textproduct: State College

WHAT HAS CHANGED

* Level 2/5 severe t-storm risk for Thursday afternoon expanded southward across the Lower Susquehanna Valley * Excessive rainfall risk for Thursday afternoon upgraded to level 2/4 for areas near and to the east of US-15/I-81

KEY MESSAGES

1) Scattered strong to severe thunderstorms possible Thursday PM

DISCUSSION

Valley fog, some locally dense, will reduce visibility early this morning across CPA. Fog will gradually dissipate by 9-10AM.

KEY MESSAGE 1: Scattered strong to severe thunderstorms possible Thursday PM

Scattered thunderstorm development is expected Thursday afternoon ahead of a cold front across CPA. SPC expanded the level 2/5 severe t-storm risk southward to include the Lower Susquehanna Valley. WPC upgraded the ERO to level 2/4 for areas near and to the east of US-15. Short term model guidance continues to highlight the eastern 1/3 of CPA with the most favorable CAPE/shear profiles and highest pwats/slowest storm motions. A predominantly multicellular storm mode is expected with damaging winds the primary threat, however a few supercells may also be possible. Higher FFGs could offset the flash flood risk in the eastern zones to some extent, with the most saturated soils and lowest FFG over the southwest quadrant of the CWA.

-------------------------------------------------------------

Forecast viewing conditions for the lunar eclipse range from fair to poor Thursday night across central PA. The eclipse will begin at 10:34 pm EDT and last for about 3 hours, ending at 1:52 am EDT Friday. The worst view is most likely over the eastern half of CPA due to exiting storms and associated cloud cover. The eclipse will take place during August's full moon, commonly referred to as the Sturgeon Moon. It will also be the last full moon of the summer with the next full moon set to rise a few nights after the autumnal (Fall) equinox on September 22nd.

A drying trend is forecast Friday through the last weekend of August, thanks to high pressure building into the area behind the cold front. This will likely setup a couple of foggy mornings. Rainfall looks fairly limited heading into the first week of September; however despite the start of meteorological Fall the summer is not over with temps expected to rise above the historical average into the 80-90 degree range.

AVIATION /07Z WEDNESDAY THROUGH SUNDAY/

Mainly clear skies and light winds will allow for patchy valley fog to form tonight over north-central PA. IFR restrictions appear most likely at BFD, IPT, and UNV. AOO may also see impacts from fog. 00Z HREF has bump in LIFR ceiling probabilities at LNS between 10Z-14Z but no other guidance seems to support this solution so confidence in its occurrence is low (<20%), but will amend if necessary. VFR conditions will return regionwide by 14Z and will continue through the rest of the day under partly cloudy skies. Winds will be out of the south at 5 to 10 knots. VFR continues into the overnight.

Outlook...

Thu...Restrictions possible in scattered afternoon showers and storms. Strongest storms look to be in Eastern PA.

Fri...Still a slight chance of a shower, VFR otherwise.

Sat-Sun...Clearing conditions, VFR favored.

CTP WATCHES/WARNINGS/ADVISORIES

None.