Heat — Southeastern St. Lawrence, New York

2025-06-23 to 2025-06-24 · Southeastern St. Lawrence, New York

Event narrative

Dangerous heat across the region for both June 23rd and 24th with daytime temperatures in the lower to mid 90s and dewpoints in the 70s creating heat index values between 95 and 105 degrees.

Wider weather episode

An upper level area of high pressure, this time of the year called a heat dome, was centered across the Appalachians/Mid-Atlantic states ridging across the northeast including NY and New England.

This airmass on June 23rd was considerably hot and humid with temperatures in the 90s and oppressive dewpoints in the low to mid 70s. Heat index values ranged from the mid 90s across the Adirondacks to the 100 to 110 range across the St. Lawrence and Champlain valleys.

Temperatures were only a few degrees lower for most of NY on June 24th but still dangerous hot with heat index values mainly between 95 and 105. Health related impacts were not available.

Here were temperature records for the three recognized climatological sites (Plattsburgh, Saranac Lake and Massena) in northern NY.

June 23rd:

Plattsburgh - 101 degrees, surpassing the daily record and TIED the ALL-TIME Warmest Temperature.

Saranac Lake - 90 degrees surpassing the daily record.

Massena - 92 degrees TIED the daily record.

June 24th:

Plattsburgh - 99 degrees, surpassing the daily record.

Saranac Lake - 90 degrees TIED the daily record.

Massena - 93 degrees surpassing the daily record.

Source: NOAA Storm Events Database, event_id 1257534. Narrative written by the NWS forecast office that issued the report.