Alert archive / Pennsylvania / Areal Flood Warnings in 2018

Areal Flood Warning 125, NWS Philadelphia/Mount Holly

December 21, 20185 counties in Pennsylvania; New Castle County, Delaware; Cecil County, Maryland

NWS Philadelphia/Mount Holly issued this areal flood warning at Dec 21, 2018, 8:04 AM EST for 5 counties in Pennsylvania; New Castle County, Delaware; Cecil County, Maryland. It was in force for 7 hr. 10 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Dec 21, 2018, 8:04 AM EST (13:04 UTC)
Expired
Dec 21, 2018, 2:50 PM EST
In force
7 hr
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Flood severity
None

Counties New Castle County, DE, Cecil County, MD, Berks County, PA, Chester County, PA, Delaware County, PA, Montgomery County, PA, Philadelphia County, PA

The radar

The Philadelphia radar (KDIX), 119 km from the middle of the area, began a volume at 13:03 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

What was reported inside it

TimeReportWhereRemark
Dec 21, 8:23 AM ESTFLOOD1 Wsw Tioga, PAKELLY DR. BETWEEN FOUNTAIN GREEN DR. AND STRAWBERRY MANSION DR. CLOSED DUE TO FLOODING.
Dec 21, 8:45 AM ESTFLOOD1 Se Manayunk, PAWISSAHICKON CREEK EXCEEDED MINOR FLOOD STAGE OF 5 FEET.
Dec 21, 9:30 AM ESTFLOODChadds Ford Twp, PABRANDYWINE CREEK AT CHADDS FORD EXCEEDED MINOR FLOOD STAGE OF 9 FEET.
Dec 21, 9:30 AM ESTHEAVY RAIN 1.63Exton, PA
Dec 21, 10:13 AM ESTFLOOD1 Sw Hayden Park, DECOMBINATION OF FRESHWATER AND TIDAL FLOODING HAS CLOSED AIRPORT ROAD BETWEEN INTERSTATE 95 AND MCARTHUR DRIVE.
Dec 21, 10:16 AM ESTFLOOD1 Sse Wilmington, DECOMBINATION OF FRESHWATER AND TIDAL FLOODING IS INUNDATING PORTIONS OF ROUTE 13 AT THE WALNUT STREET BRIDGE. LANE RESTRICTIONS IN PLACE.
Dec 21, 10:40 AM ESTCOASTAL FLOOD1 Ssw Washington Park, DERIVER ROAD CLOSED BETWEEN CARROLL DRIVE AND CLYMER STREET OWING TO TIDAL FLOODING.
Dec 21, 10:48 AM ESTFLOOD1 Ese Monterey Farms, DERIVER ROAD CLOSED DUE TO FLOODING BETWEEN RTE 72 AND GRANTHAM LN.
Dec 21, 11:15 AM ESTFLOOD2 Ese Roxborough, PAKELLY DRIVE EASTBOUND CLOSED BETWEEN STRAWBERRY MANSION DRIVE AND FOUNTAIN GREEN DRIVE DUE TO FLOODING. REPORT VIA SOCIAL MEDIA.
Dec 21, 11:34 AM ESTFLOOD1 Se Roxborough, PAFLOODING ON MARTIN LUTHER KING JR. DRIVE BETWEEN MONTGOMERY DRIVE AND FALLS BRIDGE. ROAD CLOSED.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 1.1 hours before the alert went out and 172 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Washington/Dulle, VA at 12:00Z on 2018-12-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 91 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Washington/Dulle, VA at 12:00Z on 2018-12-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 224 square meters per square second.1939587897117136Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
91 J/kg
Mixed-layer CIN
-3 J/kg
Mixed-layer LCL
533 m above ground
0-6 km bulk shear
93 kt
0-1 km storm-relative helicity
224 m²/s²
0-3 km storm-relative helicity
139 m²/s²
Significant tornado parameter
0.1
Supercell composite
1.0

Open this sounding in Storm Lab

The text

As transmitted.

