September Cool To Mid- September Warmth - Part II

Let's go back to the first 10 days of the month. Temperatures were below normal. We had a 5 day stretch of highs in the 60s/70s and lows in the 40s in spots. Then the pattern flipped. Starting on 9/11, the temperatures reached 80 degrees. The first of 12 straight days. 

To have 

Here is an animation of the upper level pattern starting September 6th.  Cool colors are low pressure.  Warmer colors are high pressure. Notice the cool colors over the Great Lakes at the start. See how the ridge of high pressure replaced it. It developed over western Canada, moved east and deepened between Hudson Bay and the Great Lakes. Low pressure stalled in the western US. Southern systems undercut the big ridge as indicated by the cool colors across southern states.

The overall temperatures vs normal starting September 6th:

The difference in average temperature from September 1-10 and September 11-20 was huge.  I compared each year to see where 2024's September temperature flip ranked.  Sure enough, the temperature change was the second biggest jump ever!

Here is the last 30 years for comparison. 1985 is on the left.  2024 is on the right.  2017 had the biggest jump.

The warmth (80 straight days with highs in the 80s) ended up lasting 12 days.  Here are the years that had similar stretches of September warmth.

What was unusual about this year's 80 degree stretch was the OVERALL lack of high humidity.

Here are the daily temperatures (line) in the years above during each stretch with the average dew point for each year:

You can better see the differences when you plot the daily dew points in each year. Notice that this year was lower overall.

Here is a plot of the daily dew points for each year in September since the early 1970s. Cool colors indicate comfortable dew points. Any day with a dew point UNDER 60 is shown with a blue color. Right side is the second half of the month. Notice the frequency of less humid days is much higher after September 15th (black line).

Our First Rain in 17 Days! - Part I

The first rain since September 6th moved through late yesterday and earlier today. 

Radar loop above is from 5PM Sunday, September 22 through 12:30PM Monday September 23.

The top amounts were around 1/4" with most well under 0.1".  A small bulls-eye in southern Cuyahoga county from late evening showers on the 22nd.

Here is the total rainfall between September 7 and September 21.

This was the NE Ohio rainfall on September 6th. I superimposed the drought monitor information over the rainfall contour for reference.

Rainfall vs normal between September 7th and the 21st:

Midwest was just as dry.

Even if you extend this map out to early August, rainfall has been well below normal.

Early summer (June 1 to Auguts 1) was well above normal in the midwest/Central US. Ohio was overall below normal since June 1.

The frequency of storms was also way down over the last 3 weeks. Lightning strikes were scarce across northern Ohio.

Last year was September storms were a bit more prevalent.

Relief Pitching FIP and Team Wins

San Diego, Atlanta and Cleveland have the best relief pitching in baseball. 

Here are the top ten teams Relief Pitching xFIP thus far:

1. San Diego  3.65
2. Atlanta   3.66
3. Cleveland   3.68
4. San Francisco   3.75
5. Philadelphia   3.78
6. NY Mets   3.90
7. Minnesota   3.92
8. Seattle   3.94
9. Miami   3.98
10. Baltimore   4.00

Remember that FIP is a stat that estimates a pitcher's run prevention independent of defense. It's based on only Strikeout, walks, hit by pitches and home runs allowed. xFIP finds a pitcher's FIP, but it uses projected home-run rate instead of actual home runs allowed. The home run rate is determined by that season's league average HR/FB rate.  FIP uses the ERA scale. More can be found about the FIP and xFIP calculations on Fangraphs HERE

Since we don't have xFIP prior to 2002, I used overall relief pitching FIP and compared team win total for each team since 1997.

FIP is on the y-axis. Each season in the x-axis. The higher the FIP on the y-axis (using the ERA scale) the worse the relief pitching.

Red dots below are the teams with 95 wins in each season since 1997. Notice that only 26 teams of the 119 teams who had 95 wins since 1997 had relief pitching FIPs higher than 4.00.  That's only. 21.8%.  

Of course many things can happen in the playoffs.  For fun, how many of these 95+ win teams since 1997 won the World Series? 

Here are the other World Series winners who didn't win 95 games.

The top 5 worst Relief Pitching FIP World Series winners:

2023  Texas Rangers

2010  San Francisco Giants

2006  St. Louis Cardinals

2000 New York Yankees

1997 Florida Marlins

Each of these teams made up for their relief pitching deficiencies with either top 10 starting pitching or top ten ability to create and score runs.

Is Late August/Early September Heat More Frequent Nowadays?

Today the temperatures reached the lower and mid 90s across not only Ohio but much of the lower Great Lakes and Ohio Valley. The question of whether or not late season heat is becoming more frequent in northern Ohio always surfaces during heat like this.  

High temperatures August 27th:

Heat Index reading on August 27th:

So how do we answer this question?  First what time period are we looking at when we say "late August/early September"?  I like to use the last week of August and first week of September. A fourteen day period that is a decent duration sample size.

August 25 to September 7

What about temperature?  First, let's take look how many instances each year the high temperatures reach 90 degrees or higher during this 14 day period? (Given the forecast we could conceivable hit 90° four times by the end of the week).

