The death toll from the Missouri tornado  on Sunday now stands at 122, making it the single deadliest tornado in the US since at least 1950.
The greatest destruction was in the small city of Joplin, Missouri , where at least a quarter of the city's homes and businesses were damaged and much of the city was left isolated and in the dark, with telephone connections largely cut off and many homes without electricity. Joplin authorities still can't estimate how many residents are missing.
As organizations and first responders take advantage of the first sunny days since the tornado hit to comb through debris and crumbled buildings and to provide emergency relief, food and shelter, there are many ways people across the country can help.
The Missouri State Emergency Management Agency is providing details on donating and volunteering .
Feeding America is seeking donations to distribute non-perishable food, emergency cleaning supplies, and personal hygiene items. You can call (800) 771-2303 or donate online .
AmeriCares is working with the National Conference of Community Health Centers to assess needs and mobilize a response for affected communities. This expands AmeriCares' tornado relief operation in numerous Southern states recovering from their own recent disasters. Donations to AmeriCares can be made online  or by phone at 1-800-486-HELP. Those interested in volunteering should list their availability and expertise on their Joplin Storm Recovery Volunteer Form .
Heart to Heart International has sent volunteer medical professionals and their mobile medical clinic to the devastated communities in Kansas and Missouri. The group  is also sending hygiene kits for people displaced by the storms. You can donate or sign up to be a volunteer online  or by phone at 1-913-764-5200.
The American Red Cross has opened shelters in Missouri and Minnesota. The shelter in Joplin is located at Missouri Southern State University and is offering food, cleanup supplies and comfort kits along with immediate care by healthcare workers. Text "REDCROSS" to 90999 to make a $10 donation, or visit the website  to donate, give blood or volunteer.
Finally, OzarksFirst.com , a local community and news site, has put together a comprehensive resource with help hotlines, phone numbers and web pages for volunteers and victims. It provides emergency numbers, the state senator’s office number and special hotlines for nurses and doctors looking to lend a hand. Help pages include the Show-Me Response  for medical professionals, a Facebook Page for the local hospital, which was badly damaged in the twister, and even resources for locating and reuniting with lost pets.
Please use the comments field below to let us know about other groups and initiatives I've missed.