Marine Weather and Tide Forecast for Ingram, PA

KEY MESSAGES
1) Hazardous cold continues into Monday morning. Cold Weather Advisory issued for portions of northwest and western PA.

2) Warmer temperatures and chances for light rain/snow Tuesday.
Wednesday through late week continue to trend colder than seasonal normals.

DISCUSSION
KEY MESSAGE 1...
Height rises and surface high pressure centered over NW PA foster clearing skies and calm winds tonight into Monday morning. These conditions should result in efficient radiative cooling and nocturnal decoupling, allowing temperatures to drop to near or below -15F in portions of western PA mainly north of Pittsburgh. A Cold Weather Advisory has been issued, and will run from 10PM this evening until 10AM Monday. For areas farther south and west, scattered cloud cover associated with an upper disturbance crossing the lower Ohio Valley will mitigate cooling and keep temperatures generally above Advisory criteria, though can't rule out some brief and localized instances of temps dropping to near -10F during breaks between clouds.

KEY MESSAGE 2...
Prior messaging on the areawide "warm up" remains on track through Tuesday thanks to the development and passage of a shortwave ridge as well as surface low movement Tuesday well north of the area fostering surface warm advection. Confidence remains high on most locations seeing temperatures reach and exceed the daily average by Tuesday; the main uncertainty is the potential timing of a surface cold front as well as quickness in returning cloud cover that act to limit/end warming processes.

There is still medium to high confidence that precipitation will be observed Tuesday into Tuesday night with the passage of the cold front, especially for western PA and northern WV. However, there also remains medium to high confidence that accumulations will be very light, which is captured by the fact that NBM probabilities of exceeding 0.01" during any particular 6-hr window from Tuesday afternoon to Wednesday afternoon are only around 10-20%. Even the probability of exceeding 0.01" over that entire 24-hr period is only 25-45%. Thus, the most likely scenario still appears to be areas of light rain/snow or drizzle/flurries associated with the frontal passage (ptype depending on frontal passage timing and local thermal profiles).

Meanwhile, the signal in guidance from late last week that pointed to a warmup continuing beyond Tuesday has all but vanished into cold, thin air. This is because more ensemble members have latched on to a solution that favors an eastern CONUS trough remaining in place, rather than shifting it to our east like previous guidance had done. Persistent troughing would instead support below-seasonal temperatures Wednesday through the end of the week, with highs each day right around freezing and lows dropping into the 20s and teens (possibly single digits along I-80 Thursday/Friday nights).

AVIATION /00Z MONDAY THROUGH FRIDAY/
KEY MESSAGES...

1) VFR with light winds.

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Strong confidence for VFR area-wide with light winds. By the afternoon, high clouds will encroach on the area. Light easterly wind tomorrow will veer out of the southeast by the evening.

Outlook...
High pressure and subsidence will favor VFR through Tuesday morning. Chances of MVFR cig restrictions increase late Tuesday into Wednesday.

PBZ WATCHES/WARNINGS/ADVISORIES
PA...Cold Weather Advisory until 10 AM EST Monday for PAZ007>009- 013>016-020>022-073-074-077-078.
OH...None.
WV...None.