Locally heavy rain showers produced as much as 2 to 5 inches of rain in parts of New Castle County on the afternoon of August 17.
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 PHI wrote it up.
Locally heavy rain showers produced as much as 2 to 5 inches of rain in parts of New Castle County on the afternoon of August 17.
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 Philadelphia/Mount Holly wrote its last area forecast discussion before the first event at Aug 17, 11:25 AM EST, 1 hour 50 minutes earlier.
Area Forecast Discussion National Weather Service Mount Holly NJ 1225 PM EDT Tue Aug 17 2021 .SYNOPSIS... High pressure will remain centered to our east over the next couple of days. Meanwhile, the remnants of Tropical Storm Fred will lift northward along the Appalachians through midweek, affecting our area on Wednesday into Thursday. An upper level disturbance moving slowly out of the Great Lakes will keep conditions unsettled through the weekend, before a cold front potentially arrives early next week. && .NEAR TERM /THROUGH TONIGHT/... Showers and downpours have primarily been confined to Delmarva and very far southeastern Pennsylvania. With one downpour moving out of Cecil County into New Castle County in particular having been the most impressive with several local gauges in far northwestern New Castle County estimating rainfall so far of 3-4 inches in a very small area. Thankfully, this has been the only concerning downpour thus far but we will closely monitor the chances with the potential for localized Flash Flood Watch or warning. No reports of flooding so far. CAMs continue to keep this activity mostly to the west of Philly, but a brief shower or two can't be entirely ruled out. Otherwise, bumped temps down a degree or two this afternoon with widespread cloud cover, especially across eastern PA. There are chances for showers and thunderstorms through today and tonight as a front inches closer to our region. As of early this morning, the front was currently stationary from northern WV to the eastern VA/NC state line. This front is still expected to slowly inch toward our region as a warm front as it weakens. Given that this is the only significant source of lift for our region (better synoptic scale lift should remain to our west today and tonight), there is uncertainty in how widespread showers and thunderstorms will be through tonight. However, for any showers and storms that develop, there is some risk for heavy rain. Thanks to the persistent onshore southeasterly flow, we already have plenty of moisture in the atmosphere, with 00Z RAOBs around the region showing precipitable water values between 1.7 and 2.3 inches, and dewpoints in the 60s across the region. Dewpoints and PWATs should only increase through the day with persistent low level onshore flow and by late today, mid level flow becomes favorable for moisture transport from what by that time should be the remnants of Fred (however, the main remnants of Fred will not be arriving until the short term - see that discussion below). Also concerning is that storm motions should be relatively slow today (20 mph or less). Having said that, have chosen not to issue a flood watch for today or tonight due to the potential for the sparsity of coverage. Additionally, for today and tonight, the more favored area for rain is west of the Delaware Valley where flash flood guidance is slightly higher. As for any other hazards, CAPE and shear values are limited, so the risk for severe winds and hail is low. However, of note is that there is more than usual directional shear in the lowest 3 km. given the relatively light winds through these levels, this doesn't make a big contribution to shear values. As for temperatures, the front will have little impact as the temperature gradient across the front should be relatively small by the time it arrives. Highs should be from the mid 70s to mid 80s, even with persistent cloud cover. The cloud cover and increasing dewpoints will mean temperatures won't drop off too much tonight, with lows mostly in the 70s (though some portions of E Central PA and NW NJ may get into the upper 60s. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... For the midweek period, the main forecast concern will be the impact of the remnants of Tropical Storm Fred on the area. A tropical air mass will reside over our region for most of this period, especially Wednesday, as PWAT values soar over 2 inches by later in the day. On Wednesday morning, the center of Fred is forecast to be in the area of West Virginia. Compared to a couple days ago, trends continue to be faster with bringing Fred northward, and it now looks like late Wednesday and Wednesday night will be our period of most impact. There remains some uncertainty with the distribution of QPF. Some guidance keeps the heaviest swath of rainfall mostly west of us, while some show a more substantial impact. Either way, steady/heavy rain should hold off for most of the day on Wednesday, though some pop-up showers are possible with the heating of the day in the tropical air mass. By Wednesday evening and night, that is when we will run the risk for heavier rainfall. Highest rainfall amounts will be over the western half of the region, tailing off towards the coast. But how strong that gradient is, and how high the maximum values in the western part of the region will be, are in question. The 17.00z GFS for instance would suggest little concern anywhere in the region, while the same cycle of the EC would yield considerable concern for flash flooding. Definitely not enough confidence at this stage for a Flash Flood Watch. However, if consensus trends towards the camp of models showing a more widespread 2 to 4 inches of rain in parts of our region, than one may eventually be required. Any time an environment such as this is in place, there is at least a conditional threat of heavy rainfall, so we will monitor closely. Outside of the rainfall forecast, with considerable cloud cover, temperatures on Wednesday will struggle towards and probably fall just shy of seasonal