From Sean Bellafiore:
Saturday's high of 108° at the Waco Airport makes it 5 days in a row with record-setting high temperatures. Relief from the record setting heat is on the way, but we'll have to get through two more afternoons of record-heat. We'll start the day Sunday with temperatures in the middle and upper 70s as afternoon highs range from 101° to 109°. Sunday's record of 106° should be broken.
A cold front will slowly creep toward Central Texas during the day Monday. Unfortunately, the front will not arrive fast enough to bring cooler weather during the day as high temperatures will again range from 101° to 109°. Monday's high of 107° will be in jeopardy. Monday's front will cause winds to shift to come more form the northeast late in the day and as the cold front inches through Monday night, it may spark a few isolated showers. Overnight rain chances Monday into Tuesday remain only near 20%.
The cold front will continue to move through at a snails pace keeping the low chance of rain in the forecast Tuesday too, but relief from the oppressive heat should be felt across most of the area. Highs Tuesday should only reach the upper 90s to near 100°, but heat index values may be as high as 104°. As for Tuesday's rain chances, a few isolated showers or possibly a strong storm may pop-up during the day. Any storms that form may contain strong wind gusts and frequent lightning.
The cold front will pass through the area completely by Wednesday. Fortunately, the upper ridge of high pressure responsible for our current heat wave should be shunted well off to our west. Despite the distance from the high, temperatures for the middle and the end of next week will still be a few degrees above average, ranging from 97° to 103° each day with mostly clear to partly cloudy skies. Next weekend looks hot and dry too with highs hovering near 100°, but long-range forecast model data is suggesting a storm system may move close enough to Central Texas by the end of the month for halfway decent rain chances.