textproduct: State College

WHAT HAS CHANGED

* Cold Weather Advisory issued for tonight into Thursday morning

KEY MESSAGES

1) Prolonged Extreme Cold/Wind Chills through the end of January 2) Low risk of plowable snow/minor winter weather impacts this weekend 3) Extreme cold retreats but temperatures remain below the historical average into February

DISCUSSION

KEY MESSAGE 1: Prolonged Extreme Cold/Wind Chills through the end of January

Extreme cold has staying power through the end of January. A cold wx advisory (minimum WCs 10 to 15 below) remains in effect until 10AM this morning. A new cold weather advisory has been issued for tonight into Thursday morning.

The coldest period is yet to come with record challenging minimum temps fcst later this week from Thursday night through AM Saturday. Additional cold wx headlines are likely to be issued to highlight this period of coldest/lowest minimum temps and wind chills.

The cold pattern continues into February with max temps projected to remain below the freezing mark through Groundhog Day. While it appears the extreme cold will retreat, odds continue to favor below normal temperatures through early February.

KEY MESSAGE 2: Minor to plowable snowfall accumulation possible this weekend

There is still plenty of uncertainty with the weekend coastal storm track which directly impacts the location and magnitude of onshore snow potential. The latest NBM probs along with WPC WSSI-P continues to highlight a low risk 10-20% for plowable >2" snow and minor winter wx impacts near and to the east of the I-81 corridor. Odds for heavier amounts remain confined along the Carolina/Delmarva/NJ/New England coast.

Additional forecast information:

The seemingly endless cold cyclonic flow aloft with reinforced shots of arctic air (850mb temps -18 to -24C are below the 10th climatological percentile) will allow for periods of terrain enhanced snow showers with minor snow accums focused across the Laurel Highlands and NW Alleghenies. Flurries will also extend into the central ridge/valley region through late week. Recent Great Lakes ice cover analysis from GLERL/NIC shows 100% concentration on Lake Erie, so available moisture will be limited to upstream connections as mean llvl flow shifts from WNW to NNW by Friday.

AVIATION /12Z WEDNESDAY THROUGH SUNDAY/

Winds have generally diminished to 5-10KTS as surface high pressure begins to nose into the region behind a cold front. Expect winds to remain generally in the 5-10KTS range with only isolated gusts to 15KTS during the early afternoon.

MVFR CIGS and VSBYS in -SN will continue through the morning at KJST and KBFD. Elsewhere, VFR conditions will continue.

Outlook...

Thu-Sat...Periods of lake effect and upslope snow showers remain possible across N/W PA, with restrictions possible; otherwise, chilly and breezy areawide.

CLIMATE

Daily record minimum temperatures possible to close out January:

01/30 MDT: 2 in 1934 IPT: -6 in 1948 AOO: -3 in 2019 BFD: -14 in 1965 STC: -10 in 1977

01/31 MDT: 2 in 1948 IPT: -14 in 1948 AOO: -4 in 2019 BFD: -13 in 2019 STC: -9 in 1948

State College has a very good shot of tying the second longest run (7) of consecutive days with max temp <= 20F (1/25-1/31). The last time this occurred was post-Christmas 2017 (12-28-2017 to 01-03-2018). The longest run of 10 days occurred in January 1893 from the 11th-20th.

CTP WATCHES/WARNINGS/ADVISORIES

Cold Weather Advisory until 10 AM EST this morning for PAZ004>006-010>012-017>019-024>028-033>037-041-042-045-046- 049>053-056>059-063>066. Cold Weather Advisory from 1 AM to 10 AM EST Thursday for PAZ004>006-010>012-018-019-025>028-034>037-041-042-045-046- 049>053-056>059-063>066. Cold Weather Advisory from 7 PM this evening to 10 AM EST Thursday for PAZ017-024-033.