074 
WGUS41 KPHI 211304
FLWPHI

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Flood Warning
National Weather Service Mount Holly NJ
804 AM EST FRI DEC 21 2018

DEC003-MDC015-PAC011-029-045-091-101-211700-
/O.NEW.KPHI.FA.W.0125.181221T1304Z-181221T1700Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
New Castle DE-Cecil MD-Berks PA-Montgomery PA-Chester PA-
Philadelphia PA-Delaware PA-
804 AM EST FRI DEC 21 2018

The National Weather Service in Mount Holly NJ has issued a

* Flood Warning for...
  New Castle County in northern Delaware...
  Cecil County in northeastern Maryland...
  Southeastern Berks County in eastern Pennsylvania...
  Montgomery County in southeastern Pennsylvania...
  Chester County in southeastern Pennsylvania...
  Western Philadelphia County in southeastern Pennsylvania...
  Delaware County in southeastern Pennsylvania...

* Until noon EST.

* At 801 AM EST, Doppler radar and automated rain gauges indicated 
  that moderate to heavy rain was falling across the area. The heavy 
  rain will cause flooding. Up to two inches of rain have already 
  fallen. A number of creeks, streams, and rivers are flooding. 
  Perkiomen Creek at East Greenville is above flood stage. French 
  Creek at Phoenixville is above flood stage. Crum Creek at Newtown 
  Square is above flood stage. The East Branch Brandywine Creek is 
  above flood stage at Downingtown.

* Some locations that could experience flooding include...
  Philadelphia, Wilmington, Newark, West Chester, Elkton, Havre De
  Grace, Calvert, Norristown, Chester, Pottstown, Phoenixville,
  Lansdale, West Norriton, East Norriton, Pennsville, Coatesville,
  Yeadon, Westtown, Carneys Point and Downingtown.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around...don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.

A Flood Warning means that flooding is imminent or occurring. All
interested parties should take necessary precautions immediately.

&&

LAT...LON 3971 7623 3973 7610 3976 7606 3983 7604
      3987 7599 3995 7600 4004 7593 4011 7594
      4014 7588 4016 7590 4020 7586 4047 7558
      4016 7504 3986 7522 3984 7536 3977 7546
      3967 7551 3952 7564 3945 7577 3956 7609

$$

Kruzdlo
2 follow-up statements
647 
WGUS41 KPHI 211632
FLWPHI

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Flood Warning
National Weather Service Mount Holly NJ
1132 AM EST FRI DEC 21 2018

DEC003-MDC015-PAC011-029-045-091-101-212100-
/O.EXT.KPHI.FA.W.0125.000000T0000Z-181221T2100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
New Castle DE-Cecil MD-Berks PA-Montgomery PA-Chester PA-
Philadelphia PA-Delaware PA-
1132 AM EST FRI DEC 21 2018

The National Weather Service in Mount Holly NJ has extended the

* Flood Warning for...
  New Castle County in northern Delaware...
  Cecil County in northeastern Maryland...
  Southeastern Berks County in eastern Pennsylvania...
  Montgomery County in southeastern Pennsylvania...
  Chester County in southeastern Pennsylvania...
  Western Philadelphia County in southeastern Pennsylvania...
  Delaware County in southeastern Pennsylvania...

* Until 400 PM EST.

* At 1126 AM EST, Doppler radar indicated the moderate to heavy rain 
  was moving out of the region. Although the rain was moving out, it 
  will take time for it to drain. Many creeks and streams in 
  Northern Delaware remain high. The Brandywine Creek is running 
  high and is flooding across portions of Chester county. Creeks and 
  streams are running high in Delaware county including Ridley 
  Creek. The Wissahickon Creek is running high in both Philadelphia 
  and Montgomery counties. The West Branch of the Perkiomen Creek is 
  running high and is above flood stage in Upper Montgomery county. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around...don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.

A Flood Warning means that flooding is imminent or occurring. All
interested parties should take necessary precautions immediately.

