The low temperature on Sunday was 24 degrees at Hector Int’l. On Monday, the sensor at the airport recorded a maximum temperature of 93 degrees. That is a difference of 69 degrees in approximately 36 hours. That is tied for the 5th highest difference over a two day period since records started in 1881.
The record occurred in May, 1926. On May 3, 1926 the low was 18 degrees. The following day on May 4, the high temperature was 93 degrees for a difference of 75 degrees over the two days. Other notable two day differences occurred on January 6/7, 1924 from -35 degrees to +36 degrees and from April 14/15, 1926 as the temperature changed from a low of 14 degrees to a high of 85 degrees, both 71 degree differences.
It should be noted that modern electronic thermometers detect sudden rises and falls of temperature more efficiently then the old mercury or alcohol thermometers used in the past; yet, the difference from Sunday morning to Monday afternoon was striking.
The coldest temperature so far this season, through yesterday, was a 25 degree reading back on September 23. If not for cloud cover on other mornings, we likely would have been much colder. That has been particularly true in recent days.
This past Sunday morning for example, the low in Fargo was 30 degrees. Much of the night was cloudy and that kept the cooling near the surface to a minimum, but where the sky cleared the temperature plummeted. Aberdeen where it was clear, the temperatures fell to 14 degrees that morning. Temperatures in the teens were found as far south as Iowa, with Sioux City recording 15 degrees and Spencer, 13 degrees. All of those temperatures were records for the date.
Perhaps the most impressive low on Sunday morning was the 32 degree low in Tulsa, Oklahoma, as that was the earliest known freeze for that location. Oklahoma City also recorded their earliest freeze on record the following day. So although it has certainly been cold lately, thanks to cloud cover, no records have been broken.
Nearly 100 years ago, on July 10, 1913, a temperature reading of 134 degrees was recorded at the Greenland Ranch in Death Valley, California. At the time that was the highest temperatures recorded with proper measuring techniques anywhere on earth.
Nearly a decade later on September 13, 1911 a report of a temperature of 136 degrees was allegedly taken at El Azizia, Libya to establish a new world record that still holds to this day. That is until now. The World Meteorological Organization recently decided to drop that particular reading from the record book. There is always been some suspicion to that reading in Libya in 1922 and after much research it was determined that indeed that temperature was likely bogus.
Therefore, that temperature set nearly a century ago in Death Valley is now considered the warmest temperature recorded in the world. So if you have ever had the chance to go to Death Valley, you can now officially tell your friends that you visited the hottest place on earth.
On July 19, 2011, the sensor at the Moorhead Municipal airport was reporting a dew point of 88 degrees. Many of us in the weather community did not give much credence to the reading as that sensor gives calculated dew point temperatures three to five degrees higher than Hector Int’l no matter the time of year (and it still does, no matter what the vegetation type if any, time of day, month or season).
That day out of curiosity, I drove to the Moorhead airport, took a reading using an old fashioned sling psychrometer, which was used for years to measure relative humidity and dew point based on the cooling of a thermometer by evaporative cooling. I came up with an 83 degree reading on two tests, which was what the Fargo airport was reporting. Yet, in the end that 88 degree reading, which surprised many of us, was used as a new state record for Minnesota.
I put that record in this context; although Roger Maris’ record of 61 homers in a season has technically been broken, it was done so by questionable means. I think Roger Maris holds the true record and a humidity sensor that reads high consistently, in all seasons, perhaps should have as asterisk next to its record
Yesterday was the 13th time this month that Fargo Moorhead recorded a low temperature above freezing. That ties 2010 for the most such days in March. You may think that is a typo, as so much has been written about this month being similar to 1910, but it was just two years ago that we set that record. Although, March 2010 was no where near as warm as this month for daily high temperatures, it was a very warm month for nightly lows.
From March 7-15, 2010, the low temperature remained above freezing. Many of those days the low was either 34 or 35 degrees with a high between 37 and 40 degrees. That entire week was regularly foggy and dreary, but that continuous period with above freezing temperatures lead to a rapid snow melt and like 2009, to an early major flood.
The low this morning was 34 degrees at Hector Int’l so it appears we have now broken that record from 2010 and we are likely to see above freezing low temperatures every day this week adding to that record.
Fargo Moorhead has recorded 13 daily records or ties this month. That includes 5 high temperature records, one high temperature tie and 6 new records for warmest minimum temperature. Plus, we may yet set another daily maximum minimum before the month is through.
The most impressive record set this month was the low temperature back on March 18. The low that morning was 60 degrees. Not only was that the record for the warmest minimum for that date by an incredible 19 degrees, it was also the warmest minimum temperature for any day in March since 1881. The previous record was a 48 degree low set on three different occasions with one occurring on March 23, 1910 and the other two on March 24 and 25, 1945.
To put that 60 degree low temperature in perspective, the record high for March 20, just two days later is just 62 degrees. Therefore, that 60 degree low will likely be a record for a long time to come.
As many of you already know, the high temperature on Wednesday was 90 degrees. Or was it? The Moorhead airport recorded a high of 84 degrees that day, my home thermometer registered 86 degrees, our cooperative observer reported 88 degrees as did the reporting site at NDSU.
It was yet another example of differences in temperatures caused not only by natural variations, but more importantly where a thermometer is located. The official site at the airport is located near the main runway to maximize safety for aircraft, not for registering the most accurate temperature reading. Jet exhaust, a light breeze off the pavement nearby and other issues can cause that thermometer to be far different than what you may experience in your backyard.
Yet, the airport is the official reading in town and therefore it is accurate to say that the high on Wednesday was the latest 90 degree reading locally since 1993 and our 10th and probably last 90 degree day in 2011.
Tuesday evening, the automatic sensor at the Moorhead Airport reported a dew point temperature of 88 degrees. This was prematurely reported by a number of local and national media as a new state record.
It was premature because the quality of the reading must be evaluated before it can be proclaimed a record, and it appears that the reading had a few problems. We went out to the site on Wednesday and found the sensor surrounded by moisture-producing corn, sugar beets, and very tall clover without a buffer as is required. Also, the field had standing water all around which doubtlessly added greatly to the humidity and would not be considered representative of the surrounding countryside as a whole.
Finally, the sensor at Fargo’s Hector Airport was simultaneously registering a dew point of 83 which, although very high, was five degrees lower than the Moorhead reading. Just like when track and field records do not count if they are wind aided, this dew point record will also fail to qualify as a record.
A couple of links you may want to read:
Hottest Place on Earth?
Unreliable Dew Points
This week’s stretch of humid weather brought with it some extremely warm low temperatures. On July 17 the morning low was 79 degrees, and then two days later, on July 19, the morning low was 80 degrees. There have been only three days since 1881 with a low temperature of 80 degrees or higher.
Therefore, those morning lows of 79 and 80 degrees would have been some of the warmest lows ever recorded. Although the morning lows were exceptionally high, an official low is over a period from midnight to midnight and on both of those mornings the temperature did drop well below those levels by the end of the day. In fact, neither of those days ended up even breaking a record for the high minimum as the temperature dropped to 73 and 70 degrees on those two days for the official low.
We may not have recorded any historically high low temperatures, but we did have five straight days with a low of 70 degrees or higher which is the 3rd longest such period on record.