textproduct: Philadelphia/Mt Holly

SYNOPSIS

High pressure moves away this morning ahead of an arctic front passing through the region later this afternoon and evening. A cold Canadian high pressure system follows and it will dominate the forecast through the end of the work week. The next chance of widespread precipitation doesn't look to arrive until at least next weekend.

NEAR TERM /THROUGH TONIGHT/

As of 9:30am...An expansive strato-cu deck continues to overspread the area ahead of the cold front which currently lies back over northwest Pennsylvania. Given atmospheric profiles and current satellite imagery, have significantly increased cloud cover for much of the afternoon with the mid-morning update. So now, expect mostly cloudy to overcast skies for most, with mostly sunny skies really limited to coastal areas. Otherwise, previous discussion is below:

High pressure will retreat this morning as a cold front passes through the region this afternoon and into the evening. A relatively tranquil day is expected as a whole. No precipitation is expected as the cold front is moisture deprived. High temperatures should generally top out in the mid 30s to mid 40s. Winds also increase today. This morning, we see winds 5-10 mph. By tonight, the gusts start to reach upwards of 20-30 mph. Our overnight lows range from the mid teens to mid 20s, so when factoring in the wind, we'll have wind chills in the single digits and teens.

SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/

Following the frontal passage, cold Canadian high pressure will begin to slowly work its way towards our region as it builds out of the high plains. This will usher in a reinforcing cold airmass through the short term forecast period. A modest pressure gradient will also develop over the region on Tuesday, so Tuesday looks to be quite breezy. Have continued to blend in higher wind guidance due to the cold air advection push behind the front. So continue to think that we'll see wind gusts upwards of 30-35 mph during the afternoon. High temps will also be noticeably cooler compared to Monday; mainly upper 20s, so most places will struggle to reach the freezing mark for Tuesday afternoon. Combined with the gusty conditions, wind chill values will be in the teens during the afternoon.

The cold air advection push continues for Tuesday night, with lows falling into the teens for the majority of the area. On top of that, winds will remain quite gusty upwards of 30-35 mph despite the loss of diurnal mixing. As a result, wind chills will be in the single digits to near 0 degrees for most and as cold as -5 degrees in the Poconos. Will continue to monitor wind chills over the next few forecast cycles to see if a Cold Weather Advisory is warranted. Also, cannot rule out a rogue snow shower across the Pocono Plateau.

Wednesday will virtually be a rinse and repeat of Tuesday as high pressure moves into the Midwest. Temperatures will be a few degrees warmer though, topping out in the low 30s. Gusty winds up to 30-35 mph will continue however, as the pressure gradient remains overhead.

LONG TERM /THURSDAY THROUGH SUNDAY/

High pressure will gradually shift from the Midwest to Southeast US through the end of the work week, keeping the forecast dry through Friday. The only exception is a slight chance of snow showers on Thursday, most likely confined to the Poconos, with a shortwave aloft passing by. Below normal temperatures will continue through Thursday with temperatures returning close to normal on Friday.

For Saturday and Sunday, there continues to be signals from both global deterministic and ensemble guidance for some unsettled weather to return to the area. Low pressure looks to pass to our north, allowing above normal temperatures to return for Saturday. Eventually a cold front does look to cross through the area on Sunday, as temperatures return closer to normal. In terms of precipitation type, any precipitation will most likely be in the form of rain with frozen precipitation generally limited to the Pocono region.

AVIATION /15Z MONDAY THROUGH FRIDAY/

The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY and surrounding areas...

Monday... VFR expected. BKN/OVC stratocumulus deck expected from the I-95 corridor and terminals north and west. SCT/BKN ceilings mainly at KACY/KMIV. Winds pick up out of the southwest around 5-10 kt with gusts around 15-20 kt by mid- afternoon. High confidence.

Monday Night...VFR. Westerly winds 5-10 kt with gusts around 15-20 kt, becoming WNW after midnight. High confidence.

Outlook...

Tuesday through Wednesday night...VFR. Gusty winds up to 30 kts possible on Tuesday and Wednesday. Otherwise, no significant weather expected.

Thursday through Friday...VFR. No significant weather expected.

MARINE

Winds and seas will remain below Small Craft Advisory criteria for Monday with fair weather expected. This evening, winds will increase out of the southwest with some gusts close to 20 kt by sunset. The better chance for these gusts will first start across the northern NJ ocean waters. Winds turn west this evening and become west-northwest overnight while still increasing.

A Small Craft Advisory has been issued for all ocean waters including the Delaware Bay for tonight as wind gusts start to reach 25-30 kt.

Outlook...

Tuesday and Wednesday...Small Craft Advisory conditions likely with Gale force winds possible. A Small Craft Advisory remains in place for all coastal waters Tuesday. A Gale Watch remains in place for Tuesday night for Atlantic Ocean coastal waters south of Little Egg Inlet as well as the Delaware Bay.

Wednesday night through Friday...Lingering SCA conditions possible on Wednesday night, otherwise no marine headlines are expected.

PHI WATCHES/WARNINGS/ADVISORIES

PA...None. NJ...None. DE...None. MD...None. MARINE...Small Craft Advisory from 1 AM to 6 PM EST Tuesday for ANZ430- 431-454-455. Gale Watch from Tuesday evening through late Tuesday night for ANZ430-431-452>455. Small Craft Advisory from 7 PM this evening to 6 PM EST Tuesday for ANZ450-451. Small Craft Advisory from 10 PM this evening to 6 PM EST Tuesday for ANZ452-453.