timing, indicating numerous storms developing west of
the Blue Ridge between 2PM-3PM. These initial semi-discrete/cluster
storms could pose a large hail threat, in addition to damaging wind
gusts and a tornado or two. These storms move east of the Blue Ridge
between 4PM-5PM, and likely congeal into a solid/quasi-solid line
that reaches the I-95 corridor between 6PM-7PM.
This QLCS will be capable of producing widespread damaging wind
gusts, in addition to the possibility of embedded QLCS tornadoes.
Tornadoes that develop within these squall lines typically have
little lead time due to their rapid genesis. It is important to take
immediate action if a Tornado Warning is issued for your area. The
hail threat should diminish as the line of storms pushes eastward.
Finally, as the main mid-level trough moves over our area it could
initiate an additional broken line of showers and thunderstorms
later this evening. A low-level jet will have developed by that
time, and model soundings respond to the increasing low-level shear
with very wide hodographs, especially east of the Blue Ridge. There
will be a conditional tornado threat that lasts past sunset, and
given the strong shear, it won't take much instability for these
storms to intensify.
Be sure you have multiple ways of receiving severe weather alerts
today, and take immediate action if a severe thunderstorm or tornado
warning is issued for your location.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
The base of a strong mid-level trough will be right over our area
Tuesday morning. The trough shifts eastward over the Atlantic by
Tuesday night as a weak cold front sweeps through the area. Some
early day upslope showers are possible in the Alleghenies, and some
could spill east across the northern Shenandoah Valley into northern
MD. Otherwise, it looks to be mostly dry elsewhere. Afternoon highs
Tuesday are forecast to be in the low to mid 80s.
Dry and less humid conditions are expected Wednesday as a surface
high pressure moves across the region. Afternoon temperatures will
be a few degrees warmer, in the mid to upper 80s.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
Another round of strong to severe thunderstorms remains possible
Thursday into Friday. Additional precipitation chances for the
weekend ahead.
Synoptically, the upper level trough remains over the region with
quasi-zonal flow aloft. Some uncertainty remains within the timing
and magnitude of shortwave disturbances during the Thursday through
Saturday timeframe. Confidence is moderate for a more robust upper
level shortwave impacting the area from the Great Plains region
Thursday with northern stream shortwave energy for the weekend. As a
result, expect increased chances for showers and thunderstorms each
afternoon with temperatures remaining at or slightly above average.
For Thursday, 12z deterministic/ensemble guidance continues to show
a warm front lifting in from the south with robust upper level
shortwave energy quickly traversing the region. The guidance seems
to target central and southwest Virginia for the heaviest convective
probabilities compared to areas further north. Regardless GEFS/EPS
ensemble members continue to show a high probability of CAPE values
in exceedance of 500-1000 j/kg and 0-6km bulk effective shear values
on the order of 25-40 kts, especially in central and southern VA.
These values are slightly less further north due to the proximity of
the front and varying placement of the shortwave as it pushes toward
the region. Meanwhile, recent CSU Machine Learning Probabilities
suggest a marginal risk for severe weather especially across the
central Virginia Piedmont, southern Shenandoah Valley, eastern
Virginia, southwest Maryland, southwest Virginia. With that said,
confidence remains moderate for strong to severe thunderstorms
across southern portions of the forecast area Thursday into Thursday
night.
By Friday, the system departs the region. We get in a bit of lull
per the latest guidance as the piece of shortwave energy dives south
into the region. The forecast still remains fuzzy in regards to
timing and magnitude of this system with the bulk of guidance
suggesting a more subtle piece of energy compared to THursday and
the earlier part of the workweek. The upper level trough as a whole
look less amplified as well during weekend into early next week.
