DxCodebookFY2027 · Oct 1, 2026 – Sep 30, 2027

Category · FY2027

X37 Cataclysmic storm

  • Header · not billable
  • Codes take a 7th character

X37 is not billable. The category heads 27 billable codes in FY2027, grouped under 7 subdivisions. Its codes take a 7th character, so none is complete with fewer than 7 characters.

Where it sits

  1. Chapter 20 External causes of morbidity (V00-Y99)
  2. X30-X39 Exposure to forces of nature (X30-X39)
  3. X37 Cataclysmic storm
Billable codes
27
Subdivisions
7
CC / MCC codes
0 / 0
HCC V28 codes
0
New FY2027
0
Index entries
0

Codes in X37

  1. X37.0
    Hurricane +7th: A D S
    Needs 7th characterExempt: 2 of 3 7th characters
    Inclusion terms 2

    Inclusion terms

    • Storm surge
    • Typhoon
  2. X37.1
    Tornado +7th: A D S
    Needs 7th characterExempt: 2 of 3 7th characters
    Inclusion terms 2

    Inclusion terms

    • Cyclone
    • Twister
  3. X37.2
    Blizzard (snow)(ice) +7th: A D S
    Needs 7th characterExempt: 2 of 3 7th characters
  4. X37.3
    Dust storm +7th: A D S
    Needs 7th characterExempt: 2 of 3 7th characters
  5. X37.4
    Tidalwave
    Header
  6. X37.41
    Tidal wave due to earthquake or volcanic eruption +7th: A D S
    Needs 7th characterExempt: 2 of 3 7th characters
    Inclusion terms 2

    Inclusion terms

    • Tidal wave NOS
    • Tsunami
  7. X37.42
    Tidal wave due to storm +7th: A D S
    Needs 7th characterExempt: 2 of 3 7th characters
  8. X37.43
    Tidal wave due to landslide +7th: A D S
    Needs 7th characterExempt: 2 of 3 7th characters
  9. X37.8
    Other cataclysmic storms +7th: A D S
    Needs 7th characterExempt: 2 of 3 7th characters
    Inclusion terms 2, Excludes2 1

    Inclusion terms

    • Cloudburst
    • Torrential rain

    Excludes2

    • flood (X38) X38
  10. X37.9
    Unspecified cataclysmic storm +7th: A D S
    Needs 7th characterExempt: 2 of 3 7th characters
    Inclusion terms 1, Excludes1 1

    Inclusion terms

    • Storm NOS

    Excludes1

    • collapse of dam or man-made structure causing earth movement (X36.0) X36.0

Sources of each column. Rows marked +7th need a 7th character: pick one to build the full code; its code card has its own flags.

Instructions

Notes that also apply

Chapter 20 instructions (Notes 1): printed on the chapter 20 page.

7th characters

7th characters for X37 defined here

The appropriate 7th character is to be added to each code from category X37

7th characters for X37
7thMeaning (NCHS)
Ainitial encounter
Dsubsequent encounter
Ssequela

A code that takes a 7th character is invalid without it; the placeholder X fills a code shorter than 6 characters (Official Guidelines I.A.5). How 7th characters work.

Hierarchy