Record Breaking Late Season Snowstorm of April 23rd-25th 2005
With such an exceptionally variable and stormy winter it was actually fitting that the Winter of 2004-05 went out with a bang and not a whimper. If the persistent cold and snow during March wasn't enough to extend an already lengthy winter, Mother Nature really gave the inhabitants of Southeast Lower Michigan a sucker punch late in April.
A very nice stretch of sunny, dry (actually too dry) weather commenced late March into the first three weeks of April. This beautiful early spring weather reached a climax on the 19th when record highs were attained at all three climate stations (DTW/FNT/MBS). Ironically, not only did all three cities have record highs but it also was with the same temperature, 83 degrees. After the 19th, however, the weather was all downhill, accelerating big-time by the weekend. A series of cold fronts pushed south across the Michigan from the 20th to the 23rd, dropping temperatures some 40-50 degrees by the weekend /23-24th/!
An intense low pressure developed along an arctic cold front over the Upper Ohio Valley Saturday into Sunday and actually backed westward into the Eastern Lower Great Lakes (over Southwest Ontario - central pressure about 29.25" /986 MB/). This storm brought the worse late April weather seen in these parts in several decades. Snowfalls from the storm ranged wildly from a trace to as much as 16.5" with the heaviest falling across the highland areas from central Oakland County northeast into the Thumb Region (around Bad Axe). This very late snowstorm was the "icing on the cake" so to speak on what already had been a very snowy season. More information is available on April snows and total snowfall amounts from this storm. Incredibly, the May 9th, 1923 snowstorm which contained similar snow depths is over two weeks later!
The phasing of upper level jet steams, resulting in intensifying low pressure systems over Lower or Eastern Great Lakes have been responsible for some of our worst snowstorms; as evidenced by the above and following...
Snowstorm of May 9th, 1923
Not since records have been kept in Southeast Lower Michigan (Detroit as far back as 1870), has the snowstorm of May 9th in 1923 been equaled in season lateness and magnitude. A strong cold front, of Arctic origin, pushed across Southeast Michigan on the afternoon of the 8th, creating scattered thunder- storms. The strength of the front was quite evident in Detroit. The temperature plummeted from a near normal reading of 62 degrees at 100 pm to a winter like one of 34 degrees by 600 pm. Behind the front, the stage was set for some startling weather developments for the month of May...even in Southeast Lower Michigan. Rain mixed with snow fell across the area during the evening of the 8th. Detroit received an estimated inch of snow which melted on the ground before ending by midnight. On the morning of the 9th, a low pressure area developed along the front in northwest Ohio and moved over Lake Erie during the afternoon. The developing low pulled warmer, moist air north from the Ohio Valley and mixed with the unseasonably cold air mass over Southeast Lower Michigan. As a result, a heavy, wet snow began falling during the forenoon hours and continued through the afternoon. Arguably, one of the most astonishing things (and there were several) about the mid-spring snowstorm was that the bulk of the snow fell during the time of day which is normally considered "the heat of the day" or "afternoon heating" when normal highs of the day are attained. The afternoon temperatures never budged from the lower 30s (31-33) and was accompanied by a stiff northwest wind, averaging 15 to 25 mph. Keep in mind, the normal or average high for May 9th is 67...some 35 degrees warmer! The snow ended by the evening in Detroit and at 800 pm, six inches was reported on the ground. The story was even more fantastic as one traveled west and north of Detroit across Southeast Lower Michigan. Generally, six to nine inches fell west to the Ann Arbor area, northwest through Howell, north across Pontiac and northeast up to Port Huron. Even more incredible, snow depths of around a foot were reported at Flint and Lansing north into the Saginaw Valley. Widespread damage was reported to trees, power lines (many had a two inch circumference of snow hanging on them) and telephone poles, especially in the Saginaw Valley. Even so, economic damage was surprisingly small, especially to spring vegetation. Evidently, the earlier spring weather had been abnormally cold and this led to a late green up. Substantial damage from the cold to vegetation and crops was actually averted due to the insulation affect of the heavy, wet snow. Many May snow records (amounts and lateness in the season) were shattered and stand firm to this day over Southeast Lower Michigan. By the next morning (10th), much of the snow had melted and by the evening, it was just a memory. The official high in Detroit on the 9th was 39, but that occurred just after midnight, before the storm. The low was 31, which occurred in the afternoon during the storm, giving a mean of 35 for the day and 21 degrees below the normal of 56. Other May record snowfalls in Detroit pale in comparison. In 1912, 1.5 inches fell on May 13th for the second highest amount and the latest snow actually occurred the last day of the month, May 31st, 1910 with a trace. So, the next time you think it's too cold for this late in spring or we can't possibly have a measurable snowfall in May across Southeast Lower Michigan, you might want to THINK about it again (or maybe not).
Unbelievable Snow of May 21-22, 1883
Since this was so long ago; it was questioned at one time if it really occurred and
if the snow amounts were legit or not. While at NWS, DTX, I was very curious
myself and dug back into the archaic records of nearly 132 years ago now,
to investigate the authenticity of such occurrence. Not only was there snowfall
recorded between 7PM EST May 21-7AM EST May 22, 1883 but it was impressive
amounts being so very late in the spring!
Snow began to accumulate during the evening hours of the 21st, leaving a snowfall
of 2.3" by midnight (snowfall, not snow depth). The snow continued from midnight
until the early morning hours of the 22nd, leaving an additional 2.7" snowfall
recorded by 7AM the next morning. Therefore, there was a total of 5.0" of snowfall
during that 12 hour period - the entire event. However; I don't ever recall seeing
a 5" snow depth on the ground the morning of the 22nd, as part of the snow melted
as it fell. Record lows of 32 degrees were reported both days, the evening of the
21st and early morning of the 22nd, mainly during the snowfall. In addition, a record
low maximum of just 41 degrees was recorded on the 22nd! Normal highs for that late
in May are lower 70s while lows in the lower 50s! Therefore; the temperature average
for May 22nd, 1883 was 37 degrees or 25 degrees below normal /62/, extraordinary for any
winter month - let alone late May!
The Monthly Weather Review quotes Detroit as having snow on the 21st-22nd though
the amounts were not listed. I was able to pull up the daily morning weather maps
from May 21, 1883 and May 22, 1883; See for yourself, this storm along with its
development again bring up the Ohio Valley/Eastern Lakes Low development that
matures over the East and Northeast part of the country. This type of pattern is
reminiscent of many of our major snowstorms, including the rare late season ones
discussed here.
SURFACE MAP OF 5/21/1883 - 7AM
SURFACE MAP OF 5/21/1883 /Cropped and analyzed-WRD/
The central pressure of the low had deepened close to 29.30"/992 MB /lowest
pressure analyzed 29.34 IN outside of the center/ moving into West Virginia
the morning of the 21st. The sub 40 degree temperature isotherm is entered in a
blue dashed line.
SURFACE MAP OF 5/22/1883 - 7AM
The central pressure of the low remained close to 29.40"/995 MB /lowest pressure
analyzed 29.47 IN outside of the center/ in the Washington DC area the morning
of the 22nd. The sub 40 degree temperature isotherm is entered in a blue dashed
line.
Of course, the 500 MB upper air map was non existent for the date but can be
extrapolated and it must have been a mighty cold upper low to support that kind
of storm and snowfall so far south, a little better than a week before June.
Making weather fun while we all learn,
Bill Deedler -SEMI_WeatherHistorian
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