During the past three months, large-scale storm systems (including the snowstorm that struck Minnesota and Wisconsin earlier this month) have been noted for their excessive wintry weather. Throughout the winter, people in media, and just ordinary folks, have been bemoaning the extreme and unrelenting weather.
Now that spring has arrived, people have started to rejoice as cold weather moved northward and warmer air returned. However, in the wake of winter, even wilder weather extremes, severe storms, flooding and even an occasional snowstorm, have wreaked havoc across many parts of the Nation. And, more wild weather swings are underway and on tap. This is NOT surprising. Spring is often the transition season and brings with it lots of weather variability.
Consider weather happenings so far this April (2014). According to the Insurance Council of Texas, severe hailstorms across north Texas on Apr. 3, 2014 reportedly damaged 24,000 vehicles and 12,000 homes. Damage totaled $300 million, making this event the 21st most costly hailstorm in Texas since records began.
A few days later, another storm system brought severe flooding to Alabama. Over the period Apr. 5-7, 2014, especially during the night of Apr. 6-7, torrential rains fell across Alabama. There were widespread reports (and radar indications) of 3 inch or more rainfall totals across the state. Many places logged rains of at least six inches (Fig. 1).
Not surprisingly, small creeks went into flood quickly. Many underpasses, especially in urban centers, were also flooded. News reports indicated that several deep water and flood rescues were made during the early morning hours of Apr. 7.
A few days ago, another storm system moved across the Central U.S. This one brought some dramatic swings in weather across the Central Plains (Fig. 2). Last Saturday’s heat across the High Plains of Kansas and Colorado was quickly replaced by strong northerly winds and some snow. As of early on the evening of Apr. 13, 2014, one to eight inches of snow had fallen across parts of Colorado, mainly in the mountains. According to the National Weather Service, heavy snow falling in Summit County forced the temporary closure of I-70 between Vail Pass and Georgetown.
Across the Central Plains, strong southerly winds ahead of the storm system allowed a high temperature, high moisture air mass, streaming north from the Gulf of Mexico, to help fuel a spate of severe storms. During the three-day period from early on Apr. 12, 2014 to early on Apr. 15, 2014, there were more than 500 severe weather reports (mostly large hail and high winds) across the Central U.S. and parts of the Deep South.
Late on Apr. 13, 2014, tornado and severe thunderstorm watches covered parts of the Southern Plains. Flash flood watches extended from southeastern Iowa into Michigan, across parts of northern New England and across large regions of Alabama and Mississippi.
Ahead of the advancing cold front, red flag warnings covered much of New Mexico and parts of west Texas. Here, high winds and low moisture values (air mass from desert southwest) were creating a high fire danger.
Behind the cold front, unseasonably cold air was spilling southward. Freeze and hard freeze warnings were in effect for much of Kansas and Oklahoma Sunday night (affecting some of the same areas that experienced severe weather earlier in the day).
At Tulsa, OK, for example, last Sunday’s high temperature of 83 degrees (on southerly winds of nearly 30 miles per hour and gusts to more than 40 miles per hour) was replaced on Monday by temperatures only reaching 50 degrees (along with comparably strong northwesterly winds). On Tuesday morning, the temperature dropped to 30 degrees in Tulsa.
High temperature readings barely entered the lower 60’s in Tulsa on Tuesday; the high is expected to be near 70 degrees at this time of year.
Perhaps the temperature graphic produced by the NWS office in Amarillo, TX best portrays the wild temperature swings (Fig. 3). From record/near record highs on Saturday, the temperature graph showcased possible record low high temperatures by Monday. On both Monday and Tuesday mornings, the temperature at Amarillo dropped into the 20’s.
The chill down has spread to the East Coast and the Deep South. Freeze warnings were in effect for much of the southeast quarter of the nation this Wednesday morning (Fig. 4). The only areas escaping the wintry cold were expected to be coastal areas from the Mid-Atlantic to Gulf Coast, including, of course, the entire Florida peninsula.
Thereafter, the ongoing pattern locks in place (Fig. 5). For the next two weeks, one month and three months, temperatures across the eastern half of the Nation are expected to range from slightly below to well-below average (with obvious variability in both time and space). Rainfall will be near to slightly above average, especially along the northern tier.
In the west, look for above average warmth to persist. Rainfall will be average to below average. This spells a continuation or intensification of drought conditions from Oregon across the Desert Southwest into western Texas and Oklahoma.
© 2014 H. Michael Mogil
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