Where’s the Flood?

In the space of thirteen days, from May 6 to May 18, Fargo Moorhead’s annual precipitation total to the date went from the 17th driest on record to the 15th wettest .  The 5.82 inches of rain that fell those thirteen days alone would rank in 8th place on the list of wettest Mays.  And yet there was hardly any river flooding in the entire region.  Sure there has been some minor lowland flooding in the typical flood prone areas, the sort of flooding that is common after heavy rain.  But nowhere in our region has there been any of the significant flooding one would expect following such a rain.  Most of the fields that had standing water for a few days have dried nicely, suggesting additional water storage capacity if needed.  We can thank the fall-winter-early spring drought for this.        Meteorologist John Wheeler

Rain and Heavy Rain

Rainfall and heavy rainfall go together.  That is, when there is a pattern of above-average and more frequent rainfall, it is also more likely that there will be a downpour.  Warm weather and heavy rainfall also go together.  When the atmosphere is warmer, there is more capacity to hold moisture in the air, which increases the potential for downpours.  As the average temperature in our region has risen since the middle of the 1900s, so has the frequency of heavy rains.  Also, as the average annual precipitation began to rise in the 1990s, the downpours have been increasing.  The flooding problem across our region the past 20 years can be tied to both of these trends.  The future of flooding in our region is likely going to be tied to both of these trends.  Additional warming appears likely but a further increase in annual precipitation is probably less likely.   Meteorologist John Wheeler

Rising Seas?

Although the interior of the Antarctic continent is getting colder, one of the most rapidly warming locations on Earth the past few decades is along the Antarctic Peninsula.  An ice shelf known as Larsen C, the fourth largest ice shelf in the world at more than 20,000 square miles, adjoins the Antarctic Peninsula and has been discovered to be melting at a rapid rate due to the warmer air temperatures and the warmer seas underneath.  A research team from the British Antarctic Survey has reported a growing crack in the shelf which could cause it to break up some time in the next 100 years.  This would not lead directly to a rise in sea levels because this ice is already floating in the ocean.  However, if the region continues to warm, the loss of the ice shelf could allow glaciers presently land locked to melt into the ocean faster.  Sea-level rise is one of the greatest concerns associated with Global Warming.   John Wheeler

Drought Beginnings and Endings

 

It was just one week ago that it started raining.  Rain over the seven days since has been plentiful enough to eliminate all concern about it being dry.  It is interesting to note that our weather condition can switch from dry to wet in such a short time.  On the other hand, it cannot switch from wet to dry so quickly.  Of course, it can stop raining tomorrow, but the lingering effects of recent rain will keep the soil soggy and the grass growing for some time.  The winter drought began last September 5.  That was the day after the last heavy rain of 2014.  We were in a drought through the fall because the drier weather caused us no problems.  The drought really began to manifest itself this spring with agriculture’s need for germinating rainfall along with a rash of grass fires.  Now suddenly, all that is over.  I wonder when the next drought will begin.  Tomorrow, perhaps?

Meteorologist John Wheeler

Is Drier the New Average?

All this talk about below average precipitation the past few months begs a discussion on what it means to be average.  The weather is not “supposed” to be average or even near average.  The weather goes from above to below average all the time and sometimes by a lot.  In fact, what we call average is always changing.  Our weather and our climate are not static.  It gets wetter and it gets drier.  It gets warmer and it gets colder.  These things vary day by day, month by month, year by year, century by century, and so on.  In fact, the accepted, so-called “climate normals” are actually the average of the previous complete three decades.  Every ten years, what call “normal” or “average” is adjusted to reflect the latest decade in order to remain current.  For more than 20 years, precipitation has been generally wetter than in the past, creating a new “average.”  Sooner or later, perhaps now, the weather will likely become consistently drier again.

 

Meteorologist John Wheeler

Drought Brings Good With Bad

Since 1993, the weather pattern over the Red River Valley region has been wet.  Dry periods within this time frame have been few and generally brief. Average annual rainfall increased 15-20 per cent starting in 1993.  The weather has been wetter and for a longer period than the dust bowl years were dry.  Eventually this pattern will end but it is not possible to know in advance if the change will take place in another hundred years or if is starting right now.  Weather is difficult that way.  Although drought is hard on our overall economy and water shortages can make life more difficult, drought is a naturally occurring part of nature.  It has a way of rebooting wetlands, leaving them healthier and more productive.  A drought would lower the almost annual flood threat by lowering reservoir levels.  And a drought would lower Devils Lake.   Meteorologist John Wheeler

The Year of the Flood in Media

Floods, not tornadoes, continue to be the weather disaster theme of 2014.  The extra-tropical remnants of Hurricane Odile spreading soaking and occasionally torrential rain across the Desert Southwest is just another example of flooding in the United States this year.  While the flooding has made news, it should be pointed out that the number of floods and the severity of the floods recorded this year are nothing out of the ordinary.  But with the Atlantic hurricane season very quiet and with the number of tornadoes this year well below average, most of the weather coverage in the news has been of flooding.  Probably the most anomalous and significant weather disaster anywhere in the United States this year is the ongoing multiyear drought in southern California.     Meteorologist John Wheeler

 

 

June Wet and Stormy, Kind Of

June was a wet and stormy month.  Rivers are high from Manitoba to Tennessee.  Almost every evening on the national news there is coverage about all the severe storms this summer.  But the national tornado count on the Storm Prediction Center’s Annual Storm Summary web page shows that the last year to have had so few tornadoes through July 1 was 2005.  What about all the rain?  It has been wet but nowhere nearly as wet as it was in 1993.  June was a bad month in the Great Plains and Midwest for storms.  But June was certainly not record bad and it wasn’t really even unusually bad.   Instead, network news is just covering the heck out of stormy weather.  It is riveting and extremely popular.  Weather is good for ratings.  And while the coverage is well-intended and truthful, the viewers should not be persuaded by the sheer volume of storm coverage into thinking this summer is out of the ordinary.   Meteorologist John Wheeler

I Knew It Was Cold Here

An article last week in Nature Climate Change identified the few places around the Northern Hemisphere most prone to extreme weather.  Specifically, the study identified those places most likely to have stalled out large-scale jet stream waves as these are the mechanisms for too much rain, snow, cold, heat, etc.  For cold air anomalies, we are in a bad spot.  It turns out, the eastern half of North America is most vulnerable to long-term cold air outbreaks.  The worst flooding occurs in western Asia.  Drought is most prevalent across central North America, Europe, and central Asia.  Heat waves are most likely over western North America and central Asia.   Meteorologist John Wheeler

Spring in Review

It was a cool and wet spring, which should not come as a surprise.  What may surprise you is that it was neither extremely cold nor extremely wet.  The average temperature in Fargo Moorhead for the months of March through May was 39.7 degrees.  This is 2.3 degrees colder than the average over the past three decades.  March was the most below average of the three months, particularly early March.  The first day of March, the high temperature in Fargo Moorhead was eight below, which had occurred at midnight.  The afternoon high was ten below.  Both March and May were drier than average, but a rainy end to April brought the three spring months up to 0.64 inches above average overall.  Almost half the precipitation during the past three months (2.95 of 6.14 inches) fell over the final seven days in April, causing moderate flooding on the Red River. The river has remained slightly swollen ever since.     Meteorologist John Wheeler