Even with that said, went ahead and kept 20-30 percent PoPs through
the weekend. The bulk of this will be during the peak heating period
of the afternoon and evening hours. Highest confidence for
precipitation would be over the mountains where better convergence
can be found compared to areas further east. Once again though this
will be dictated by the timing of shortwave energy and the
associated fronts as they push through. Temperatures will remain at
or slightly below normal late week with high in the mid to upper 80s
and low 90s. Overall confidence in the forecast for the Friday
through Sunday timeframe remains low though due in part to the
remaining differences between the models yet to be resolved. Stay
tuned!
&&
.AVIATION /14Z MONDAY THROUGH FRIDAY/...
The low stratus continues to impact all terminals outside of
KMRB. These borderline IFR/MVFR ceilings should improve within
the next hour or two as heating ensues.
Widespread showers and thunderstorms are expected to develop this
afternoon, with storms merging into a line east of the Blue Ridge.
Many of these storms will be strong to severe, with damaging wind
gusts, hail, and tornadoes possible. The high res guidance was in
good agreement on timing, so went ahead and added high-impact TEMPO
groups to all the TAFs at 06Z. Some refinement in timing might be
needed, but not by more than an hour on either side of the window.
Lingering -TSRA is expected behind the line of storms for a couple
of hours. Guidance is indicating MVFR CIGs at most terminals for
part of the night, but confidence is not high enough to go more than
BKN030 at this time.
Drier air filters in tonight, with conditions improving late tonight
into Tuesday morning as a cold front sweeps through the area. Mostly
dry conditions expected Tuesday, with WNW to NW winds gusting to
25KT into Tuesday night. VFR conditions are expected Wednesday.
Sub-VFR restrictions look to return especially at terminals south of
I-66/US-50 Thursday into Friday. This is in association with a warm
front lifting into the region. Showers and thunderstorms will
accompany the boundary Thursday afternoon and evening. VFR
conditions are expected otherwise with additional shower and
thunderstorm chances Friday into the weekend.
&&
.MARINE...
Increasing southerly winds will result in SCA conditions over all of
the waters by this afternoon, which continues into tonight. Numerous
strong to severe thunderstorms are expected to cross the local
waters late this afternoon into this evening. Wind gusts greater
than 50KT, large hail, and waterspouts will be possible.
A cold front is expected to sweep across the local waters tonight,
with SCA conditions developing tonight into Tuesday night as winds
gust up to 25-30KT. Winds decrease to below SCA levels Wednesday
morning as high pressure builds over the region. However, some parts
of the bay could still have wind gusting up to 20KT through
Wednesday evening.
SCA conditions are possible Thursday into Friday as another front
approaches from the south. These conditions will linger into the
weekend as additional fronts and tightened pressure gradient remain
over the region.
&&
.TIDES/COASTAL FLOODING...
Increased southerly flow combined with a tightening pressure
gradient from developing low pressure over the eastern Great Lakes
will result in coastal flooding concerns during the next 2 high
tide cycles. Coastal Flood Advisories have been issued for Havre de
Grace and Annapolis this morning and will likely be needed again for
the upcoming high tide cycles.
Many sites along the Western Shore are forecast to reach Action
Stage during the high tides through tonight. Annapolis and DC SW
Waterfront could reach minor flood tonight, and several other sites
could reach minor flood, as well.
A cold front that sweeps through the area Monday night will cause
winds to become northwest, causing tidal anomalies to drop Tuesday
and Wednesday.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...Coastal Flood Advisory until 4 PM EDT this afternoon for
DCZ001.
Coastal Flood Advisory from 11 PM this evening to 4 AM EDT
Tuesday for DCZ001.
MD...Coastal Flood Advisory until 2 AM EDT Tuesday for MDZ014.
Coastal Flood Advisory until 5 PM EDT this afternoon for
MDZ508.
Coastal Flood Advisory from 1 AM to 7 AM EDT Tuesday for
MDZ508.
VA...None.
WV...None.
MARINE...Small Craft Advisory until 8 PM EDT Tuesday for ANZ530>534-537-
541-543.
Small Craft Advisory until 8 PM EDT Tuesday for ANZ535-536-
538>540-542.