&&

LAT...LON 3971 7623 3973 7610 3976 7606 3983 7604
      3987 7599 3995 7600 4004 7593 4011 7594
      4014 7588 4016 7590 4020 7586 4047 7558
      4016 7504 3986 7522 3984 7536 3977 7546
      3967 7551 3952 7564 3945 7577 3956 7609

$$

Kruzdlo
820 
WGUS81 KPHI 211950
FLSPHI

Flood Statement
National Weather Service Mount Holly NJ
250 PM EST FRI DEC 21 2018

DEC003-MDC015-PAC011-029-045-091-101-211959-
/O.CAN.KPHI.FA.W.0125.000000T0000Z-181221T2100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
New Castle DE-Cecil MD-Berks PA-Montgomery PA-Chester PA-
Philadelphia PA-Delaware PA-
250 PM EST FRI DEC 21 2018

...THE FLOOD WARNING HAS BEEN CANCELLED FOR NEW CASTLE...CECIL...
SOUTHEASTERN BERKS...MONTGOMERY...CHESTER...WESTERN PHILADELPHIA AND
DELAWARE COUNTIES...

The heavy rain has ended. The flood warning has been cancelled.

LAT...LON 3971 7623 3973 7610 3976 7606 3983 7604
      3987 7599 3995 7600 4004 7593 4011 7594
      4014 7588 4016 7590 4020 7586 4047 7558
      4016 7504 3986 7522 3984 7536 3977 7546
      3967 7551 3952 7564 3945 7577 3956 7609

$$

Kruzdlo

What forecasters said that day

The local office's own words before this areal flood warning went out, 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 this areal flood warning went out at Dec 21, 6:54 AM EST, 1 hour 10 minutes earlier.

Area forecast discussion, Dec 21, 6:54 AM EST, 1 hour 10 minutes before
Area Forecast Discussion
National Weather Service Mount Holly NJ
654 AM EST Fri Dec 21 2018

.SYNOPSIS...
Low pressure across the southeastern states this morning will
intensify as it moves northward through tonight. An associated cold
front will cross our area later tonight. High pressure will build to
our south Saturday night into Sunday, then two weak clipper systems
may track near our region Sunday night and Tuesday night. High
pressure then builds in especially for Wednesday.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
For the 630 PM update, adjusted the hourly temperature and dew points to
match the conditions and trends. A rather warm start to the day with
many areas experiencing temperatures into the 60s, which is about
30-40 degrees warmer than this time yesterday. Winds are still gusty
especially closer to the coast, however they have diminished enough
and thus the Wind Advisory has been cancelled. Periods of rain
continues, some of which is heavy and due to efficient runoff numerous
flood warnings have been issued. Lightning has been non-existent
thus far, however some instability is working northward and with
the radar imagery looking more convective we kept a slight chance
of thunder in for mostly areas east of I-95 this morning.

From the 351 AM discussion...
A full-latitude trough from the Midwest to the Gulf of Mexico will
gradually shift eastward today. An intense wind field is associated
with this feature, with a 120-knot 500 mb jet rounding the base
of the trough and starting to lift up the eastern side. The combination
of the robust wind field and strong low-level warm air advection
and short wave energy is resulting in large scale ascent and therefore
periods of rain this morning. An analysis early this morning shows
an axis of precipitable water nearing 2 inches advecting across
much of our region. This will result in times of heavy rain, especially
within any convective elements. There is some weak instability working
northward across Delmarva, and therefore some embedded thunder is
possible this morning especially near and east of I-95. As the main
low-level jet and associated strong warm air advection lifts north
of our area, the rain is expected to lessen and become more showery
by midday especially as a dry slot arrives this afternoon. The
heavy rain can lead to some flooding with some impacts for the
morning commute. Given the strength of the wind field, the rain/showers
are moving quite rapidly therefore this may lessen the heavy rain
threat and reduce any persistent training. Some training though
of heavier cells will result in locally heavier rain with an
enhanced flood threat, and this may be closer to the coast through
about midday.

As we go through the afternoon, some additional showers are expected
however this may shift westward some as the midlevel feature
approaches and the dry slot moves through. Some cooling aloft may
also result in some low-topped convection to our west or southwest
that could arrive into parts of our region later this afternoon into
the early evening. It is not all that clear how much instability
could develop and whether or not it will be enough to result in some
lightning.

The strong wind field coupled with a much warmer boundary layer
across much of the area is resulting in gusty winds. The strongest
winds have been mostly from the Philadelphia metro on south and
eastward, with some gusts to around 50 mph noted earlier. While all
areas within the wind advisory area may not technically reach
criteria, given the robust wind field and mixing we will maintain
the advisory through mid-morning.

