Marine Weather Net

Cape May NJ to Cape Henlopen DE out 20 nm Marine Forecast


TODAY

SE
WINDS
5 - 10
KNOTS

TONIGHT

S
WINDS
10 - 15
KNOTS

SUN

S
WINDS
20 - 25
KNOTS

SUN NIGHT

W
WINDS
30 - 35
KNOTS

The Marine Weather Forecast In Detail:
ANZ454 Forecast Issued: 702 AM EST Sat Feb 15 2025

SMALL CRAFT ADVISORY IN EFFECT FROM 7 PM EST THIS EVENING THROUGH LATE TONIGHT ...GALE WARNING IN EFFECT FROM SUNDAY MORNING THROUGH MONDAY EVENING...
Today...Se Winds 5 To 10 Kt. Seas 2 To 3 Ft. Wave Detail: S 2 Ft At 3 Seconds And E 2 Ft At 5 Seconds. A Chance Of Rain Early This Afternoon. Rain Late.
Tonight...S Winds 10 To 15 Kt With Gusts Up To 25 Kt. Seas 3 To 5 Ft. Wave Detail: Se 5 Ft At 10 Seconds And S 3 Ft At 5 Seconds. Rain.
Sun...S Winds 20 To 25 Kt, Becoming Sw 25 To 35 Kt In The Afternoon. Seas 5 To 8 Ft, Building To 8 To 11 Ft In The Afternoon. Wave Detail: S 8 Ft At 8 Seconds, Becoming S 11 Ft At 9 Seconds. Showers.
Sun Night...W Winds 30 To 35 Kt With Gusts Up To 45 Kt. Seas 7 To 10 Ft. Wave Detail: S 10 Ft At 10 Seconds And W 8 Ft At 6 Seconds.
Mon...W Winds 30 To 35 Kt With Gusts Up To 45 Kt. Seas 5 To 8 Ft. Wave Detail: W 8 Ft At 6 Seconds And Se 4 Ft At 10 Seconds.
Mon Night...W Winds 25 To 30 Kt With Gusts Up To 40 Kt, Becoming Nw 20 To 25 Kt With Gusts Up To 30 Kt After Midnight. Seas 4 To 6 Ft. Wave Detail: Nw 6 Ft At 6 Seconds And Se 2 Ft At 10 Seconds.
Tue...Nw Winds 15 To 20 Kt. Seas 3 To 4 Ft.
Tue Night...Nw Winds Around 15 Kt. Seas 2 To 4 Ft.
Wed...N Winds 10 To 15 Kt. Seas Around 2 Ft. A Chance Of Snow. Vsby 1 To 3 Nm.
Wed Night...N Winds 10 To 15 Kt, Becoming Ne 15 To 20 Kt After Midnight. Seas 2 To 3 Ft. Snow Likely. Vsby 1 To 3 Nm.
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Area Forecast Discussion
National Weather Service Mount Holly NJ
628am EST Sat Feb 15 2025

Synopsis
High pressure in place across the region will shift offshore today. A strong low pressure system will impact the region over the weekend, bringing widespread precipitation. A strong cold front will pass offshore late Sunday, with windy conditions developing through Monday as arctic high pressure builds in from the west across the Great Lakes. Below normal temperatures are expected next week. A coastal system may impact the region late Wednesday into Thursday.

Near Term - Through Sunday
The storm system that will be affecting our region today through tomorrow will bring multiple weather hazards to our region, including wintry precipitation, locally heavy rain, isolated thunderstorms, and gusty winds.

No significant changes with the early morning update. As of 6 AM, light precipitation is sliding eastward across western PA. However, still not expecting the precipitation to start in our region until closer to mid day. Dry air is still in place over our region (dewpoints in the lower teens and even single digits across our area this morning), so even as we start to get light radar returns over our region, it will take some time for the boundary layer to support snow reaching the ground.

Synoptic and mesoscale mid and upper level trough currently near the Rockies will translate eastward, moving offshore of the East Coast Sunday night, with phasing polar and sub tropical jets as the system evolves. At the surface, a closed lee side low currently centered over the southern Plains will progress into western PA/eastern OH by Sunday morning and eventually into New England by late Sunday. As it progresses northeastward it will deepen and intensify. The low is anticipated to drop well below 990 mb. A warm front associated with this low will lift north into the area early Sunday, then the associated strong cold front will follow late Sunday.

