Impressionist Landscape

Step 1 · The picture and its painter

A small board, an approximate date

Ernest Lawson’s Impressionist Landscape (Westchester County, New York) is a small oil on board, 6 × 8¾ inches, recorded as a Huntsville Museum Association Purchase, accession 1985.09. The museum catalogues it as about 1909. Its public entry names no season, exact site or painting day, and does not explain the basis of the approximate date.

Lawson settled in Washington Heights in 1898. The National Gallery of Art describes his next two decades of landscapes incorporating the buildings and bridges of an expanding New York. The Westchester place-name on this board belongs beside that wider interest in the region; it does not document a visit in any particular month.

Huntsville presents the work in its American Impressionism collection, whose introduction emphasizes light, colour and expressive brushwork. The Smithsonian’s biography describes Lawson’s heavy impasto, or thickly applied paint, and his preference for winter scenes along the Hudson and Harlem Rivers. The green foliage and flowers in this picture are worth noticing against that general preference.

Step 2 · The seasonal comparison

A cool growing season at Mount Hope in 1909

At Mount Hope, May–September 1909 averaged 65.3 °F (18.5 °C). It is the coolest of the 15 complete May–September seasons retained from this station’s file. Both neighbouring years were warmer. This comparison puts the approximate date beside a measured growing season; it does not establish that Lawson painted during that season or that the scene records its temperatures.

Each seasonal mean uses all 153 days, taking the midpoint between each day’s high and low before averaging. The search covers the file’s 1896–1929 span. The 15 qualifying seasons run from 1897 to 1923, with gaps between years. The rank describes these archived readings; instrument exposure and long-term comparability have not been verified.

Step 3 · Check the months and gaps

Two stations, with different limits

The daily files from Scarsdale and Mount Hope contain thermometer readings from Westchester. Each line below belongs to one station. Their locations and instrument surroundings differ; neither is established as the site Lawson painted.

Both high and low readings must be present and pass the archive’s quality checks on every calendar day. A single missing or rejected reading leaves the monthly mean blank; no neighbouring station fills the gap.

Scarsdale supplies 11 of the 15 monthly means, but none of the three full seasons qualifies. Only 6 complete seasons qualify anywhere in its 1904–1991 file; the incomplete 1908–1910 seasons cannot be ranked against them. The linked data retain the excluded dates and source flags. Fahrenheit is converted before rounding.

The precipitation columns need a different caution. Many zero entries carry NOAA’s flag for a missing amount presumed to be zero. They do not prove a measured dry day. This page therefore publishes no complete rainfall totals or wetness rankings. NOAA’s format guide explains these flags; the data file keeps them visible.

Step 4 · What a visitor can take away

Context for looking, no test of the painted sky

The foliage and flowers suggest a growing season; the comparison shows that such a season need not have been especially warm. That is context for looking, not a confirmation of the depicted weather. The records cannot identify Lawson’s day, show whether the painted sky was observed or remembered, or say what he changed. An account of his thick paint is not a weather measurement, and an appealing match to one month would not date the board.