As for the temperatures, a rather mild day is expected. A model
blend including the LAMP guidance was used for the hourly
temperatures, and high temperatures are mainly a MOS blend.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SATURDAY/...
The upper-level trough will move across the East tonight and start
to lift out as a 120-knot 500 mb jet lifts up its east side. This
will take deepening surface low pressure into eastern Canada, with
its trailing cold front crossing our area late tonight and early
Saturday morning. Associated with the trough axis and a ribbon of
lift, showers should be more active across the western areas in the
evening then taper off through the night. Cold enough air may not
arrive into the Poconos until after the showers end.

As for Saturday, low pressure moves farther away however a tight
pressure gradient will be present. Some cooling occurs and this will
allow more efficient mixing especially as the boundary layer warms
some. The forecast soundings show about 30 knots of wind present to
mix down, therefore have peak wind gusts very near this. Given the
cyclonic flow and residual moisture, there may be a fair amount of
clouds around until some drier air arrives toward evening. High
temperatures are a multi-model/continuity blend.

&&

.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
Winds will diminish quickly Saturday evening and into the
overnight hours. Flow aloft turns zonal through the beginning of
the week, however a couple shortwave troughs are forecast to
pass quickly across our region amid this flow regime, one being
Sunday night and the other being Tuesday night. These are
expected to bring couple of clipper systems across the region.
At this time, guidance varies on the intensity and placement of
these features and therefore how much precipitation, if any,
they produce. That being said, even the higher end of the
guidance is not very robust with accumulations. Therefore, kept
PoPs considerably low for both systems given lack of confidence
at this point. Thermal profiles will support mostly snow toward
the north and mostly rain toward the south with a rain/snow mix
somewhere along I-95. Sensible weather will remain seasonable
and fair between these systems.

High pressure builds in Wednesday under a ridge amplifying
across the eastern US. This will clear things out for our area
and bring in some colder and drier air. Another shortwave
approaches the area Thursday bringing an increasing chance for
showers throughout the day and the potential for widespread
rainfall again by Thursday night into Friday. Temperatures will
remain largely around normal through the entire extended period.

&&

.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY and surrounding areas.

Today...MVFR/IFR ceilings with visibilities varying from VFR to IFR at
times this morning with periods of rain at varying intensity.
The rain becomes more showery through the day and should tend to
decrease in coverage. Some thunder possible this morning and
then again later this afternoon, however the coverage looks to
be limited and therefore not included in the TAFs. Southeast to
south winds 10-15 knots with gusts up to 30 knots (highest
especially closer to the coast), then diminishing by later this
morning and through the afternoon.

Tonight...MVFR/IFR ceilings may improve to VFR for a time with showers
ending. South to southwest winds around 10 knots, becoming west
and increasing some toward daybreak Saturday. Low confidence
regarding the ceiling heights.

Saturday...Mainly VFR and drying out. West-northwest winds winds
15-20 knots with gusts to around 30 knots.

OUTLOOK...
Saturday night...VFR. West-northwest winds diminishing to 10 knots
or less.

Sunday and Monday...Mainly VFR. However, some rain and/or snow
showers possible Sunday night into Monday.

Tuesday...VFR expected. However, some light rain and/or snow
showers will be possible Tuesday night.

&&

.MARINE...
For the 630 AM update, replaced the Gale Warning with a Small Craft
Advisory for Delaware Bay and the adjacent Atlantic Coastal waters.
The advisory goes through tonight for now, as there is some potential
for some gales during Saturday. The remainder of the Gale Warning
remains as is for now.

From the 351 AM discussion...
Despite a robust wind field, strong low-level warm air advection
is reducing the depth of mixing. Some coastal wind gusts have
been to gale force while farther offshore the mixing thus far
has been less. We will keep the Gale Warning going for now,
expiring from south to north starting at 7 AM. Locally stronger
winds are possible with heavier showers or a thunderstorm. A
Small Craft Advisory will then be needed following the gales,
however there may be a period of low- end gale force gusts
Saturday afternoon.

OUTLOOK...
Saturday night...SCA conditions expected through the evening hours
with winds and seas subsiding to below SCA conditions through the
overnight hours.

Sunday and Sunday night...Sub-SCA conditions are expected.

