PHOTO BY MAT TAYLOR The first rain of 2009 on Monday combined with below-freezing temperatures andt resulted in ice covering trees, fences and most other exposed surfaces. With the first dose of winter weather recently passing through parts of the state, the National Weather Service's Fort Worth office has released a guide to surviving the winter season.

When threatening weather is imminent, NWS will issue watches, warnings, advisories and statements to keep the public informed and prepared, officials note.

Following is a guide for weather events the NWS may issue in case of bad weather.

Winter storm outlook: Issued when there is a good chance of a major winter weather event beyond 36 hours.

Winter storm watch: Issued when the following conditions are possible within 12 to 36 hours: heavy snowfall of four or more inches in 12 hours, or six or more inches in 24 hours; freezing rain and/or freezing drizzle accumulating to a depth of 0.25 inches or greater; or heavy sleet accumulating to a depth of 1/2 inch or more.

Winter storm warning: Issued when the hazardous weather conditions defined above are occurring or expected to occur within 12 hours.

Freeze warning: Issued for the first occurrence of freezing temperatures in the fall, for late freezes during the spring, or for a freeze expected to occur after a prolonged warm spell.

Snow advisory: Issued when snow is expected, but the accumulations will be less than four inches in six hours, or less than six inches in 24 hours.

Freezing rain advisory: Issued when freezing rain is expected, but accumulation will be less than 0.25 inch.

Freezing drizzle advisory: Issued when freezing drizzle is expected with little or no accumulation.

Wind chill advisory: Issued when forecast wind chill values will be below minus-20 degrees.