textproduct: State College

WHAT HAS CHANGED

* Posted dense fog advisory for Laurels. May need to go into the east if clearing develops (50/50 chance). * Made mentions of snow with system next weekend.

KEY MESSAGES

1) Coating of snow for the east, coating of fog for the west and maybe east, too.

2) Mid-February thaw still on tap.

3) Late-Feburary cold snap taking shape.

DISCUSSION

KEY MESSAGE 1: Coating of snow for the east, coating of fog for the west and maybe east, too.

Overnight changes are mainly to add dense fog in for the W up to/incl I-80. We'll wait on cues to decide to expand the advisory eastward. At this point, it is a 50/50 proposition. There should be some breaks develop over the area where it has rained/snowed in the past 12 hrs. But, thus far, the lowest visbys have been on the tops of the Laurels. The visby is now dropping in the valleys of the Laurels, too.

The precipitation is now snow over the eastern zones, and likely mixing with snow close to home with temps getting cold enough. A meager band of heavier precip is forming between UNV and IPT, but should be dissipating and sliding east shortly. Road temps still above freezing in most places except Schuylkill Co where I-81 is already getting coated. It has been snowing there the longest. Continuing to mention a thin, slushy coating for the next 3-6hrs, mainly E of the Susq mainstem. ---------------------------------------- KEY MESSAGE 2: Mid-February thaw still on tap.

Temps really not any milder Monday vs Sunday. So the warm up starts on Tues. A minor warm front will pass through Monday evening/early night and a weak shortwave aloft running through at the same time could make a few sprinkles across the nrn mtns and Poconos.

Thicknesses get thicker on Tues-Wed. Maxes get up to the m50s in the S and m40s N. Then, a complex/wavy mostly-east-to-west front starts to waggle around PA later Tues night. That will allow a low pressure area and associated moisture to slide in from the WNW and rain on much of the area. The srn tier where they need the rain the most could miss out, as most of the rain will be across the nrn half to 2/3rds of the CWA. Despite a bit of cooling aloft, it should dry out on Thursday, and temps will get back into the 50s just like on Wed.

Another wave of warm advection ensues toward Friday. Depending on timing of precip arrival, there could be some mixed precip for the NE half or so of the area as we head into the weekend. ----------------------------------------

KEY MESSAGE 3: Late-Feburary cold snap taking shape.

The warm spell isn't here for the long haul. Temps get cooler on Sat and likely continue downhill on Sun. Another shot of precip is possible late in the weekend, and much of that could be snow per blended temps at that range. We'll probably be back to slightly below normal temps on Monday.

AVIATION /06Z MONDAY THROUGH FRIDAY/

Area of wet snow and light rain associated with a weak low moving off the coast, is now pulling out of our area.

Main issue overnight into at least early Monday morning will be low clouds with patchy dense fog. Expect fog to be most dense in areas that have a bit of clearing, given snow cover. Overall expect a wide range of conditions both over space and time.

Conditions should slowly improve after sunrise, but with cold air at low levels and inversion in place, improvement may be limited with the high pressure building into the area.

Weak low pressure systems will bring some spotty precipitation to the region at times throughout the week, mainly across the north. Temperatures will be on the mild side, more like mid March, so rain will be more likely than other types of precipitation.

Outlook...

Tue...Patchy fog possible early, then mainly dry.

Wed...IFR -RA/cigs N, MVFR -RA/cigs elsewhere.

Thu...Dry early, then rain later in the day with restrictions possible.

Fri...Rain lingers, restrictions possible.

CTP WATCHES/WARNINGS/ADVISORIES

Dense Fog Advisory until 11 AM EST this morning for PAZ017-024- 025-033-034.