It has been almost one week since several tornados ripped through the state of Mississippi. The strongest tornado started in extreme eastern Louisiana and then remained on the ground for 149 miles as it moved across much of central Mississippi. At peak intensity, the tornado was rated an EF-4 on the Enhanced Fujita scale as it moved through Yazoo City. Ten people died in that storm with dozens more reported injured.
Continuous tornado damage paths in excess of 100 miles are unusual, but do happen on occasion. More often, damage paths are broken up into segments as tornados disappoint and reform from the same thunderstorm, but that was not the case with this particular storm. The longest known continuous damage path from a tornado occurred in 1925 when the “Tri-state Tornado” caused continual damage from southeastern Missouri, through Southern Illinois, then into southwestern Indiana over a distance of nearly 220 miles killing nearly 700 individuals with hundreds more injured.
I think it is safe to say that the number one topic of conversation in this area is the weather. Several times in recent weeks, I have overhead comments about how warm this spring has been. If you need some statistics to back up your next conversation, you can mention that to this point, this spring season has averaged the warmest low temperatures since 1881. We are a full two degrees warmer than any other spring to this point when dealing with our wake-up temperatures.
This spring is currently ranked 2nd for high temperatures, with only the year 1910 recording warmer daytime highs. When combined, the average temperature in 1910 was slightly warmer than this year, so we are currently ranked as the 2nd warmest spring to this point. It may interest you to know that 1910 is currently ranked as the 5th warmest spring on record and it is likely this year will eventually fall down the list as well before spring ends on May 31.
The cold season is our dominate season and most of us long for the warmth of our usually short warm season. Now that we have experienced a few 70 degree days, if you are a warm season fan, you will be happy to know that on average Fargo Moorhead records 119 such days a year.
Looked at in another way, nearly one day in three over the course of a calendar year, the high temperature will be at or above 70 degrees. Of those 119 days averaged at or above 70 degrees, 61 will reach or exceed 80 degrees and on 13 days the high temperature will be recorded at or above 90 degrees. We average less than 1 day per year with a high at or above 100 with only 86 such days recorded since 1881.
Granted, average does not mean much, but this year should fall some where in between our historic range of 85 such days in 1883 to the 146 days observed above 70 degrees in 1988.
This spring has been quite a turnaround from the past few years. To put this into perspective, the first half of climatological spring (March 1 through April 15) has averaged about 12 degrees warmer than 2008 or 2009 to this point and 9 degrees warmer than 2007. March finished as the 4th warmest on record and the first half of April was the 5th warmest since 1881. You would have to go back to 2005 to find a spring with temperatures close to this years and even that spring was 4 degrees cooler than this year.
In fact, this spring to this point is ranked as the 2nd warmest since 1881, surpassed only by the remarkably warm spring in 1910. That year the average temperature was nearly 5 degrees warmer than this year. As we know, the weather changes quickly in this area, but for now, we are in the middle of the warmest spring in 100 years.
Our first 50 degree high of the year occurred on March 21, this was very close to the long-term average of March 18 for such an occurrence. Our first 60 degree day was on March 29, also, quite close to the long-term average of April 3. Our next milestone was recorded on Wednesday, April 14, when the high temperature at Hector Int’l reached 76 degrees. As was the case with our first 50 and 60 degree day, this was also very close to the long-term average.
Our average first 70 degree day of the year is April 18. The earliest recorded day with a high of 70 degrees or greater was on March 18, 1910 when the high temperature hit 76 degrees (two days later the high was 80 degrees) and the latest occurrence of the first 70 degree day was on May 28, 1907. If you are curious, our average first 80 degree high of the season is May 6.
On Tuesday, Fargo Moorhead recorded the first measurable precipitation since March 15. That was a total of 28 straight days without measurable rain or snow. Although there was no measurable precipitation during this stretch, there were five days with a trace of either rain or snow. Although all five events were brief, nevertheless, there was some precipitation.
I make this distinction because in the past we have gone through slightly longer stretches with no precipitation, not even a sprinkle or a flurry. The longest perfectly dry stretch was 30 days set from September 12 through October 11, 1892. 29 days without precipitation was achieved in the fall of 1903 and during January, 1885.
The most recent stretch longer than what occurred recently with only a trace of precipitation was a period from October 29 through December 13, 1999, a period of 45 days with only a few brief flurries observed.
The ice on area lakes generally went out on April 1 or 2 across much of west central Minnesota. Cormorant, Sallie and Detroit Lakes, according to the State Climatologist’s office in St. Paul, were considered ice free on April 2. Otter Tail and Battle Lakes also were reported ice free on that date. This was three to four weeks earlier than last year when many of these lakes were ice covered until April 23 or later.
Around Bemidji, both Lake Bemidji and Itasca set records for the earliest ice-out dates with Itasca going ice free on April 3 and Bemidji on April 6. As with all such records, they need to be taken in the context of the length of record, as most lakes only have 50 to 75 years of trustworthy data.
Probably the year with the earliest ice out dates in this area was in 1910 which was by far the warmest March since 1881 and the lakes with records that far back confirm that suspicion.
Our recent stretch of mild weather has the trees beginning to bud out, some south facing tulips already in bloom and the lakes in Becker and Otter Tail County free of ice. This of course has many people itching to start planting their gardens. The record for the earliest last frost of the Spring is April 17 that occurred just three years ago in 2007 and the latest occurring on the Summer Solstice, June 20, 1969.
Since 1881, 89 percent of the years had the last frost on or after May 1 with the average date being May 14 in Fargo Moorhead. That means that our average last frost is still nearly five weeks away. In fact, our average last day with a low in the teens was just a few days ago on April 6. Eventually we will all need to roll the dice and plant knowing our springs are fickle, but waiting a couple more weeks would be prudent.
The Arctic sea ice maximum appears to have occurred on March 31. Usually the maximum observed sea ice coverage in the Arctic maxes out in early to mid March, but colder than average conditions in combination with favorable wind allowed the ice to expand through the end of the month. This was the latest date for the maximum Arctic sea ice extent since the start of satellite records in 1979. At maximum, ice covered approximately 5.9 million square miles of the Arctic which is slightly below the average maximum extent.
It was principally areas near Newfoundland in northeast Canada that had less ice than normal that attributed to the season finishing below average. Although the season finished slightly below the average, it was the third straight winter with Arctic sea ice growth since the widely publicized minimums in 2006 and 2007. Research has concluded that changes in wind patterns attributed to most of the sea loss and recent pattern changes are allowing for the expansion of the sea ice once again.
Here is sea ice images from 2010 and 1980:
March finished with an average temperature of 35.4 degrees which is 8.2 degrees above the long-term average. That placed last month as the 4th warmest March since 1881 and the warmest March since 2000 which now ranks as the 5th warmest. The warmest March on record was back in 1910 when the average temperature was 40.9 degrees which is nearly five degrees warmer than any other recorded March.
The average long-term daily low temperature in March is 19.0 degrees, but last month the average was 28.2 degrees which ranked last month as the 3rd warmest for average low temperatures. The average high last month was 42.6 degrees with the average being 35.3 degrees which ranked it as the 13th warmest for average daily high temperatures. March 2010, finished with 1.42 inches of rain and only a trace of snow. That is 0.24 inches above average. Almost all of that rain was from one storm system from March 7-11.