averages. However, with very high humidity, the day will be quite uncomfortable, with a muggy, tropical feel. Overnight lows will also fail to drop below 70 in many cases, another indicator of the tropical environment. One other item to watch: with our region being in a right-of-track position late Wednesday and Wednesday night, we may have to monitor for the risk of rotating cells and an isolated tornado threat. The SPC SWODY2 has added a Marginal Risk of severe weather for the region. Due to weak dynamic forcing, including the lack of any nearby synoptic frontal systems, this potential looks lower than normal with a tropical system. It also looks like instability will be quite limited. Nonetheless, this will at least be something to keep an eye on. By Thursday, what's left of Fred will be moving into New England. Surface winds will shift more westerly by afternoon, advecting slightly drier air into the region. It's possible Thursday could actually end up as one of our drier days of the next several, especially if Fred moves out quickly enough, as seems to be the overall trend. While an additional pop-up shower or storm can't be ruled out in the afternoon, we will probably get into some modest subsidence in the wake of Fred which could keep that risk lower. Have trended the PoPs to reflect lingering higher values in the morning but lower in the afternoon. Highs look similar to those on Wednesday, and overnight lows will again be on the mild side. With winds dropping off more than on Wednesday night, may have to deal with some fog development overnight. && .LONG TERM /FRIDAY THROUGH TUESDAY/... Overview... The synoptic pattern heading into the end of the week, the weekend, and early next week is rather unsettled. The overall tendency is for longwave troughing over the West and ridging in the East, but the presence of a weak upper level low over the Great Lakes and an abundance of tropical moisture over the eastern US and western Atlantic will make for a complex forecast. By Friday, the remnants of Tropical Storm Fred will have moved away from the area. In many cases of departing tropical cyclone remnants, a cold front will sweep away the tropical system and allow a drier air mass to prevail behind it. This will not be the case with Fred, as its remnants don't so much depart the area as they simply dissipate near and north of us in the face of upper level ridging. Because of this, the air mass remains moist and stagnant through the weekend with PWAT values remaining in the range of 1.5 to 2.0 inches and surface dew points in the upper 60s and low 70s. With slow moving upper level low pressure advancing from the Great Lakes, this will leave the door open for weakly forced, largely diurnally driven convection daily. Not expecting any washouts, but it will be the classic summertime "sun and storm" forecast with seasonably warm temperatures, high humidity, and hit or miss showers and storms. By early next week, a cold frontal passage may bring at least temporary relief from the humidity and lower rain chances. Dailies... Friday-Sunday... On paper, the forecast for these three days looks more or less identical. We remain in a modified tropical air mass with a diffuse surface pattern. This translates to a forecast of humid conditions with highs mostly in the mid to upper 80s, lows in the upper 60s to near 70, and daily rain chances of 30 to 50 percent, highest to the west. In reality, it's unlikely the days will be total carbon copies of one another, and in particular one or two will probably feature more widespread shower and storm activity than another. But they all look to fall within a similar pattern and given timing uncertainties and model differences it's best to keep things more general for now. With very weak shear, the severe weather threat is near zero through the period. Given the high PWATs, localized heavy rain will be possible, though it doesn't look like a widespread flash flood threat. Monday and beyond... By early next week, most indications are that a cold front will finally approach the region and bring an end to the high humidity. While the timing is subject to change, a current consensus would bring the front through around Monday, potentially with another threat of showers and storms, but would open the door for drier weather and lower humidity heading towards the middle of next week. && .AVIATION /16Z TUESDAY THROUGH SATURDAY/... The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY and surrounding areas. Today...Mostly prevailing VFR today, but MVFR will be more likely at KRDG and KABE, and possible ILG. There is a chance for showers and thunderstorms throughout the day, with the highest chances for KRDG and KABE. Winds should stay southeasterly at 5 to 10 kt through the day. High confidence on the wind forecast, low confidence on the details of the flight category forecast, including timing. Tonight...MVFR, and even some IFR, ceilings could move back in between 00 and 06Z. Chance for showers and thunderstorms decreases by remains 20 to 40 percent for the Delaware Valley westward. If any TAF sites see heavy rain today, localized BR may develop tonight. Southeasterly winds less than 5 kt. Moderate confidence on the overall pattern, but low confidence on timing details. Outlook... Wednesday-Wednesday night... Prevailing sub-VFR conditions are likely with low clouds, showers, and thunderstorms. Some areas, especially east/southeast of PHL, may be VFR for at least a good portion of the day on Wednesday. But by Wednesday afternoon and through the night, widespread MVFR/IFR is likely, and rain may be heavy at times. Winds southeast at 5 to 10 kt, becoming more southerly overnight. Moderate confidence. Thursday-Thursday night... Lingering sub-VFR into Thursday morning. However, improvement to prevailing VFR with only localized restrictions is looking more likely for the bulk of the day. Some patchy fog possible overnight. Winds southwest at 5 to 10 kt, becoming light and variable or calm overnight. Moderate confidence. Friday-Saturday... Prevailing VFR, but daily chances for showers and tstms