Thunderstorms developed near and north of the Baltimore, MD area in an environment of moderate instability and wind shear ahead of a cold front late on April 29. Cloud cover and showers from earlier in the day limited instability for most of the day, but some late day heating allowed sufficient destabilization for a few cells to develop.
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.
Thunderstorms developed near and north of the Baltimore, MD area in an environment of moderate instability and wind shear ahead of a cold front late on April 29. Cloud cover and showers from earlier in the day limited instability for most of the day, but some late day heating allowed sufficient destabilization for a few cells to develop. Storms organized into a line segment and tracked east-northeast into southeast Pennsylvania and south-central New Jersey. The storms became severe for a time, including while passing in and around the Philadelphia metro area, before gradually weakening as they tracked into lesser instability further east. A few reports of damaging wind were received.
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 Apr 29, 6:33 PM EST, 7 minutes earlier.
Area Forecast Discussion
National Weather Service Mount Holly NJ
733 PM EDT Thu Apr 29 2021
.SYNOPSIS...
A cold front will move through the region late tonight as low
pressure passes to our north. A strong secondary front will then
move through on Friday. High pressure will then build in for most of
the weekend before shifting offshore later Sunday. Another slow
moving frontal boundary and multiple waves of low pressure will
likely affect the region next week.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
A warm and humid airmass resides over the area today with
temperatures in the upper 70s to lower 80s and dewpoints in 60s. An
area of low pressure is currently centered just NW of the area,
riding along a nearly stalled frontal boundary. The low/baroclinic
zone will begin to shift eastward this afternoon as the eastern
North America northern-branch trough amplifies and pivots eastward.
Modest height falls are occurring over the area at present in
advance of a fairly potent shortwave rotating through the base of
the longwave trough. This fairly modest forcing is sparking some
light stratiform rain currently over western portions of the area
which will continue at times through the early afternoon. As we head
further into the afternoon there will be the chance for scattered
thunderstorm development as the shortwave approaches, with perhaps
mesoscale differential heating boundaries (reinforced somewhat by
the aforementioned stratiform precipitation shield) also serving to
initiate some storms. As mentioned earlier the convective parameter
space is a mixed-bag with fairly steep low-lvl lapse rates and
strong low-lvl wind fields partially offset by meager mid-lvl lapse
rates/skinny CAPE profiles. Feel SPC's marginal risk covers this
threat pretty accurately, with the main conditional storm threat
being strong-severe winds. Given PWATs in excess of 1.6 inches and
warm cloud layers approaching 10k ft, heavy rainfall will also be a
concern, although quick storm motion and the antecedent dry
conditions should preclude a greater hydro threat.
Overnight the aforementioned wave and cold front will pass through
the area, likely resulting in another round of precipitation. A bit
torn on whether to include thunder chances for the overnight period
given that a bit of residual MUCAPE persists through the frontal
passage, but for now will leave it out past midnight. The cold front
will cross through the area in the pre-dawn hours on Friday and we
should dry out fairly quickly behind it. Winds could become breezy
for a time behind the front late tonight but the stronger winds look
to hold off until Friday.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SATURDAY/...
...High Winds Expected Midday Friday through Friday Night...
A strong weather system remains on track to affect the region on
Friday. We are expecting very windy conditions from early Friday
afternoon through much of Friday night. Gusts over 45 mph are
likely, and gusts to near 60 mph are possible. Scattered instances
of downed trees and power outages are also expected, especially
given many trees are now bearing leaves. This will likely be an
impactful event.
Very little change in the forecast philosophy this cycle. A cold
front will be offshore by Friday morning. A strong shortwave trough
and associated vort max will rotate through the region during the
afternoon hours, which will also send a reinforcing cold front
through. This is a dynamically impressive system, with very strong
height falls expected in the local area tomorrow afternoon and
evening. The approaching shortwave and good jet dynamics will also
yield rapid intensification of low pressure departing into the
Canadian maritimes, with its pressure dropping near to below 980 mb.
