Overnight:
Patchy fog after 5am. Partly cloudy, with a low around 66. South wind around 5 mph.

Saturday:
Showers and thunderstorms likely after 10am. Some of the storms could produce heavy rain. Partly sunny, with a high near 89. Southwest wind 1 to 7 mph. Chance of precipitation is 60%. New rainfall amounts between a tenth and quarter of an inch possible.

Saturday Night:
Showers and thunderstorms likely before 11pm, then showers and thunderstorms likely between 11pm and 2am, then scattered showers and thunderstorms. Some of the storms could produce heavy rain. Mostly cloudy, with a low around 67. Southwest wind 2 to 6 mph. Chance of precipitation is 60%. New rainfall amounts between a quarter and half of an inch possible.

Sunday:
Scattered showers and thunderstorms before 11am, then showers and thunderstorms likely between 11am and 2pm, then showers and thunderstorms likely. Cloudy, with a high near 77. South wind around 2 mph. Chance of precipitation is 70%. New rainfall amounts between a half and three quarters of an inch possible.

Sunday Night:
Showers and thunderstorms likely. Cloudy, with a low around 61. East wind 3 to 8 mph. Chance of precipitation is 70%. New rainfall amounts between a quarter and half of an inch possible.

Memorial Day:
A slight chance of rain showers before 8am, then a chance of showers and thunderstorms. Mostly cloudy, with a high near 78. Chance of precipitation is 30%. New rainfall amounts less than a tenth of an inch possible.

Monday Night:
A chance of showers and thunderstorms before 8pm. Mostly cloudy, with a low around 64. Chance of precipitation is 30%.

Tuesday:
Partly sunny, with a high near 84.

Extended Forecast

Tuesday Night Mostly Cloudy	Wednesday Thunderstorm	Wednesday Night Thunderstorm	Thursday Thunderstorm	Thursday Night Thunderstorm	Friday Thunderstorm
Lo ≈62°F	Hi ≈79°F	Lo ≈61°F	Hi ≈77°F	Lo ≈63°F	Hi ≈77°F
			PoP 40%	PoP 40%	PoP 50%

AREA FORECAST DISCUSSION
National Weather Service Mount Holly NJ
930 PM EDT Fri May 25 2018

Weather Synopsis:
High pressure will be centered well east of the Mid-Atlantic coast through the holiday weekend. A cold front moves southward across our area late Saturday night and Sunday, then stalls in our area into Monday. A secondary cold front moves through later Monday night into Tuesday, followed by high pressure Tuesday night before it moves offshore during Wednesday. A warm front may approach on Thursday followed by a cold front later Friday.

Near Term:
UNTIL 6 AM SATURDAY MORNING - High pressure located over the western North Atlantic will maintain a southwest flow in our region overnight. Wind speeds are expected to diminish and the humidity will be on the increase. Patchy fog is possible.

Minimum temperatures are anticipated to favor the 60s.

Short Term:
6 AM SATURDAY MORNING THROUGH 6 PM SATURDAY - A hot and humid day on tap for Saturday as southwest flow allows for a tropical airmass to build into the region throughout the day. Meanwhile, an upper trough with several strong shortwaves will approach during the day and move across the region in the afternoon and evening.

Highs will top off in the mid and upper 80s, with highs around 90 along the I-95 corridor from Newark to Philly, and in inland areas of the Delmarva. Surface dewpoints will climb into the mid and upper 60s in the southern Poconos and northern NJ, and in the upper 60s to around 70 across southern NJ, southeast PA, and the Delmarva.

As that upper trough approaches, scattered showers and thunderstorms will develop over the Mid-Atlantic, and creep their way north and east into the Delaware Valley and Delmarva, but the stronger thunderstorms will develop later in the afternoon and in the evening. CAPE values will approach 2000 J/kg, and the lifted index will be around -4C. 0-6km Bulk Shear is only 15-20 kt, so not expecting a widespread severe weather outbreak. However, for the southern areas, PWATs will increase to around 2" in the afternoon, and this could result in heavy rain which could lead to urban and small stream flooding in some spots.

Long Term:
SATURDAY NIGHT THROUGH FRIDAY - Summary...Unsettled conditions at times for the second half of the holiday weekend (especially Sunday) along with some cooling. Potentially unsettled again for the second half of next week.

Synoptic Overview...The flow pattern is advertised to become less progressive with a closed low in the West, a trough near the Gulf Coast and ridge from the Midwest to the southern plains. This should break down some as we go through early next week, although weak steering flow keeps a system in the central Gulf Coast states for awhile. A trough sliding by will allow a cold front to sag southward across much of our area through Sunday before it gradually weakens or dissipates. Tropical moisture is forecast be in place ahead of the southbound cold front, and weak surface low developing along this front may enhance the frontal zone for a time. The continued theme in the overall guidance shows showers/storms across our area through Sunday, then probably some drying Monday. The trough in eastern Canada and the Northeast amplifies some Monday into Tuesday, then some ridging aloft looks to slide eastward Wednesday before a possible upper-level trough arrives for the end of the week. The second half of next week is less certain with the details as this will depend especially on energy associated with the Gulf Coast system.

For Saturday night and Sunday...Showers and some thunderstorms are expected to continue Saturday night despite the loss of daytime heating, since short wave energy will be moving across the area and will continue to be fed by high precipitable water from the south. A front from the north will be sagging into the far northern portions of our area late Saturday night. Some very heavy rain may result in a local flood threat, especially as convection may take on some training or backbuilding characteristics. It will be a very warm and muggy night for most areas.

There will be additional convection on Sunday especially in the afternoon and evening as the surface cold front sags farther southward which should provide a bit more convergence. While the deeper tropical moisture plume may reside just to our south, plenty of moisture in our area combined with possible slower storm motion and training may result in a local very heavy rain/flood threat. The extent of this is of lower confidence at this time as some dry will be trying to work in from the northeast. Temperatures should tend to fall some during Sunday (especially afternoon) from northeast to southwest as the front settles southward. As this occurs, the thunder chances should diminish across the northern areas where a more stable marine layer should advect in and this continues Sunday night.

For Monday and Tuesday...A short wave trough sliding across the Northeast Monday will take surface low pressure southeast of Cape Cod. Low pressure tracking east of Hudson Bay Canada has a cold front attached to it, and this front is forecast to move through Monday night into Tuesday. While a few showers/thunder cannot be ruled out on Monday, it may end up being mostly dry as the frontal zone works back northeastward as a warm front (low clouds/drizzle perhaps to start Monday). This should set the stage for a much warmer Tuesday after a cooler Monday. Some convection is possible Tuesday but this may end up depending on the timing of the actual cold front as high pressure begins to build southeastward from Canada.

For Wednesday through Friday...A trough aloft across the Gulf Coast is forecast to gradually lift north and northeastward. As this occurs, a ridge to its north slides eastward, allowing surface high pressure over our area to start Wednesday to shift offshore. The center of the high should be to our northeast for a time, resulting in a northeast to east surface flow before it veers more from the southeast. A front is forecast to be lurking to our south with tropical moisture residing to its south, therefore the placement of this will be key regarding any shower/thunder chances for parts of our area. Much of this may be held off just to our south and west as the main moisture plume and instability axis is initially placed there. With time though, the influence of the incoming upper-level trough and remnant tropical system should result in increasing convective chances Thursday and Friday. A cold front is forecast to be arriving from the northwest during Friday, which may assist in focusing showers/thunderstorms.

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