Atlantic Tropical Update
As Hurricane Florence barrels through the Atlantic toward the United States, it is easy to lose perspective on what the norm is for hurricane activity this time of year. That being said, it’s certainly not out of the ordinary to hear about a large number of storms churning out in the Atlantic Ocean in September. After all, it is the month of peak hurricane activity, which statistically occurs on September 10th.
What Are The Dog Days Of Summer?
We have all heard the phrase before, but what exactly are the dog days of summer? It's normally used to describe those hazy, hot and humid summer days (like this week). However, you may be wondering how such a unique phrase got started...and does it really have anything to do with dogs?
July 2018: Warm & Dry in the Midwest
The warmth we saw in May and June continued as a stretch of hot and very muggy conditions into the first week of July. This prolonged stretch of weather was a result of a large ridge in the jet stream that was firmly planted over the Ohio Valley and Northeast, which pushed the jet stream well north into Canada allowing tropical air northward. A generally dry pattern was in place during the first week of the month, with only disorganized thunderstorms that dropped hit and miss rainfall across the Midwest.
July 2018: Quiet, Then Much Like Florida
Whatever heat wave we had at the beginning of July would be a lost memory by the second half of the month. Temperatures would not even really be the defining factor as excessive rainfall made the headlines, shattering records by the third and fourth week. This would all be thanks to a stark pattern shift that would send a plume of tropical weather our way.
Temperature Extremes & Seasonal Lag
We’re well into the summer season, and we’re seeing some of the year’s warmest temperatures in our region. In fact, some of the hottest temperatures ever recorded have occurred in July and early August across the mid-Atlantic and Northeast, as the chart below shows:
June Midwest Summary: Flooding Rains and Intense Heat
Throughout the month of June, Chicago and Rockford saw multiple rounds of flash-flood-inducing heavy rain while numerous stationary fronts sparked sporadic shower and storm activity in the Ohio River Valley. However, regardless of where you were in the Midwest during June, several potent heat waves brought temperatures into the 90s. Summer-time work became difficult when associated heat indices rose over 100 degrees at times throughout the month.
June 2018: A Seasonable Start to Summer
After coming off an unusually warm May, the first month of meteorological summer proved to be rather seasonable. However, much of the Northeast outside of Maryland and parts of southern Pennsylvania dealt with dry conditions. This unfortunately has transpired into a drought across central and northern New England, which is still persisting into July as we speak.
Relative Humidity vs Dewpoint
This summer has had many days of hot and sticky weather. You may have checked on the humidity, only to find it was at a meager 50%. How could the humidity be so low, when it feels so high? The answer: dewpoint!!
Dewpoint is the temperature at which water vapor in the air condenses into liquid water, such as in the form of dew, fog, or possibly rain. The dewpoint is always lower or equal to the air temperature, hence why dew or fog often occurs during the early morning hours, when the air temperatures are typically lowest and the dewpoint highest.
Heat Advisories & Excessive Heat Warnings
During the summer, you may have noticed that the National Weather Service issues a variety of watches, warnings and advisories in order to protect the public from various heat related illnesses…including heat cramps, exhaustion and stroke. However, based on client feedback, sometimes the general public is left in the dark as to what the exact criteria is for these alerts to be issued.
7 Years Ago: The June 2012 Derecho
When called upon to remember a significant weather event within the last 10 years or so, some may bring up a powerful snow storm or blizzard. But for those that were within the path of the June 29, 2012 Derecho, the case is a bit different as that system was one of the top (if not the top) memorable events within the last 15 years or so. This straight-line windstorm, which occurred in the middle of a record heat wave, left millions without power and caused widespread property damage to areas within its path. Here's an idea of what a derecho is: