Good afternoon and happy Labor Day from Southern Connecticut Weather!
From a meteorological perspective, yesterday ushered in meteorological fall. From a societal perspective, Labor Day marks the unofficial start of fall. Astronomical fall doesn't begin for a few weeks but it's time to turn the page as we head into a month of transition.
While we can (and likely will) still get well above normal temperature days and humid days, climatology in September accelerates the step down in temperature as we lose more daylight each day.
Before we review and grade the summer that was, let's look ahead at what normal means for fall in Connecticut.
Fall Climatology
September
Hartford
September 1 Average High Temperature: 81
September 1 Average Low Temperature: 59
Sunset Time: 7:23pm
September 15 Average High Temperature: 76
September 15 Average Low Temperature: 54
Sunset Time: 6:59pm
September 30 Average High Temperature: 70
September 30 Average Low Temperature: 48
Sunset Time: 6:33pm
Total Precipitation: 4.39"
Bridgeport
September 1 Average High Temperature: 80
September 1 Average Low Temperature: 64
Sunset Time: 7:24pm
September 15 Average High Temperature: 76
September 15 Average Low Temperature: 60
Sunset Time: 7:01pm
September 30 Average High Temperature: 70
September 30 Average Low Temperature: 54
Sunset Time: 6:35pm
Total Precipitation: 3.96"
October
Hartford
October 1 Average High Temperature: 70
October 1 Average Low Temperature: 48
Sunset Time: 6:31pm
October 15 Average High Temperature: 64
October 15 Average Low Temperature: 43
Sunset Time: 6:08pm
October 31 Average High Temperature: 58
October 31 Average Low Temperature: 38
Sunset Time: 5:45pm
Total Precipitation: 4.52"
Total Snowfall: 0.7"
Bridgeport
October 1 Average High Temperature: 70
October 1 Average Low Temperature: 54
Sunset Time: 6:33pm
October 15 Average High Temperature: 65
October 15 Average Low Temperature: 49
Sunset Time: 6:11pm
October 31 Average High Temperature: 59
October 31 Average Low Temperature: 43
Sunset Time: 5:48pm
Total Precipitation: 3.84"
Total Snowfall: 0.1"
November
Hartford
November 1 Average High Temperature: 57
November 1 Average Low Temperature: 37
Sunset Time: 5:44pm
November 15 Average High Temperature: 52
November 15 Average Low Temperature: 33
Sunset Time: 4:29pm
November 30 Average High Temperature: 46
November 30 Average Low Temperature: 29
Sunset Time: 4:21pm
Total Precipitation: 3.51"
Total Snowfall: 1.4"
Bridgeport
November 1 Average High Temperature: 59
November 1 Average Low Temperature: 43
Sunset Time: 5:47pm
November 15 Average High Temperature: 54
November 15 Average Low Temperature: 39
Sunset Time: 4:33pm
November 30 Average High Temperature: 49
November 30 Average Low Temperature: 34
Sunset Time: 4:24pm
Total Precipitation: 3.11"
Total Snowfall: 0.9"
So what do we see here? Normal temperatures decline sharply in the fall as we hurdle toward winter, and by October, we can expect our first frosts and potential freezes, especially inland. September and October is usually wet, as we start to see our first coastal (rain) nor'easters and perhaps tropical/hybrid storms. While we do average negligible amounts of snowfall in October, it's not until November where measurable snowfall is really likely.
Warmer than normal can be quite nice this time of year, and we can see temperatures reach 80 even into November, but the tradeoff with that is extended mosquito and tick seasons.
Now, let's look to the summer that was.
Grading the SCW Summer 2024 Forecast
From a meteorological perspective, yesterday ushered in meteorological fall. From a societal perspective, Labor Day marks the unofficial start of fall. Astronomical fall doesn't begin for a few weeks but it's time to turn the page as we head into a month of transition.
While we can (and likely will) still get well above normal temperature days and humid days, climatology in September accelerates the step down in temperature as we lose more daylight each day.
Before we review and grade the summer that was, let's look ahead at what normal means for fall in Connecticut.
