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Up and Down Temperatures This Week

There are two chances for thunderstorms this week and temperatures will range from the 90s to the 50s. For today, the best chance for Showers and Thunderstorms will be this morning, although a shower could linger into the afternoon. Mostly Sunny skies are forecast on Tuesday with highs in the lower-80s. Wednesday we need to watch closely. Strong winds will blow in very warm air, which will result in high temperatures of 90° to 95°. Additionally, Showers and Thunderstorms are likely with heavy rain. Some storms may also become severe. A cold front will drop temperatures into the lower-80s for highs on Thursday and Friday, which is also when low temperatures in the 50s are likely Friday and Saturday morning. The heat then builds back in with upper-80s to near 90° favored for highs this weekend.




1,000 Year Flood


A Catastrophic Flash Flooding Event occurred last week on July 25th and 26th in St. Louis, MO. Interestingly, it was so incredibly extreme, that the flooding is being considered a 1 in 1,000 year event or a 1 in 1,000 year flood. Although this may seem like a term that would be used to describe only a rare event or to hype something up in the media, that simply isn’t the case this time around. True, sometimes you do hear the term floating around ahead of a potential flooding event that is being forecasted as a possible 1 in 1,000 year event, but in reality, because floods of this magnitude are so rare, forecasting them accurately is simply not possible. The Flash Flooding that occurred in St. Louis this past week statistically had a 0.1% chance of happening in any given year. During a 24-hour period, the official observing site in St. Louis recorded 9.04” of rain, which not only set an all-time daily record, but also provided more rain than would typically fall in both June and July combined. What is another big takeaway as to why this is being classified as a 1 in 1,000 Year Flood? In just 6 hours, 7.68” of rain was measured, which quite literally has less than a 1 in 1,000 (<0.1%) chance of occurring in any given year.


Furthermore, the localized scenario of this event was also fascinating. This is a good time to explain what we mean by “localized” or “locally higher amounts possible” when communicating forecasts to you. First of all, forecasting for your backyard is not possible. Forecasting is done by determining a certain radius within any given location and predicting the probability of something happening within that mathematical area. For example, let’s take a 25-mile radius around Mount Pleasant and draw a circle. If we say 1” to 2” of rain is likely within this area, that means that within that 25-mile radius (within the circle) the most likely outcome is 1” to 2” of rain. However, we often follow that up by saying that “locally higher amounts are possible” or “some areas may miss out and see less than 1”. This means something on a very small scale, perhaps on the order of tenths of a mile, higher or lower rainfall totals may occur, but forecasting down to that specific square tenth of a mile is not possible. Therefore, we communicate that risk to the forecast by telling you what is possible, even though we can’t tell you exactly what will happen in your backyard.


Now back to what I was referring to by saying that the St. Louis Flash Flooding was localized. The highest rainfall totals were reports between 12” and 14” northwest of St. Louis. St. Peters is one of these locations to record 1 foot or more of rain. If you drive just 30 miles south of St. Peters, the rainfall totals were as low as just 0.5”. That is a significant difference over a relatively short distance. To put that in perspective locally, Harrison is 30 miles north of Mount Pleasant in Clare County. Imagine being in Mount Pleasant and receiving 12” of rain and then somehow being able to drive your car north on US-127 and you arrive in Harrison about 25 to 30 minutes later. There, the rainfall total is only a half inch and no big deal. That’s a relatively short distance to travel and go from catastrophic conditions to no problem at all.


But wait…there’s more. As if only one major flooding event wasn’t enough. How about 2? This isn’t just another flood, though. It’s a second 1 in 1,000 year flood during the same week. While the first one we just covered occurred in the St. Louis area, this second one occurred in eastern Kentucky. 8” to 10” of rain was measured, which resulted in catastrophic flash flooding. 2 major and rare floods in one week. That is quite a story to talk about. Many lives have been altered forever along with a major loss of property and belongings.


Mt. Pleasant Almanac for This Week:


Almanac Information is a way to look at normal and record high and low temperatures for this time of year. The normal temperatures are based on the 30-year average high and low for that date between 1991 and 2020. For example, if you take the high temperature for every August 1st between 1991 and 2020 and calculate the average of all 30 values, the result would be 83°. Therefore, the normal high for today is 83°. Record high and low temperature data goes back to 1895. Sunrise and sunset data is also provided. All information is valid for Mount Pleasant.


August 1st:

Normal High/Low: 83°/61°

Record High: 99° 2006

Record Low: 38° 1927

Sunrise: 6:29AM

Sunset: 9:02PM


August 2nd:

Normal High/Low: 83°/60°

Record High: 100° 1988

Record Low: 40° 1920

Sunrise: 6:30AM

Sunset: 9:01PM


August 3rd:

Normal High/Low: 83°/60°

Record High: 98° 1944

Record Low: 40° 1918

Sunrise: 6:31AM

Sunset: 8:59PM


August 4th:

Normal High/Low: 83°/60°

Record High: 98° 1988

Record Low: 40° 1912

Sunrise: 6:32AM

Sunset: 8:58PM


August 5th:

Normal High/Low: 83°/60°

Record High: 99° 1947

Record Low: 39° 1907

Sunrise: 6:33AM

Sunset: 8:57PM


August 6th:

Normal High/Low: 83°/60°

Record High: 108° 1918

Record Low: 38° 1907

Sunrise: 6:34AM

Sunset: 8:55PM


August 7th:

Normal High/Low: 83°/60°

Record High: 101° 1918

Record Low: 42° 1927

Sunrise: 6:35AM

Sunset: 8:54PM


August 8th:

Normal High/Low: 83°/60°

Record High: 99° 2001

Record Low: 41° 1927

Sunrise: 6:36AM

Sunset: 8:53PM


Mid-Mitten Weather View’s Mission is to serve people by providing timely information to help keep you safe and make decisions based on the weather. We are passionate about educating both our forecasters and our followers about how weather forecasting works and how we can be best prepared when impactful weather threatens. Our team consists of both CMU alumni degreed meteorologists and current student forecasters from the University. For daily updates, we welcome you to check out our Facebook Page! We look forward to catching you back here next week for another weekly 7-Day forecast update.


-Weather Forecast by CMU Student Forecaster Isaac Cleland

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