textproduct: State College

WHAT HAS CHANGED

* Little change in the coating to ~1 inch snowfall amounts expected for late tonight/early Sunday across mainly the higher terrain across the northern half of PA.

KEY MESSAGES

1) Mild end to February/meteorological winter 2025-2026.

2) Light rain and snow tonight/Sunday morning.

3) Wintry mix likely Tuesday followed by periods of rain with temperatures trending above average for early March.

DISCUSSION

KEY MESSAGE 1: Mild end to February/meteorological winter 2025-2026

Another mostly sunny and mild afternoon today to close out the month of feb, with high temperatures this afternoon expected to range from the mid/upper 40s across the NW Mtns to low 60s throughout the central and southern valleys of PA.

Moisture-starved cold front is pushing into the Mid Susq Valley and Scent PA as of 19Z, and deeper/colder air is lagging this sfc boundary by several hours.

KEY MESSAGE 2: Light rain and snow tonight/Sunday morning.

A weak wave of low pressure (linked to a period of meso-B scale UVVEL beneath the right entrance region of an upper level jet max) is expected to develop tonight along a stalled frontal boundary to our south. These weather features will combine to bring light precipitation to Central PA later tonight into Sunday morning.

Accumulating snow will largely be confined to areas north of I-80 (and focused at elevations AOA 1500 ft MSL), where anywhere from a coating to 1.5 inches is likely.

Model soundings suggest that areas farther to the south may struggle to see saturation reach into the dendritic growth zone (that will be located around the top of the cloudy layer - near and above 10 KFT AGL), potentially leading to light rain or some light sleet showers/freezing drizzle being the predominant weather types. A light glaze of ice appears possible for areas south of I-80 and north of the turnpike, though the very mild ground temps this afternoon doesn't provide a good setup for that.

KEY MESSAGE 3: Wintry mix likely Tuesday followed by periods of rain with temperatures trending above average for early March

March comes in more like a lion vs. lamb, but just a short wintry roar before springlike conditions take over.

Modified arctic high migrating southeast from the Great Lakes now provides a chilly and dry day on Monday. This setup favors CAD/overrunning wintry mix scenario for Tuesday as moisture spreads north/east into retreating cold sector. Despite its magnitude 1040mb, the high appears somewhat transient which suggests a progressive wintry mix to rain ptype transition from SW to NE by later Tuesday into Tuesday night.

Timing will likely shift around, but the main themes from next Wednesday through the first weekend of March will be increasingly mild with periods of rain. A sizable and springlike warming trend appears to have staying power based on the 6-10/8-14 day CPC temp outlooks.

AVIATION /19Z SATURDAY THROUGH THURSDAY/

Widespread VFR for the rest of today and early tonight at all TAF sites, except for possibly KBFD where a shallow stratus deck may develop/advect SE after 21Z Sat.

Across the Susq Valley, a fairly light south/southwest breeze still exists but will be veering to the west then NW during the mid to late afternoon as a dry cold front pushes through. A moderate west- northwest breeze, gusting into the 20 to 25 mph range will add a bit of chop to takeoff and FAP, especially at Central and Western PA airfields.

The next surge of moisture arrives in the second half of tonight as a low pressure area forms just to our south, moving eastward.

A light northerly wind flow and initially clear/partly cloudy skies will allow temps to dip into the 20s N or I-80, and perhaps as low as the upper teens at BFD. The increasing moisture could produce IFR cig/visby later Sat night, mainly at JST and BFD (50%) with lesser chances (30-40%) for IFR at MDT/LNS and even lower (20-30%) for UNV/AOO/IPT. LIFR is possible (30%) at BFD when snowing. Light snow accums are expected N of I-80, and the chilly low stratus deck elsewhere may also lead to some de-icing being necessary.

Precip slides east and tapers off thru the morning on Sun. By 18Z, only flurries (NW third) or drizzle (MDT/LNS) will be left, and it will continue to dry out on freshening NW wind.

Outlook...

Mon...VFR likely.

Tue...Restrictions likely in wintry mix changing to rain.

Wed...Restrictions possible in periods of rain.

CTP WATCHES/WARNINGS/ADVISORIES

None.