The calendar still says summer, but the start of school -- and football season -- means we're in a time of transition. While we spent the summer stocking up on refreshing juice pops, T-shirts and pool toys, what we'll buy this fall is different.

Costco also is in that in-between stage, still selling some of summer's staples while introducing merchandise for cooler weather and holidays ahead. From lingering school supplies to stuff for the final barbecues of the year to holiday treats, Costco is ready for the change of seasons.

As you start to stock your shelves for colder weather ahead, here are some great deals on the Costco shelves.

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Hamburger Patties

"With summer winding down, it's a good time to get all the grilling in that you can," said Julie Ramhold, consumer analyst for DealNews.com. "And if you're planning to grill for the beginning of tailgate season, buying in bulk from Costco means having to buy less overall. Unless you have a  tried-and-true secret burger recipe and no other will do, the patties at Costco are solid picks that provide a tasty shortcut."

You can get 18 frozen patties for between $26 and $30 -- depending on the type -- which is about $1.44 to $1.67 per patty.

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Gel Pens

Back-to-school season is here, and Ramhold recommends "[grabbing] extra school supplies before they disappear from shelves... Costco has a few different types of gel pens that are perfect for students and office workers alike."

You can find a UNI-BALL 12-pack for $12.39, a 20-pack of Pilot G2 pens for around $19.99 and a 34-pack of BIC soft feel retractable ballpoint pens for $10.99.

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Leaf Blower

If you're not looking forward to raking and bagging the mass of leaves in your yard this fall, it's time for a leaf blower. One of the things Costco is known for is offering items with some extras in a bundle, and that's what it has done with the Greenworks 80V Jet Blower.

While the price sounds high at $239.99, it's packaged with two rechargeable batteries and a charger. At Amazon, the blower is a la carte -- you buy the tool and the batteries separately, and the cost will well exceed the Costco price.

Starbucks Hot Cocoa Mix

As the nights grow chillier, cuddling up on the couch with a cup of delicious hot cocoa just might sound good. Or, fill a thermos and head to the football game at your local high school. The rich Starbucks mix will make a much better cup than what you can buy at the stadium concession stand.

If you and your family consume a lot of hot cocoa, buy it in bulk at Costco, where two 30-ounce cans cost $34.99.

Allergy Medications

"If the end of summer and beginning of fall brings allergy symptoms your way, then it's time to stock up on daily allergy meds," Ramhold said. "Opt for Costco's Kirkland Signature brand to save even more -- whether you prefer Zyrtec, Allegra, Flonase or Claritin -- as Costco has store-brand versions of all of these items.

"A bottle of 365 Aller-Tec pills, for instance, is anywhere from $13 to $16, depending on if it's on sale," Ramhold added. "And that's a year's supply if you're the only one taking it. Other meds will vary in price, but all of them are cheaper to buy Kirkland Signature's brand over name brand, and they're definitely cheaper to buy in bulk than shopping elsewhere."

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Laundry Soap Packets

You can do a load of laundry a day for almost a year with the 350-pack of Nellie's Laundry Nuggets -- premeasured soap packets that you just throw in with the dirty clothes. The giant case costs $84.00, which sounds steep. But consider how much you spend picking up the laundry packs when you do your weekly grocery shopping.

If you shop at Ralphs in Southern California, for example, you'll pay $8.49 for a 19-count package of All with Stainlifters Free Clear Laundry Detergent Mighty Pacs -- about 44 cents a load. With the Nellie's nuggets, the per-load price is about 24 cents -- and you won't run out for a long, long time.

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Laura Beck contributed to the reporting for this article.

This article originally appeared on GOBankingRates.com: 6 Costco Items To Stock Up on for the End of Summer