Same-Day Record High and Low Temperatures
Same-Day Record High and Low Temperatures
Last week Valentine, Nebraska saw its temperature fall from a record 76° at 3 p.m. (CST) on November 21st to 10° by 7 a.m. on November 23rd. A drop of 66° in just 40 hours. The low of 10° was not a record and, of course, almost two days separated the two extremes. However, there have been rare occasions at a handful of locations in the U.S. when the record maximum and record minimum temperatures were broken on the same day. Here is a summary of those events.
There are basically three different climatic conditions that can lead to record highs and lows being set on the same day. One condition is when a very strong and fast moving cold front passes over a location causing the temperature to drop dramatically (as occurred in Valentine last week). The second, and more common event, occurs when the humidity is very low allowing for strong diurnal temperature swings to occur. This is especially true for locations in the Great Basin or mountain valleys of the West, usually during the summertime. The third situation is when a location has a very narrow spread of average temperatures between day and night and thus also a narrow spread between their record daily highs and lows. This is the case for tropical areas or locations right along the Pacific coastline. Here are some examples of all three cases:
COLD FRONT PASSAGE
On November 11, 1911 the most extreme cold front in U.S. meteorological records swept quickly across the Great Plains and Midwest. Kansas City, Missouri fell from 76° to 11° in 12 hours. Oklahoma City fell from 83° to 17° and Springfield, Missouri from 80° to 13° officially. In all three cases the cities recorded both their record high and record low temperature on November 11th.
The thermograph trace from Springfield, Missouri actually shows that the high temp was at least 81° on November 11th at around 3:45 pm. It also shows that by midnight that same day the temperature had fallen to 10°. The ‘official’ range of temperature for the day of 80° to 13° is not correct if the thermograph is accurate. The office only reported hourly temps for their daily summary and concluded that the 11 p.m temp of 13° was the lowest for the day when, in fact, it had reached 10° by midnight). A drop of 40° occurred in 15 minutes between 3:45 p.m. and 4:00 p.m. The 71° drop in eight hours is almost unprecedented in meteorological records although two locations in Arkansas (Rogers and Fayetteville measured a 72° drop in temperature during the same period from 81° to 9°). Graphic from NWS Springfield office.
DRY AIR TEMPERATURE DIURNAL SWINGS
The San Luis Valley in south-central Colorado is the state’s driest location and its high altitude (around 7,500’) means very cool nighttime temperatures are common in the summer, whereas during the daytime the intense solar radiation causes the thermometer to rise dramatically.
The beautiful high and dry San Luis Valley in south-central Colorado experiences enormous diurnal temperature fluctuations. The valley’s principle town of Alamosa has recorded four days of the year that measured both their warmest and coldest day on record. Photo by Steve Garufi.
The town of Alamosa has four days of the year that have recorded both their record highs and lows. Amazingly, three of these four days occurred consecutively:
August 24, 2002: Record high of 85°, record low of 33° (52° range)
August 25, 2002: Record high of 87°, record low of 30° (57°)
August 26, 2002: Record high of 88°, record low of 31° (57°)
Alamosa also saw its temperature rise from a record low of -18° to a record high of 58° on February 21, 1958, an astonishing 76° rise over about 15 hours. An even more astonishing diurnal spread of temperature was purportedly recorded at Juniper Lake, Oregon on May 2, 1968 when the temperature rose from 0° to 81°. I am unable to tell if either of these readings were records for that site and day.
Other places that have had daily high-low records as a result of diurnal heating (listed chronologically) include:
Coalville, Utah on July 10, 2003: 37° to 100° (63°)
Delta, Utah on July 10, 2003: 42° to 107° (65°)
Safford, Arizona on August 25, 2002 from 52° to 105° (53°)
Rapid City, South Dakota on August 16-17, 2002 from 39° to 101° (This was actually a change from the afternoon of August 16th to the morning of August 17th, so not actually a single day ‘double-whammy’, however, it is especially notable since the 101° temperature was just 5° shy of the all-time monthly high record and the 39° was just 1° shy of the all-time monthly low temperature record.