Contrary to some of our recollections, its been 6 years since we had a late August stretch of 90+ similar to this year.  This actually occurred the most frequently in the 1950s. The early 2000s are a close second with high occurrences in 2010, 2012, 2016 and 2018.  With the exception of a few years like 1973, 1983, 1991 and 1993 it rarely happened in the 1960s, 70s, 80s and 1990s.  

What was interesting about the late August/early September of 1953 period was that we were above 90 degrees eleven of the fourteen days. 

The top number is the high temperature. The bottom number is the highest heat index that day.  Notice the extreme humidity didn't accompany the heat initially. In fact, dew points were very dry the first 6 days of that stretch from August 25 through the 30th. It wasn't until later in the period -- day 7 of the 11 day stretch -- that the heat index rose above 100° for 4 straight days.

Now compare 1953 and its 10 days above 90° to the 7 day stretch in 2018.

What about the overall average high temperatures during this 14 day period.  Are there any changes locally?  Here is a look each year since 1980. 2016 and 2018 were well above normal in high temperatures as was 2010 and 2012.  

Were these warm, late season stretches just relegated to northern Ohio?

Notice that most of these late season hot periods were centered over the Great Lakes, Ohio Valley and portions of New England and eastern Canada while the western US experiences well below normal temperatures.  Below are the temperatures above normal (warm colors) and below normal (cool colors) across the US and Canada.

The bottom line is that long hot stretches don't happen every year in late August/early September like many remember. 

  

ALL Ohio Tornadoes - Monthly Counts Since 1950

Numbers are through August 15 of 2024:

What is A Drought? How Does Summer 2024 Compare to Others?

Rainfall over the last 24 hours as of this writing (August 3) has been the most widespread in quite some time across Ohio and surrounding states. We needed it!

Yet each summer, it seems as if we go through the same process:  Rain at the beginning in May and early June with a gradual drying out with limited rain across northern Ohio by late June/July and into August. The grass gets brown. We mow every two weeks or longer versus every other day in early May. Most of us will mix in the word "drought" in  everyday conversation describing the conditions as we exclaim "this happens every summer."  At least that's how we perceive it. But is this really the case?  What does the data show?

First what is the definition of a "drought"?

Drought is generally defined as "a deficiency of precipitation over an extended period of time" resulting in a water shortage. This is per the National Integrated Drought Information System on drought.gov (a great resource). However drought can mean different things to different regions. If you are a farmer, a drought means below normal rainfall resulting in damage to crops. So not enough water means low crop yield for the season. 

Scientifically, drought can be measured through comparing precipitation departures over a period of time along with soil moisture, evaporation, temperatures among others.  A great way to compare year to year is to use the US Drought Monitor.  This is a blend of around a dozen different variables including the ones listed above. This is combined along with potential drought impacts and other expert insight. 

The US Drought Monitor index is on a scale of zero to four. One being low on the drought scale up to four meaning highly extreme drought conditions as defined above.

Just looking at precipitation changes since April you can see how the conditions in parts of Ohio/southern Ohio, the Ohio Valley and into the Carolinas/SE US have dried out significantly.

Interestingly, the corn belt and most of the Great Lakes, conditions have not been dry at all. In fact, soil moisture has been well above normal.

Back to the original question. What about the comment that we are always in a drought every summer here in northern Ohio.  Is this true?

Look at the Drought Monitor history for Ohio as a whole. Here are the years since 2000 (data only goes back that far) with portions of the state in at least a D2 drought with areal percentages.  The last time ANY part of Ohio was under a D2 drought was 2016.

Can we go back further?  Absolutely, but we need to use a different set of data.  It's called the Palmer Drought Severity Index. This data goes back more than 100 years. The PDSI is good at determining long term drought using temperature and precipitation data to estimate dryness.  So a +4 shows extremely wet conditions. A -4 is extremely dry. 

Here are the PDSI conditions across the US as of late July:

Notice that the conditions across Ohio are not as severe when looking at the LONG TERM drought conditions.

Let's go back in time just looking at the summer months of June, July and August combined. To do this, we can examine specific climate divisions versus state wide conditions. Here in northern Ohio, we have four climate divisions that encompasses our viewing area. Two, three, six and seven.

I highlighted some of the memorable drought summers for Division two. The dust bowl years of the 1930s, the early 1950s and 1960s were long periods with summer drought. Of course 1988, 1991 and the early 2000s also featured very dry summers.

Here is climate division 3:

Climate division 6:

Climate division 7:

As you can see, there are much drier periods over the last 100 years across northern Ohio.  There are also (green bars on these charts) with above normal summer wet conditions.  In fact in the last 30 years, the summers with above normal wet conditions have outnumbered the abnormally dry ones. 

Number of Abnormally Dry summers (JJA) Since 1995

Climate Division 2:  9 of 30 summers

Climate Division 3:  12 of 30 summers

Climate Division 6:  9 of 30 summers

Climate Division 7:  9 of 30 summers

While our lawns dry out each summer to some degree, is it true that every summer or even most summers in northern Ohio we end up with drought conditions?  Not even close