The grades of five oil and gas stocks are on the rise this week on Portfolio Grader. Each of these stocks is rated an “A” (“strong buy”) or “B” overall (“buy”).

Chesapeake Midstream Partners (CHKM) is making progress this week as its rating of C (“hold”) from last week increases to a B (“buy”) rating this week. Chesapeake Midstream Partners owns, operates, develops, and acquires natural gas, natural gas liquids, and oil gathering systems, as well as other midstream energy assets in the United States. For more information, get Portfolio Grader’s complete analysis of CHKM stock.

This week, Oiltanking Partners, L.P. (OILT) is making solid headway. The company’s rating improves to an A (“strong buy”) from last week’s B (“buy”) rating. Oiltanking Partners engages in the terminaling, storage and transportation of crude oil, refined petroleum products and liquefied petroleum gas. For more information, get Portfolio Grader’s complete analysis of OILT stock.

This week, U.S. Energy Corp.’s (USEG) ratings are up from a C last week to a B. U. S. Energy explores for oil and natural gas. For more information, get Portfolio Grader’s complete analysis of USEG stock.

This week, Cabot Oil & Gas Corporation (COG) pushes up from a B to an A rating. Cabot Oil & Gas is an independent company that develops, explores, produces and markets natural gas, and transports, stores, and gathers it for resale. The stock price has risen 7.8% over the past month, better than the 1.7% decrease the S&P 500 has seen over the same period of time. For more information, get Portfolio Grader’s complete analysis of COG stock.

Ur-Energy (URG) improves from a C to a B rating this week. Ur-Energy is a development-stage junior mining company engaged in the identification, acquisition, evaluation, exploration and development of uranium mineral properties in Canada and the United States. For more information, get Portfolio Grader’s complete analysis of URG stock.

Louis Navellier’s proprietary Portfolio Grader stock ranking system assesses roughly 5,000 companies every week based on a number of fundamental and quantitative measures. Stocks are given a letter grade based on their results — with A being “strong buy,” and F being “strong sell.” Explore the tool here.