&&
SYNOPSIS...EST
NEAR TERM...BRO/KRR
SHORT TERM...KRR
LONG TERM...EST
AVIATION...BRO/KRR/EST
MARINE...KRR/EST
TIDES/COASTAL FLOODING...ESTHazardous Weather Outlook National Weather Service Baltimore MD/Washington DC 1034 AM EDT Mon Aug 7 2023 ANZ530>543-DCZ001-MDZ008-011-013-014-016>018-504-506-508- VAZ053>057-527-081445- Chesapeake Bay north of Pooles Island MD- Chesapeake Bay from Pooles Island to Sandy Point MD- Chesapeake Bay from Sandy Point to North Beach MD- Chesapeake Bay from North Beach to Drum Point MD- Chesapeake Bay from Drum Point MD to Smith Point VA- Tidal Potomac from Key Bridge to Indian Head MD- Tidal Potomac from Indian Head to Cobb Island MD- Tidal Potomac from Cobb Island MD to Smith Point VA- Patapsco River including Baltimore Harbor- Chester River to Queenstown MD-Eastern Bay- Choptank River to Cambridge MD and the Little Choptank River- Patuxent River to Broomes Island MD- Tangier Sound and the inland waters surrounding Bloodsworth Island-District of Columbia-Cecil-Southern Baltimore- Prince Georges-Anne Arundel-Charles-St. Marys-Calvert- Central and Southeast Montgomery-Central and Southeast Howard- Southeast Harford-Fairfax-Arlington/Falls Church/Alexandria- Stafford-Spotsylvania-King George- Central and Southeast Prince William/Manassas/Manassas Park- 1034 AM EDT Mon Aug 7 2023 This Hazardous Weather Outlook is for the Maryland portion of the Chesapeake Bay, Tidal Potomac River, and I-95 corridor through central Maryland, northern Virginia, and District of Columbia. .DAY ONE...Today and Tonight Numerous severe thunderstorms are expected to develop this afternoon and evening. Damaging winds will be the primary threat, some of these winds may become locally destructive. Additionally, a few tornadoes and large hail are possible. Isolated instances of flooding are also possible. .DAYS TWO THROUGH SEVEN...Tuesday through Sunday No hazardous weather is expected at this time. .SPOTTER INFORMATION STATEMENT... Spotters should activate for expected severe weather this afternoon and evening. Please relay reports to the National Weather Service in Sterling, Virginia. MDZ003>006-503-505-507-VAZ025>031-036>040-050-051-501-502-505>508- 526-WVZ050>053-055-081445- Washington-Frederick MD-Carroll-Northern Baltimore- Northwest Montgomery-Northwest Howard-Northwest Harford-Augusta- Rockingham-Shenandoah-Frederick VA-Page-Warren-Clarke-Nelson- Albemarle-Greene-Madison-Rappahannock-Orange-Culpeper- Northern Fauquier-Southern Fauquier-Western Loudoun- Eastern Loudoun-Northern Virginia Blue Ridge- Central Virginia Blue Ridge-Northwest Prince William-Hampshire- Morgan-Berkeley-Jefferson-Hardy- 1034 AM EDT Mon Aug 7 2023 This Hazardous Weather Outlook is for portions of eastern West Virginia, northern and central Virginia, and central and western Maryland. .DAY ONE...Today and Tonight Numerous severe thunderstorms are expected to develop this afternoon and evening. Damaging winds will be the primary threat, some of these winds may become locally destructive. Additionally, a few tornadoes and large hail are possible. Isolated instances of flooding are also possible. .DAYS TWO THROUGH SEVEN...Tuesday through Sunday No hazardous weather is expected at this time. .SPOTTER INFORMATION STATEMENT... Spotters should activate for expected severe weather this afternoon and evening. Please relay reports to the National Weather Service in Sterling, Virginia. MDZ001-501-502-VAZ503-504-WVZ501>506-081445- Garrett-Extreme Western Allegany-Central and Eastern Allegany- Western Highland-Eastern Highland-Western Grant-Eastern Grant- Western Mineral-Eastern Mineral-Western Pendleton- Eastern Pendleton- 1034 AM EDT Mon Aug 7 2023 This Hazardous Weather Outlook is for the Allegheny Front counties in western Maryland, eastern West Virginia, and Highland County Virginia. .DAY ONE...Today and Tonight Numerous severe thunderstorms are expected to develop this afternoon and evening. Damaging winds will be the primary threat, some of these winds may become locally destructive. Additionally, a few tornadoes and large hail are possible. Isolated instances of flooding are also possible. .DAYS TWO THROUGH SEVEN...Tuesday through Sunday No hazardous weather is expected at this time. .SPOTTER INFORMATION STATEMENT... Spotters should activate for expected severe weather this afternoon and evening. Please relay reports to the National Weather Service in Sterling, Virginia.