At the same time, high pressure will be moving into the Great Lakes,
which combined with the deepening low to the northeast will create a
very strong pressure gradient, maximized over the mid-Atlantic.
Breezy conditions will already be underway Friday morning in the
wake of the first front, with gusts during the morning in the 30 to
35 mph range. A surge in winds is expected with the secondary cold
front. Along and just ahead of the front, a rain shower or squall is
possible, any of which may contain enhanced winds over 50 mph if
they form. But the coverage of precipitation should be minimal due
to decreasing moisture, with only a 10 to 20 percent chance of a
shower. Behind the front, low level wind fields strengthen
significantly in the late afternoon and evening. The model guidance
today looks quite similar to how it did last night and yesterday
afternoon. There is some spread in the exact magnitude of the winds
aloft, but 850mb winds are likely to exceed 50 kt and probably be
near 60 kt during the peak of the event in the evening. Still not
really concerned about boundary layer stabilization in the evening
hours with steep lapse through the low levels and impressive
tropopause folding around 500 mb, quite extreme especially for the
season. Profiles in BUFKIT are not indicating any degree of low
level inversion over most of the area. By later in the night, we
could see some stabilization, and winds aloft also decrease, so
gusts should gradually decrease later in the night.
We have upgraded the High Wind Watch to a High Wind Warning.
Confidence is only moderate at best that most areas will see gusts
of 60 mph, which is the technical warning threshold (some areas,
like the Poconos, have higher confidence). But with better
confidence in several hours of wind gusts near to above 50 mph, the
impacts will probably be more warning level. All portions of the CWA
should be prepared for wind gusts in excess of 50 mph and the
possibility of power outages.
The strong northwest winds will yield strong cold advection through
the night, driving temperatures down into the 40s, and 30s in the
far north. However, we are forecasting lows several degrees warmer
than model consensus due to the strong mixing that is expected,
which models frequently fail to capture.
By Saturday, a rapid trend towards more tranquil weather is
expected. The pressure gradient weakens significantly as the center
of high pressure moves closer. Wind gusts over 30 mph towards
daybreak should drop towards 20 mph for most of the day. We'll be
coming off a cool and blustery overnight, but we start to see some
warm advection by late in the day as winds turn more westerly.
Abundant sunshine is also expected. This should boost high
temperatures into the mid 60s in most areas, which is only slightly
below average. Overall, it will be a nice day.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
The medium-range period looks fairly active, with multiple
perturbations moving through fairly fast upper-level flow with a
slowly sagging front moving through the Northeast and Mid-Atlantic
during the early to middle portion of the week.
At the start of the period (00z Sunday), a potent vort max will be
digging southeastward through eastern Canada with northwest midlevel
flow encompassing the northern tier of the U.S. There should be
precipitation in advance of the shortwave trough extending into
portions of New England and New York. However, questions remain
regarding how far south the precipitation will extend, given the
stronger lift should remain well north of the area. It does appear,
though, that showers will be present at least into portions of the
Poconos and northwest New Jersey Saturday night. Have included some
PoPs for this period. Precipitation amounts should be light.
The attendant front will stall as it impinges upon the large-scale
ridging farther south. This stalling will likely occur in the
northern Mid-Atlantic, so cannot rule out some showers lingering in
the northern CWA through the day Sunday. To the south, meanwhile,
considerable warming will occur as heights rise to the
south/southwest of the passing shortwave trough. Highs will likely
reach the 80s in central/southern portions of the CWA, and I do
wonder if guidance is too low in the far southern CWA (safely away
from the front, and likely experiencing more considerable
insolation).
A southern-stream vort max will lift northeastward quickly from the
Deep South to the upper Ohio Valley by Monday afternoon. Transient
downstream ridging will amplify as this unfolds, likely keeping most
of the Sunday night/Monday morning period dry for our area. However,
convection is anticipated downstream of the perturbation during the
day, likely encompassing much of the lower Midwest east to the
Appalachians. Pattern-wise, strong to severe convection seems
probable in portions of these regions, and if the convection holds
together as it moves east to the Mid-Atlantic by evening, may have
some of our own. Will need to watch this, especially if the timing
of the perturbation is faster (more favorable diurnal timing).
