Marine Weather and Tide Forecast for Colwyn, PA

NEAR TERM /THROUGH TODAY/
Canadian high pressure will be in control through Friday, sliding from the Great Lakes into the Carolinas resulting in a rather nice but somewhat chilly end of the week. Expecting mostly clear and sunny skies through Friday with perhaps a few passing clouds.

The main story tonight will be the first frost of the season.
Mostly clear skies (good for aurora viewing) and winds becoming light will allow for ideal radiational cooling conditions. Not many changes were made, other than adding Camden and Gloucester County to the Frost Advisory, as rural areas in the southeastern half of the county could see some frost developing. Other than that, a Frost Advisory remains in effect for tonight for most of our PA zones outside of Philly and all New Jersey zones away from the immediate coast. Overnight lows will be in the mid to upper 30s, with low 40s around Philly and at the coast. A few of the typical cold spots will probably dip to near freezing.

For tomorrow, sunny skies and highs in the mid to upper 60s. A nice way to close out the week.

SHORT TERM /TONIGHT THROUGH SUNDAY NIGHT/
High pressure will remain situated south of the region on Friday night before moving off the coast of the Southeast US on Saturday into Saturday night. At the same time, a cold front will approach from the northwest on Saturday but will be dying out as it crosses and eventually stalls over our region. As a result, no precipitation is expected with plentiful sunshine and clear skies through at least Saturday night. Low temps will be rather seasonable in the upper 40s to mid 50s with highs on Saturday mainly in the 70s.

For Sunday and into Sunday night, an area of low pressure will develop over the Midwest and ride eastward along the aforementioned stalled boundary. This should result in the boundary lifting north as warm front. Shower activity should increase across portions of the region especially during the afternoon and evening, mainly from the I-95 corridor north and west, with the highest PoPs found over the Lehigh Valley, Poconos and northern NJ (30-50%). South and east of the I-95 corridor, PoP's drastically decrease toward the coast (10-30%).
However, as noted by the previous shift, there still is some variance on how far the north the boundary lifts. If the boundary lifts further north, then little in the way of precip may occur along with some warmer temps on Sunday. If the boundary remains closer to the region, then more in the way of showers are expected with cooler temps on Sunday. Shower activity will begin to wane late Sunday night as the low departs.

LONG TERM /MONDAY THROUGH THURSDAY/
The long term period relatively remains unchanged as a whole.
The only notable weather feature worth mentioning is the cold front that crosses through the region on Monday. This will usher in a very dry and cool air mass through the middle of next week as a large and expansive area of high pressure develops over the Central US. This will keep the region dry under a northwest surface flow for the period. Temps will be seasonably cool on average of 5-10 degrees below normal. This will yield several opportunities for frost and potentially freeze headlines across portions of the area next week.

AVIATION /06Z FRIDAY THROUGH TUESDAY/
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY and surrounding areas.

Tonight...VFR/SKC. West/northwest winds around 5 kt or less.
High confidence.

Friday...VFR. West/northwest winds around 5-10 kt. High confidence.

Outlook...

Friday night through Tuesday...VFR expected through the period.
Slight chance of sub-VFR conditions possible late Sunday into Sunday night for KRDG/KABE with a chance for rain showers.
Otherwise, no significant weather is expected.

MARINE
Through Friday, no marine headlines are expected with west/northwest winds around 10-20 kt and seas 2 to 4 feet.

Outlook...

Friday night through Saturday night...No marine headlines expected. Fair weather.

Sunday through Monday...SCA conditions probable for both the Delaware Bay and Atlantic Ocean waters due to winds and seas associated with cold frontal passage. Rain showers possible.

Monday night through Tuesday...SCA conditions may linger into Monday night on the ocean waters, otherwise conditions should generally remain below SCA thresholds.

PHI WATCHES/WARNINGS/ADVISORIES
PA...Frost Advisory until 9 AM EDT this morning for PAZ054-055- 060>062-101>106.
NJ...Frost Advisory until 9 AM EDT this morning for NJZ001-007>010- 012-013-015>023-027.
DE...None.
MD...None.
MARINE...None.