textproduct: Philadelphia/Mt Holly

WHAT HAS CHANGED

A Small Craft Advisory has been issued for all NJ and DE Atlantic coastal waters for Saturday into Saturday evening.

KEY MESSAGES

1. An unsettled pattern will lead to a few chances for showers and thunderstorms this weekend into early next week.

DISCUSSION

KEY MESSAGE 1...An unsettled pattern will lead to a few chances for showers and thunderstorms this weekend into early next week.

Temperatures look to remain seasonable through Saturday with highs in the upper 60s to low 70s and lows in the mid 40s to low 50s for most.

An unsettled pattern looks to take shape across the region beginning on Saturday as mid-level troughing begins to take shape across much of the Northeast and Mid-Atlantic. A mid-level shortwave will pass through the region some time on Saturday. An attendant surface trough will pass through the area, leading to scattered or even widespread shower development late Saturday morning into Saturday afternoon. Saturday afternoon, shower coverage will likely become a bit more sparse, but some guidance depicts additional scattered shower development across portions of southeastern PA, southern NJ, and the Delmarva through the evening. It is unclear to what extent clearing and destabilization will occur, but it still appears that enough instability may be realized for a few thunderstorms. The severe weather potential appears low at this time. Overall rainfall amounts look to be generally on the order of 0.1-0.25", though higher amounts could occur with any thunderstorms.

After the passage of the shortwave on Saturday, height rises aloft and a brief period of high pressure at the surface will allow for dry conditions most of the day Sunday as well as for substantial warming to take place with return flow ahead of the next system approaching from the west. High temperatures on Sunday look to be in the mid 70s northwest of I-95, and upper 70s to near 80 southeast.

Another wave of low pressure and an accompanying cold front look to move through the region Sunday night into Monday morning, bringing with it another chance for showers and perhaps a few thunderstorms. After the passage of the cold front, temperatures look to return to slightly below normal through the first half of the next work week.

AVIATION /06Z FRIDAY THROUGH TUESDAY/

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

Overnight...VFR. SCT/BKN clouds thru 06-08Z, decreasing thereafter. Winds NW around 5 to 10 knots. High confidence.

Friday... VFR. SKC in the morning, giving way to SCT/BKN clouds in the afternoon. West winds increase to around 10-15 kt with gusts up to 20-25 kt possible. High confidence.

Friday night...Becoming mostly cloudy but remaining VFR. Winds light and variable early settling out of the S/SE around 5 knots or less overnight.

Outlook...

Saturday...Sub-VFR conditions expected at times in periods of showers and perhaps a few thunderstorms.

Saturday night...Primarily VFR. Some low clouds or patchy fog are possible.

Sunday...VFR. No significant weather.

Sunday night through Monday...Sub-VFR conditions expected at times in periods of showers and perhaps a few thunderstorms.

Monday night through Tuesday...VFR. No significant weather.

MARINE

Weak high pressure will ridge up across the waters into Friday. Not much eventful weather expected as winds will be rather light overnight and then occasionally gust around 15-20 kt early Friday morning. On Friday, the high slides east and winds will back around to southwest and increase to 10 to 15 kt. Seas on the ocean will be 2 to 3 ft. Fair weather. No marine headlines expected through Friday night.

Outlook...

Saturday through Saturday night...A Small Craft Advisory has been issued for Saturday morning through Saturday evening. South wind 15- 20 kt and gusts around 25 kt and seas 3-6 feet expected. Winds and seas look to diminish late Saturday evening below SCA criteria. Widespread showers are expected and a few thunderstorms are possible.

Sunday through Tuesday...No marine headlines currently anticipated with winds under 25 kt and seas under 5 feet. Widespread showers are expected and a few thunderstorms are possible Sunday night into Monday.

PHI WATCHES/WARNINGS/ADVISORIES

PA...None. NJ...None. DE...None. MD...None. MARINE...Small Craft Advisory from 10 AM Saturday to midnight EDT Saturday night for ANZ450>455.