Fall Climatology
September
Hartford
September 1 Average High Temperature: 81
September 1 Average Low Temperature: 59
Sunset Time: 7:23pm
September 15 Average High Temperature: 76
September 15 Average Low Temperature: 54
Sunset Time: 6:59pm
September 30 Average High Temperature: 70
September 30 Average Low Temperature: 48
Sunset Time: 6:33pm
Total Precipitation: 4.39"
Bridgeport
September 1 Average High Temperature: 80
September 1 Average Low Temperature: 64
Sunset Time: 7:24pm
September 15 Average High Temperature: 76
September 15 Average Low Temperature: 60
Sunset Time: 7:01pm
September 30 Average High Temperature: 70
September 30 Average Low Temperature: 54
Sunset Time: 6:35pm
Total Precipitation: 3.96"
October
Hartford
October 1 Average High Temperature: 70
October 1 Average Low Temperature: 48
Sunset Time: 6:31pm
October 15 Average High Temperature: 64
October 15 Average Low Temperature: 43
Sunset Time: 6:08pm
October 31 Average High Temperature: 58
October 31 Average Low Temperature: 38
Sunset Time: 5:45pm
Total Precipitation: 4.52"
Total Snowfall: 0.7"
Bridgeport
October 1 Average High Temperature: 70
October 1 Average Low Temperature: 54
Sunset Time: 6:33pm
October 15 Average High Temperature: 65
October 15 Average Low Temperature: 49
Sunset Time: 6:11pm
October 31 Average High Temperature: 59
October 31 Average Low Temperature: 43
Sunset Time: 5:48pm
Total Precipitation: 3.84"
Total Snowfall: 0.1"
November
Hartford
November 1 Average High Temperature: 57
November 1 Average Low Temperature: 37
Sunset Time: 5:44pm
November 15 Average High Temperature: 52
November 15 Average Low Temperature: 33
Sunset Time: 4:29pm
November 30 Average High Temperature: 46
November 30 Average Low Temperature: 29
Sunset Time: 4:21pm
Total Precipitation: 3.51"
Total Snowfall: 1.4"
Bridgeport
November 1 Average High Temperature: 59
November 1 Average Low Temperature: 43
Sunset Time: 5:47pm
November 15 Average High Temperature: 54
November 15 Average Low Temperature: 39
Sunset Time: 4:33pm
November 30 Average High Temperature: 49
November 30 Average Low Temperature: 34
Sunset Time: 4:24pm
Total Precipitation: 3.11"
Total Snowfall: 0.9"
So what do we see here? Normal temperatures decline sharply in the fall as we hurdle toward winter, and by October, we can expect our first frosts and potential freezes, especially inland. September and October is usually wet, as we start to see our first coastal (rain) nor'easters and perhaps tropical/hybrid storms. While we do average negligible amounts of snowfall in October, it's not until November where measurable snowfall is really likely.
Warmer than normal can be quite nice this time of year, and we can see temperatures reach 80 even into November, but the tradeoff with that is extended mosquito and tick seasons.
Now, let's look to the summer that was.
Grading the SCW Summer 2024 Forecast
Above: Using a longer period of record, here's the 130 year ranking of summer temperatures across the Continental United States. Once again, this was one of the warmest summers on record in Connecticut. Image courtesy of Brian Brettschneider.
Below: The temperature departure for meteorological summer, which consists of June-August.
Below: The temperature departure for meteorological summer, which consists of June-August.
Forecast Recap
The most memorable aspect of the summer is the thing we got most right. We expected this to be a sultry summer, and it was that in spades. Even though the high temperatures weren't particularly memorable, the oppressive humidity was. The summer pattern did in fact have a strong Atlantic ridge that brought in frequent bouts of moisture and humidity. That also set the stage for our precipitation pattern, and to an extent, the historic flooding we saw in SW CT.
It's not going anywhere either, folks. Summers are a lot more humid than when we were kids thanks to the increased warmth and atmospheric moisture due to climate change, and in the last 30 years the data shows an increasing trend that's not letting up. More humidity and heat is likely in the years and likely decades to come.
Let's dive into specifics.
The most memorable aspect of the summer is the thing we got most right. We expected this to be a sultry summer, and it was that in spades. Even though the high temperatures weren't particularly memorable, the oppressive humidity was. The summer pattern did in fact have a strong Atlantic ridge that brought in frequent bouts of moisture and humidity. That also set the stage for our precipitation pattern, and to an extent, the historic flooding we saw in SW CT.
It's not going anywhere either, folks. Summers are a lot more humid than when we were kids thanks to the increased warmth and atmospheric moisture due to climate change, and in the last 30 years the data shows an increasing trend that's not letting up. More humidity and heat is likely in the years and likely decades to come.
Let's dive into specifics.
Above: the precipitation departure as a percent of normal through the summer. Once again. Wetter than normal.
Precipitation
"While I think we won't be as wet as last summer, I do think we will be solidly wetter than normal, on the order of 110-130% above normal. Even this statement has me nervous for a few reasons."
"This is a big variable, and if I were to hazard a guess, I would say we get some significant rainfall from at least one tropical system this summer, likely in the latter part of the summer as the tropics become more active. That alone could make this forecast too low."
Well, we ended up above normal and right in the range that was expected, even accounting for the unprecedented rainfall event in SW CT that pushed anomalies to near 150% of normal for the area. We did get significant rainfall from the influence of Tropical Storm Debby, though not as much as was forecast at the time. It was that rainfall that guaranteed us to be above normal heading into the latter part of August.
