Low pressure moved through the Great Lakes during the day of April 12th while a cold front slowly approached the Mid-Atlantic from the west. Low level easterly flow turned southerly and warmer and more humid air moved into the region.
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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 LWX wrote it up.
Low pressure moved through the Great Lakes during the day of April 12th while a cold front slowly approached the Mid-Atlantic from the west. Low level easterly flow turned southerly and warmer and more humid air moved into the region. This increasing moisture and instability and a strengthening wind field led to the development of showers and scattered thunderstorms across portions of the state, one of which became severe in western Maryland.
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 Apr 12, 1:52 PM EST, 2 hours 34 minutes earlier.
Area Forecast Discussion National Weather Service Baltimore MD/Washington DC 252 PM EDT Fri Apr 12 2019 .SYNOPSIS...A cold front will approach the area tonight and it will weaken as it moves overhead overnight through Saturday. A strong area of low pressure will move from the Midwest to the Great Lakes Sunday into Sunday night. A strong cold front associated with this low will move through the region Sunday night into Monday. High pressure is expected to build overhead later Monday through the middle portion of next week. && .NEAR TERM /THROUGH TONIGHT/... Showers east of the Blue Ridge mtns have been occurring on the nose of a low-level moisture plume and 850 mb low level jet that extends from off of Southeast coast across the Carolinas into southern VA. Some convective elements have been observed with the shra activity currently over the Chesapeake Bay. The low- levels still remain stable as evidenced by lack of gustiness on sfc winds away from the water, but the increasing warmth and moisture advection could lead to elevated t-storms about any time. A line of showers and isolated t-storms also extends from Michigan south through OH into KY and TN. This is associated with a weakenning frontal zone, this activity is expected to reach the crest of the Appalachians around 00Z tonight. The approaching frontal zone and continued moisture advection will keep the risk of showers and thunderstorms high through much of the night (~09-10Z) especially east of I-81. T-storms are expected to remain non-severe, but could produce locally heavy rainfall. Given dry antecedent conditions, most areas should be able to handle most of the rainfall tonight. While it will be an active night, no hazardous weather is expected other than lightning. The front will stall over the area early Sat with showers tapering off or exiting to the southeast around daybreak. && .SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/... The front will stall south of the area Sat with the majority of the shra activity remaining to the south of our CWA. Any showers will likely depend on areas that receive the most heating. Otherwise, expect plenty of mid-high level clouds. Things should remain relatively quiet through Sun morning. Then, deepening low pressure system over the OH valley will bring another round of widespread showers and thunderstorms late Sun through Sun night. Some storms may become severe given strengthening wind fields and unstable conditions. Isolated tornadoes are also possible assuming sufficient instability develops ahead of main convective line along frontal zone. While the t-storm activity will likely persist through much of the night, the most intense should occur between 21Z Sun-03Z Mon. Showers will end quickly by daybreak Mon with frontal passage. && .LONG TERM /MONDAY THROUGH FRIDAY/... Rain showers could linger into late Monday morning, but should clear much of the area by the afternoon. The one exception will be some lingering upslope rain/snow showers along/west of the Allegheny Front as a gusty northwest flow takes over. Temperatures will be cooler Monday, with highs in the mid 60s. Main concern on Monday will be gusty NW winds behind the cold front, which could warrant Wind Advisories, but for now that does look pretty marginal at this time. A quiet weather pattern will continue through around Thursday, as high pressure slides by to the south, eventually off the southeast coast Wednesday into Thursday. This will result in dry weather, and increasing temperatures through Thursday. Highs on Tuesday will reach the mid to upper 60s. Wednesday and Thursday will be much warmer, with highs in the 70s as high pressure pushes offshore, bringing warm and moist southerly flow to the region once again. Meanwhile, a vigorous upper trough will eject out of the southwestern US and into the Great Lakes or Ohio Valley regions Wednesday night through late Thursday. A strong surface low will form in response to this upper level system and track towards our area by late Thursday or Friday. Timing is not nailed down just yet, but this system will bring showers and thunderstorms to the region sometime late in the week. This system has the potential to bring another chance for