WunderBlog Archive » Weather Extremes

Category 6 has moved! See the latest from Dr. Jeff Masters and Bob Henson here.

The Amazing June Heat Wave of 2012: Part 2 June 28-30. UPDATE: 113° Smyrna, TN

By: Christopher C. Burt, 11:15 PM GMT on July 01, 2012

The Amazing June Heat Wave of 2012 Part 2: The Midwest and Southeast June 28-30

After scorching portions of the West and Plains early last week, the amazing heat wave of June 2012 slid eastward on Thursday, June 28, continuing to astonish us with more all-time heat records. Below is a summary of those.

Set Up for the Heat Wave in the East

The powerful upper level high ridge slid out of the Plains and anchored itself over Tennessee by Friday. Compare the 500 mb charts that I posted in my blog on Friday with those below.



500 mb chart for 7 a.m. on June 27th. Map from Daily Weather Maps, NOAA.



500 mb chart for 7 a.m. on June 30th. Note that another dome of high pressure is developing in the southwest again. Map from Daily Weather Maps, NOAA.

All-time Heat Records Broken or Tied June 28-30

There is no point in listing or even attempting to summarize all of the June monthly records set in the region from Missouri to Maryland and south to Georgia during the June 28-30 period. The 108° in St. Louis on June 28th was perhaps the most significant of those. What was truly astonishing was the number of all-time any month records that were broken or tied.

This is especially extraordinary since they have occurred in June rather than July or August when 95% of the previous all-time heat records have been set for this part of the country (unlike the Southwest where June is often the month that all-time heat extremes are recorded).



Maximum and minimum temperatures recorded across the U.S. on June 29th. Map from Daily Weather Maps, NOAA.

ILLINOIS

109° at Cairo Airport on June 29th broke the all-time record for Cairo (old record 106° on August 9,1930) and also surpasses Illinois’ June state record of 108° at Palestine in June 1954. Chicago reached 100° at both O’Hare and Midway Airports on June 28th, the first 100° reading for either site since 2005. As of July 1st Chicago O’Hare has experienced 18 90°+ days so far this year, the most on record at this point in the season and about what the average number of such days is for an entire year.

INDIANA

106° was measured at Fort Wayne, Indiana on June 28 (tying the all-time record set on 7/14/1936).

KENTUCKY

Paducah recorded 108° on June 29th, an all-time official record (although a previous site in Paducah measured 112° in July 1930). Bowling Green hit 109° on June 29th, short by 1° of Kentucky’s all-time state June record of 110° at St. John’s Academy in June 1936. All-time heat records were broken at Jackson (104°) and London (105°), but these sites have short periods of record.

TENNESSEE

This has been the most intense heat event in Tennessee state history (at least for the eastern two-thirds of the state). All-time records were achieved at the following sites that have significant POR’s (periods of record):

109° Nashville on June 29th (old record 107° on 7/28/1952)

107° Chattanooga on June 30th and July 1st (old record 106° on 6/29/2012 and 7/28/1952)

105° Knoxville on June 30th and July 1st (old record 104° on 7/12/1930)

103° Bristol on June 30th (old record 102° 7/28/1952)

A reading of 113° was reported from Smyrna on June 29th. If verified this would tie the all-time state record for any month: Perryville’s 113° in July and August of 1930. UPDATE: NWS has informed me that the Smyrna site is consistently too hot on sunny days. Hottest temp for TN officially is 110° at Woodbury, still a state monthly record for June.

GEORGIA

Again, this was one of the hottest events in Georgia state history. The following all-time (any month) records were tied or broken:

109° Athens on June 29th (old record 108° on 7/12/1930)

108° Macon on June 30th (ties same on 7/17/1980)

106° Atlanta on June 30th (old record 105° on 7/17/1980)

106° Columbus on June 30th (ties same on 9/5/1925)

The Athens’ reading of 109° was just 1° short of the June state record of 110° set at Warrenton in June 1959. Perhaps some late COOP reports will upset that figure. A reading of 107° was recorded at the Rome WSO Airport site on June 30th, an all-time record (old record 106° on 7/29/1952) for that location (POR 1948-2012). However, the original Rome weather station, with a POR from 1893-2010, reached 109° on July 20, 1913.

SOUTH CAROLINA

This was almost certainly the most intense heat wave in South Carolina’s history. Here’s the run down (all-time any month heat records):

109° Columbia on June 29th and 30th (old record 107° on multiple occasions).

107° Greenville on July 1st (old record 105° set on 6/29/2012 and 8/10/2007, although 106° was recorded by the Army Signal Corps on July, 18, 1887).

Temperatures of 113° were reported from Johnston and the University of South Carolina site in Columbia on June 29th. If verified these would establish a new all-time state heat record for any month at any location (current record being 111° at Camden on June 28, 1954).

NORTH CAROLINA

All-time heat records tied or broken:

105° Raleigh on June 29th and 30th (ties previous record set on 8/21/2007 and 8/18/1988)

104° Charlotte on June 29th and 30th (ties same on 8/9/2007, 8/10/2007, and 9/6/1954).

Southern Pines reported a temperature of 108° on June 30th. If verified this would be a new June state heat record beating the 107° reported from Lake Mitchie in June 1959 but short 2° of a suspicious reading of 110° at Fayetteville on August 21, 1983. There appears to be no data to support the figure from Fayetteville in 1983. The hottest indisputable record for North Carolina is 109° at Weldon on September 7, 1954.

VRIGINIA AND WASHINGTON D.C.

The 104° at National Airport in D.C. on June 29th fell 2° short of the D.C. all-time record of 106° set on July 20, 1930. You may have noticed that 1930 pops up often in terms of all-time heat records in the Southeast.

108° was reported from Petersburg on June 29th. If verified this would be the all-time Virginia state heat record for the month of June (current record being 107° at Lincoln in June 1934). The all-time ‘any month’ record for Virginia is disputed: 110° from Balcony Falls on July 15, 1954 appears suspicious and the Virginia State Climate Office has disallowed it. The next candidate is 109° at Lincoln on July 10, 1936. 109° was also reported at the Williamsburg Airport on July 25, 2010, but this appears to be an unofficial reading.



Surface temperatures at 4 p.m. on July 1st, the last day of the record-breaking portion of the heat wave. The white shaded areas represent temperatures of 105°+. Image from UCAR.

Conclusion

There is no imminent conclusion to this heat wave. As the high-pressure ridge over the Southeast weakens, a new ridge is developing again over the Southwest and threatens to form a broad flat upper-level dome stretching from New Mexico to Georgia. An up-to-date list of all the ‘all-time’ heat records broken at significant sites since June 23 may be found on ‘Wunderground U.S. Records’ under the ‘Climate’ tab at the top of the WU front page (scroll down to ‘Record Extremes’.)

18 of the 298 locations I follow closely (because of their long POR’s and representation of U.S. climate) have already broken or tied their all-time heat records.

It is just July the 1st and the summer has just begun.

Christopher C. Burt
Weather Historian

Heat Temperature

The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.