Monday and Monday night...SCA conditions possible later in the
afternoon and evening hours.

Tuesday and Tuesday night...Sub-SCA conditions expected with
winds diminishing through the day.

&&

.HYDROLOGY...
On average, the heaviest precipitation is expected to fall through
early this afternoon. Regardless of model, they all show tropical
connectivity, a convective contribution, and well above normal PW's
for this time of year.

Total rainfall amounts of 1.5-3.0 inches are expected. Locally
higher amounts are possible, especially if any thunderstorms and
training occur. These amounts can be broken down further...1.50 to
2.50 inches south of the PA Turnpike and I-195 in NJ and 2.0 to 3.0
inches to the north.

Rainfall across specific basins...

Passaic - 2.50 to 3.00"
Raritan - 2.00 to 3.00"
Delaware north of Trenton - 2.00 to 3.00"
Delaware south of Trenton - 1.75 to 2.75"
Schuylkill and the rest of SE PA - 1.75 to 2.00"

Even without thunderstorms, a long duration rainfall event is
expected to lead to significant rises on many local creeks and
streams and even the larger rivers. The latest forecasts from MARFC
indicate that around 15 forecast points/gauges will reach at least
caution stage and a few (namely, Pine Brook, Macopin Dam, Boonton
below the dam, Pemberton, and Blackwells Mills) will reach flood
stage.

The Flood Watch continues. Nuisance poor drainage/low lying flooding
first followed by stream/river flooding, assuming the expected
rainfall comes to fruition. And if river flooding does occur, it
could likely last into the next week.

We fielded questions yesterday regarding our mainstem rivers.
Assuming the expected rainfall comes to fruition, portions of the
Passaic are the most likely to exceed flood stage followed by
portions of the Raritan. As of this afternoon, the heaviest rain is
forecast across the Passaic basin. As a result, moderate to major
flooding is possible. The last time portions of the Passaic River
experienced major flooding was during 2011 with Irene and Lee. The
flooding threat isn't as high for the Schuylkill or Delaware rivers.
At the moment, we are not seeing water levels reaching flood stage
on either river, but we can't rule out some locations getting as
high as action/caution stage.

A bit more regarding the Delaware...although water levels are not
expected to rise to flood stage at this time (signifying widespread
minor flooding), some nuisance flooding would be possible if some
gauges reach caution stage. When the Delaware runs high, it could
hinder/slow down flow on the Lehigh causing water levels to run a
bit higher. This could cause spotty minor flooding near and around
Easton. Further south, River Road in Pohatcong Township on the NJ
side is a low spot that can see some water as could PA 32 in Yardley
Borough.

The main message here is to keep an eye on future forecasts. Our
crests our dependent on rainfall. So if there is a shift in the
heavy rain, flooding will be worse in different locations that we
are currently highlighting (e.g. - the more significant flood
concerns in NJ attm could shift west if the axis of heavier rain
shifts west).

&&

.TIDES/COASTAL FLOODING...
The latest model forecasts continue to show minor to moderate flooding
for most locations on the Atlantic coast, Delaware Bay, and tidal
Delaware River around the time of high tide today. We remain concerned
that models are generally underforecasting tidal levels during
the high tide, as a result of a typical low bias models exhibit
in these regimes and the lack of accounting for expected rainfall.
The ESTOFS continues to trend higher than the ETSS, and the forecast
remains slightly higher than the ESTOFS because of the above-mentioned
concerns.

The most likely locations to reach moderate flooding are coastal
portions of Middlesex and Monmouth Counties, where a coastal Flood
Warning remains in effect this mornings high tide. Other locations
may require warnings should confidence increase in moderate
flooding; locations of greatest concern are Cape May and Delaware
Bay, given the favorable southeasterly surface flow. For now,
though, a Coastal Flood Advisory remains in effect for the
central/southern New Jersey coast, the Delaware Atlantic coast,
Delaware Bay, and the tidal Delaware River for the Friday daytime
high tide.