Special Weather Statement National Weather Service Baltimore MD/Washington DC 1205 PM EDT Mon Aug 7 2023 ANZ530>543-DCZ001-MDZ001-003>006-008-011-013-014-016>018-501>508- VAZ025>031-036>040-050-051-053>057-501>508-526-527-WVZ050>053-055- 501>506-071800- Chesapeake Bay north of Pooles Island MD- Chesapeake Bay from Pooles Island to Sandy Point MD- Chesapeake Bay from Sandy Point to North Beach MD- Chesapeake Bay from North Beach to Drum Point MD- Chesapeake Bay from Drum Point MD to Smith Point VA- Tidal Potomac from Key Bridge to Indian Head MD- Tidal Potomac from Indian Head to Cobb Island MD- Tidal Potomac from Cobb Island MD to Smith Point VA- Patapsco River including Baltimore Harbor- Chester River to Queenstown MD-Eastern Bay- Choptank River to Cambridge MD and the Little Choptank River- Patuxent River to Broomes Island MD- Tangier Sound and the inland waters surrounding Bloodsworth Island-District of Columbia-Garrett-Washington-Frederick MD- Carroll-Northern Baltimore-Cecil-Southern Baltimore- Prince Georges-Anne Arundel-Charles-St. Marys-Calvert- Extreme Western Allegany-Central and Eastern Allegany- Northwest Montgomery-Central and Southeast Montgomery- Northwest Howard-Central and Southeast Howard-Northwest Harford- Southeast Harford-Augusta-Rockingham-Shenandoah-Frederick VA-Page- Warren-Clarke-Nelson-Albemarle-Greene-Madison-Rappahannock-Orange- Culpeper-Fairfax-Arlington/Falls Church/Alexandria-Stafford- Spotsylvania-King George-Northern Fauquier-Southern Fauquier- Western Highland-Eastern Highland-Western Loudoun-Eastern Loudoun- Northern Virginia Blue Ridge-Central Virginia Blue Ridge- Northwest Prince William- Central and Southeast Prince William/Manassas/Manassas Park- Hampshire-Morgan-Berkeley-Jefferson-Hardy-Western Grant- Eastern Grant-Western Mineral-Eastern Mineral-Western Pendleton- Eastern Pendleton- Including the cities of Washington, Mountain Lake Park, Oakland, Grantsville, Hagerstown, Frederick, Ballenger Creek, Eldersburg, Westminster, Reisterstown, Cockeysville, Elkton, Baltimore, Bowie, Suitland-Silver Hill, Clinton, College Park, Greenbelt, Laurel, Camp Springs, Glen Burnie, Annapolis, Severn, South Gate, Severna Park, Arnold, Odenton, St. Charles, Waldorf, Lexington Park, California, Chesapeake Beach, Huntingtown, Dunkirk, North Beach, Lusby, Prince Frederick, Frostburg, Cumberland, Germantown, Damascus, Bethesda, Rockville, Gaithersburg, Silver Spring, Lisbon, Columbia, Ellicott City, Jarrettsville, Aberdeen, Staunton, Waynesboro, Stuarts Draft, Harrisonburg, Strasburg, Woodstock, Mount Jackson, New Market, Winchester, Luray, Shenandoah, Stanley, Front Royal, Berryville, Lovingston, Charlottesville, Stanardsville, Madison, Orange, Gordonsville, Culpeper, Reston, Herndon, Annandale, Centreville, Chantilly, McLean, Franconia, Arlington, Alexandria, Falls Church, Falmouth, Fredericksburg, Dahlgren, Warrenton, Turnbull, Hightown, Monterey, Purcellville, Leesburg, Ashburn, Sterling, Big Meadows, Wintergreen, Haymarket, Dale City, Manassas, Woodbridge, Lake