Weather radio just gives off high pitch squeal and no weather info.

SOURCE: my midalnd weather radio WR-100

The high pitch sound is a sign of the autooscillation of the intermediate frequency amplifier from the tuner in your radio - hardware defect. The only way to fix that is to replace the tuner and realign it. This would cost you about $100 for the part and labor.
Since you can buy a brand new unit for less than $40 it's clear what you should do.

SOURCE: need to make sure programmed

Program the Midland 74-109 Weather Radio
a) Turn unit on. Extend the antenna. Adjust volume up slowly; Do you hear anything? If not, try replacing the 9 volt battery with a fresh one, in the accessible battery compartment underneath the unit. Repeat above steps.
b) If no sound is heard, turn unit over and look for "WEATHER" slide switch on bottom. With unit on & volume adjusted to comfortable hearing level, slowly slide switch down (or up) through various frequencies [1)162.550, 2) 162.400, 3) 162.475, 4) 162.425, 5) 162.450, 6) 162.500, 7) 162.525] until voice transmissions are heard. This should be the closest National Weather Service (NWS) broadcast for your area. Check the NWS website at http://www.nws.noaa.gov/nwr/nwrbro.htm for your state, click on the state name, and look for the site name or site location nearest you. The frequency for that site should be the strongest, and appropriate for your area.
c) You can set the alert tone, for special weather alert broadcasts, on the bottom of the unit on the slide switch marked "ALERT". Set the switch to the desired type of alert: 1) LED [LED on top of unit (marked ALERT) lights up when alert is broadcast-no siren tone/alarm is heard] 2) LED & ALARM [LED lights up and alarm/ siren tone is heard] 3) VOICE [LED on top of unit lights up and voice broadcast is heard, only; no siren tone/alarm is heard].
d) Be sure to press the "ALERT" button on top of the unit and leave the volume at a comfortable listening level to hear weather alerts for your area (Alert LED on top of unit lights up to show Alert function is active). You can test the present volume level by pressing the "TEST" button. Be sure to press the "ALERT" button again after listening to the volume level to re-set the Alert function. You can listen to weather broadcasts anytime, by pressing the "WEATHER" button. After listening, be sure to re-press the "ALERT" button to reset the Alert function.
e) 9 volt battery life should last about 6 to 7 months, depending on how much unit is used an number of alerts received. Replace battery every 6 months, or when you replace your smoke alarm battery, or at beginning and end of daylight savings time. A 12 volt AC adapter to replace the battery, can be used. One should have been supplied with unit. If not, a replacement can be found at Radio Shack.
f) This should complete your Midland Weather Alert Radio Model 74-109 programming.

SOURCE: I have midland wr-100 weather

Good morning, afternoon, evening or night; whatever time you're reading this. Thank you for choosing FixYa to assist you with your problem. The problem is that you are hearing a high pitch tone coming from the speaker. First check to make sure the weather mode is on. To do this, switch the radio to the right side and make sure the Weather Radio On/Off switch is switched to On. You should also check the alarm to make sure it's not on and set. If the alarm is on, turn it off. Your alert type may also be a cause for this. If your alert type is set on TONE, try changing it to DISPLAY or VOICE. Reply back if you still receive problems. Thank you for choosing FixYa as your one-stop solution spot for your problems. Have a nice day, evening or night; whatever time you are viewing this. Hope this helps and remember our site the next time you need troubleshooting assistance.