For the eastern shores of Chesapeake Bay, minor flooding is still a
possibility, but most models remain under advisory levels during the
high tide Friday.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...Flood Watch through late tonight for PAZ054-055-060>062-070-
     071-101>106.
     Coastal Flood Advisory from 10 AM this morning to 2 PM EST
     this afternoon for PAZ070-071-106.
NJ...Flood Watch through late tonight for NJZ001-007>010-012>027.
     Coastal Flood Advisory until 10 AM EST this morning for
     NJZ020>027.
     Coastal Flood Advisory until 11 AM EST this morning for NJZ016.
     Coastal Flood Advisory from 10 AM this morning to 2 PM EST
     this afternoon for NJZ015-017>019.
     Coastal Flood Warning until 11 AM EST this morning for
     NJZ012>014.
DE...Flood Watch through late tonight for DEZ001>004.
     Coastal Flood Advisory until 10 AM EST this morning for
     DEZ002>004.
     Coastal Flood Advisory until 11 AM EST this morning for DEZ001.
MD...Flood Watch through late tonight for MDZ008-012-015-019-020.
MARINE...Gale Warning until 10 AM EST this morning for ANZ452-453.
     Gale Warning until 4 PM EST this afternoon for ANZ450-451.
     Small Craft Advisory until 6 AM EST Saturday for ANZ430-431-
     454-455.

&&

Synopsis...Gorse/Staarmann
Near Term...Gorse
Short Term...Gorse
Long Term...Staarmann
Aviation...Gorse/MPS/Staarmann
Marine...Gorse/MPS/Staarmann
Hydrology...
Tides/Coastal Flooding...
Hazardous weather outlook, Dec 21, 6:40 AM EST, 1 hour 24 minutes before
Hazardous Weather Outlook
National Weather Service Mount Holly NJ
640 AM EST Fri Dec 21 2018

NJZ001-007>010-PAZ054-055-060>062-101>105-221145-
Sussex-Warren-Morris-Hunterdon-Somerset-Carbon-Monroe-Berks-Lehigh-
Northampton-Western Chester-Eastern Chester-Western Montgomery-
Eastern Montgomery-Upper Bucks-
640 AM EST Fri Dec 21 2018

...FLOOD WATCH IN EFFECT THROUGH LATE TONIGHT...

This Hazardous Weather Outlook is for northern New Jersey,
northwest New Jersey, east central Pennsylvania, northeast
Pennsylvania and southeast Pennsylvania.

.DAY ONE...Today and tonight.

Please listen to NOAA Weather Radio or go to weather.gov on the
Internet for more information about the following hazards.

   Flood Watch.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday.

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.

NJZ015-017>019-PAZ070-071-106-221145-
Mercer-Gloucester-Camden-Northwestern Burlington-Delaware-
Philadelphia-Lower Bucks-
640 AM EST Fri Dec 21 2018

...FLOOD WATCH IN EFFECT THROUGH LATE TONIGHT...
...COASTAL FLOOD ADVISORY IN EFFECT FROM 10 AM THIS MORNING TO 2 PM
EST THIS AFTERNOON...

This Hazardous Weather Outlook is for central New Jersey, southern
New Jersey and southeast Pennsylvania.

.DAY ONE...Today and tonight.

Please listen to NOAA Weather Radio or go to weather.gov on the
Internet for more information about the following hazards.

   Flood Watch.
   Coastal Flood Advisory.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday.

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.

DEZ001-NJZ016-221145-
New Castle-Salem-
640 AM EST Fri Dec 21 2018

...FLOOD WATCH IN EFFECT THROUGH LATE TONIGHT...
...COASTAL FLOOD ADVISORY IN EFFECT UNTIL 11 AM EST THIS MORNING...

This Hazardous Weather Outlook is for northern Delaware and
southern New Jersey.

.DAY ONE...Today and tonight.

Please listen to NOAA Weather Radio or go to weather.gov on the
Internet for more information about the following hazards.

   Flood Watch.
   Coastal Flood Advisory.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday.

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.

NJZ012>014-221145-
Middlesex-Western Monmouth-Eastern Monmouth-
640 AM EST Fri Dec 21 2018

...COASTAL FLOOD WARNING IN EFFECT UNTIL 11 AM EST THIS MORNING...
...FLOOD WATCH IN EFFECT THROUGH LATE TONIGHT...

This Hazardous Weather Outlook is for central New Jersey and
northern New Jersey.

.DAY ONE...Today and tonight.

