textproduct: State College

SYNOPSIS

A quick moving system will bring rain to the area tonight, along with some elevation-driven wet snow. Mainly dry weather returns for Wednesday and Thursday before another system may bring some rain showers to the area Friday into Saturday. A return to mainly dry weather arrives for the second half of the weekend.

NEAR TERM /UNTIL 7 AM THIS MORNING/

short wave trough moving through OH and into wrn PA now. The precip is on time. Sleet being reported at quite a few places locally. All light stuff, though. HRRR progs precip to be out to the east by mid-morning...perhaps a little slower than going fcst. The visby and cigs have not come down to the ridges quite yet. But, we do anticipate a significant lowering to the clouds and some drizzle/fzdz may form later tonight. Mentions of fog and mixed precip are in the grids, and feel comfortable with those mentions.

Prev... A fast moving low pressure system will move through the area later today through tonight. Some warm air advection precipitation ahead of this system has moved into parts of the Commonwealth, but with dry air in place, much of this has been virga or simply just very light precipitation. At some of the higher elevations, temperatures are just cold enough at the onset to start as some light snow, but any accumulations will be minimal due to marginal temperatures and the light intensity of the snow.

Tonight will be somewhat of a tricky forecast due to potential wet bulbing allowing for temperatures to be a few degrees cooler wherever there is steadier precipitation. This could allow for rain to transition back to snow during the steadier precipitation, especially at the higher elevations over east- central PA near/along the I80 to US220 corridors in the 06-12Z window. Snow accum is most likely on non-paved and elevated surfaces with minimum temps hovering near to slightly above the freezing mark. Precipitation should end/shift to the east by 7AM/12Z Wednesday.

SHORT TERM /7 AM THIS MORNING THROUGH THURSDAY NIGHT/

High pressure will bring mainly dry weather to the area for Wednesday and Thursday, but lingering low level moisture will likely keep clouds in place for most of the Commonwealth. Clouds will be present area-wide on Thursday, but Wednesday may actually have some sunshine for areas north of I-80. Seasonable temperatures are expected with highs in the mid 40s to lower 50s

LONG TERM /FRIDAY THROUGH TUESDAY/

Another system will slide eastward from the Ohio Valley Friday into Saturday, but there is a bit of uncertainty regarding how far north the precipitation gets. Some guidance, such as the 12Z ECMWF keeps most of the precipitation south of the Commonwealth, while other guidance, such as the 12Z GFS, as the axis of steadier precipitation moving right through PA. The NBM captures this uncertainty relatively well with chance PoPs across most of the area. After this system moves through, drier weather arrives for the second half of the weekend into early next week.

AVIATION /07Z WEDNESDAY THROUGH SUNDAY/

Weak surface low pressure near KDCA with an inverted trough extending north into Central PA was being supported by a potent albeit compact upper level short wave moving across SW/Scent PA at 07Z.

Wet Bulb Zero C temps are under 1000 ft AGL across the Bulk of Central PA (with the exception of far southern PA, the Laurel Highlands and West Central Mtns. Significant bright banding shows large water-coated snowflakes making it to the ground now at KUNV and we expect the precip type to be mainly snow between 08-11Z (after about an hour of initial light rain 07-08Z) at KIPT, KAOO and KSEG.

Conditions during this 2-3 hour burst of MDT intensity precip will be mainly IFR to low-end MVFR Vsbys and IFR CIGS.

Precip Type at KMDT and KLNS should be mainly rain with a little wet snow possibly mixed in between 09-12Z today.

After the rain/snow moves out of the area between 12-13Z today there will still likely be some IFR ceiling restrictions around through most of the late morning. Some gradual improvement is expected by late Wednesday morning/early afternoon.

Outlook...

Wednesday afternoon through Thursday...Partial improvement in conditions, but some lingering restrictions possible due to lower clouds.

Friday through Saturday...Rain and associated restrictions likely.

Sunday...Mainly VFR.

CTP WATCHES/WARNINGS/ADVISORIES

None.