I found the source file:

https://www.cdc.gov/flu/weekly/weeklyarchives2019-2020/data/...

I can't find where this is linked to on the CDC site, but that is the source data for the tweet.

From the csv, here is "All Deaths" for first 12 weeks of each year:

  Year,2020,2019,2018,2017,2016,2015,2014
  Week
  1,58961,58289,66134,59763,55788,61737,53277
  2,58962,58351,67495,60980,55525,61141,55620
  3,57371,58193,64647,59293,55182,58628,54580
  4,56666,57834,62780,58047,55606,57269,54085
  5,55849,58122,60974,58432,54896,57284,53955
  6,55992,58489,61110,59038,55106,56420,53397
  7,54246,57915,59779,58479,55785,56348,53815
  8,53745,57856,57793,58288,54873,55668,52642
  9,53382,57915,56692,57256,55875,55732,51674
  10,51978,58488,57093,57477,56112,55272,52058
  11,47655,57869,56326,56656,54462,54262,51782
  12,40002,57086,55766,57045,54662,53238,51385

  Year,2020,2019,2018,2017,2016,2015,2014
  Week
  1,58961,58289,66134,59763,55788,61737,53277
  2,117923,116640,133629,120743,111313,122878,108897
  3,175294,174833,198276,180036,166495,181506,163477
  4,231960,232667,261056,238083,222101,238775,217562
  5,287809,290789,322030,296515,276997,296059,271517
  6,343801,349278,383140,355553,332103,352479,324914
  7,398047,407193,442919,414032,387888,408827,378729
  8,451792,465049,500712,472320,442761,464495,431371
  9,505174,522964,557404,529576,498636,520227,483045
  10,557152,581452,614497,587053,554748,575499,535103
  11,604807,639321,670823,643709,609210,629761,586885
  12,644809,696407,726589,700754,663872,682999,638270

Plugging it into a graph is more dramatic, especially looking at the numbers in 2018 (2017-2018 season).

I wish I could find a page on the CDC website that links to these reports, but you can easily get the latest report by just increasing the week number by 1.