The ridge of high pressure causing this week's record-setting heat wave continues to drift east today, and will inflict extreme June heat across most of the central U.S. and Midwest on Thursday. Triple-digit heat (and heat indices) will be widespread from the Midwest (Chicago, Detroit, Cleveland) to the Mississippi and Ohio River Valleys (St. Louis, Louisville, Memphis). Ann Arbor, Michigan has reached 100° as of 4pm EDT. Heat advisories spread from Kansas north to Michigan, and as far southeast as North and South Carolina.
On Wednesday, 16 all-time record highs were broken or tied from Wyoming to Kansas, and 47 month-of-June records were either broken or tied. 66 warm overnight low records were also tied, 8 of which were all-time records for the month of June. The temperature did not get below 81° in Lamar, Colorado Tuesday night. The overnight low temperature is an important barometer for public health and safety in extreme heat waves; if the mercury does not drop significantly, our bodies (the sick and elderly, in particular) cannot recuperate.Figure 1.
Heat advisories (pink) from Kansas north to Michigan, and as far southeast as North and South Carolina on Thursday, where heat indices are expected to reach 105, as much as 110 in some places.Our Weather Historian, Christopher C. Burt, wraps up yesterday's significant temperature records:
• Lamar, Colorado hit 112°, which is the city's hottest ever reading, beating 111° measured a few days ago and also on July 13, 1934.
• Dodge City, Kansas finally broke free of its multiple 110° previous all-time records with 111° on Wednesday. Dodge City has one of longest periods of record in the United States, with temperature records beginning on September 15, 1874.
• Hill City, Kansas hit 115° as it did on Tuesday as well, again just 1° short of all-time Kansas STATE June record of 116° set at Hugoton on June 25, 1911.
• Tucumcari, New Mexico hit 108°, just 1° short of all-time record as was the case in Goodland, Kansas and many others.Waldo Canyon Fire gains 5,000 acres, still 5% contained
18,500 acres (up from 13,5000 on Wednesday) have been consumed, and $3.2 million spent fighting, in the Waldo Canyon Fire which is burning northwest of Colorado Springs and encroaching on the city. The fire remains 5% contained. Around 32,000 people have been evacuated as of Thursday morning as fire fighters continue to battle the blaze, with some help from the weather. Colorado Springs is forecast to reach 97° on Thursday, though it will be slightly cooler in the hills where the majority of the fire is burning. The red flag warnings have been dropped as wind speeds calm to 5-10 mph out of the northwest. However, humidity will still be relatively low, around 15% at the peak heat of the day. Thunderstorms are in the forecast, which creates the threat of lightning-induced firesA giant plume from the Waldo Canyon Fire hovers high above Garden of the Gods near Colorado Springs, Colo. on Saturday, June 23, 2012. The fire is zero percent contained and has consumed 2500 acres. Voluntary and mandatory evacuations were taking place across the west side of Colorado Springs. Tankers were dropping fire retardant in front of the advancing flames. (AP Photo/Bryan Oller)In the Tropics…
An African easterly wave in the central main development region of the North Atlantic is still producing some disorganized thunderstorm activity. The circulation in the wave is moderate but somewhat displaced from the strongest thunderstorm activity, though given the moderate wind shear the wave is experiencing that's not surprising. Sea surface temperature is around average, 28° C (82° F), which is warm enough to support tropical development. The National Hurricane Center continues to give this wave a 10% chance of developing over the next 48 hours.
There are a couple more tropical waves expected to leave the coast of Africa in the next week or so, neither of which are showing any signs of development in the models.