Wiley’s Weather

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Wiley Butler | National Weather Service Cooperative Weather Observer
An anomalous, stout high pressure aloft weather system located over southern Colorado and northern New Mexico produced heat index values across Natchitoches Parish of 110 – 116 degrees after noon Sunday, July 10.  Weather sensors (ambient temperature + relative humidity value combined) indicated a 116 degree heat index value at Natchitoches during the 3-4 p.m. hours. 

This article published in the July 14, 2022, print edition.

This is a very rare, extreme weather event.  Heat index values of this intensity may have been observed during the brutal summers of 1936, 1980 and 2011, but there is no official climate recordation, until this Sunday. 
NWS Cooperative Weather Observer Wiley Butler provided this graphic showing how heat indices are calculated.

A unique combination of a stout 500 millbar high pressure cell aloft over southern Colorado at 598 decameters at 500mb and a cold front crossing Natchitoches Parish (near 18z) caused compressional warming, in combination with relative humidity value, caused the 116 degree heat index value. 
On Sunday, July 10 at 1:34 p.m. the official temperature was 95.8 degrees. By 3 p.m. the heat index value was 116 degrees.

The Natchitoches Fire Department reported Monday they received no emergency calls for heat stress and/or heat stroke illness for this event.
During Saturday afternoon, the official maximum temperature rose to 103 degrees at Natchitoches’ official National Weather Service, NOAA, NCEI climate site, which replaced a 1998 daily record high temperature for the date.  Natchitoches’ official climate records date back to 1893.