textproduct: State College

WHAT HAS CHANGED

* No significant changes

KEY MESSAGES

1) Unseasonably mild through Friday with 2-week dry spell coming to an end

2) Trending cooler this weekend with showers downwind of Lake Erie

DISCUSSION

KEY MESSAGE 1: Unseasonably mild through Friday with 2-week dry spell coming to an end

Anomalous upper level ridging and south-southwest flow aloft will maintain unseasonably warm temperatures through late week. Max/Min temps will be 10 to 20 degrees above the historical average for the first week of November, but should fall short of daily records.

A vertically stacked and weakening surface low pressure system will send a front through our area Wednesday night into Thursday morning. A band of rain showers will accompany this surface feature with accumulations looking to remain under half an inch. This cold frontal feature looks to stall near the coast Thursday as it becomes more strung out.

An approaching shortwave through though will likely reinvigorate precipitation development along the frontal system. The main area of uncertainty is if this new area of precipitation will impact much of our area. Global models have trended towards keeping the bulk of this precipitation closer to the coast, but some showers may still nudge into our southeastern area Thursday night into Friday.

KEY MESSAGE 2: Trending cooler this weekend with some showers downwind of Lake Erie

A compact shortwave moving through from the Great Lakes will induce a pattern of cooler cyclonic WNW flow pattern this weekend. This favors a pattern of lake effect showers off of Lake Erie moving southeastward and cooler overall temperatures. Latest model data favors this activity mostly on Saturday.

AVIATION /18Z TUESDAY THROUGH SUNDAY/

Mainly clear skies in the south today with a few lingering low clouds across the northern tier of PA will keep flight conditions VFR into this evening. A few areas of low ceilings and fog could develop tonight over the eastern terminals of IPT, MDT, and LNS. Latest GFS LAMP guidance does not depict any degradation of flight conditions, but REFS ensemble guidance is showing more confidence (~60%) in MVFR to IFR conditions after 09Z. Any fog and clouds that do develop should lift shortly after sunrise with most of Wednesday experiencing VFR after 14Z.

The next chance for impactful precipitation will arrive Wednesday evening (NW) and overnight into Thursday across the Central and Eastern part of the CWA. Low pressure will track NE from the Central Plains and reach the Upper Great Lakes Wednesday evening. Strengthening southerly flow ahead of the low's southward trailing cold front will create a moderately gusty southerly flow over the western half of PA Wednesday and Wed night with a 12-15 hour period of LLWS later Wednesday into the mid morning hours Tuesday.

Outlook...

Wed-Thu...Rain showers, especially in the PM hours on Wednesday and continuing into Thursday. Sub-VFR conditions become more likely in showers.

Fri-Sat...Scattered to isolated rain, cloudy conditions and sub VFR ceilings possible.

Sun...Mainly VFR, isolated rain in NW PA.

CLIMATE

Current Consecutive Days streak without measurable rain:

10/17 through 11/2 (17 days) Harrisburg, Williamsport, Altoona, State College

10/18 through 11/2 (16 days) Bradford, Johnstown

CTP WATCHES/WARNINGS/ADVISORIES

None.