Please listen to NOAA Weather Radio or go to weather.gov on the
Internet for more information about the following hazards.

   Coastal Flood Warning.
   Flood Watch.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday.

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.

DEZ002>004-NJZ020>027-221145-
Kent-Inland Sussex-Delaware Beaches-Ocean-Cumberland-Atlantic-
Cape May-Atlantic Coastal Cape May-Coastal Atlantic-Coastal Ocean-
Southeastern Burlington-
640 AM EST Fri Dec 21 2018

...COASTAL FLOOD ADVISORY IN EFFECT UNTIL 10 AM EST THIS MORNING...
...FLOOD WATCH IN EFFECT THROUGH LATE TONIGHT...

This Hazardous Weather Outlook is for central Delaware, southern
Delaware and southern New Jersey.

.DAY ONE...Today and tonight.

Please listen to NOAA Weather Radio or go to weather.gov on the
Internet for more information about the following hazards.

   Flood Watch.
   Coastal Flood Advisory.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday.

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.

MDZ008-012-015-019-020-221145-
Cecil-Kent MD-Queen Annes-Talbot-Caroline-
640 AM EST Fri Dec 21 2018

...FLOOD WATCH IN EFFECT THROUGH LATE TONIGHT...

This Hazardous Weather Outlook is for northeast Maryland.

.DAY ONE...Today and tonight.

Please listen to NOAA Weather Radio or go to weather.gov on the
Internet for more information about the following hazards.

   Flood Watch.

Some minor coastal flooding is possible today.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday.

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.

ANZ452-453-221145-
Coastal waters from Little Egg Inlet to Great Egg Inlet NJ out 20 nm-
Coastal waters from Great Egg Inlet to Cape May NJ out 20 nm-
640 AM EST Fri Dec 21 2018

...GALE WARNING IN EFFECT UNTIL 10 AM EST THIS MORNING...

This Hazardous Weather Outlook is for Atlantic coastal waters.

.DAY ONE...Today and 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...Saturday through Thursday.

Gale force wind gusts are possible on Saturday.

.SPOTTER INFORMATION STATEMENT...

Weather spotters are encouraged to report significant weather
conditions according to standard operating procedures.

ANZ450-451-221145-
Coastal waters from Sandy Hook to Manasquan Inlet NJ out 20 nm-
Coastal waters from Manasquan Inlet to Little Egg Inlet NJ out 20 nm-
640 AM EST Fri Dec 21 2018

...GALE WARNING IN EFFECT UNTIL 4 PM EST THIS AFTERNOON...

This Hazardous Weather Outlook is for Atlantic coastal waters.

.DAY ONE...Today and 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...Saturday through Thursday.

Gale force wind gusts are possible on Saturday.

.SPOTTER INFORMATION STATEMENT...

Weather spotters are encouraged to report significant weather
conditions according to standard operating procedures.

ANZ430-431-454-455-221145-
Delaware Bay waters north of East Point NJ to Slaughter Beach DE-
Delaware Bay waters south of East Point NJ to Slaughter Beach DE-
Coastal waters from Cape May NJ to Cape Henlopen DE out 20 nm-
Coastal waters from Cape Henlopen to Fenwick Island DE out 20 nm-
640 AM EST Fri Dec 21 2018

This Hazardous Weather Outlook is for Atlantic coastal waters and
Delaware Bay Waters.

.DAY ONE...Today and tonight.

The probability of widespread hazardous weather is low.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday.

Gale force wind gusts are possible on Saturday.

.SPOTTER INFORMATION STATEMENT...

Weather spotters are encouraged to report significant weather
conditions according to standard operating procedures.

In the hours before

Local storm report, Dec 21, 7:48 AM EST, 16 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
748 AM EST FRI DEC 21 2018

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0732 AM     FLOOD            1 SSW EDDINGTON         40.07N 74.95W
12/21/2018                   BUCKS              PA   DEPT OF HIGHWAYS

            FLOODING NEAR STATION AVENUE AND STATE ROAD
            IN BENSALEM TWP. SEVERAL ROADS CLOSED.

