Hurricane Harvey has ravaged southeastern Texas. Rain has flooded Houston . People are waiting in hours-long lines to buy groceries . The storm is not yet over, but companies are already starting to donate money to relief efforts.

Wal-Mart — Wal-Mart (WMT) and the company's foundation will provide cash and product donations of at least $1 million to organizations helping with relief, such as the American Red Cross, Salvation Army and Convoy of Hope.

PepsiCo — PepsiCo (PEP) and its foundation are providing more than $1,000,000 in cash and products to the Red Cross.

Starbucks — The Starbucks (SBUX) Foundation will donate $250,000 to Hurricane Harvey relief. The coffee chain will also allow customers to make a donation to the American Red Cross in its stores. Employees who donate money can request a matching donation.

Microsoft — Microsoft (MSFT) has donated $100,000 to the American Red Cross "as an initial step" to help those affected, the company said in a blog post. "More help is needed, and the company and its employees pledged to do more," the company wrote. A link to donate was also included in the post.

Aetna — The Aetna (AET) Foundation will give $100,000 to the American Red Cross, $100,000 to the Community Foundation of Greater Houston and $50,000 to Team Rubicon.

Allergan — The Allergan (AGN) Foundation will donate $100,000 to the American Red Cross.

Amazon and Whole Foods Market — Amazon (AMZN) and Whole Foods Market will match up to $1 million in donations made to the American Red Cross via Amazon. The website includes a link to make a donation as well as one to send essential items from the Red Cross' wish list.

Caterpillar — The Caterpillar (CAT) Foundation is giving $300,000 to the American Red Cross. The company has started sending power generation equipment from other parts of the country and begun staging equipment in anticipation of clean-up efforts, CEO Jim Umpleby said in a statement.

Cheniere Energy — Cheniere (NYSE American: LNG)will donate $1 million to the American Red Cross.

Lowe's — Lowe's (LOW) has contributed $500,000 to the American Red Cross Disaster Relief. The hardware chain has also started allowing customers to donate in-stores and online.

Home Depot — The Home Depot (HD) Foundation has pledged $1 million to organizations including the American Red Cross, Salvation Army, Convoy of Hope, Operation Blessing and Team Rubicon. The hardware store company will also send its Team Depot volunteers to help the cleanup effort and deliver supplies to the affected areas.

Western Union — The Western Union (WU) Foundation is donating $30,000 to the American Red Cross. It will also match contributions from employees. Customers can also donate directly to the Red Cross.

Apple — Apple (AAPL) has donated $2 million to the American Red Cross. It has also started allowing people to make donations through iTunes.

Google — Google (GOOGL) is making a $250,000 grant to the American Red Cross and will match employee donations up to $250,000. The contributions will go toward the American Red Cross, Save the Children, Habitat for Humanity and Team Rubicon.

JPMorgan Chase — JPMorgan Chase (JPM) will donate $1 million to the American Red Cross and other organizations who are working to help those affected.

Target — Target (TGT) will donate $500,000, which will be distributed to the American Red Cross, The Salvation Army and Team Rubicon.

UPS — The UPS (UPS) Foundation has pledged more than $1 million to organizations including the American Red Cross and The Salvation Army..

ABInBev — ABInBev (Euronext Brussels: ABI-BE)'s emergency water program has sent more than 155,000 cans of drinking water to Baton Rouge, Louisiana, and Arlington, Texas, to help those in need.

These donations were all announced before the end of business on Monday.

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