Marine Weather and Tide Forecast for Chambersburg, PA

NEAR TERM /THROUGH TODAY/
Early this evening a tight instability gradient is present near the PA/MD line. So far a narrow corridor of enhanced shear and instability has led to thunderstorm development just to the south of the area. The lack of instability has resulted in a hostile environment for any thunderstorms further north but did increase the pops across south central Pennsylvania to account for the ongoing showers. Temperatures were also lowered a few degrees in this area as well.

SHORT TERM /TONIGHT THROUGH 6 PM SUNDAY/
Episodic showers and storms continue through Saturday with the primary hazard being localized heavy downpours. WPC keeps most of CPA in the MRGL ERO for D3/Saturday. It won't be raining the entire time/not a washout -- but most locations will see some rain showers. Increased cloud cover along with humidity points toward lower daytime highs (70s) and higher nighttime lows (60s).

LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/
Overall tone/message of the long term has not changed with this late evening update = high PoPs (relatively for the long range).
While confidence in timing of the stronger waves is low, confidence is high that we'll get wet many of these days. WPC ERO places PA in the MRGL category for Days 3,4,& 5 (Sat-Mon).

Prev...
Unsettled weather pattern continues into next week with ample opportunities for rain. A series of shortwave impulses rippling west to east into a high PW corridor within a quasi zonal or "troughy" 500mb configuration from Midwest into the Mid Atlantic/Northeast will continue to bring periods of rain showers and locally heavy downpours. WPC ERO for Sunday (D4)
includes all of CPA while shifting the southern tier on Monday (D5).

Sunday/Monday look like the coolest days with CAD signature established to the north of sfc wave tracking through the Delmarva. Temps rebound by midweek as flow shifts back to the west/southwest.

AVIATION /06Z SATURDAY THROUGH WEDNESDAY/

Ceilings are beginning to lower with rain showers moving in from the west. Current MVFR conditions at the majority of terminals will worsen to IFR within the next few hours, with conditions likely staying IFR through the TAF period, or bouncing conditions between MVFR and IFR.

Outlook...

Saturday through Wednesday...Daily chances for showers and thunderstorms, especially during the late afternoon and early evening hours.

CTP WATCHES/WARNINGS/ADVISORIES
None.