Strong isentropic ascent will result in precipitation spreading into the region fairly quickly this afternoon well ahead of the main surface low. Some spotty flurries or sprinkles are possible in the morning, but any precipitation will likely struggle to reach the ground initially with the very dry airmass in place ahead of this system. Steady precipitation is expected this afternoon through most of tonight. As the center of the low makes its closest approach late tonight into early Sunday morning, we could see some breaks in the precipitation as our region is in a prime location for the dry slot (albeit briefly).

The last round of precipitation (all rain by this point) will come with and just ahead of the cold front late Sunday.

Impacts discussion:

Wintry Weather: The main concern for wintry weather impacts is for areas near and north of the Interstate 78 corridor. In these areas, although snow accumulations are expected to be barely advisory level (or in some cases below the guidance for advisories), the main impacts are going to be coming with the period of sleet and freezing rain in between the snow and the change over to all rain. For most of the advisory area, snow amounts of 1 to 3 inches with additional ice amounts of a few hundredths of an inch are possible. The exception is the southern Poconos and far NW New Jersey where in higher elevations, temperatures could stay below freezing through early Sunday morning. Consequently, ice amounts of up to three tenths of an inch are possible in the higher terrain of these areas. The combination of the snow and ice will create slippery conditions. In areas that get more ice accumulation, some minor tree and wire is possible. The good news is that conditions will improve quickly once the temperature gets above freezing, as with rain continuing to fall, any ice and snow should melt quickly.

Further south and east, including the Interstate 95 corridor, a period of snow, even very light accumulating snow, is possible, but should see a change over to all rain by early evening (for portions of the coastal plains, there may only be a brief period of a rain and snow mix before the change over to all rain). Due to the limited duration of wintry precipitation in these areas, impacts should be very limited.

Heavy Rain/flooding threat: A widespread 1 to 2 inches of total liquid equivalent precipitation (from today through the end of the day on Sunday) is still expected. Overall, we're not expecting a widespread flooding threat as river and stream levels mostly remain relatively low. Additionally, the snow pack from the storm earlier this week has melted and had a chance to absorb/runoff already. Additionally, the potential for a break in the precip, or at least lighter precip, on Sunday morning with the dry slot would further help limit the flooding threat. That being said, this could still be enough to cause some localized flooding especially for poor drainage areas. For the area waterways, the focus is on the Millstone River which tends to be one of the fastest responding waterways in our region, and is currently forecast to get close to flood stage by Sunday evening.

Thunderstorms: Isolated thunderstorms will be possible Sunday morning, and with the final round of showers that comes in with the cold front. Instability is limited, but there will be ample shear in place. There is a marginal risk for severe storms with strong winds. That being said, winds will be a threat even outside of thunderstorms, so will message this within the broader high wind watch (see more information on the high wind watch in the short term section below).

Short Term - Sunday Night Through Monday Night
Potentially significant impacts possible from a high wind event expected to impact the region late Sunday afternoon through Monday.

Following the weekend system, strong arctic high pressure will build into the region into the new week with below normal temperatures, windy, and dry conditions expected through Monday night.

In the wake of the strong cold front late Sunday afternoon into Sunday night, temperatures will plummet from the 50s to near 60 degrees into the 30s then 20s with wind chills in the teens. The main concern for late Sunday afternoon and evening through Monday will be the strong to damaging west to northwest winds developing.

The synoptic pattern is very favorable for high winds. Surface pressure rises exceeding 1 mb/hour, perhaps as much as 8 mb within just 3 hours, and very strong cold advection will support efficient boundary layer mixing immediately in the wake of the frontal passage and overnight into Monday. A consensus of deterministic BUFKIT profiles and HREF ensemble profiles indicate boundary layer mixing through the 925 mb layer, and perhaps as high as the 850 mb layer at times. Wind speeds at these levels around 35-50 kts should serve as a good proxy for wind gusts given the efficient mixing. 925 mb winds likely serving as a more prevailing wind gust proxy, with 850 mb winds serving as a peak gust proxy. This will translate to frequent westerly gusts in the 45-60 mph range across the entire area, with the strongest winds most likely occurring across the higher elevations and near the coasts.

Strong winds with gusts 40-50 mph could develop across the coastal plain ahead of the frontal passage late Sunday morning and early afternoon. Gusts during this timeframe would be around 40-50 mph at most from the south or southwest. The peak gusts of the event near 50-60 mph are likely to occur immediately in the wake of the frontal passage, which is expected to occur sometime Sunday afternoon to early evening. This will be when the aforementioned boundary layer wind speeds are strongest and surface pressure rises are sharpest. Thereafter, westerly gusts of 40-55 mph will likely prevail for much of Sunday night through at least the first half of Monday before beginning to subside. We have issued a High Wind Watch From Sunday through Monday to highlight the potential for an extended period of impacts from high winds.