Ridge, Montclair, Romney, Paw Paw, Martinsburg, Charles Town, Shepherdstown, Moorefield, Bayard, Mount Storm, Petersburg, Elk Garden, Antioch, Keyser, New Creek, Ridgeville, Russelldale, Headsville, Fort Ashby, Riverton, Brandywine, Franklin, Oak Flat, Ruddle, and Sugar Grove 1205 PM EDT Mon Aug 7 2023 ...SEVERE WEATHER OUTBREAK EXPECTED OVER THE MID-ATLANTIC REGION BETWEEN 2 PM AND 10 PM TODAY, INCLUDING THE GREATER BALTIMORE/WASHINGTON METROPOLITAN AREAS... An outbreak of severe storms is expected this afternoon and evening across the greater Baltimore/Washington region, with numerous severe thunderstorms expected. There is a significant threat for damaging and locally destructive hurricane-force winds, along with the potential for large hail and tornadoes, even strong tornadoes. The timing of this outbreak varies with your location. West of the Blue Ridge Mountains, you can expect the storms to arrive between 12 Noon and 3 PM. East of the Blue Ridge Mountains, timing will be from 4 PM to 8 PM. The greater Baltimore/Washington Metropolitan Areas can expect the storms to arrive between 5 PM and 7 PM. Now is the time to review your severe weather safety procedures for the possibility of dangerous weather today. Do not be outdoors when the storms arrive. When you hear thunder, go indoors to a sturdy building or structure. While seeking shelter indoors, go to the lowest floor to an interior room. Stay away from windows. Those in mobile homes or weaker structures should plan ahead of time to shelter in a stronger shelter. Be prepared for extended power outages, and the potential for some roads to be blocked by fallen trees. For the after-event cleanup, do not go outside until 30 minutes after you hear the last thunder, otherwise you will be still susceptible to lightning strikes. Be aware of downed power lines and unstable branches and trees. Stay tuned to NOAA Weather Radio, weather.gov, or other media for watches and warnings. If a Severe Thunderstorm Warning or Tornado Warning is issued for your area, move to a place of safety, ideally in an interior room on the lowest level of a sturdy building. LEE/STRONG
The Pittsburgh radar (KPBZ), 124 km away, was scanning. The volume nearest the first event began at 17:35 UTC.
62 thunderstorm wind, 14 hail. Local standard time, as filed.
Multiple trees blew down on MD-42 Friendsville Road, closing the roadway.
Trees and power lines blew down on Gravelly Run Road.
Trees blew down on Foster Road.
Numerous trees blew down between McHenry and Friendsville.
Two-inch diameter hail was reported between McHenry and Bittinger.
Quarter size hail was reported in the 12900 block of Draper Road.
Dung Hill Road was closed due to downed trees.
Numerous trees and wires blew down around Accident, closing many roads.
There were a couple of reports of hail up to ping pong ball size in the North Glade area of Swanton.
Half dollar size hail was reported in the 12900 block of Draper Road.
Softball size hail was reported north of Clear Spring.
