Ridging at the surface and aloft led to hot and humid conditions.
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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.
Ridging at the surface and aloft led to hot and humid conditions.
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 6, 9:39 AM EST, 1 hour 21 minutes earlier.
Area Forecast Discussion National Weather Service Baltimore MD/Washington DC 1039 AM EDT Mon Aug 6 2018 .SYNOPSIS... High pressure will remain over the western Atlantic through Tuesday while an upper-level high builds to the south. A cold front will approach the Mid-Atlantic late Tuesday into Wednesday before passing through Wednesday night. High pressure will briefly return for Thursday into Friday, but an upper-level trough may impact the area next weekend. && .NEAR TERM /THROUGH TONIGHT/... Light winds and mainly clear skies dominate at present. For the rest of today, the subtropical ridge will remain southeastern CONUS while surface high pressure remains over the Atlantic. A weak upper-level low overhead early this morning will move off to our east today. A light southerly flow around the surface high and higher heights from the subtropical ridge will once again lead to hot and humid conditions along with sunshine. Latest guidance progs 925-850mb temps similar to yesterday so max temps are expected to be in the lower to middle 90s for most areas. Heat indices around 100 degrees are likely near the I-95 corridor toward the Bay. The heat and humidity will lead to an unstable atmosphere, but there will still be a capping inversion that will be tough to erode. A weak pressure trough along with terrain circulation/bay and river breezes should be enough to produce convection. However, coverage should be isolated to scattered due to that capping inversion. The heat and humidity will lead to moderate to high amounts of instability above the capping inversion. Therefore, an isolated stronger storm with gusty winds/heavy rainfall cannot be ruled out later this afternoon/evening. Convection should wane this evening due to the loss of daytime heating, and more warm and humid conditions are expected overnight. Locally dense fog is possible overnight as well. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... A similar weather pattern is expected Tuesday through Tuesday night with the subtropical ridge to the south and high pressure over the Atlantic. More hot and humid conditions are expected with max temps in the 90s for many locations. Heat indices near 100 are possible, mainly east of the Blue Ridge Mountains. The heat and humidity will lead to more unstable conditions so popup showers and thunderstorms are possible during the afternoon and evening hours. Coverage may be a bit more than previous days since heights will be a bit lower in response to a cold front and upper-level trough upstream over the Great Lakes and Midwest. A few storms may produce gusty winds/heavy rain. The cold front will approach the area Wednesday before passing through Wednesday night. More hot and humid conditions are expected ahead of the front Wednesday. Showers are likely with possible thunderstorms later Wednesday into Wednesday evening ahead of the front. Gusty winds/heavy rain are possible in thunderstorms that develop. Convection should wane overnight as the cold front passes through the area and somewhat drier air advects in from the west. && .LONG TERM /THURSDAY THROUGH SUNDAY/... A cold front will be south/southeast of our CWA early on Thursday. Some showers are possible near that area of our CWA before the front moves away and stalls over the Carolinas. Guidance is suggesting that it may take a little longer to move away from us on Thursday. A weak high pressure builds in behind the front and remains in control into Friday allowing for drier conditions over the area. Trough aloft will be deepening Friday and into Saturday with a surface front approaching from the northwest. Guidance is in disagreement on the timing on when/if a cut-off low develops and its location, but they do agree with unsettled weather for the weekend. These conditions will allow for showers and thunderstorms development on Saturday and Sunday. && .AVIATION /15Z MONDAY THROUGH FRIDAY/... VFR all terminals at present. However, isolated to scattered showers and thunderstorms are expected this afternoon and evening. Convection should wane this evening but patchy fog is expected late tonight into Tuesday morning, and a few showers and thunderstorms are possible Tuesday afternoon and evening. An approaching cold front may bring a better chance for showers and thunderstorms Wednesday afternoon and evening before the cold front passes through overnight. Generally VFR conditions can be expected Thursday into Friday as front moves away and high pressure builds in. Restrictions may return Friday night into Saturday due to showers and thunderstorms development over our area. && .MARINE... South to southwest winds are expected through Wednesday, and channeling of southerly winds is possible during the nighttime and early morning hours. Winds may approach SCA criteria for portions of the Bay and lower Tidal Potomac River during these times, but confidence is low. Popup showers and thunderstorms are also expected for today and Tuesday, mainly during the afternoon and evening hours. Thunderstorms may be capable of producing gusty winds but the threat is isolated due to the limited coverage in storms. There is a better chance for showers and thunderstorms ahead of a cold front Wednesday afternoon through Wednesday evening. Convection should wane overnight as the boundary passes through the waters and winds switch to the west and northwest. Wind gusts will generally remain below SCA conditions Thursday and Friday as high pressure builds into our area. Showers and thunderstorms may return Friday night into Saturday with maybe some gusty winds. && .TIDES/COASTAL FLOODING... A south to southwest flow will cause elevated water levels through Wednesday. Water levels may approach minor flood thresholds during the overnight/morning high tides which is the higher of the two, but confidence is low since the flow will be light. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...None. MD...None. VA...None. WV...None. MARINE...None. && SYNOPSIS...BJL NEAR TERM...BJL/RCM SHORT TERM...BJL LONG TERM...IMR AVIATION...BJL/IMR/RCM MARINE...BJL/IMR TIDES/COASTAL FLOODING...BJL
Hazardous Weather Outlook National Weather Service Baltimore MD/Washington DC 503 AM EDT Mon Aug 6 2018 ANZ530>543-DCZ001-MDZ011-013-014-016>018-508-VAZ052>057-071000- 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- 503 AM EDT Mon Aug 6 2018 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...Today and Tonight No hazardous weather is expected at this time. .DAYS TWO THROUGH SEVEN...Tuesday through Sunday No hazardous weather is expected at this time. .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>506-071000- 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- 503 AM EDT Mon Aug 6 2018 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...Today and Tonight No hazardous weather is expected at this time. .DAYS TWO THROUGH SEVEN...Tuesday through Sunday No hazardous weather is expected at this time. .SPOTTER INFORMATION STATEMENT... Spotter activation is not expected at this time.
The national radar mosaic for the moment the first event began.
1 heat. Local standard time, as filed.
Heat indices were around 100 degrees. The Maryland Department of Health reported 2 fatalities occurring during the week.
As the offices recorded each death: direct deaths were caused by the weather itself, indirect ones by something it set in motion.
| Event | Date | Age | Sex | Where | Kind |
|---|---|---|---|---|---|
| Heat, Southern Baltimore | 2018-08-06 | Male | Unknown | Direct | |
| Heat, Southern Baltimore | 2018-08-06 | Unknown | Direct |
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Maryland in 2018Every state in 2018This day in weather historyWarnings in Maryland, August 2018
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: 777364.