with localized restrictions. Winds mostly from the west at around 5 kt, but light and variable at times especially overnight. Moderate confidence. && .MARINE... Winds and seas should stay below SCA criteria through tonight. Outlook... Wednesday-Saturday... No marine headlines are anticipated. Winds mostly between southeast and southwest with gusts of 20 kt or less. Seas 2 to 3 ft. Several opportunities for showers and tstms. Rip Currents... A low risk for the formation of dangerous rip currents is expected to continue through Wednesday. However, we are monitoring wave and swell trends as Tropical Storm Henri (currently south of Bermuda) is in a prime location to increase the risk for rip currents in our region. Henri should stay well away from our region, but it could send some long period swells towards our region. That being said, wave guidance does not depict any significant increase in the next several days. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...None. NJ...None. DE...None. MD...None. MARINE...None. && Synopsis...O'Brien Near Term...Davis/Johnson Short Term...O'Brien Long Term...O'Brien Aviation...Davis/Johnson/O'Brien Marine...Johnson/O'Brien
Hazardous Weather Outlook National Weather Service Mount Holly NJ 1057 AM EDT Tue Aug 17 2021 DEZ001-181457- New Castle- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for New Castle County in Delaware. .DAY ONE...Through tonight. There is a low probability of widespread hazardous weather. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. Minor coastal flooding is possible on Wednesday. Several instances of flooding are possible on Wednesday, especially in urban and poor-drainage areas and near particularly vulnerable small creeks and streams. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. DEZ002-181457- Kent- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for Kent County in Delaware. .DAY ONE...Through tonight. Minor coastal flooding is possible. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. Minor coastal flooding is possible on Wednesday. Minor coastal flooding is possible on Thursday. Minor coastal flooding is possible on Friday. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. DEZ003-181457- Inland Sussex- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for inland portions of Sussex County in Delaware. .DAY ONE...Through tonight. There is a low probability of widespread hazardous weather. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. Minor coastal flooding is possible on Friday. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. DEZ004-181457- Delaware Beaches- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for the Atlantic coastal portions of Sussex County in Delaware. .DAY ONE...Through tonight. There is a low probability of widespread hazardous weather. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. Minor coastal flooding is possible on Friday. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. PAZ054-181457- Carbon- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for Carbon County in Pennsylvania. .DAY ONE...Through tonight. Several instances of flooding are possible, especially in urban and poor-drainage areas and near vulnerable small creeks and streams. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. Several instances of flooding are possible on Wednesday, especially in urban and poor-drainage areas and near particularly vulnerable small creeks and streams. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. PAZ055-181457- Monroe- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for Monroe County in Pennsylvania. .DAY ONE...Through tonight. Several instances of flooding are possible, especially in urban and poor-drainage areas and near vulnerable small creeks and streams. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. Several instances of flooding are possible on Wednesday, especially in urban and poor-drainage areas and near particularly vulnerable small creeks and streams. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. PAZ060-181457- Berks- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for Berks County in Pennsylvania. .DAY ONE...Through tonight. Several instances of flooding are possible, especially in urban and poor-drainage areas and near vulnerable small creeks and streams. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. Several instances of flooding are possible on Wednesday, especially in urban and poor-drainage areas and near particularly vulnerable small creeks and streams. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. PAZ061-181457- Lehigh- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for Lehigh County in Pennsylvania. .DAY ONE...Through tonight. Several instances of flooding are possible, especially in urban and poor-drainage areas and near vulnerable small creeks and streams. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. Several instances of flooding are possible on Wednesday, especially in urban and poor-drainage areas and near particularly vulnerable small creeks and streams. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. PAZ062-181457- Northampton- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for Northampton County in Pennsylvania. .DAY ONE...Through tonight. Several instances of flooding are possible, especially in urban and poor-drainage areas and near vulnerable small creeks and streams. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. Several instances of flooding are possible on Wednesday, especially in urban and poor-drainage areas and near particularly vulnerable small creeks and streams. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. PAZ070-181457- Delaware- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for Delaware County in Pennsylvania. .DAY ONE...Through tonight. There is a low probability of widespread hazardous weather. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. Several instances of flooding are possible on Wednesday, especially in urban and poor-drainage areas and near particularly vulnerable small creeks and streams. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. PAZ071-181457- Philadelphia- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for Philadelphia County in Pennsylvania. .DAY ONE...Through tonight. There is a low probability of widespread hazardous weather. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. Several instances of flooding are possible on Wednesday, especially in urban and poor-drainage areas and near particularly vulnerable small creeks and streams. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. PAZ101-181457- Western Chester- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for western Chester County in Pennsylvania. .DAY ONE...Through tonight. Several instances of flooding are possible, especially in urban and poor-drainage areas and near vulnerable small creeks and streams. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. Several instances of flooding are possible on Wednesday, especially in urban and poor-drainage areas and near particularly vulnerable small creeks and streams. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. PAZ102-181457- Eastern Chester- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for eastern Chester County in Pennsylvania. .DAY ONE...Through tonight. Several instances of flooding are possible, especially in urban and poor-drainage areas and near vulnerable small creeks and streams. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. Several instances of flooding are possible on Wednesday, especially in urban and poor-drainage areas and near particularly vulnerable small creeks and streams. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. PAZ103-181457- Western Montgomery- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for western Montgomery County in Pennsylvania. .DAY ONE...Through tonight. Several instances of flooding are possible, especially in urban and poor-drainage areas and near vulnerable small creeks and streams. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. Several instances of flooding are possible on Wednesday, especially in urban and poor-drainage areas and near particularly vulnerable small creeks and streams. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. PAZ104-181457- Eastern Montgomery- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for eastern Montgomery County in Pennsylvania. .DAY ONE...Through tonight. There is a low probability of widespread hazardous weather. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. Several instances of flooding are possible on Wednesday, especially in urban and poor-drainage areas and near particularly vulnerable small creeks and streams. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. PAZ105-181457- Upper Bucks- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for upper Bucks County in Pennsylvania. .DAY ONE...Through tonight. Several instances of flooding are possible, especially in urban and poor-drainage areas and near vulnerable small creeks and streams. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. Several instances of flooding are possible on Wednesday, especially in urban and poor-drainage areas and near particularly vulnerable small creeks and streams. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. PAZ106-181457- Lower Bucks- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for lower Bucks County in Pennsylvania. .DAY ONE...Through tonight. There is a low probability of widespread hazardous weather. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. Several instances of flooding are possible on Wednesday, especially in urban and poor-drainage areas and near particularly vulnerable small creeks and streams. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. NJZ001-181457- Sussex- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for Sussex County in New Jersey. .DAY ONE...Through tonight. Several instances of flooding are possible, especially in urban and poor-drainage areas and near vulnerable small creeks and streams. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. Several instances of flooding are possible on Wednesday, especially in urban and poor-drainage areas and near particularly vulnerable small creeks and streams. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. NJZ007-181457- Warren- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for Warren County in New Jersey. .DAY ONE...Through tonight. Several instances of flooding are possible, especially in urban and poor-drainage areas and near vulnerable small creeks and streams. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. Several instances of flooding are possible on Wednesday, especially in urban and poor-drainage areas and near particularly vulnerable small creeks and streams. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. NJZ008-181457- Morris- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for Morris County in New Jersey. .DAY ONE...Through tonight. There is a low probability of widespread hazardous weather. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. Several instances of flooding are possible on Wednesday, especially in urban and poor-drainage areas and near particularly vulnerable small creeks and streams. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. NJZ009-181457- Hunterdon- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for Hunterdon County in New Jersey. .DAY ONE...Through tonight. There is a low probability of widespread hazardous weather. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. Several instances of flooding are possible on Wednesday, especially in urban and poor-drainage areas and near particularly vulnerable small creeks and streams. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. NJZ010-181457- Somerset- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for Somerset County in New Jersey. .DAY ONE...Through tonight. There is a low probability of widespread hazardous weather. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. Several instances of flooding are possible on Wednesday, especially in urban and poor-drainage areas and near particularly vulnerable small creeks and streams. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. NJZ012-181457- Middlesex- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for Middlesex County in New Jersey. .DAY ONE...Through tonight. The probability for widespread hazardous weather is low. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. The probability for widespread hazardous weather is low. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. NJZ013-181457- Western Monmouth- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for western Monmouth County in New Jersey. .DAY ONE...Through tonight. The probability for widespread hazardous weather is low. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. The probability for widespread hazardous weather is low. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. NJZ014-181457- Eastern Monmouth- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for eastern Monmouth County in New Jersey. .DAY ONE...Through tonight. The probability for widespread hazardous weather is low. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. The probability for widespread hazardous weather is low. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. NJZ015-181457- Mercer- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for Mercer County in New Jersey. .DAY ONE...Through tonight. There is a low probability of widespread hazardous weather. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. Several instances of flooding are possible on Wednesday, especially in urban and poor-drainage areas and near particularly vulnerable small creeks and streams. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. NJZ016-181457- Salem- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for Salem County in New Jersey. .DAY ONE...Through tonight. There is a low probability of widespread hazardous weather. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. Minor coastal flooding is possible on Wednesday. Several instances of flooding are possible on Wednesday, especially in urban and poor-drainage areas and near particularly vulnerable small creeks and streams. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. NJZ017-181457- Gloucester- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for Gloucester County in New Jersey. .DAY ONE...Through tonight. The probability for widespread hazardous weather is low. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. The probability for widespread hazardous weather is low. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. NJZ018-181457- Camden- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for Camden County in New Jersey. .DAY ONE...Through tonight. The probability for widespread hazardous weather is low. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. The probability for widespread hazardous weather is low. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. NJZ019-181457- Northwestern Burlington- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for northwestern Burlington County in New Jersey. .DAY ONE...Through tonight. The probability for widespread hazardous weather is low. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. The probability for widespread hazardous weather is low. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. NJZ020-181457- Ocean- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for inland portions of Ocean County in New Jersey. .DAY ONE...Through tonight. The probability for widespread hazardous weather is low. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. The probability for widespread hazardous weather is low. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. NJZ021-181457- Cumberland- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for Cumberland County in New Jersey. .DAY ONE...Through tonight. The probability for widespread hazardous weather is low. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. The probability for widespread hazardous weather is low. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. NJZ022-181457- Atlantic- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for inland portions of Atlantic County in New Jersey. .DAY ONE...Through tonight. The probability for widespread hazardous weather is low. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. The probability for widespread hazardous weather is low. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. NJZ023-181457- Cape May- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for Cape May County excluding the Atlantic coast in New Jersey. .DAY ONE...Through tonight. There is a low probability of widespread hazardous weather. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. Minor coastal flooding is possible on Thursday. Minor coastal flooding is possible on Friday. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. NJZ024-181457- Atlantic Coastal Cape May- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for the Atlantic coastal portions of Cape May County in New Jersey. .DAY ONE...Through tonight. There is a low probability of widespread hazardous weather. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. Minor coastal flooding is possible on Thursday. Minor coastal flooding is possible on Friday. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. NJZ025-181457- Coastal Atlantic- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for coastal portions of Atlantic County in New Jersey. .DAY ONE...Through tonight. The probability for widespread hazardous weather is low. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. The probability for widespread hazardous weather is low. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. NJZ026-181457- Coastal Ocean- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for coastal portions of Ocean County in New Jersey. .DAY ONE...Through tonight. The probability for widespread hazardous weather is low. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. The probability for widespread hazardous weather is low. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. NJZ027-181457- Southeastern Burlington- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for southeastern Burlington County in New Jersey. .DAY ONE...Through tonight. The probability for widespread hazardous weather is low. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. The probability for widespread hazardous weather is low. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. MDZ012-181457- Kent MD- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for Kent County in Maryland. .DAY ONE...Through tonight. There is a low probability of widespread hazardous weather. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. Several instances of flooding are possible on Wednesday, especially in urban and poor-drainage areas and near particularly vulnerable small creeks and streams. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. MDZ015-181457- Queen Annes- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for Queen Annes County in Maryland. .DAY ONE...Through tonight. There is a low probability of widespread hazardous weather. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. Several instances of flooding are possible on Wednesday, especially in urban and poor-drainage areas and near particularly vulnerable small creeks and streams. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. MDZ019-181457- Talbot- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for Talbot County in Maryland. .DAY ONE...Through tonight. The probability for widespread hazardous weather is low. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. The probability for widespread hazardous weather is low. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. MDZ020-181457- Caroline- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for Caroline County in Maryland. .DAY ONE...Through tonight. The probability for widespread hazardous weather is low. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. The probability for widespread hazardous weather is low. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. ANZ430-181457- Delaware Bay waters north of East Point NJ to Slaughter Beach DE- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for upper Delaware Bay. .DAY ONE...Through tonight. The probability for widespread hazardous weather is low. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. The probability for widespread hazardous weather is low. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. ANZ431-181457- Delaware Bay waters south of East Point NJ to Slaughter Beach DE- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for lower Delaware Bay. .DAY ONE...Through tonight. The probability for widespread hazardous weather is low. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. The probability for widespread hazardous weather is low. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. ANZ450-181457- Coastal waters from Sandy Hook to Manasquan Inlet NJ out 20 nm- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for the Atlantic coastal waters adjacent to Monmouth County out 20 nm. .DAY ONE...Through tonight. The probability for widespread hazardous weather is low. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. The probability for widespread hazardous weather is low. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. ANZ451-181457- Coastal waters from Manasquan Inlet to Little Egg Inlet NJ out 20 nm- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for the Atlantic coastal waters adjacent to Ocean County out 20 nm. .DAY ONE...Through tonight. The probability for widespread hazardous weather is low. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. The probability for widespread hazardous weather is low. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. ANZ452-181457- Coastal waters from Little Egg Inlet to Great Egg Inlet NJ out 20 nm- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for the Atlantic coastal waters adjacent to Atlantic County out 20 nm. .DAY ONE...Through tonight. The probability for widespread hazardous weather is low. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. The probability for widespread hazardous weather is low. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. ANZ453-181457- Coastal waters from Great Egg Inlet to Cape May NJ out 20 nm- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for the Atlantic coastal waters adjacent to Cape May County out 20 nm. .DAY ONE...Through tonight. The probability for widespread hazardous weather is low. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. The probability for widespread hazardous weather is low. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. ANZ454-181457- Coastal waters from Cape May NJ to Cape Henlopen DE out 20 nm- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for the Atlantic coastal waters adjacent to the mouth of Delaware Bay out 20 nm. .DAY ONE...Through tonight. The probability for widespread hazardous weather is low. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. The probability for widespread hazardous weather is low. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. ANZ455-181457- Coastal waters from Cape Henlopen to Fenwick Island DE out 20 nm- 1057 AM EDT Tue Aug 17 2021 This Hazardous Weather Outlook is for the Atlantic coastal waters adjacent to Sussex County out 20 nm. .DAY ONE...Through tonight. The probability for widespread hazardous weather is low. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. The probability for widespread hazardous weather is low. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures.
The Dover AFB radar (KDOX), 98 km away, was scanning. The volume nearest the first event began at 18:13 UTC.
3 flash flood. Local standard time, as filed.
Old Ogletown Road near Ogletown was closed due to flooding.
US Route 40 in Glasgow was inundated with flood waters near DE Route 72.
Minor flooding occurred along the Christina River at Cooch's Bridge.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Delaware in 2021Every state in 2021This day in weather historyWarnings in Delaware, August 2021
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: 966823, 966824, 966825.