Two-inch diameter hail was reported on Saint Paul Road just south of I-70 Dwight D. Eisenhower Highway.
Considerable wind damage was reported along of MD-135 Maryland Highway between Swanton and Luke. Many roads in the area were closed due to downed trees and wires.
Savage River Road was closed due to downed trees.
Hundreds of trees blew down near Lonaconing. Most roads in the area were impassable.
Several roads were closed due to downed trees between Mount Savage and Frostburg toward the Garrett County line.
Trees blew down near the intersection of Ernstville Road and MD-56 Big Pool Road.
Several trees blew down around La Vale.
Quarter size hail was reported at Hagerstown Regional Airport.
Several trees, branches and wires blew down in Cumberland resulting in a few road closures.
Numerous trees blew down blocking roadways between Flintstone and Oldtown.
Two-inch diameter hail was reported in Williamsport.
Trees blew down in Little Orleans, closing roads.
Quarter size hail was reported on the northwest side of Hagerstown.
Golf ball size hail was reported off of Alternate US-40 Old National Pike near Funkstown.
Quarter size hail was reported in the 18600 block of Orchard Hills Parkway.
Trees blew down on MD-66 Mapleville Road near I-70 Dwight D. Eisenhower Highway.
Ping pong ball size hail was reported on MD-66 Mapleville Road near I-70 Dwight D. Eisenhower Highway.
Two-inch diamter hail was reported in the 100 block of Vody's Court.
Two-inch diamter hail was reported in the 23700 block of MD-77 Foxville Road.
Dozens of trees, wires and poles blew down in Clear Spring. Many roads were impassable.
Tree damage was reported near Thurmont, including a tree that blew down near the intersection of Apple Church Road and Carol Street.
Several trees, branches and power lines blew down between Hagerstown, Clear Spring and Williamsport.
Trees blew down onto power lines in the 3900 block of Wistman Lane.
A wind gust of 55 knots (63 MPH) was measured by the AWOS at Camp David (KRSP).
Trees blew down onto the roadway near the intersection of MD-76 Motters Station Road and Mumma Ford Road/Appolds Road.
Trees blew down on MD-180 Jefferson Pike near US-15/340.
There were nearly 100 calls for trees and wires blown down throughout Frederick County, Maryland, most focused east and northeast of the city of Frederick just after 4:30 PM EDT.
Trees blew down near the intersection of MD-550 Creagerstown Road and Graceham Road.
Numerous large trees down and snapped including one onto a house in the 2600 block of Thurston Road near Dixon Road.
Dozens of trees, wires and poles blew down near Woodsboro.
A wind gust of 70 knots (80 MPH) was measured by a personal weather station near the intersection of Sharrett Road and Crouse Mill Road in Middleburg. Dozens of trees, branches and wires blew down in the area.
Numerous trees blew down in the 6700 block of Oakridge Court, including at least one onto a house. Numerous trees blew down near the intersection of MD-75 Green Valley Road and Ed McClain Road.
Several trees and wires blew down in the 200 block of South Springdale Road.
Thousands of trees, branches and wires blew down near Union Mills. Numerous trees blew down along MD-97 Littlestown Pike, including several large trees near Mayberry Road. Dozens of roads in the area were blocked by storm debris for several days. Several barns were destroyed. Several homes suffered minor roof, shingle and siding damage.
Thousands of trees, branches and wires blew down near and north of Westminster. 30 utility poles snapped along MD-97/MD-140 Baltimore Boulevard near Gorsuch Road, with live wires trapping several people in their vehicles for a few hours; two people were injured. Dozens of roads in the area were blocked by storm debris for several days. Several homes suffered minor roof, shingle and siding damage. Several barns were destroyed.
Trees and wires blew down on MD-109 Old Hundred Road at Peach Tree Road.
Wind gusts of up to 66 knots (76 MPH) was measured by a mesonet at the Carroll County Government offices in the 200 block of North Center Street.
Trees blew down near Carroll Community College.