Increased PoPs considerably for this period, as model agreement
seems to have improved for this portion of the forecast.
The perturbation will continue to shear apart as it runs into
confluent flow from the amplified ridging. Thus, the front will make
little progress southward during this period. Another perturbation
will likely approach the region Tuesday and Wednesday. Timing is
very uncertain (GFS almost 12-18 hours faster than the ECMWF), and
will be critical for chances of severe storms. Nevertheless,
expecting another round of precipitation some time between Tuesday
afternoon and Wednesday night. Notably, the track of the associated
low will be important too, as a swath of more stratiform
precipitation on the cold side of the baroclinic zone should be
expected as well. For example, the 12z ECMWF indicates a period of
warm-advection precipitation Tuesday night for the northern half of
the forecast area, followed by stronger convection on Wednesday in
the central/southern portions of the area as the low moves through
the region.
Another perturbation may move through the eastern U.S. on Thursday,
but the front may finally make enough progress southward by this
point for impacts to be mostly south of our area. However,
deterministic models are hinting at a developing wave along the
front lifting northeastward and bringing the East Coast another dose
of (potentially healthy) precipitation as deep cyclogenesis occurs.
Plenty of time to figure that out, though.
&&
.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY and surrounding areas.
Overnight...A line of showers with embedded thunder, including
brief IFR conditions, will affect several of the terminals
including PHL through 02z. Once that line moves through, mainly
VFR with an additional round of lighter showers between 03z and
08z. Brief periods of MVFR may occur for a time during and
after precipitation occurs. Winds shifting from southwest to
west then west-northwest at around 10 to 15 kt with gusts to 25
kt. Moderate confidence.
Friday...VFR with SCT-BKN CIGs around 5000 feet. Very strong
west to northwest winds 20 to 30 kt with gusts to 40+ kt
possible by afternoon. High confidence.
Friday night...VFR with west to northwest winds 20 to 30 kt and
gusts to 40+ kt through 06z, diminishing to 10 to 20 kt with
gusts to 25 kt by late in the night. Moderate confidence.
Outlook...
Saturday...VFR with northwest winds 10 to 20 kt with gusts to 25
kt or so. High confidence.
Saturday night and Sunday...VFR with winds becoming west or
southwest around 10 kt with occasional gusts to 20 kt on Sunday.
Moderate confidence.
Sunday night and Monday...Mainly VFR with southwest winds 5 to
15 kt (lighter at night). A chance of showers late in the day. Moderate
confidence.
Monday night and Tuesday...At least brief restrictions possible
with a chance of showers (and possibly storms on Tuesday). West
to southwest winds 5 to 15 kt. Low confidence.
&&
.MARINE...
Winds will likely increase to 25-30kts overnight into Friday morning
so an SCA remains up for all waters for that period. A gradual shift
from southwest to west is expected. Seas will increase to 5-6ft this
evening as well on the ocean waters. Isolated thunderstorms will be
possible through this evening with sporadic gusty winds possible.
Winds will increase further on Friday, and shift to northwest, as a
pair of fronts move through. For most of the daytime on Friday, wind
gusts of 35 to 45 kt are expected, though they could be a bit less
in the morning. Given these expectations, a Gale Warning is now in
effect for the daytime period on Friday. The strongest winds are
expected from very late Friday afternoon through the first half of
Friday night, when gusts to near 50 kt are possible. For that
reason, a Storm Watch remains in effect following the Gale Warning.
Pending better confidence in the forecast, we will either upgrade
the Storm Watch to a Storm Warning, or will extend the Gale Warning
through Friday night.
By Saturday, a rapid improving trend is expected. Winds will drop to
SCA levels in the morning, and winds and seas will both drop to sub-
SCA levels in the afternoon. Winds will shift more to west with
time.
Outlook...
Saturday night through Tuesday...Mainly sub-advisory conditions
expected, although conditions may be close Monday night and Tuesday.
