This past Tuesday at 3:11 AM the temperature at Hector
International briefly dropped down to 32 degrees.  That technically was a frost and the growing
season clock was therefore reset to May 27 from the previous last frost that
had occurred on May 21. 

That brief
period at 32 degrees has in turn made this year the latest frost recorded
officially in Fargo Moorhead since 1969. 
Some locations have recorded a frost in June as recently as 2004 and
1998, but not locally.  Back in 1969 the
last frost of the season occurred on June 20, around the summer solstice, so it
was very late that year, although, May 20 was the previous last freezing
temperature before the airport hit 30 degrees on that chilly June morning.  

Last year our last frost was in late April,
very early, this year late May, taken together they would balance out near our
average last frost date of May 14.

Memorial Day weekend is of course the
traditional start of the summer season. So what does the upcoming summer
hold for this area?

I would join with the Climate
Prediction Center
in not having a good sense of precipitation trends for our area, but the odds
are that western North Dakota
will remain in drought conditions.

An interesting question came into the weather center this
week; "This is something my grandmother used to swear by, and also my parents;
that in spring and fall the night of a full moon is more likely to have temps
drop below freezing. I have never done anything to prove this one way or
the other, but last night sure was a full moon, and it sure did freeze in a lot
of places! Do you guys have any hard evidence on this?"

The answer is there is no correlation between
the moon phase and frost. The thing is, frost tends to only form on clear
nights in the late spring or early autumn seasons, so the clear sky of course
gives people notice of the moon be it a full moon, quarter moon, gibbous moon
or waning moon, it doesn’t matter, it is the clear sky that is allowing for
cooler temps, not the moon phase.

Memorial Day weekends can be extremely fickle for weather in
this area. Some years like 1988 were
very hot with average high temperatures of 90 degrees for the three day
weekend. Even as close as two years ago
we averaged 87 degrees for the three days high temperature with one day at 95
degrees.

But if you are like me, you
tend to remember the really bad ones, like 2004, when it rained during parts of
all three days and the weekend total rainfall was 2.30 inches. The one Memorial Day I will never forget was the
one in 1992. It was cold in Fargo, as a matter of fact, the coldest Memorial Day
weekend of the past 30 years locally, but at that time I was living in Mankato, Minnesota.

Not only was it cold there, it snowed, the
latest measurable snowfall ever recorded in that area. Anywhere from 1-3 inches fell on Memorial Day
1992 in southern Minnesota. BRRR.

May has been a cruel month most of this decade.  If you include this year, we have seen five
out of the last seven Mays finish below average, many of them like this years
May, well below average. 

May 2002 was
the coldest of all with temperatures that month finishing more than six degrees
below average.  As a reference, this
month so far has been averaging a little over four degrees below the long term
average.   Back in 2002 we saw three straight days (17th-19th)
with temperatures in the 20s with two of those setting record lows, a few days
later on the 24^th of May the temperature dropped to 26 which tied a
record low. 

After that, May 2002 turned
warm and sunny and spring was
skipped and summer weather arrived almost instantly.  So although this has been a lousy spring, the
odds favor a turn around, and like 2002, it could happen very quickly.

The first half of May was not only cool locally, but
throughout much of the lower 48 states. Ohio, south Texas
and a portion of the southeastern states were the only areas that have seen
above average temperatures so far this month. So in other words, about three-fourths of the
country has been seasonally cool.

Our area
had the largest anomaly of below average temperatures of any where in the
country and when you combined that with the fact we are naturally one of the
coldest areas anyway, it was indeed a chilly first half of May. Although temperatures have rebounded to more
seasonal levels the last few days, it will take quite a turnaround for this
month to finish at or above average.

This stretch of below average temperature
started in late November and has now continued for six months. This cool
pattern will change eventually it is just a matter of when.

The cool, and in many places wet weather
recently has brought frustration to anyone trying to get things planted this
spring.  The most asked question of me lately has been is it safe to
plant yet?  

Considering how this spring has been going, patience will probably be a good
rule of thumb for a while longer.  

Phenology is the study of the timing of natural
events.  For instance, what day the trees leaf out, flowers bloom or when
a certain bird species is first seen in the spring. 

The way my trees look this week, it will probably be a
repeat of 2004 in my yard.

Courtesy of the Minnesota Climatology Working Group in Saint
Paul, a few Minnesota
fishing opener climate highlights:

Minnesota‘s
fishing opener weather is typified by partly cloudy to cloudy skies. Three out
of four years are free of measurable precipitation. A trace of snow has been reported
in northern Minnesota
on at least four of the last 56 fishing openers. On at least three occasions,
some lakes were still frozen for the opener (as of this writing, this year may
make that four).

Opening day temperatures have started as low as 24 degrees at International Falls
(1996, 2004), with freezing temperatures possible even in Minneapolis (31 degrees in 1979).

On the warm
side, Saint Cloud saw 92 degrees in 1987, and International Falls reached 88 in 1977.  This year looks quite cool with rain possible,
mainly in the southern half of the state.  

April 2008 will go down into the record books as a snowy and
cold month.  Fargo Moorhead received 16.9
inches of snow last month which was the second snowiest April on record.  Some parts of west central Minnesota had between two and three feet of
snow in April, with isolated spots reporting nearly 50 inches of snow.  So it will be an April to remember for the
heavy snow falling in the area.  

The moisture
content of the snow in combination with a few rain showers last month contained
2.33 inches of liquid which is nearly one inch above average.  

Of course you can not get all that snow this
time of year unless temperatures are below average and last month finished 2.6
degrees below the long term average. 
That made April the fifth month in a row with below average temperatures. 

It was also the first April since 1997
without a 70 degree high temperature.

More on the April Snow in the area can be found here:

http://www.crh.noaa.gov/crnews/display_story.php?wfo=fgf&storyid=14460&source=0