Grade: A
Temperature
"With total 90 degree days being around 20 for BDL and 10 for BDR, I expect us to be slightly above normal in that category. The bulk of this heat will be in July and August as La Nina establishes itself right as we reach our climatological peak. It may not be hot now, but eventually it will be."
"The summer will be more memorable in the humidity category than the absolute temperature category, though keep in mind Hartford averages days in the mid to upper 90s while the coast gets hot days as well, though not as frequently."
In terms of 90 degree days, we were accurate in Hartford which had 9 such days in June, 11 in July, and 6 in August (mostly early August), but for Bridgeport, were were off. It was far more humid than hot in terms of air temperature. Bridgeport had 7 90 degree days this summer, which is lower than the normal of 9. We get dinged there as a result, and I think if we didn't have such a transition away from hotter days after early August we could have gotten Bridgeport to normal. That said, nobody would question that it was a hot summer.
Grade: B+
Severe Storms
There is moderate confidence that this is a more active severe thunderstorm season than normal, though only slightly above, due to the likelihood of central US and western Atlantic ridging alongside possible troughing to our west pumping moisture and potentially giving a few active storm periods.
Early on, it looked like we were heading toward a historic storm season, with multiple consecutive days of high end severe storm activity for the state. However, things quieted down in July, which brought us back to what I'd consider above normal but not overwhelmingly so. We had some storm days late in July and August, but nothing like the initial activity we saw in June.
Grade: A-
Overall
This ended up being an excellent summer forecast. You can't account for an historic mesoscale rain event like what we saw, but between the temperature forecast being on track, the precipitation forecast landing in the zone expected for much of the state, and a very good forecast on severe season, with periodic bouts of severe potential, this was about as good as one can do. In the future it'd be good to go month by month and try our hand at more detailed forecasting.
Overall Grade: A-
As always, please like, share, and interact with us on our social media--on Facebook to share our discussions, and follow us on Twitter @southernctwx to retweet our posts. Hit the buttons below to join.
Thank you for reading SCW.
-DB
Precipitation
"While I think we won't be as wet as last summer, I do think we will be solidly wetter than normal, on the order of 110-130% above normal. Even this statement has me nervous for a few reasons."
"This is a big variable, and if I were to hazard a guess, I would say we get some significant rainfall from at least one tropical system this summer, likely in the latter part of the summer as the tropics become more active. That alone could make this forecast too low."
Well, we ended up above normal and right in the range that was expected, even accounting for the unprecedented rainfall event in SW CT that pushed anomalies to near 150% of normal for the area. We did get significant rainfall from the influence of Tropical Storm Debby, though not as much as was forecast at the time. It was that rainfall that guaranteed us to be above normal heading into the latter part of August.
Grade: A
Temperature
"With total 90 degree days being around 20 for BDL and 10 for BDR, I expect us to be slightly above normal in that category. The bulk of this heat will be in July and August as La Nina establishes itself right as we reach our climatological peak. It may not be hot now, but eventually it will be."
"The summer will be more memorable in the humidity category than the absolute temperature category, though keep in mind Hartford averages days in the mid to upper 90s while the coast gets hot days as well, though not as frequently."
In terms of 90 degree days, we were accurate in Hartford which had 9 such days in June, 11 in July, and 6 in August (mostly early August), but for Bridgeport, were were off. It was far more humid than hot in terms of air temperature. Bridgeport had 7 90 degree days this summer, which is lower than the normal of 9. We get dinged there as a result, and I think if we didn't have such a transition away from hotter days after early August we could have gotten Bridgeport to normal. That said, nobody would question that it was a hot summer.
Grade: B+
Severe Storms
There is moderate confidence that this is a more active severe thunderstorm season than normal, though only slightly above, due to the likelihood of central US and western Atlantic ridging alongside possible troughing to our west pumping moisture and potentially giving a few active storm periods.
Early on, it looked like we were heading toward a historic storm season, with multiple consecutive days of high end severe storm activity for the state. However, things quieted down in July, which brought us back to what I'd consider above normal but not overwhelmingly so. We had some storm days late in July and August, but nothing like the initial activity we saw in June.
Grade: A-
Overall
This ended up being an excellent summer forecast. You can't account for an historic mesoscale rain event like what we saw, but between the temperature forecast being on track, the precipitation forecast landing in the zone expected for much of the state, and a very good forecast on severe season, with periodic bouts of severe potential, this was about as good as one can do. In the future it'd be good to go month by month and try our hand at more detailed forecasting.
Overall Grade: A-
As always, please like, share, and interact with us on our social media--on Facebook to share our discussions, and follow us on Twitter @southernctwx to retweet our posts. Hit the buttons below to join.
Thank you for reading SCW.
-DB