Park City, Utah on August 15, 2002: from 39° to 89° (50°)
Park City, Utah on August 11, 2002: from 36° to 87° (51°)
Paso Robles, California on January 9, 1999 from 21° to 74° (53°)
Sioux City, Iowa on May 16, 1997 from 33° to 91° (58°)
Pueblo, Colorado on July 15, 1993 from 52° to 101° (49°)
Pine Valley, Nevada on July 30, 1989 from 30° to 97° (67°)
Deeth, Nevada on September 21, 1954: from 12° to 87° (75°)
Bakersfield, California on January 3, 1930 from 23° to 75° (52°)
In the book Nevada’s Weather and Climate, by John Houghton et al, (published by the Nevada Bureau of Mines and Geology, Special Publication 2, 1975), the authors claim that the temperature at Sunrise Manor (just 10 miles northeast of McCarran Airport in Las Vegas) rose from a record low of 48° to a record high of 119° on July 13, 1972, a 71° range. This is hard to believe since both figures would exceed the all-time monthly high and low temperatures for July at the official Las Vegas site at McCarran Airport (56° on July 21, 1940 and 118° on July 26, 1931).
Sunrise Manor, an eastern suburb of Las Vegas, apparently may have seen its temperature rise from a record low of 48° to a record high of 119° on July 13, 1972. Photographer unknown.
NARROW DIURNAL SPREAD OF AVERAGE AND RECORD TEMPERATURES
There may be many locations in Hawaii, Florida, and Pacific Coastal areas that have experienced record highs and lows on the same day that I am unaware of. This is because they are so unremarkable and consequently go unnoticed or unreported. Here are a handfull I do know about:
Eureka, California on September 23, 2006 from 42° to 82° (40°)
Vero Beach, Florida on September 14, 2005 from 70° to 92° (22°)
Olympia, Washington on March 14, 2005 from 25° to 67° (42°)
Hilo, Hawaii on May 25, 2003 from 60° to 91° (31°)
Hilo, Hawaii on May 26, 2003 from 60° to 88° (28°)
Melbourne, Florida on May 22, 1998 from 68° to 97° (29°)
San Francisco (airport) on December 23, 1990 from 28° to 64° (36°)
Astoria, Oregon on March 15, 1988 from 28° to 61° (33°)
Miami, Florida on August 11, 1984 from 70° to 96° (26°)
This graph is typical of the narrow range of temperatures that Hawaii enjoys year-round. Hilo has had two days with same-day record highs and lows. Its all-time absolute range of temperature is from a record low of 53° in February 1953 to a record high of just 94° in May 1966.
As one can see, these daily ‘extremes’ would be perfectly normal temperature spreads for most places in the country. The site with the smallest extreme range of temperature (for an entire period of record year-round) is Honomu Mauka, Hawaii (on the Big Island) which has so far seen an absolute temperature range of just 35°: from a record low of 49° to a record high of 84°. The U.S. site with the greatest range of record extremes (over an entire period of record) is Fort Yukon, Alaska with 178°: from a record low of -78° to a record high of 100° (which is also the Alaskan state record high).
I should also mention that there is possibly a fourth cause of daily record highs and lows: the Chinook wind phenomena. Chinook winds account for the greatest 24-hour temperature change ever recorded on earth when, in Loma, Montana, the temperature rose from -54° on January 14th to 49° on January 15th in 1972: an astonishing 103° rise. I am not sure if either of these were daily records and am unaware of any cases of same-day record high/record low temperatures occurring as a result of a Chinook.
If any readers know of other same-day record high/low temperatures please let me know.
Apologies for not providing Celsius conversions in this blog. It would make the blog almost unreadable with so many temperature statistics.
Christopher C. Burt