Aviation Forecasts Discussions (AFD) INFO

(EXTRACTED FROM FXUS61 KPHI 212040)


    The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG,
    KMIV, KACY and surrounding areas.
    
    Rest of this afternoon...VFR ceilings, with localized MVFR ceilings
    at times (cloud bases between 2,500-5,000 feet). Southwesterly winds
    around 5 knots.
    
    Tonight...VFR (marginal MVFR) ceilings lower to MVFR, then to near
    IFR overnight. The lowest ceilings are anticipated for RDG, ABE and
    TTN where especially some light rain, drizzle and fog will also be
    possible. Low confidence however regarding the ceilings. Southerly
    winds less than 5 knots or light and variable.
    
    Monday...Sub-VFR conditions improve to VFR from south to north
    through early afternoon. Some light rain, drizzle and/or fog is
    possible in the morning, especially north and west of PHL. Lower
    confidence regarding the ceilings. Light and variable to southerly
    winds less than 10 knots.
    
    Outlook...
    
    Monday night...conditions lowering to IFR or less with low ceilings
    and visibility restrictions due to rain. Southerly winds of 10 to 15
    kt are expected. A period of low level wind shear (LLWS) is likely
    to develop late Monday night as a strong low level southerly jet
    develops, though exact timing and location of the jet is uncertain
    for now.
    
    Tuesday...Starting IFR or lower Tuesday morning, but improving to
    VFR conditions behind a cold front expected during the day Tuesday.
    Also expect an abrupt wind shift from southerly to westerly winds
    with the cold front. Wind speeds of 10 to 20 kt with higher gusts
    will be possible especially just behind the cold front. LLWS
    conditions may linger into Tuesday morning along the coastal plains.
    Timing of the front, and consequently improving conditions is
    uncertain at this time.
    
    Tuesday night through Friday...VFR conditions expected. Westerly or
    northwesterly winds less than 15 kt. Gusts above 20 kt possible
    during the day Wednesday and Thursday. High confidence.