There will also be a chance of storms Monday night and Tuesday.
&&
.FIRE WEATHER...
Windy and dry conditions are expected to develop Friday afternoon
through Saturday across the area. Depending on the total amount of
precip that falls across the area through early Friday, favorable
fire-weather conditions may develop during the Friday afternoon
through Saturday period. Northwesterly winds are forecast to gust to
40-50+ mph Friday night with maximum relative humidity values mostly
in the 40s. Minimum relative humidity will likely fall into the 20s
on Saturday with winds continuing to gust to around 20-25 mph. We
have contacted state fire weather partners from across the area, who
confirm most of the region will be sufficiently wet and/or greened-
up to avoid any concerns. However, a Special Weather Statement may
be needed for the Pine Barrens region of New Jersey, where the green-
up is slower. We will monitor trends in observed rainfall.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...High Wind Warning from 2 PM Friday to 4 AM EDT Saturday for
PAZ054-055-060>062-070-071-101>106.
NJ...High Wind Warning from 2 PM Friday to 4 AM EDT Saturday for
NJZ001-007>010-012>027.
DE...High Wind Warning from 2 PM Friday to 4 AM EDT Saturday for
DEZ001>004.
MD...High Wind Warning from 2 PM Friday to 4 AM EDT Saturday for
MDZ012-015-019-020.
MARINE...Storm Watch from Friday evening through late Friday night for
ANZ430-431-450>455.
Small Craft Advisory until 6 AM EDT Friday for ANZ450>455.
Gale Warning from 6 AM to 6 PM EDT Friday for ANZ430-431-
450>455.
Small Craft Advisory until 6 AM EDT Friday for ANZ430-431.
&&
Synopsis...O'Brien
Near Term...Carr
Short Term...O'Brien
Long Term...CMS
Aviation...CMS
Marine...CMS/Carr/O'Brien
Fire Weather...WFO PHIHazardous Weather Outlook National Weather Service Mount Holly NJ 0737 PM EDT Thu Apr 29 2021 DEZ001-302337- New Castle- 0737 PM EDT Thu Apr 29 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...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. High Wind Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. DEZ002-302337- Kent- 0737 PM EDT Thu Apr 29 2021 This Hazardous Weather Outlook is for Kent County in Delaware. .DAY ONE...Through tonight. There is a low probability of widespread hazardous weather. .DAYS TWO THROUGH SEVEN...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. High Wind Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. DEZ003-302337- Inland Sussex- 0737 PM EDT Thu Apr 29 2021 This Hazardous Weather Outlook is for inland portions of Sussex County in Delaware. .DAY ONE...Through tonight. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .DAYS TWO THROUGH SEVEN...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. High Wind Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. DEZ004-302337- Delaware Beaches- 0737 PM EDT Thu Apr 29 2021 This Hazardous Weather Outlook is for the Atlantic coastal portions of Sussex County in Delaware. .DAY ONE...Through tonight. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .DAYS TWO THROUGH SEVEN...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. High Wind Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. PAZ054-302337- Carbon- 0737 PM EDT Thu Apr 29 2021 This Hazardous Weather Outlook is for Carbon County in Pennsylvania. .DAY ONE...Through tonight. There is a low probability of widespread hazardous weather. .DAYS TWO THROUGH SEVEN...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. High Wind Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. PAZ055-302337- Monroe- 0737 PM EDT Thu Apr 29 2021 This Hazardous Weather Outlook is for Monroe County in Pennsylvania. .DAY ONE...Through tonight. There is a low probability of widespread hazardous weather. .DAYS TWO THROUGH SEVEN...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. High Wind Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. PAZ060-302337- Berks- 0737 PM EDT Thu Apr 29 2021 This Hazardous Weather Outlook is for Berks County in Pennsylvania. .DAY ONE...Through tonight. There is a low probability of widespread hazardous weather. .DAYS TWO THROUGH SEVEN...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. High Wind Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. PAZ061-302337- Lehigh- 0737 PM EDT Thu Apr 29 2021 This Hazardous Weather Outlook is for Lehigh County in Pennsylvania. .DAY ONE...Through tonight. There is a low probability of widespread hazardous weather. .DAYS TWO THROUGH SEVEN...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. High Wind Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. PAZ062-302337- Northampton- 0737 PM EDT Thu Apr 29 2021 This Hazardous Weather Outlook is for Northampton County in Pennsylvania. .DAY ONE...Through tonight. There is a low probability of widespread hazardous weather. .DAYS TWO THROUGH SEVEN...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. High Wind Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. PAZ070-302337- Delaware- 0737 PM EDT Thu Apr 29 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...