Of particular interest, the European model predicts a high of 106 degrees Sunday, which would tie D.C.’s highest recorded temperature (established Aug. 6, 1918, and matched July 20, 1930).

The GFS model comes close to this predicting this monumental temperature Sunday, calling for a high of 105 degrees in D.C. (see image at the top of this post).

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But it is premature to confidently call for temperatures this high since the exact intensity of the heat wave is uncertain and will evolve. Model forecasts of specific temperatures more than a few days ahead of time aren’t terribly reliable. The safe forecast is to say that there is the potential for extremely hot weather, without getting too specific.

Simulations of the European model with input data tweaked, known as the European ensemble system, predict less extreme highs in the upper 90s, on average (Friday through Sunday).

On the hotter side, the average prediction from the GFS ensemble system shows highs of 99, 101, 103 and 100 between Friday and Monday.

In summary, available forecast data present a strong but not surefire signal for excessive heat by late this week.

The combination of heat and humidity could be particularly brutal. The National Weather Service predicts a heat index of 106 degrees Saturday and says there’s a 28 percent it could exceed 110.

The extremely hot weather predicted would result from the influence of the massive heat dome expected to develop in the Heartland during the first half of this week. By the weekend, it may well stretch from coast to coast, enveloping the southern two-thirds of the Lower 48.

The exact coverage and intensity of the heat dome will determine whether the heat in the D.C. area is fairly ordinary, near-record levels, or even historic.

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Over the last few years, D.C. has experienced somewhat of a reprieve from headline-generating hot weather. Its last 100-degree reading was way back on July 26, 2012. That 100-degree reading capped a scorching three-summer stretch, the hottest on record, in which D.C. saw the temperature hit at least 100 17 times.