January weather forecast
Pennsylvania, USA

January in Pennsylvania is distinguished as the coldest month of the year, with the mercury frequently venturing below 0°F (-17.8°C). The average temperatures for this month hover from 19°F (-7.2°C) to 33°F (0.6°C). The state's geographical disparities, especially the mountainous regions, play a vital role in influencing its winter climate. For instance, areas near Lake Erie and the mountainous interiors witness considerably more snow, often accumulating over 100" (2540mm) throughout the winter season. In contrast, eastern valleys, being on the leeward side of the mountains, tend to be warmer and receive less precipitation.

When compared to December, January sees a noticeable drop in temperatures, solidifying its reputation as the harshest winter month. Furthermore, February follows suit, though with slightly milder temperatures and retaining its status as the snowiest month. January's cold is accompanied by frequent snowstorms and, at times, heavy snowfall. Locations like Smethport have recorded extreme lows, with the temperature plummeting to an astonishing -42°F (-41.1°C) on January 5, 1904, marking one of the most extreme climatic events in the state's history. Fog, coupled with overcast skies, is a common sight, limiting the appearance of sunshine and further emphasizing the wintry atmosphere that dominates Pennsylvania during this month.

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• Philadelphia - January »
  January and February are months with the least rain in Philadelphia when the rain falls for 7.3 days and typically aggregates up to 0.83" (21mm) of rain. The months with the least rainfall in Philadelphia are January and February Rain falls for 7.3 days and accumulates 0.83" (21mm) of rain.
• Pittsburgh - January »
  In Pittsburgh in January, during 14.4 snowfall days, 3.31" (84mm) of snow is typically accumulated. January and February, with an average relative humidity of 84%, are most humid months in Pittsburgh, Pennsylvania.
• Allentown - January »
  In Allentown, Pennsylvania, during January, snow falls for 5 days and regularly aggregates up to 3.15" (80mm) of snow. Temperature records in Allentown, Pennsylvania, mark January as the coldest month, with highs averaging 34°F (1.1°C) and lows at 21.6°F (-5.8°C).
• Erie - January »
  In Erie, Pennsylvania, in January, during 7.8 snowfall days, 0.28" (7mm) of snow is typically accumulated. In Erie during January, the rain falls for 4 days and regularly aggregates up to 0.43" (11mm) of precipitation.
• Reading - January »
  In Reading, in January, snow falls for 6.4 days, with typically accumulated 2.8" (71mm) of snow. In Reading, in January, during 7.9 rainfall days, 2.17" (55mm) of precipitation is typically accumulated.
• Scranton - January »
  January and September are months with the least rain in Scranton when the rain falls for 5.2 days and typically aggregates up to 1.38" (35mm) of rain. In Scranton, Pennsylvania, during January, the rain falls for 5.2 days and regularly aggregates up to 1.38" (35mm) of precipitation.
• Bethlehem - January »
  In Bethlehem, Pennsylvania, in January, snow falls for 7.8 days, with typically accumulated 3.23" (82mm) of snow. In Bethlehem, in January, during 7.8 snowfall days, 3.23" (82mm) of snow is typically accumulated.
• Lancaster - January »
  In Lancaster in January, during 6.8 snowfall days, 3.15" (80mm) of snow is typically accumulated. The months with the lowest UV index in Lancaster are January, February, November and December, with an average maximum UV index of 2.
• Harrisburg - January »
  January and February are months with the least rain in Harrisburg when the rain falls for 5.7 days and typically aggregates up to 0.71" (18mm) of rain. In Harrisburg during January, the rain falls for 5.7 days and regularly aggregates up to 0.71" (18mm) of precipitation.
• Altoona - January »
  The month with the most snowfall in Altoona is January, when snow falls for 15.9 days and typically aggregates up to 5.28" (134mm) of snow. The month with the most snowfall in Altoona is January, when snow falls for 15.9 days and typically aggregates up to 5.28" (134mm) of snow.
• York - January »
  The month with the most snowfall in York is January, when snow falls for 6.8 days and typically aggregates up to 2.4" (61mm) of snow. The month with the least rainfall in York is January, when the rain falls for 6 days and typically collects 1.06" (27mm) of precipitation.
• State College - January »
  Temperature records in State College mark January as the coldest month, with highs averaging 31.1°F (-0.5°C) and lows at 18.7°F (-7.4°C). In State College, Pennsylvania, in January, during 10.5 rainfall days, 2.28" (58mm) of precipitation is typically accumulated.