textproduct: State College

WHAT HAS CHANGED

* Forecast rolling along nicely.

KEY MESSAGES

1) Mainly dry, tranquil and cooler weather pattern expected into the last weekend of July.

DISCUSSION

KEY MESSAGE 1: Mainly dry, tranquil and cooler weather pattern expected into the last weekend of July.

Sky is clearing nicely now after a bit of a struggle to get rid of the thick blanket of cu across the north. Slightly higher elev clouds over the SE are also headed out to the east as the upper trough axis slowly shifts overhead. Fog still looks probable in the deep river valleys of the N.

Previous...

High pressure continues to build in with a refreshingly dry airmass on the way. Evening stratocumulus and cumulus will fall apart/erode after sunset giving way to mainly clear skies overnight. With dewpoints dropping into the 40s and 50s tonight, clear skies and calm winds will allow temperatures to plummet to well below normal for this time of year. Low temperatures by Thursday morning will range from near 40 in the northwest to the mid 50s in the SE. With river temperatures much warmer than the incoming airmass, radiational cooling will support areas of valley fog late tonight into early Thursday morning, especially in the deepest valleys of northwest Pennsylvania.

High pressure will gradually drift across Pennsylvania over the next few days, ensuring a sustained period of cooler than average and dry/less-humid weather. The center of high pressure will pass east of Pennsylvania later this week, resulting in winds shifting around to come out of the south. As such, temperatures and humidity will begin to increase once again. An upper trough carving out over the eastern Great Lakes into the Northeast US will bring rain chances back into the forecast Sunday into next week. At this time, no significant systems are anticipated, but long range outlooks favor temperatures remaining near or below average through the end of July.

AVIATION /02Z THURSDAY THROUGH MONDAY/

High pressure over the central states will slowly build eastward into Pennsylvania over the next few days. Stratocumulus and cumulus clouds should erode away overnight as drier air continues to move in. Tapering winds and clearing skies will support fog in the deepest valleys across northern PA by Thursday morning. No impacts are expected at area airfields, but the current TAF package includes a mention of vicinity fog at KBFD as that location has the relatively highest chance of impacts.

VFR conditions should prevail into at least the first part of Saturday, before the chances of showers and storms increase later in the weekend. Each day will be marked by dry conditions and generally tranquil weather - ideal for flying.

Outlook...

Fri...Some potential for valley fog across NW PA Friday morning; otherwise, VFR conditions expected.

Sat...Generally VFR conditions with low-end (< 20%) chance of an afternoon shower/storm across western sections of central PA.

Sun...Increasing chances of PM showers/storms, with some restrictions possible.

Mon...Still a chance showers and storms.

CTP WATCHES/WARNINGS/ADVISORIES

None.