Southwest Michigan had it’s first widespread freeze of the fall today.

Here is a quick look at what the low temperatures were this morning over all of Lower Michigan, and a summary of what is normal for a few selected stations in Southwest Michigan. This year, at most stations the first freeze was later than what would be the mean first freeze date.

The weather over the next two weeks will feature some warm and dry weather as well as cold and wet weather. Mostly it will be warm dry over the western CONUS into next week. Over the eastern CONUS it will mostly be cooler and wet. A significant warm up may follow over the eastern CONUS by the middle of next week.

Typical of fall we will see a warm up, then it will rain and get cooler, only to warm up by early next week. Then it will get wet and cooler once again.

Expect the wet and cool weather over Northern Midwest into New England, including the Great Lakes, to persist into early next week. An impressively large blocking upper-level high, over central Canada will keep the storm track over the northern CONUS into early next week. It will also allow a subtropical system to track along the Gulf Coast over the next few days.

After having 4 days with highs in the 80s over Southwest Michigan, to start October, a series of cold fronts will lower our high temperatures by Saturday into the lower 50s. The cooler temperatures are expected to last into the middle of next week before another slow warm up begins. Widespread rainfall, mostly between a quarter and half an inch will occur Thursday as the front moves through. Lake effect rain showers are expected into early next week.

It will fell like fall by Friday morning and that chilly and showery weather my last into Tuesday morning before the system is far enough to east to allow for some clearing. It will remain chilly Tuesday into Wednesday before a warm up starts by Thursday of next week.

Some rather dramatic changes are likely in our weather over the western Great Lakes this week into early next week. Highs in the 80s are expected Sunday into Tuesday, then highs are expected to fall into lower to mid 50s by next weekend. Expect widespread rainfall during the midweek period too.

At the risk of going overboard on the Summer of 2023, I have another set of charts you may want to look at.

I through it would be fun and informative to see the frequency for hot days across our Nation.

Here I have the frequency for highs in the 90s across the CONUS (Continental United States), the longest streak across the CONUS, the frequency of lows of 70 or more and I few more NCEI charts to show how hot of a summer this was both nationally and regionally. I also have a few precipitation maps so you can see that the great frequency for hot weather was were it rained less, relative to normal for that area.

I have added 2 slides to this presentation ( 8 and 9). These two slides show that what one uses for the “normal”, greatly impacts what the departure from normal looks like. I used 1991 to 2020, the official NWS normal period for the image on the top left, then 1895 to 2000 for the image on the top right, not the area of below normal is significantly less. That is because the period 1991 to 2020 was warmer than the 1895 to 2000 period. On the bottom left the mean is 1895 to 2020, that has no below normal areas. This seems questionable to me since the ranked normal’s on the next slide look a lot like the 1895 to 2000 on slide 8. I added this because I was getting some questions on this matter. I hope this helps.

Here is my forecast for this coming week, plus a look at the current fall foliage report. The short story is warm and dry this week of the Great Lakes and northern New England. Wet along most of the East Coast and over the western CONUS. It will be cool and wet over the western CONUS.

I am expecting warm and dry weather this week over Michigan but warm and wet over the east coat, and cool and wet over the west coast.

Fall Foliage Map

Here is my updated version of the summer of 2023 climate. I have added some details on Southwest Michigan including the severe weather events this summer. I have also added slides on the large scale pattern, that is our transition from La Nina this past winter to El Nino this summer. This lead to persistent blocking over North America, which is why there were persistent heat over the south and wet weather over the eastern 1/3 of the CONUS.

This was a summer that featured persistent weather patterns over most of North America and lead to one of the most active Canadian wildfire seasons on record. It also lead the the 15th warmest summer on record (back to 1895) over the CONUS.

GRR August 24th Event Link

DTX August 24th Event Link

DTX August 24th Event Flooding Link

DTX EVENT SUMMARYhttps://www.weather.gov/dtx/severeweather07202023
DTX EVENT SUMMARY

How did the Summer of 2023 turn out weather wise across the CONUS (continental United States)? How did the summer forecast I posted in March turn out (very good for the temperature, not so great for the precipitation)

While it was the 15th warmest summer on record nationally, not all of the CONUS had a warm summer. You may want to find out how your area did relative to normal for this summer.