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. High Wind Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. PAZ071-302337- Philadelphia- 0737 PM EDT Thu Apr 29 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...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. High Wind Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. PAZ101-302337- Western Chester- 0737 PM EDT Thu Apr 29 2021 This Hazardous Weather Outlook is for western Chester County in Pennsylvania. .DAY ONE...Through tonight. There is a low probability of widespread hazardous weather. .DAYS TWO THROUGH SEVEN...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. High Wind Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. PAZ102-302337- Eastern Chester- 0737 PM EDT Thu Apr 29 2021 This Hazardous Weather Outlook is for eastern Chester County in Pennsylvania. .DAY ONE...Through tonight. There is a low probability of widespread hazardous weather. .DAYS TWO THROUGH SEVEN...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. High Wind Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. PAZ103-302337- Western Montgomery- 0737 PM EDT Thu Apr 29 2021 This Hazardous Weather Outlook is for western Montgomery County in Pennsylvania. .DAY ONE...Through tonight. There is a low probability of widespread hazardous weather. .DAYS TWO THROUGH SEVEN...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. High Wind Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. PAZ104-302337- Eastern Montgomery- 0737 PM EDT Thu Apr 29 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...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. High Wind Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. PAZ105-302337- Upper Bucks- 0737 PM EDT Thu Apr 29 2021 This Hazardous Weather Outlook is for upper Bucks County in Pennsylvania. .DAY ONE...Through tonight. There is a low probability of widespread hazardous weather. .DAYS TWO THROUGH SEVEN...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. High Wind Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. PAZ106-302337- Lower Bucks- 0737 PM EDT Thu Apr 29 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...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. High Wind Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. NJZ001-302337- Sussex- 0737 PM EDT Thu Apr 29 2021 This Hazardous Weather Outlook is for Sussex County in New Jersey. .DAY ONE...Through tonight. There is a low probability of widespread hazardous weather. .DAYS TWO THROUGH SEVEN...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. High Wind Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. NJZ007-302337- Warren- 0737 PM EDT Thu Apr 29 2021 This Hazardous Weather Outlook is for Warren County in New Jersey. .DAY ONE...Through tonight. There is a low probability of widespread hazardous weather. .DAYS TWO THROUGH SEVEN...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. High Wind Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. NJZ008-302337- Morris- 0737 PM EDT Thu Apr 29 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...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. High Wind Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. NJZ009-302337- Hunterdon- 0737 PM EDT Thu Apr 29 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...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. High Wind Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. NJZ010-302337- Somerset- 0737 PM EDT Thu Apr 29 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...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. High Wind Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. NJZ012-302337- Middlesex- 0737 PM EDT Thu Apr 29 2021 This Hazardous Weather Outlook is for Middlesex County in New Jersey. .DAY ONE...Through tonight. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .DAYS TWO THROUGH SEVEN...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. High Wind Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. NJZ013-302337- Western Monmouth- 0737 PM EDT Thu Apr 29 2021 This Hazardous Weather Outlook is for western Monmouth County in New Jersey. .DAY ONE...Through tonight. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .DAYS TWO THROUGH SEVEN...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. High Wind Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. NJZ014-302337- Eastern Monmouth- 0737 PM EDT Thu Apr 29 2021 This Hazardous Weather Outlook is for eastern Monmouth County in New Jersey. .DAY ONE...Through tonight. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .DAYS TWO THROUGH SEVEN...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. High Wind Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. NJZ015-302337- Mercer- 0737 PM EDT Thu Apr 29 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...