Marine Weather and Tide Forecast for Washington Boro, PA

NEAR TERM /THROUGH TONIGHT/
Nighttime cloud microphysics and regional MRMS loop radar loop at 03Z shows widespread clouds over much of the CWA with still SCT-BKN sky cover across portions of our far east zones.

Weak mid and upper level troughing over and just to the west of PA early today combined with shallow moisture ascending the Western Mtns (and the entire layer of cloud cover falling within the DGZ) will continue to generate periods of light snow near and to the west of the RT 219 corridor today and tonight.

Variable amounts of strato cu with flurries will be found further east across the Ridge and Valley Region of the state.

Snow accums today and tonight will likely be in the 1-2 inch range across the region west of RT 219 with the ridge tops and west facing slopes having the best chance to see these amounts.

Clear skies earlier in the overnight and a calm wind allowed locations near and to the East of the Susquehanna Mainstem to fall into the single digits. These locations have recently jumped back int the 10-15F range as cloud cover moved in from the west and a light breeze developed with the approach of a weak cold front.

Temps elsewhere to start the day will be in the upper teens to low 20s.

Weak llvl cold advection will keep temps across the west nearly steady today, while locations throughout the Central Mountains and Susq Valley will see the mercury rise several, to as much as 20 deg F respectively from their daybreak values. This will equate to afternoon highs in the mid to upper 20s.

SHORT TERM /SATURDAY THROUGH SUNDAY/
Any snow showers should end late tonight/early Saturday Friday night, as surface ridging builds into the state and boundary layer flow shifts to the southwest.

Light winds under the surface ridge (across the east), combined with snow cover and breaking stratocu (over the Central and Wrn Mtns), should result in a cold min temps in the single digits throughout the entire CWA

WAA ahead of the next northern stream system should bring an increase in cloud cover Saturday with some very light snow even possible over the NW Mtns during the afternoon. Another moisture starved cold front is fcst to traverse CPA Saturday night->early Sunday with ensuing CAA expected to drive another period of lake effect upslope snow showers over the western and northern mtns (minor to light accums).

Reinforcing shot of cold air will result in a neutral to negative rate of change in max temps on Friday with highs 10 to 20 degrees below climo. A gradual moderation (thawing?) is then projected through the weekend.

LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/
Medium range guidance supports mainly dry and seasonably cold weather early next week, as upper level troughing remains over the region. One notable shortwave is progged to drop south across the region Tuesday, reinforcing the cold air. Decent moisture return in the pwats fields suggest a round of snow showers is likely to accompany the associated cold front Tuesday. Instability fields in some model guidance even suggests heavier squalls are possible across the N Mtns.

A cold northwest flow behind the front is likely to produce lake effect snow showers Tue PM across the W Mtns. However, low inversion heights and a frozen Lk Erie should result in minimal accumulations. A second, weaker shortwave may track north of PA Wed, preceded by a bit of very light WAA snow over the N Mtns and followed by a resumption of light lake effect snow showers across the W Mtns Wed PM into Thursday.

Although below normal temperatures appear likely Wed and Thu of next week, the latest EPS 2m temp plumes show a large spread, ranging from slightly above average, to around 20 degrees below average. This uncertainty is reflective of PA being within a tight gradient in 850mb temps on the southern periphery of the core of coldest air, which is progged to pass from Southern Ontario into New England.

AVIATION /09Z FRIDAY THROUGH TUESDAY/
The bulk of model guidance is in agreement that VFR conditions will prevail at all airfields outside of BFD/JST with high confidence (~80-90%) through 0Z Saturday, with the main concern at AOO/UNV/IPT/MDT/LNS being breezy sustained winds near 5-10kts at 250-300, with gusts up to 20kts after 12Z Friday.

At BFD/JST, lake effect and orographically enhanced snow showers will bring about MVFR visibilities with borderline IFR/MVFR ceilings, mainly situated later this evening (22Z to 04Z Friday) and after sunrise on Friday (12Z to 18Z Friday). A combination of HRRR/RAP model guidance does suggest the potential for period where snow showers do not impact these airfields; however, given some residual moisture, have left mentions of VCSH in the TAFs throughout this timeframe with moderate (40-50%) confidence. Any alternative solution at BFD/JST will mainly entail less snow coverage, which could allow for a longer duration of MVFR conditions with IFR conditions less likely; however, this is a lower confidence (~30%) solution at this time. Overall ceiling improvements are not likely at BFD/JST until after 06Z Saturday.

Outlook...

Sat...VFR/No Sig Wx.

Sun-Tue.. MVFR possible in -SHSN across Northern & Western PA.

CLIMATE
A record low temperature of -11 degrees was set at Altoona, PA early Wednesday morning. The old record was -5 degrees set in 1984.

A record low temperature of -11 degrees was also set at Johnstown, PA early Wednesday morning. The old record was -9 degrees set in 1984.

A record low temperature of -18 degrees was tied at Bradford, PA early Wednesday morning. The previous record low temperature date was 2022.

CTP WATCHES/WARNINGS/ADVISORIES
None.