textproduct: State College

WHAT HAS CHANGED

*Lowered dewpoints and minimum RH this afternoon. *WPC added a level 1/4 excessive rain risk for Monday 7/27.

KEY MESSAGES

1) Pleasant/dry pattern continues into the last weekend of July. 2) Turning more humid with showers and storms next week. Perhaps a few strong storms with heavy rain at times.

DISCUSSION

KEY MESSAGE 1: Pleasant/dry pattern continues into the last weekend of July.

After a stormy period since last weekend, a really nice afternoon outside with clear skie and low humidity levels. PW values about as low as they get this time of year.

High pressure over the region will provide the area with another night with clear skies and cool temperatures.

Friday will feature another day of sunshine and low humidity.

While there could be a shower or storm over the region this weekend, the airmass remains rather dry. Main support for any activity would be across western sections on Sunday.

KEY MESSAGE 2: Turning more humid with showers and storms next week. Perhaps a few strong storms with heavy rain at times.

Weak systems dropping southeast next week will bring chances for showers and storms at times. Systems are rather weak and will be moving along, so timing would be a factor.

The other factor is that the higher dewpoint air is expected to be rather limited, mainly later on Tuesday.

Main timing for anything widespread would be late Monday night into early Wednesday.

More detail below.

The pattern looks increasingly unsettled Sunday into the middle of next week as upper troughing is carved out over the Great Lakes/Ohio Valley into the Mid-Atlantic and Northeast states.

Ample northern stream system energies set to dig into the upper trough position will support potential for strong storms and heavy rainfall. WPC introduced a broad level 1/4 marginal excessive rain risk for D5/Monday July 27 that covers most of CPA.

Severe storm potential could shift east/southeast on Tuesday. Confidence in where greater risk corridors may develop is low, and will largely be influenced by convective evolution in the Days 4-5/Sunday-Monday periods.

AVIATION /18Z THURSDAY THROUGH TUESDAY/

High pressure building over the area will provide clear skies to the area into at least Friday.

Not a lot of potential for fog tonight, fcst temperatures fcst to drop to near dewpoints, but dewpoints are fcst to fall too, so not really much chance of reaching the cross over temperature for fog formation at our 7 TAF sites. The airmass about as dry as it gets in July.

Winds will be rather light into Friday.

Outlook...

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.

Tue...More in the way of widespread showers and storms.

CTP WATCHES/WARNINGS/ADVISORIES

None.