While the peak gusts upwards of 60 mph are not expected to prevail during the entire watch period, wet soils combined with the high winds could result in extensive tree damage through the event. Additionally, the strong winds will usher in much colder air, with temperatures in the 20s and 30s and wind chills in the teens. We are most concerned about the potential for power outages combined with the cold, which could exacerbate the impacts of this high wind event for folks that lose power with it being so cold out. Please take this event seriously!

As previously mentioned, low temperatures Sunday night into Monday morning will be mainly in the 20s with wind chills dropping into the teens. Temperatures will struggle to climb from morning minimums on Monday, with highs mainly in the 30s and maximum wind chills in the teens and 20s. Winds will lessen into Monday night, though remaining blustery with lows mainly in the teens to near 20 degrees. Minimum wind chills will be mainly in the single digits. We should stay above Cold Weather Advisory criteria, however one may be considered due to impacts if widespread power outages are still an issue.

Long Term - Tuesday Through Friday
The main stories for the Long Term period are the continued below normal temperatures due to arctic high pressure remaining in place, as well as the potential for a coastal system to bring widespread snowfall accumulations to the region late Wednesday through Thursday.

Temperatures will remain roughly 10-15 degrees below normal from Tuesday through the end of the week. This will mean highs ranging from the mid 20s to mid 30s and lows in the teens to near 20 degrees in most areas. Daytime wind chills only topping out in the teens and 20s and nighttime wind chills dropping into the teens to single digits. Conditions will remain fairly breezy as well.

For Wednesday night through Thursday, confidence is increasing that widespread snowfall could occur across the region. The medium range guidance generally remains supportive of a synoptic pattern favorable for a coastal system. We are still about 5 days away from this period, so there is still a lot of uncertainty and time for snowfall potential to change. The evolution of any impacts from this system should begin to come into better focus following the departure of the weekend storm.

Marine
Winds and seas will stay below SCA (Small Craft Advisory) criteria through the day today. Starting tonight, southeasterly and southerly winds will increase. Though this is typically an unfavorable flow regime for gale force gusts, a very strong low level jet is expected to be just above the surface on Sunday, so winds up to to 35 kt will be possible through the morning. An abrupt wind shift (to westerly winds) and quick increase in winds is expected with a cold front which should move over the waters late in the day.

Outlook... Sunday night through Monday night...Gale force W to NW winds 30-40 kts following a strong cold frontal passage late afternoon or early evening Sunday. Gusts up to 45 kts. Seas 5-9 feet. Gale Warning remains in effect for this period. A brief period of westerly wind gusts near 50 kts is possible between 4 PM through 10pm Sunday as a strong cold front passes offshore. Low water levels could make navigation difficult around the times of low tide.

Tuesday...Small craft advisory conditions likely, with gusts of 25-30 kts. Seas 3-5 feet. Low water levels could make navigation difficult around the times of low tide.

Wednesday...No marine hazards expected.

NOAA Mount Holly NJ Office: Watches - Warnings - Advisories
PA...High Wind Watch from Sunday morning through Monday afternoon for PAZ070-071. High Wind Watch from Sunday afternoon through Monday afternoon for PAZ054-055-060>062-101>106. Winter Weather Advisory from noon today to 1am EST Sunday for PAZ061-062. Winter Weather Advisory from noon today to 10pm EST this evening for PAZ060-103-105. Winter Weather Advisory from noon today to 10am EST Sunday for PAZ054-055. NJ...High Wind Watch from Sunday morning through Monday afternoon for NJZ013-014-016>027. Winter Weather Advisory from noon today to 4am EST Sunday for NJZ001-008. High Wind Watch from Sunday afternoon through Monday afternoon for NJZ001-007>010-012-015. Winter Weather Advisory from noon today to 1am EST Sunday for NJZ007. Winter Weather Advisory from noon today to 10pm EST this evening for NJZ009-010. DE...High Wind Watch from Sunday morning through Monday afternoon for DEZ001>004. MD...High Wind Watch from Sunday morning through Monday afternoon for MDZ012-015-019-020.

Marine
Gale Warning from 6am Sunday to 10pm EST Monday for ANZ430- 431-450>455. Small Craft Advisory from 7pm this evening to 6am EST Sunday for ANZ450>455.