Olivia Culpo is ‘not ready for summer to end’ as she poses in a black string bikini and a sun hat

Summer comes to a close in the Northern Hemisphere on September 22.

And Olivia Culpo bid the season farewell by uploading a stunning bikini-clad portrait to Instagram on Monday.

‘Not ready for summer to end…’ captioned the 28-year-old former Miss Universe as she lounged in a cozy outdoor canopy.

Culpo appeared to be wearing a black string bikini that highlighted her refined curves and enviable tan.

Her brunette tresses were tied back into a bun, while a stylish woven sunhat rested atop her head.

She posed with both of her hands positioned on the brim of her hat as she sat on her legs and turned her head to the side.

The luxe canopy was made out of branches and lined with plenty of comfy pillows. 

Olivia’s post on Monday comes just two days after the former girlfriend of Nick Jonas was spotted having a girls day with her younger sister Sophia in Los Angeles.

The siblings had a blast sifting through various styles of purses at a storefront for Italian luxury designer Bottega Veneta.

Olivia and Sophia each left the high end store with brand new additions to their handbag collection, before heading to a nearby restaurant for dinner.

Although their outing took place on Saturday, Olivia took to Instagram on Sunday to share a few portraits that her sister snapped of her during dinner.

‘Really missed the wining and dining,’ she wrote, while posing next to a glass of white wine. 

Wearing her dark hair down in an attractive bob, Olivia slipped into a white sleeveless shirt and tucked the top into a pair of high-waisted jeans. 

She cinched a belt around her trousers to emphasize her enviably trim waistline as she watched the sunset with her sister.  

Although Olivia is often seen with a smile on her face, the brunette beauty revealed last month that she suffers from endometriosis, a painful condition in which the uterine lining grows outside of the uterus. 

In a recent interview with People, Culpo explained that she is hoping to manage the condition via a ‘holistic route as of now,’ rather than undergoing an immediate laparoscopy. 

‘I want to try to see if I can figure some things out for myself, but we’ll see. It’s a journey. Every month is different because I try different things every month. But I’ll definitely keep everybody posted on what works for me, and eventually having to get the surgery because it really depends. Everyone’s different,’ she said.

Olivia had never spoken about her diagnosis publicly until this past August, which she admitted ‘was something that [she] was nervous to share.’  

‘Because I really didn’t know if people would be familiar with the condition, and it turns out a lot of women are. I was shocked to see how many women have also suffered from endometriosis, and how many questions women have about painful periods.’

She emphasized the seriousness of the condition and that painful periods are ‘not normal’ and ‘could get in the way of your fertility.’