A large tree blew down into the roadway in the 24000 block of River Road.
Several trees blew down along MD-97 Old Washington Road at the Carroll/Howard County line.
Trees blew down across MD-144 Frederick Road near MD-97 Roxbury Mills Road.
Hundreds of trees, branches and wires blew down and snapped around Manchester and Hampstead, including many onto cars and houses. Dozens of roads were blocked by storm debris for several days. Several homes suffered minor roof, shingle and siding damage. Several barns were destroyed. Numerous trees blew down near the intersection of White Oak Court and Ebbvale Road. Power poles blew down into trees near the intersection of Ralph Dell Road and Cape Horn Road.
Dozens of trees, branches and wires blew down around Eldersburg, blocking several roads for up to a day.
Dozens of trees blew down in the Lineboro area along the Pennsylvania state line.
Dozens of trees blew down in Glenwood and Lisbon.
Numerous trees blew down in Sykesville, including at least one onto a house.
Numerous trees blew down in the Hampstead area, including one onto a house causing an injury in the 2100 block of Moonlight Drive.
Dozens of trees, branches and wires blew down in the Finksburg area.
Trees blew down on MD-26 Liberty Road to the west of Lyons Mill Road.
A wind gust of 55 knots (63 MPH) was measured by a personal weather station at a Co-op Observer's residence.
Dozens of trees blew down around Parkton and Freeland. Trees blew down in the 19000 block of MD-45 York Road, including one onto a house.
Dozens of trees blew down in northeastern Baltimore County, including one onto a car on southbound I-83 at Exit 36/MD-439 Old York Road.
Thousands of large trees and wires blew down and snapped west of Jarrettsville, including several trees that blew onto a house in the 3100 block of MD-138 Troyer Road. Trees blew down onto a house in the 2900 block of MD-138 Troyer Road, injuring one person. Hundreds of trees blew down and snapped along Rock Ridge Road; almost all trees along this road were either toppled, or lost a signficant amount of branches.
A large tree blew down onto a structure in the 12300 block of Timber Grove Road.
Several trees blew down near the intersection of McDonogh Road and Winands Road.
Numerous trees blew down in Rockville, including one onto a house in the 900 block of Grandin Avenue.
Numerous trees blew down near Chrome Hill, including near the intersection of Sharon Road and Rock Spring Road.
A tree blew down onto a structure in the 1300 block of Sudvale Road.
Dozens of trees blew down near Hickory, including one onto a house trapping a resident on Glendale Lane. Trees blew down onto wires bringing down a power pole near the intersection of MD-543 North Fountain Green Road and Prospect Mill Road.
Dozens of trees blew down near Pylesville and Churchville, including on MD-543 Ady Road near Doyle Road. Several trees blew down into the roadway near the intersection of MD-136 Priestford Road and Northern Dancer Drive.
Hundreds of trees and large branches blew down around West Nottingham, including along Norman Road.
Numerous trees blew down along MD-273 Rising Sun Road in northern Cecil County between Rising Sun and Fair Hill. Numerous trees blew down on nearby roadways, as well.
Trees blew down near the intersection of MD-7 East Cecil Avenue and Mechanics Valley Road.
Trees blew down near the intersection of MD-273 Telegraph Road and Appleton Road.
Trees and power lines blew down around Davidsonville.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Maryland in 2023Every state in 2023This day in weather historyWarnings in Maryland, August 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: 1108472, 1108473, 1108474, 1108475, 1108476, 1108477, 1108478, 1108479, 1108480, 1108481, 1108482, 1108483, 1108484, 1108485, 1108486, 1108487, 1108488, 1108489, 1108490, 1108491, 1108506, 1108509, 1108510, 1108513, 1108514, 1108518, 1108519, 1108520, 1108522, 1108526, 1108533, 1108534, 1108542, 1108554, 1108558, 1108564, 1108565, 1108566, 1108567, 1108571, and more.