textproduct: State College

WHAT HAS CHANGED

* Added discussion about potential risk of fire spread on Saturday

KEY MESSAGES

1) Noticeable warmup into Thursday precedes rain and thunderstorms through Thursday night followed by chilly cooldown for the last weekend of March

2) Dry and windy conditions on Saturday may result in a risk of wildfire spread.

DISCUSSION

KEY MESSAGE 1: Noticeable warmup into Thursday precedes rain and thunderstorms Thursday night followed by chilly cooldown into the last weekend of March.

High pressure centered over PA is delivering plenty of sunshine this afternoon. As the high moves offshore on Wednesday, clouds will be on the increase but dry weather will continue. Increasing south to southwest flow will allow temperatures to climb back to/slightly above seasonal averages for late March by Wednesday. The main surge of warmth arrives Thursday: fcst max temps 10-20 degrees above average with potentially more room to the upside if skies trend sunnier. Daily record highs seem out of reach, but could get close (see climate section). Behind the cold front, a gusty NNW wind will help to deliver a 24hr maxT change of -10 to -25 degrees Friday followed by a rather chilly cool down below climo to start the last weekend of March.

The best signal for rain continues to flash between 00-12Z Friday as a strong cold front moves southeastward across PA. Heavy rain and severe storm risks are primarily focused to the west of PA over the Ohio Valley into the Midwest. The D3 MRGL SWO does clip the western periphery of the forecast area as a late night threat could extend from the Ohio Valley into western PA; but odds are that increasing stability with eastern extent greatly reduces the severe risk to the east of the Alleghenies.

KEY MESSAGE 2: Dry and breezy conditions on Saturday may result in a risk of wildfire spread.

Gusty winds from the north and then the west behind the cold front Friday into Saturday will usher in drier air over the course of that 24 hours period. By Saturday afternoon, dewpoints are progged to range from the single digits in the north to the low teens in the south. Combined with temperatures in the mid 30s to mid 40s, this will yield min RH values in the 20s pct across central PA Saturday afternoon. By that time, frequent wind gusts above 25 mph will be mostly confined to the ridges of the Laurels and northern Alleghenies. If that's the case the overall threat for wildfire spread will be less than warning criteria, but we will keep a close eye on the threat and monitor fuel moisture assessments from our forestry partners.

AVIATION /00Z WEDNESDAY THROUGH SUNDAY/

VFR conditions are expected through the 00Z TAF period under increasing amounts of mid and high level clouds. A few showers cannot be ruled out over northern PA Wednesday afternoon, but the probability is too low to include any mentions of rain in the TAFs. If any showers do happen to move directly over an airfield, ceilings may briefly be lower than currently forecast (likely still above 5000 feet).

Outlook...

Thu-Friday...Showers becoming more widespread with perhaps a thunderstorm. Restrictions likely.

Fri PM...Breezy with light rain exiting the southern tier.

Sat-Sun...VFR.

CLIMATE

Record high temperatures for March 26th:

Harrisburg 80 in 1921 Williamsport 78 in 1939 Altoona 79 in 1998 Bradford 73 in 2007 State College 76 in 1949

CTP WATCHES/WARNINGS/ADVISORIES

None.