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. High Wind Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. NJZ016-302337- Salem- 0737 PM EDT Thu Apr 29 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...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. High Wind Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. NJZ017-302337- Gloucester- 0737 PM EDT Thu Apr 29 2021 This Hazardous Weather Outlook is for Gloucester County in New Jersey. .DAY ONE...Through tonight. There is a low probability of widespread hazardous weather. .DAYS TWO THROUGH SEVEN...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. High Wind Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. NJZ018-302337- Camden- 0737 PM EDT Thu Apr 29 2021 This Hazardous Weather Outlook is for Camden County in New Jersey. .DAY ONE...Through tonight. There is a low probability of widespread hazardous weather. .DAYS TWO THROUGH SEVEN...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. High Wind Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. NJZ019-302337- Northwestern Burlington- 0737 PM EDT Thu Apr 29 2021 This Hazardous Weather Outlook is for northwestern Burlington County in New Jersey. .DAY ONE...Through tonight. There is a low probability of widespread hazardous weather. .DAYS TWO THROUGH SEVEN...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. High Wind Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. NJZ020-302337- Ocean- 0737 PM EDT Thu Apr 29 2021 This Hazardous Weather Outlook is for inland portions of Ocean County in New Jersey. .DAY ONE...Through tonight. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .DAYS TWO THROUGH SEVEN...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. High Wind Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. NJZ021-302337- Cumberland- 0737 PM EDT Thu Apr 29 2021 This Hazardous Weather Outlook is for Cumberland County in New Jersey. .DAY ONE...Through tonight. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .DAYS TWO THROUGH SEVEN...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. High Wind Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. NJZ022-302337- Atlantic- 0737 PM EDT Thu Apr 29 2021 This Hazardous Weather Outlook is for inland portions of Atlantic County in New Jersey. .DAY ONE...Through tonight. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .DAYS TWO THROUGH SEVEN...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. High Wind Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. NJZ023-302337- Cape May- 0737 PM EDT Thu Apr 29 2021 This Hazardous Weather Outlook is for Cape May County excluding the Atlantic coast in New Jersey. .DAY ONE...Through tonight. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .DAYS TWO THROUGH SEVEN...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. High Wind Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. NJZ024-302337- Atlantic Coastal Cape May- 0737 PM EDT Thu Apr 29 2021 This Hazardous Weather Outlook is for the Atlantic coastal portions of Cape May County in New Jersey. .DAY ONE...Through tonight. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .DAYS TWO THROUGH SEVEN...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. High Wind Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. NJZ025-302337- Coastal Atlantic- 0737 PM EDT Thu Apr 29 2021 This Hazardous Weather Outlook is for coastal portions of Atlantic County in New Jersey. .DAY ONE...Through tonight. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .DAYS TWO THROUGH SEVEN...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. High Wind Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. NJZ026-302337- Coastal Ocean- 0737 PM EDT Thu Apr 29 2021 This Hazardous Weather Outlook is for coastal portions of Ocean County in New Jersey. .DAY ONE...Through tonight. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .DAYS TWO THROUGH SEVEN...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. High Wind Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. NJZ027-302337- Southeastern Burlington- 0737 PM EDT Thu Apr 29 2021 This Hazardous Weather Outlook is for southeastern Burlington County in New Jersey. .DAY ONE...Through tonight. Please go to weather.gov/phi/ehwo for more information on potential weather hazards. .DAYS TWO THROUGH SEVEN...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. High Wind Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. MDZ012-302337- Kent MD- 0737 PM EDT Thu Apr 29 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...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. High Wind Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. MDZ015-302337- Queen Annes- 0737 PM EDT Thu Apr 29 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...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. High Wind Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. MDZ019-302337- Talbot- 0737 PM EDT Thu Apr 29 2021 This Hazardous Weather Outlook is for Talbot County in Maryland. .DAY ONE...Through tonight. There is a low probability of widespread hazardous weather. .DAYS TWO THROUGH SEVEN...