some strong to severe thunderstorms as well, given a warm and moist environment and favorable shear profiles. Stay tuned for updates as we get closer to this storm system. && .AVIATION /19Z FRIDAY THROUGH WEDNESDAY/... Sub-VFR conditions could linger into Monday morning with some showers still around. VFR conditions return by Monday afternoon, as the cold front clears the area and will remain through much of Thursday. Gusty NW winds are expected Monday afternoon behind the cold front, with gusts to 25-35 knots. && .MARINE... SCA conditions expected through tonight with winds diminishing Sat as frontal zone sinks south. Winds strengthen Sun ahead of strong low pressure system with potential for gales and severe thunderstorms Sun night. Strong post-frontal winds will likely persist through Monday before diminishing Mon night. Small Craft Advisories are likely on Monday, as a cold front pushes through the area and gust NW winds return. Gale Warnings may even be needed Monday afternoon. Gusty winds continue into Tuesday as well, with Small Craft Advisories likely needed once again. && .TIDES/COASTAL FLOODING... Water levels will remain elevated into Sat morning due to increasing surge due to gusty srly winds. At this time, most sites are expected to remain below minor coastal flooding except at DC Waterfront. No advisories are plannned at this time. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...None. MD...None. VA...None. WV...None. MARINE...Small Craft Advisory until 6 AM EDT Saturday for ANZ530>543. && SYNOPSIS...LFR NEAR TERM...LFR SHORT TERM...LFR LONG TERM...CJL AVIATION...LFR/CJL MARINE...LFR/CJL TIDES/COASTAL FLOODING...LFR
Hazardous Weather Outlook National Weather Service Baltimore MD/Washington DC 407 PM EDT Fri Apr 12 2019 ANZ530>543-DCZ001-MDZ011-013-014-016>018-508-VAZ052>057-131000- 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-Southern Baltimore-Prince Georges- Anne Arundel-Charles-St. Marys-Calvert-Southeast Harford- Prince William/Manassas/Manassas Park-Fairfax- Arlington/Falls Church/Alexandria-Stafford-Spotsylvania- King George- 407 PM EDT Fri Apr 12 2019 This Hazardous Weather Outlook is for the Maryland portion of the Chesapeake Bay, Tidal Potomac River, and adjacent counties in central Maryland and northern Virginia as well as the District of Columbia. .DAY ONE...This Afternoon and Tonight Showers and thunderstorms may produce isolated instances of flooding this evening and tonight. A severe thunderstorm with damaging wind gusts is also possible, mainly across central Virginia. .DAYS TWO THROUGH SEVEN...Saturday through Thursday A few thunderstorms may become severe late Sunday through Sunday night with damaging winds being the primary threat. However, a tornado cannot be ruled out. Some storms may also produce heavy rain that could lead to flooding Sunday night through early Monday. A Gale Warning may be needed for portions of the waters Monday and Monday night. .SPOTTER INFORMATION STATEMENT... Spotter activation is not expected at this time. MDZ003>006-501>507-VAZ025>031-036>040-050-051-501>508-WVZ050>053- 055-501>506-131000- Washington-Frederick MD-Carroll-Northern Baltimore- Extreme Western Allegany-Central and Eastern Allegany- Northwest Montgomery-Central and Southeast Montgomery- Northwest Howard-Central and Southeast Howard-Northwest Harford- Augusta-Rockingham-Shenandoah-Frederick VA-Page-Warren-Clarke- Nelson-Albemarle-Greene-Madison-Rappahannock-Orange-Culpeper- Northern Fauquier-Southern Fauquier-Western Highland- Eastern Highland-Western Loudoun-Eastern Loudoun- Northern Virginia Blue Ridge-Central Virginia Blue Ridge- Hampshire-Morgan-Berkeley-Jefferson-Hardy-Western Grant- Eastern Grant-Western Mineral-Eastern Mineral-Western Pendleton- Eastern Pendleton- 407 PM EDT Fri Apr 12 2019 This Hazardous Weather Outlook is for eastern West Virginia, northern and central Virginia, and central and western Maryland with the exception of Garrett County. .DAY ONE...This Afternoon and Tonight There is an isolated threat for thunderstorms to produce locally damaging wind gusts this evening. Localized flooding is also possible during this time. .DAYS TWO THROUGH SEVEN...Saturday through Thursday A few thunderstorms may become severe Sunday afternoon and Sunday night with damaging winds being the primary threat. However, a tornado cannot be ruled out. Some storms may also produce heavy rain that could lead to flooding Sunday night through early Monday. .SPOTTER INFORMATION STATEMENT... Spotter activation is not expected at this time.
The Sterling radar (KLWX), 126 km away, was scanning. The volume nearest the first event began at 21:25 UTC.
2 thunderstorm wind. Local standard time, as filed.
A tree was blown down near the intersection of Maryland Route 51 Oldtown Road Southeast and Moores Hollow Road Southeast.
A 40-foot tree was blown down across US-220 McMullen Highway near North Cresap Street.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Maryland in 2019Every state in 2019This day in weather historyWarnings in Maryland, April 2019
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: 816625, 816627.