Weekly Update – August 3rd – Rain, Finally, But Still Few Mosquitoes
August 3, 2026
Mosquito numbers decline again to the lowest point since June 1st.
The average number of mosquitoes collected in traps last week was the lowest since June 1st of this year.
We are far enough through 2026 at this point to say this is just going to be a year with few mosquitoes. Prior to last week's collections we had several inches of rain fall in parts of the District, so it's possible we see a slight uptick in this week's collections (happening Monday night into Tuesday). It takes one week for mosquitoes to complete their life cycle and emerge from the water after rain, so this past weekend would be when the numbers would increase. Even a slight increase is likely going to keep us below average, however.
According to MMCD Entomologist, Dr. Scott Larson, "There are only 6-8 weeks of adult Monday night sampling left depending on the weather. The average number of mosquitoes per trap was only 19.9 whereas the 10-year average is 90.2 (or 22% of "normal")."
Here are the maps for mosquitoes collected on Monday-Tuesday, August 3-4th:
Carver County sees first mosquito pool test positive for West Nile virus
The risk of West Nile virus remains below average throughout the District this week with Culex tarsalis mosquito numbers staying low, and other Culex mosquitoes holding steady. Culex mosquitoes are not as rain dependent as the more common summer floodwater species, and as you can see in the maps above, several gravid traps collected quite a few Culex mosquitoes last week.
According to MMCD Vector Ecologist, Dr. Jordan Mandli, "While risk appears low across the District as a whole, several areas continue to experience persistent WNV activity. Most notably, traps in eastern Hennepin County are still detecting elevated activity."
The Vector Index saw another dip this week, which is good news as we head into the time of year when we typically see a surge in vector activity based on the 5- and 10-year averages:
Screenshot from a Beta version of the new Vector Index.
Upcoming Events
It's a busy time of year for public events! Come out and see staff from the Metropolitan Mosquito Control District at one of these upcoming events:
- Monday, August 10th - Sunday, August 16th - Dakota County Fair in Farmington
- Tuesday, August 11th - Safety Camp in West St. Paul
- Wednesday, August 12th - Blaine, Spring Lark Park, Mounds View Safety Camp in Blaine
- Wednesday, August 12th - Sunday, August 16th - Carver County Fair in Waconia
- Friday, August 14th - Sunday, August 16th - Game Fair in Ramsey
- Saturday, August 15th - Heritage Days Parade in St. Paul Park
- Saturday, August 15th - Vadnais Heights Days Parade in Vadnais Heights
- Saturday, August 15th - Rice & Larpenteur Block Party in St. Paul
Would you like MMCD to come to your event or speak to your group? E-mail Alex Carlson!
Win an MMCD T-Shirt!
Here is your chance to win either the new MMCD Attack Larvae T-Shirt or last year's Laser Loon shirt. Sign up for "The Weekly Buzz" newsletter with Weekly Mosquito updates. Each week there will be a trivia question at the end. Two correct answers each week will get a shirt!
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