&&

CMS
Local storm report, Dec 21, 7:53 AM EST, 11 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
753 AM EST FRI DEC 21 2018

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0737 AM     FLOOD            1 SW ANCIENT OAKS       40.53N 75.60W
12/21/2018                   LEHIGH             PA   DEPT OF HIGHWAYS

            SPRING CREEK RD. BETWEEN PA-100 AND
            TREXLERTOWN RD. CLOSED DUE TO FLOODING.

&&

JEO
Local storm report, Dec 21, 7:54 AM EST, 10 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
754 AM EST FRI DEC 21 2018

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0734 AM     FLOOD            2 SSW MARTINSVILLE      40.58N 74.57W
12/21/2018                   SOMERSET           NJ   DEPT OF HIGHWAYS

            FLOODING ON U.S. HIGHWAY 22 NEAR THE
            INTERSTATE 287 JUNCTION. LANE RESTRICTIONS
            IN PLACE.

&&

CMS
Local storm report, Dec 21, 7:57 AM EST, 7 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
757 AM EST FRI DEC 21 2018

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0735 AM     FLOOD            1 ENE PAULSBORO         39.83N 75.22W
12/21/2018                   GLOUCESTER         NJ   DEPT OF HIGHWAYS

            FLOODING ON STATE HIGHWAY 44 NEAR PARADISE
            ROAD IN WEST DEPTFORD TWP. LANE RESTRICTIONS
            IN PLACE.

&&

CMS
Special weather statement, Dec 21, 8:03 AM EST, 1 minute before
Special Weather Statement
National Weather Service Mount Holly NJ
803 AM EST Fri Dec 21 2018

NJZ012>014-020-026-027-211415-
Middlesex-Western Monmouth-Eastern Monmouth-Ocean-Coastal Ocean-
Southeastern Burlington-
Including the cities of New Brunswick, Freehold, Sandy Hook,
Jackson, Long Beach Island, and Wharton State Forest
803 AM EST Fri Dec 21 2018

An area of moderate to heavy rain will continue to lift north
along the New Jersey shore. Southeast winds will range from 20 to
25 mph with gusts as high as 35 mph. Please continue to heed any
Flood Warnings that may be in effect.

MPS
Local storm report, Dec 21, 8:04 AM EST, 0 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
804 AM EST FRI DEC 21 2018

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0750 AM     FLOOD            1 N RITTENHOUSE SQUARE  39.96N 75.17W
12/21/2018                   PHILADELPHIA       PA   DEPT OF HIGHWAYS

            FLOODING ON INTERSTATE 676 NEAR BEN FRANKLIN
            PARKWAY. LANE RESTRICTIONS IN PLACE.

&&

CMS

The office that day

Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Dec 21, 3:44 AM ESTRiver Flood WarningPHIChester9 hr
Dec 21, 4:02 AM ESTAreal Flood WarningPHIBerks, Chester, Delaware, Montgomery, Philadelphia4 hr
Dec 21, 4:09 AM ESTAreal Flood WarningPHIBucks, Lehigh, Northampton16 hr
Dec 21, 4:27 AM ESTAreal Flood WarningPHIBerks, Carbon, Lehigh, Monroe, Northampton8 hr
Dec 21, 4:36 AM ESTAreal Flood WarningPHIBucks, Montgomery, Philadelphia7 hr
Dec 21, 5:10 AM ESTRiver Flood WarningPHIDelaware5 hr
Dec 21, 5:20 AM ESTRiver Flood WarningPHIChester, Delaware14 hr
Dec 21, 8:51 AM ESTRiver Flood WarningPHIBucks6 hr
Dec 21, 12:15 PM ESTAreal Flood WarningPHIBerks, Carbon, Lehigh, Monroe, Northampton4 hr
Dec 21, 3:55 AM ESTRiver Flood WarningPHINew Castle6 hr
Dec 21, 4:14 AM ESTRiver Flood WarningPHINew Castle6 hr
Dec 21, 4:43 AM ESTAreal Flood WarningPHIKent, New Castle, Sussex8 hr
Dec 21, 5:02 AM ESTRiver Flood WarningPHINew Castle5 hr

Nearby

Areal Flood Warnings in Pennsylvania, 2018Areal Flood Warnings in Delaware, 2018Areal Flood Warnings in Maryland, 2018Every areal flood warning in 2018

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.