Deadly Weather Set to Return This Week
A strong upper level ridge of high pressure shown below (500mb heights) will remain entrenched across central US, strengthening during the early part of the week, and moving into the Ohio Valley later in the week, NWS said
The system will cause potentially deadly weather with heat and humidity prevailing.

Maximum Heat Index (ºF) – July 20, 2011 forecast by NWS.

Chance of Mean Heat Index > 100ºF. Click images to enlarge.

Chance of Mean Heat Index > 105ºF. Click images to enlarge.
Hazard Assessment Map: EXCESSIVE HEAT

Oppressive Heat and Humidity Set to Return
Excessive Heat Warnings, Watches and Advisories Issued for 3 Dozen States

The high pressure ridge will cause high temperatures and high heat indices forecast at higher than 100ºF plus for Mon/Tues, and 105ºF plus for Wed/Thurs/Fri, NWS said.
Selected Weather Stories

Synopsis: After a stretch of warm summer like temperatures, the longest stretch of oppressive heat and humidty of the season is upon us. Temperatures will continue to climb through the 90s by the end of the weekend with dew points remaining elevated. By the new work week, temperatures are expected to build towards or even past the 100 degree mark in portions of Missouri and are expected to surpass 100 degrees over much of Kansas. However, humidity values will be lower. Unfortunately, heat index readings will climb between 105 and 115 each day through next Friday. Little in the way of nighttime relief is expected due to light winds and temperatures remaining near 80 degrees.
An excessive heat warning is in effect for much of Kansas and Missouri through 7pm Friday. This is a dangerous situation! Please check on relatives, neighbors, and friends who may not have resources to stay cool in these conditions. Drink plenty of fluids and refrain from long periods of outdoor exposure; heat related illnesses can occur in minutes. (Source: NWS)

Sunny, hot and humid conditions with highs up to 105 through at least mid-week. Elevated humidity levels will help create high heat index values, resulting in an Excessive Heat Warning to be in effect across the region into mid-week. NWS
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