The hottest September 4 on record was in 2002, when the temperature in Liepāja reached 28.9 degrees.
Unusually hot for September, it is hot across much of Europe, from northern Scandinavia to the Balkans.
Thursday will also be hot in Latvia. The weather will remain dry and sunny, with fog forming at night and in the morning. Slow easterly winds will prevail.
Minimum night-time temperatures will be 11-18 C, maximum daytime temperatures 23-28 C, and up to 29-30 C in south-western Kurzeme.
A yellow heat alert is in force in western and central Latvia on Thursday.
In Riga, dry weather with a slow breeze. Minimum air temperature at night will be around 17 degrees, maximum during the day around 27 degrees.
