textproduct: State College

WHAT HAS CHANGED

* Sat night and Sunday look like they will turn out mostly dry as models continue to push the the main batch of showers and storms out quicker.

KEY MESSAGES

1) Showers likely and a thunderstorm possible Friday (west).

2) Rain area-wide Fri night-Sat night does not look heavy. Sunday now looking dry.

3) Several more shots at rain follow for the new week.

DISCUSSION

KEY MESSAGE 1: Showers likely and a thunderstorm possible Friday (west).

Warm front lifting northward through the western and southern counties on Friday will help to generate scattered SHRA/TSRA, mainly in the afternoon, but one or two could form in the early morning. Most models produce convection, and confidence is high. Clearfield county seems like it would be the most-likely place to get 2 or more SHRAs. PWAT barely gets near 1" by the end of the day. Best instability will be around there. Point amounts may near 0.25", but chc for more than that is very low. Light easterly wind to the east of the warm front could keep the temps there down 4-7F vs Thurs.

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KEY MESSAGE 2: Rain area-wide Fri night-Sat night does not look heavy. Sunday now looking dry.

MCS looks likely to drop down from the Upper Great Lakes Friday night, but the 8H jet looks weak. Timing looks more-solid, now, with the bulk of the rain in the second half of Fri night and early Sat. Some models/members linger precip much of Sat with the big upper low over nrn New England retrograding/wobbling westward slightly. Energy dropping southeast could still provide enough lift to trigger sct SHRA/TSRA Sat - mainly in the east.

There could be a little briefly heavy rain from TSRA, but the overall QPF for Fri night into Sat night is 1" or less. Everything is grown across the southern 2/3rds of the CWA. Even the N is seeing a little color on the hills. Therefore, there is no threat for flooding. Overall, Sat looks 10F cooler than Fri on the whole, with the E cooler (50s) vs W (60s).

Upper ridging builds in on Sun with a drying trend continuing amongst the preponderance of solutions. Lag is about the only thing keeping a 20 PoP in for Sun for now. Overall, it looks like the sky will brighten Sun with maxes in the 60s.

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KEY MESSAGE 3: Several more shots at rain follow for the new week.

Upper low to our NE finally slides east and allows a brief visit from dry weather later Sun-Mon. The upper ridge is weak and breaks down quickly, though and moisture from the west rolls in Mon night/Tues. The pattern looks favorable for at least two shots of rain with two cold fronts mid-week. Timing and details are uncertain, though. Neither front looks like a significant transition, and temps stay seasonable. Many places in Central PA would welcome additional rainfall, esp the S.

AVIATION /09Z THURSDAY THROUGH MONDAY/

VFR conditions prevail tonight and should be the primary condition across the area through the end of the TAF period. Overnight (after 06Z), fog development becomes a concern due to largely cloud-free skies and light winds, particularly across the southeastern airfields (KMDT/KLNS) and near KBFD.

For KMDT/KLNS, light easterly flow on the backside of the low pressure that brought us rain showers earlier today will keep low-level moisture in place, increasing the chances for visibility restrictions due to mist/fog. Confidence for fog (around 30%) is higher at KLNS given their proximity to the coast, with less confidence at KMDT.

In addition to fog potential at the aforementioned airfields, upslope winds at KJST may contribute to low clouds developing after 06Z, with restrictions to IFR favored (60% chance) at the site. Any restrictions will improve by mid morning with light winds and mostly sunny skies expected areawide.

Outlook...

Fri...Light rain possible. VFR to MVFR.

Sat-Sun..Periods of rain with MVFR to IFR conditions.

Mon...Mainly VFR, decreasing ceilings later in the day.

CTP WATCHES/WARNINGS/ADVISORIES

None.