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. High Wind Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. MDZ020-302337- Caroline- 0737 PM EDT Thu Apr 29 2021 This Hazardous Weather Outlook is for Caroline County in Maryland. .DAY ONE...Through tonight. There is a low probability of widespread hazardous weather. .DAYS TWO THROUGH SEVEN...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. High Wind Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. ANZ430-302337- Delaware Bay waters north of East Point NJ to Slaughter Beach DE- 0737 PM EDT Thu Apr 29 2021 This Hazardous Weather Outlook is for upper Delaware Bay. .DAY ONE...Through tonight. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. Gale Warning. .DAYS TWO THROUGH SEVEN...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. Storm Watch. Gale Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. ANZ431-302337- Delaware Bay waters south of East Point NJ to Slaughter Beach DE- 0737 PM EDT Thu Apr 29 2021 This Hazardous Weather Outlook is for lower Delaware Bay. .DAY ONE...Through tonight. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. Gale Warning. .DAYS TWO THROUGH SEVEN...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. Storm Watch. Gale Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. ANZ450-302337- Coastal waters from Sandy Hook to Manasquan Inlet NJ out 20 nm- 0737 PM EDT Thu Apr 29 2021 This Hazardous Weather Outlook is for the Atlantic coastal waters adjacent to Monmouth County out 20 nm. .DAY ONE...Through tonight. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. Gale Warning. .DAYS TWO THROUGH SEVEN...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. Storm Watch. Gale Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. ANZ451-302337- Coastal waters from Manasquan Inlet to Little Egg Inlet NJ out 20 nm- 0737 PM EDT Thu Apr 29 2021 This Hazardous Weather Outlook is for the Atlantic coastal waters adjacent to Ocean County out 20 nm. .DAY ONE...Through tonight. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. Gale Warning. .DAYS TWO THROUGH SEVEN...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. Storm Watch. Gale Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. ANZ452-302337- Coastal waters from Little Egg Inlet to Great Egg Inlet NJ out 20 nm- 0737 PM EDT Thu Apr 29 2021 This Hazardous Weather Outlook is for the Atlantic coastal waters adjacent to Atlantic County out 20 nm. .DAY ONE...Through tonight. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. Gale Warning. .DAYS TWO THROUGH SEVEN...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. Storm Watch. Gale Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. ANZ453-302337- Coastal waters from Great Egg Inlet to Cape May NJ out 20 nm- 0737 PM EDT Thu Apr 29 2021 This Hazardous Weather Outlook is for the Atlantic coastal waters adjacent to Cape May County out 20 nm. .DAY ONE...Through tonight. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. Gale Warning. .DAYS TWO THROUGH SEVEN...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. Storm Watch. Gale Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. ANZ454-302337- Coastal waters from Cape May NJ to Cape Henlopen DE out 20 nm- 0737 PM EDT Thu Apr 29 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. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. Gale Warning. .DAYS TWO THROUGH SEVEN...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. Storm Watch. Gale Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. ANZ455-302337- Coastal waters from Cape Henlopen to Fenwick Island DE out 20 nm- 0737 PM EDT Thu Apr 29 2021 This Hazardous Weather Outlook is for the Atlantic coastal waters adjacent to Sussex County out 20 nm. .DAY ONE...Through tonight. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. Gale Warning. .DAYS TWO THROUGH SEVEN...Friday through Wednesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. Storm Watch. Gale Warning. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures.
The Philadelphia radar (KDIX), 91 km away, was scanning. The volume nearest the first event began at 23:40 UTC.
4 thunderstorm wind. Local standard time, as filed.
Trees and wires were downed near Summit Ln in Chester Heights. Time estimated from radar.
Trees and wires were downed near Valley Rd in Woodlyn. Time estimated from radar.
Wires were downed near Hook Rd in Darby Twp. Time estimated from radar.
An mPing report of snapped or uprooted trees at this location, matching an area of high velocities on radar. Time estimated from radar.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Pennsylvania in 2021Every state in 2021This day in weather historyWarnings in Pennsylvania, April 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: 947470, 947471, 947472, 947473.